Picture(s) of Kenwood - TS-850

Transcription

1 Seite 1 von 35 Modifications for the Kenwood TS-850 Picture(s) of Kenwood - TS TS-850S observations Engish anguage TS-850S A band transmit Engish anguage TS-850S Broadcast Band Sensitivity Engish anguage TS-850S Additiona Front Pane Functions Engish anguage Step by step instructions to disabe the broadcast band attenuation for TS-850S Engish anguage TS-850? ACC-2 audio probem Engish anguage Adjustabe moni. on CW, TS-850S Engish anguage TS-850 service manua, error corection Engish anguage TS-850S and speaker/headph Engish anguage TS-850 and Ten-Tec Titan 425 PA Engish anguage KAM-PLUS Probems!! with TS-450 & 850 Engish anguage TS-450,TS-850 feedback,acc-2 Conn Engish anguage Modification for Externa keying, whie using the interna keyer Engish anguage TS-850 Separate Receive Antenna Modification Engish anguage TS-850 Separate RX antenna input mod Engish anguage The switch box Engish anguage Computer Interface for the TS-850, without using the IF-232 Leve Converter Engish anguage TS-850 Power Output Contro Engish anguage TS-850 Leve Attenuator for DRU-2 payback audio Engish anguage TS850 + Transverter oder Preseektor German anguage TS-850S Distorted TX w/tnc connected Engish anguage TS-850S Low/no Receive sensitivity Engish anguage

2 Seite 2 von TS-850S No audio from VS-2 Engish anguage TS-850S Mixer FET change Engish anguage TS-850S "Cick noise" with NOTCH ON Engish anguage Fu transmit for the UK version of TS-850S Engish anguage TS-850 2nd RX output mod Engish anguage A Band Decoder for the Kenwood TS-850 HF-Transceiver Engish anguage TS850s ac probem Engish anguage Noise Banker Mod Kenwood TS-850 Engish anguage TS-850s noise banker mod Engish anguage TS-850 fan speed modification Engish anguage TS-850S observations Observations of KC2CT Having ived with Kenwood's TS-850S tranceiver for 5 days, here are some of my observations: Whie the manua shows 35 power-on front pane adjustments, there reay are 36. Function number 35 is set from the factory to the OFF state. We, what exacty is this unknown function? We Bunkies, this enabes the tranceiver to transmit on through mhz! Do yoursef a favor, and set this option to ON for TX inhibit! DO NOT JEAPORDIZE YOUR LICENSE! Why in the word did the factory aow this??? Maybe they don't want the Chicken Banders butchering up the rigs... Tone contro. The setup ony aows Burst or Continuous modes, there is no way to turn it OFF, even though the manua indicates there is a way. Quick memory function. You MUST pass through either the VFO A or VFO B registers to program these.. You cannot go from standard memory to quick memory directy. My 850S came out of the box running ow power (50-75w PEP), so I caed the oca ham radio deaer inquiring about service manua avaiabiity. We they had them in stock, but at a price of $50.00! Unbeievabe! Kenwood wants fifty doars for (in the continuing Kenwood tradition) a terriby organized, incompete, and horribe reading manua!!! We, I dug into the schematics and opened up the the radio, here's a ist of items that might be of interest to some: RF Board Contros VR - RX BAL VR - TX BIAS VR - TX BAL VR - TYP (50W output power adjust, used with S1 beow) VR - MIN (?????) / interna antenna tuner VR - TUN (Tune mode power adjust) VR - VSF (THIS IS THE 100W POWER OUTPUT CONTROL) VR - SWR Protect activation

3 Seite 3 von 35 VR - PWM (Forward power meter caibration) VR1 - RWM (Refected power meter caibration) VR1 - AL0 (ALC meter zero) VR1 - ALM (ALC meter caibration) VR1 - CPM (Processor meter caibration) VR1 - ALG (ALC gain adjustment) S - A Band Power Down Switch (Decreases power to 50 watts) IF Board Contros VR - VR - VR - VR - Beep voume VR - Sidetone voume VR - Processor adjust VR -????? VR8 & VR9 -????? VR1 -????? VR1 - VR12 & VR13 - S Meter adjust VR14 & VR15 - AGC adjust VR1 - Notch fiter adjust PLEASE NOTE! Most of these contros are 1/8" pots, so if you intend to adjust them use a VERY SMALL non-metaic too. My 850S aso came out of the box with the RIT/XIT contro not dis- paying 0.00 khz at fiducia (12 o'cock position) center. Behind the front pane in the upper right corner is the contro for center adjust. It just needed a wee bit of tweaking... Aong with this contro on the circuit board are the master adjust- ments for the SSB sope tuning (High Cut and Low Cut). When both top and bottom covers are removed, on the eft-hand side is the FM board. There are 3 (three) pots on the board. They are FM Wide (12khz) deviation, FM Narrow (6khz) deviation, and FM Mic gain. FM mode defauts to WIDE (12khz). This is WAY too wide for accessing any 10m repeater. Hit the 455khz fiter button again for FM-N (narrow). This wi set the IF to 6khz width, and you be abe to work FM 10m stations. Note: The 8.83 fiters are NOT seectabe in FM mode. Memory scroing via M CH./VFO CH. You can bypass a unused channes if you press the 1 mhz button. With the button active, ony stored memory channes wi be dispayed as the knob is rotated. Tuneabe memories. Out of the box, the radio is set up for non- tuneabe memories. Just bring up setup function xx on the dispay, and set it to ON, and ALL memories can be tuned via the VFO. When use the M.CH/VFO CH. switch you wi be returned to the origina frequency & mode setting in the memory. It may or may not be obvious to some, but the radio is capabe of cross-band and/or cross-mode operation. Just pump the required modes and frequencies into memory channes or VFOs, and you're off and running. Hope you have a very broadbanded antenna! CW message storage is ost when you power off the radio. I didn't order the DRU-2 option (yet), so I don't know whether these messages wi be saved. You'd think that with everything ese that is stored in RAM and backed up by battery, that Kenwood woud have made pro- visions to keep recorded messages aive aso. A modification???? When adding additiona fiters, is is necessary to set the corresponding switch on. Under the hatch on top, is a 4 position dip switch. The manua shows a picture of it, but makes no mention of their settings. This switch is necessary to inform the microprocessor of the fiters' absence or presence. ON is for presence, OFF is for absence. Beow is the switch diagram:

4 Seite 4 von = <-- YK-88C-1, YK-88CN-1, YK-88SN-1 = <-- YK-88CN-1, YK-88CN-1, YK-88SN-1 = <-- No Function = <-- YG-455C-1 or YG-455CN O O N F F I received the DRU-2, voice recording unit this week, and instaed it.here's what I found: The unit comes witè a ithium battery for backing up the voice messages when tèe rig is powered off. The initia state of the DRU-2 is: Message 1-8 seconds Message 2-8 seconds Message 3-16 seconds You can have the samping rate via front pane setup contro xx. This wi effectivey DOUBLE the time of of each message, however, the quaity of voice repro- duction wi suffer because of the ower samping rate. On payback of the messages, the microphone IS NOT disabed, so be quiet when you're transmitting stored messages. Use the MONI function to hear what you've recorded and/or are transmitting, and tèe MIC gain contro to keep the ALC in range, as the DRU-2 drives the radio much harder than the microphone input. The high boost function and speech processor are avaiabe to the DRU-2 during transmit. I aso got the VS-2 voice unit. The voice is the same as the oder VS-1 for the TS-440, and TS-940, but the unit is in a smaer package. It wi speak the frequency in either Engish or Jápanese. There is a voume contro pot on the bottom of the board whécè shoud be adjusted PRIOR to screwing down the VS-2. The output on my unit was very ow, unti I tweaked it up. Aso there are jumpers on the board to speed up the voice payback... You' need to consut the instruction page for the VS-1 for speeds, as there is nothing mentioned in the instructions for the VS-2. A note on output power of the rig. The radio uses 2SC2789's... These devices are rated as 100 watt devices Kenwood is running the finas VERY conservativey. When paying around with output, I had the rig dead-keying 175 watts, but backed it down to 100 watts, as I didn't want to bow up the rig, but I was äefinitey smiing as the Birds' meter swung with a 250 watt sug! The ROM chip on the digita board is socketed. Kenwood had probems witè eary 440's and 940's with poor sodered connections. Whie it's a nice idea to aow remova and repacement of the ROM to add features/fix bugs, this might become a probem area in the future. Hidden function!!! If you turn on the radio whie hoding down the VOICE button, EVERY button on the radio wi acknowedge its function via morse code! This is a terrific feature for sightess hams! I can't understand why it is not mentioned in the owners manua or marketing iterature! This modification has been read 7038 times TS-850S A band transmit

5 Seite 5 von 35 Kenwood markets this radio wordwide, and has made orovisions to aow the radio to transmit between mhz and mhz. I am providing this modification for INFORMATIONAL PURPOSES ONLY! DO NOT TRANSMIT OUT OF BAND, THIS WILL JEAPORDIZE YOUR LICENSE, AND HAVE THE FCC, AND/OR INTERNATIONÁL AUTHORITIES KNOCKING AT YOUR DOOR!!! The A-band transmit modificatéon requires the remova and re- ocation of a diode on the the digita board which is ocated behind the front pane. The US version of the radio has diode D11 instaed, and diode D9 removed. D11 must be removed, and instaed in the D9 position. This modification IS NOT for the faint of heart, as it entais removing the front pane, and the digita board. Note that the digitá board has soder hoes thát are throughsodered; that is, there are circuit traces on both sides of the board, so make sure that ALL soder is removed from the hoes. This modification wi aso aow the antenna tuner to tune anywhere the receiver is tuned. This modification shoud ONLY be performed ây those famiiar with sodering and de-sodering techniques, and requires patience, and dexterity. Thanks to Bi K0ZL for this picture. Date: User comment From: Max VE3TMT Subject: Diode not needed in D position On some TS850's it is not neccesary to insta a diode in the D9 spot. Cip D11 (the one on the right end) and check for proper resuts first. On my TS850 it worked without putting a

6 Seite 6 von 35 diode in D9. Date: User comment From: Jaye Subject: Fu TX on the Kenwood TS-850s I have recenty preform the modifcation on the TS-850s for fu TX, i have to coment that i did'nt have any dramas with this procedure,but!where it expanes to remove the diode D- 11 then repace in the D-9 postion this is not nessary, just cip D-11 and you wi aso have remove diode D-12 that is in parae series on the back of the digita board, this requires removing the hoe digita board to gain access to Diode D-12, aso wi coment that the board is not easy removed, due to the funny ooking screws which kenwood have paced on the board(you wi need a specia too or some smart thinking) in regards to the D-9 diode??? no go on this rig! and yes it wasn't to hard!,actuay had 3 stubbies of VB (Beer) then i was back on the air, best of uck Jaye,your Mate Down Under. :-)) Date: User comment From: Fred - G0 AOJ Subject: TS850 TX Modification I performed the wide TX modification some time ago, athough it is a bit trickey a I did was snip one eg of D11 diode ocated on the digita board and it worked. Be carefu not to pu any of the ribbon type cabes off when titing the front pane forward as I managed to do and I needed the hands of of 2 year od to get it back but I manged it...!! This modification has been read 8789 times TS-850S Broadcast Band Sensitivity BCB sensitivity REALLY suffers as a 24db attenuator is inserted when band-switched. This attenuator circuit is very simiiar to the TS-430/440. Possibe modification? This modification has been read 5392 times TS-850S Additiona Front Pane Functions Pressing SCAN + TX-M.CH wi set the radio into its extended function mode. These options can be scroed via the M.CH/VFO CH. switch. The foowing are the extended functions: 00 - This is the ROM Cèecksum dispayed as a 4-digit hexadecima number This cannot be changed Aow fiter seection in transmit. Initiay set OFF Antenna tuner power down. Initiay set to OFF Antenna tuner non-stop mode. When set to on, the antenna tuner wi not stop when the owest VSWR is found. Initiay set to OFF.

7 Seite 7 von Store mode, and fiter settings prior to changing bands, or cèannes. Initiay set to ON Dispay -HELLO- on digitia dispay, anä send it in Morse code on power up. Initiay set OFF Turn fu LCD dispay ON on power on. Initiay set OFF Turn Subtone ON or OFF. Initiáy set ON. Note tèat even when set off, the TONE indicator wi be it on the dispay Unknown. Initiay set OFF. This modification has been read 6902 times Step by step instructions to disabe the broadcast band attenuation for TS-850S This mod greaty improves the sensitivity and ikewise the reception on the AM broadcast band. No noticabe unwanted side effects have occured foowing this procedure. I ive within three mies of a 5,000 watt broadcast station on 1150 kc's and am abe to isten to stations on either side of that station. There is some spatter but using the notch fiter and the attenuation on the front of the radio takes care of that for the most part. This is *NOT* compicated and can be done in fifteen minutes. Ony one caution here: you WILL BE SOLDERING TWO POINTS ON A CIRCUIT BOARD THAT IS LOADED WITH SURFACE MOUNTED COMPONENTS!!! There is itte room to work on the board, so be very carefu with your iron! If you don't fee comfortabe sodering, get someone ese to do it as you can cause a soder bridge and ruin your radio without even trying. With that in mind, here goes: 1. remove the eeven screws that secure the bottom cover to the rig. the six ones on the sides and the five on the bottom cover itsef. 2. remove the bottom cover. there are no wires attached to the cover. ift it right off. eave the top cover of the radio ON. 3. ocate the RF BOARD. it's number is: X this is the board where you pug the optiona fiters into. with the open radio in front of you, and the front of the radio facing you, the RF BOARD is the one on the eft. (there are ony two boards under the bottom cover) 4. ocate the chrome ike shied on the rear of the RF BOARD. it's made out of shiney stee. remove the four screws that hod this shied to the board. 5. remove the shied by ifting the front of it up whie siding it forwards, towards you. watch out for a the itte wires and ribbon cabes going to and from the RF BOARD. 6. ook at the rear of the board and towards the eft corner.(the radio is sti facing you upside down) notice two I/C's numbered IC1 and IC2. directy behind the I/C's are a bank of adjustabe cois in meta cans. there are nine of these cois in a group. directy to the eft of these cois are many green and red inductors which are standing up. they ook ike resistors but they're reay sma cois. 7. these inductors are part of the bandpass fitering for each of the bands on the radio. the capacitors and resistors that compete the bandpass fitering are on the other side of the board and are of the surface mount type. you are ony concerned with the bandpass fiter for the.5 to 1.6 band. notice the numbers for the inductors. find L8 and L9. they are right at the edge of the board in the eft rear corner you wi notice that.5

8 Seite 8 von is stamped right next to L9. BINGO! you have found the part of the circuit that you wi modify. 8. ook at where the is stamped on the board next to L9. you wi see two bronze or god soder points there directy next to the numbers there is nothing sodered at those two points. this is where you wi soder a jumper wire between the bronze points. do NOT confuse it with the other two soder points with the ine running in between them next to the phiips head screw!!! you want the two points that are spaced very cose together that is right next to L9. 9. you wi have to do the sodering on the OTHER SIDE OF THE BOARD. remove the nine phiips head screws that hod the RF BOARD to the chasis. 10. on the back of the radio, ook for the switch stamped SW 1. it's right beow the grounding post and has the two postions: INT and EXT. remove the two screws that hod the switch to the back of the rig. the switch is sodered to the RF BOARD and you wont be abe to ift the board up unti the screws are removed. 11. unpug enough cabes from the board so you' have enough room to ift the RF BOARD up to soder the jumper. there is no need to remove the board from the rig. side it towards the front of the rig unti the switch SW 1 cears the back of the rig and ift the eft side of the board up and prop it up with a sma bock of wood. 12. ocate the bronze soder points on the underside of the board. there wi be a sma amount of soder at these two points on the underside of the board. 13. bend a sma jumper out of wire that fits the two bronze points on top of the RF BOARD. you wi pace the jumper on the top and soder on the underside of the board. with a pair of neede nosed piers, pace the jumper into the hoes and simpy heat up the existing soder on the underside unti the jumper sips down farther into the hoes. you' notice the arge amount of components on the underside versus the ack of components on the top of the board. be carefu when heating the soder on the two points. you don'y want to disturb the surface mounted parts or cause any excess soder to run onto them or the foi nearby. 14. you are now done. re-assembe in reverse order, pugging the wires back in carefuy, making sure they don't get pugged into the wrong pace. aso, avoid pinching them when repacing covers. X 4 L8 4 O O O O O O COIL BANK O O O O O O 3.5 o inductors 1 O O O O O O o 0 ic1 ic soder 0 point RF BOARD soder point L9 this area for optiona pug in fiters FRONT OF RADIO

9 Seite 9 von 35 Sorry, that's the best art work I can do. The purpose of the jumper is to bypass the two 150 ohm resistors that are in series after the bandpass fiter. The resistors add between 20 and 25 db attenuation to the AM broadcast band. For some reason, Kenwood thinks that the receiver woud become overoaded by strong nearby broadcasting stations, which woud cause distortion. I simpy don't find that to be the case. It's funny, Kenwood aready had those two points there on the board, but without the jumper...it seems to me that they had anticipated the need to bypass the attenuation in Europe or Asia. Thus, a export modes going to the states were missing that jumper. Who knows? I can't find any other reason for the jumper points to be there. Anyway, you' notice an immediate increase of signa strength. You' hear stations that you never knew were there! As I said, if you are bothered by strong stations in your area, try using the 6 and/or 12db attenuation buttons on the front of the rig. This modification has been read 5268 times TS-850? ACC-2 audio probem Foowing buetin was sent to me by Dick, KB8DB: KENWOOD/KAM SSB AUDIO PROBLEM The probem is that some kenwood radios are being shipped with the rear pane audio output very sensitive. We (kantronics) have had others report the same probem, and the foowing response was prepared by our service department: Some adjustments in the radio and in the kam may be necessary when using these connections. SOLUTION: Decrease the gain in the kenwood radio rear pane audio input circuit (may be abeed vr18, check your radio manua). Increase the afsk output from the kam (remove jumper k5 for maximum output). Set the kam to transmit in rtty mode, and radio in ssb mode, adjust vr18 (or gain contro in radio that contros rear pane audio input) for the radio manufacturer's recommended output when using rtty. Now, when using the front pane microphone, ow-eve noise on the rear pane input wi not be picked up or added to microphone audio. (unquote) 73 from Stan GB7BEN.#43.GBR.EU This modification has been read 5144 times Adjustabe moni. on CW, TS-850S Heo everybody! If you'd ike to be abe to adjust the voume with your "MONI-knob" on the frontpane of your TS-850S when monitoring your transmission on CW read this! Originay it's a fixed eve

10 Seite 10 von 35 controed by VR5 internay. This coud be usefu when switching between the oudspeaker and the headphones. When you're monitoring your CW with headphones at a peasent eve, and then disconnect the headphones and monitoring with the oudspeaker the audio is quite ow. (IF-UNIT) Remove the IF-UNIT (you must soder on the rear side of the IF-UNIT). Be carefu to mark a the cabes before you remove them!!! Remove R239 (330 kohm, cose to VR5). Insta a new resistor (330 kohm) from the output of VR5 to the junction R229, R230, R231 and C172 (rear side of the IF-UNIT, cose to IC7). Adjust VR5 to maximum audio eve. Now you're abe to adjust your audio eve in the CW mode with the "MONI-knob" at the frontpane of your transeiver. Gif fie of the circuit board ayout (445 Kb) where the mod is to be done in the radio. 73 de Nate Bargmann Packet: WF0A.#SCKS.KS.USA.NOAM E-mai: ka0rny@midusa.net Vaey Center, Kansas USA EM17hs Visit my Linux + Ham Radio pages homepage.netspaceonine.com/~ka0rny/ This modification has been read 4927 times TS-850 service manua, error corection Page 20: 2 Fu break-in operation timing signa enters pin 10 of the BW-SW modue from the... shoud be...signa enters pin 10 of the BK-IN modue from the... Page 21: Resistor R3 (10 kohm) in the BK-SW schematic does not exist. (This is corrected in the schematic that's in the user's manua) Page 23: Key up In ine 8 and 10 capacitor C230 is mentioned -shoud be C231

11 Seite 11 von 35 This modification has been read 5470 times TS-850S and speaker/headph This is a very simpe modification on the TS-850S to be abe to hear the receiving station through the oudspeaker and the headphones at the same time. On ICOM rigs it does not require any modification at a as this is a feature buit-in from the factory. On ICOM rigs if you push the connector hafway into the headphone jack you have the sound in both the oudspeaker and the headphones, then if you push the pug the whoe way in, the sound is ony in the headphones. Unfortunay this is not the case on the TS-850S. The headphone jack is a itte different made on Kenwood rigs, so this modification does not aow you this "hafway" feature described above. But sti you are abe to have the sound comming from the oudspeaker and the headphones at the same time. Modification. Note! This modification works on both mono and stereo headphones. 1. Remove a knobs at the front of the radio. 2. Remove the front. 3. Remove the very sma unit (E/6 page 57) that contains the phone jack itsef. 4. Insta a jumper between pin no. 1 and pin no. 2 on the CN8 connector. This modification has been read 5195 times TS-850 and Ten-Tec Titan 425 PA If you're using the Kenwood TS-850S with the Ten-Tec Titan 425 inear PA read this! This expains how to modify the TS-850S' fu QSK feature and avoiding "hot switching" the reay in the ampifier when operating fu QSK. As you probaby know the correct way to prevent "hot switching" is to feed a signa to the Titan's "key-in" connector when you transmit. When the inear's vacuum-reay is setted the Titan's "key-out" connector return that information to the transceiver which then feed its output RF to the inear. What's important here is that the transceiver DOES NOT feed any RF BEFORE the vacuumreay in the inear is setted! (If you do, you have the probem caed "hot switching") This is how to overcome the "hot switching" probem:

12 Seite 12 von 35 Open the TS-850 and do the foowing: 1. Remove the origina TRX-reay (K3 at the RF unit). 2. Remove the IF unit. 3. Locate the BK-SW unit (X ). Cut between Q2's coector and pin 10 on the BK-SW unit. Feed Q2's coector to the "key-in" on the Titan inear. Feed pin 10 (where you cut) on the BK-SW unit to the "key-out" on the Titan inear. 4. Reinsta the IF-unit. That's a! I connected the coector of Q2 to pin #4 on the REMOTE connector and pin #10 on the BK- SW unit to pin #2 on the REMOTE connector at the rear of the transceiver where you originay connect the keying of an ampifier. That's why you shoud remove the TRX-reay (K3) as described in point no. 1. Pin 4 on the remote connector shoud now be connected to the "key-in" on the Titan ampifier Pin 2 on the remote connector shoud now be connected to the "key-out" on the Titan inear. ONLY use shieded cabes!!! This modification works fine on my TS-850. I am abe to operate fu QSK at the maximum speed on the buit-in keyer unit without risking any damage to the vacuum-reay in the Titan at fu output power (1600W). This modification has been read 4797 times KAM-PLUS Probems!! with TS-450 & 850 Heo A,, A common probem when using a KAM-Pus mutimode with the Kenwood TS-850 or TS-450 occurs when the KAM-Pus is couped to the Accessory-2 socket on the back of the transceiver, producing noticabe distortion of the transmitted audio when using the microphone in SSB mode.. The probem is easy to cure by disconnecting the Accessory-2 pug from the back of the tranceiver, but this meant moving the transceiver around every time one wished to operate on SSB.. The probem is caused by the input sensitivity of the rear Accessory-2 socket being set to high, so that it picks up very ow eve noise from the KAM-Pus and associated computer wiring, this mixes with the microphone signa, to produce the distortion. The cure is to reduce the input sensitivity of the radio, thus reducing the chance of distortion, aso it goes without saying that the output from the KAM-Pus must be increased to compensate for this. With both the TS-450 and TS-850, adjusting the input sensitivity is straight forward and the transceiver manuas show you the appropriate contro and its ocation.. This is in both cases

13 Seite 13 von 35 VR18 to be found on the main board of the radio,(refer to manua) in practice I found that it was best to adjust this contro fuy countercockwise.. Then we need to adjust the output from the KAM-Pus by varying potentiometer R28 and setting removabe ink (K9), this ink is factory set on one post ony, (in the open position)!! this shoud be connected shorting the two posts, thus putting the KAM-Pus into the high output position, and then potentiometer R-28 is adjusted to give fu power out from your HF radio with very itte ALC defection, when the MIC gain is in the norma operating position.. Then I am sure you wi find that your probem is over, you can now simpy change from digita modes to SSB.. Remember if you have your Beacon activated to turn it OFF or it coud cause a few comments when operating SSB.. This modification has been read 4697 times TS-450,TS-850 feedback,acc-2 Conn Hi if you are using the ACC-2 connector to interface with your muti-mode controer, you may have had a probem with your transmitted audio signa being distorted, to eiminate this see beow. 1. Set your meter on the radio to read ALC 2. PK232 OWNERS: if asso using a VHF tranceiver, adjust the AFSK eve for proper VHF operation as expaained in chapter 3 of the operating manua.if not adjust for proper SSB operation. DSP / DSP Owners: Adjust the appropriate AFSK eve contro for proper SSB operation as expained in chapter 3 of the operating manua. 3. Pace the TNC in caibrate mode and press K to key the radio. 4. Adjust VR-13 on the TS-450 or VR-18 on the TS-850 so that the meter "Just comes off the peg" as described in the section tited "SSB Tranciever Fina Adjustments" (in the TNC operating manua). 5. Press Q to quit the CALIBRATE mode This modification shoud not affect any of the other norma operations of the radio.. Copy of service buetin from AEA This modification has been read 4824 times Modification for Externa keying, whie using the interna keyer Author: N7EX (ex-n0dh), Dave Henderson One of the minor draw backs to the TS-850 as a CW contest machine is the inabiity to use the interna keyer in conjunction with an externa keying circuit such as a persona computer or auxiiary memory keyer. As designed you must manuay throw a switch from interna to

14 Seite 14 von 35 externa keying to switch between one or the other. To make matters even more inconvenient this switch is on the back of the unit and is not readiy accessibe during norma operation. Simpy said this modification invoves running a new keying ine from the junction of S1 and D51 on the IF Board. For convenience this additiona keying ine can be wired to the DSP1 and/or DSP2 RCA phono jacks if you do not use the externa DSP unit. The modification to the unit to resove this probem takes ess than 30 minutes to accompish and can be done without "permanenty" modifying the unit which woud detract from its future resae vaue. If you don't use the externa DSP unit then the two RCA phono jacks marked DSP1 and DSP2 can be used as additiona keying input jacks as wi be outined beow. If you use the externa DSP unit then the modification can sti be accompished by running the externa keying ine out on a "pigtai." I highy recommend the purchase of a service manua which wi greaty improve your abiity to indentify the circuit points invoved in the modification. Considering that the radio costs $1500 what's another $30 to keep from messing it up! By the way compared to the two TS-930's that I nursed through the 80's, this radio is a breeze to troube shoot and repair which I have had to do twice through no faut of Kenwood (ong stupid story ~8>). From here you proceed at your own risk, if you fry the radio DON'T CALL ME. A precision ow wattage soder penci for doing surface mount sodering is recommended, If a you have is a 150 watt Weer soder gun then read no farther your better off taking the unit to an expert rather than "met" the circuit traces. I assume no risk for the accuracy or competeness of the encosed information. A yee who enter here embrace a hope for you may ikey have a better contest radio when you are done. 1. Turn the unit upside down with the back of the TS-850 toward you. 2. Remove the bottom cover. 3. In this position the IF board is on your eft. 4. Remove a the screws hoding the IF board to the chassis. (put them in a jar or something for safe keeping). 5. Unpug enough of the cabing to aow you to tit the board up so that you can access the bottom side of the board underneath S1 the "Externa/Interna" keying switch. 6. On the bottom side of the board directy underneath S1 you wi see 6 soder pads arranged in two rows of three pads each. 7. The midde pad on S1 nearest the back of the radio shoud be GROUND, soder the braid of an approximatey 9 inch piece of sma audio stye shieded cabe to this point, being carefu to dress the coax so as not to short to other circuitry. 8. The midde pad on S1 in the next row up of three pads is the keying ine. Soder the center of the shieded cabe to this point. 9. Route the other end of the shieded audio cabe through the chassis in the vicinity of the DSP jacks above. 10. Carefuy inspect a soder joints for shorts, etc. Repug the wire harnesses unpugged in step 5 above and reassembe the board to housing. Reassembe the bottom cover.

15 Seite 15 von Turn the unit over and remove the top cover. 12. Find the DSP input board with the three RCA phono jacks on it at the rear of the unit. The two DSP jacks are on the right when facing the rear of the unit. There are two connectors on this board (a 2pin and a 4pin). Unpug the 4 pin connector. Obtain another 4 pin connector and connect as foows (or directy soder to the underside of the board as foows) If you ony need one additiona CW jack then ground is pin 2 (coser to center of the radio)connect the braid of your new key ine to this pin. The input from the midde RCA phono pug is pin 1 connect the ceneter conductor to this pin. Like wise if you want two additiona CW jacks then do as above pus add a short between pins 1 and 3. If you want a sma RF choke or some ferrite beads on the center conductor of the audio cabe may prevent keying probems in high RF fied environments Cose the unit up and switch S1 to INTERNAL keying. You shoud now be abe to key the unit via the interna keyer (Via the standard key input jack) or with an externa keyer or computer via the od DSP jacks, without having to switch S1. This modification has been read 4676 times TS-850 Separate Receive Antenna Modification Author: Brian, WA3WJD Make a short oop of white tefon cabe with a mae and femae BNC connector. Loop it out of the back of the rig so just enough of the coax sticks out so the BNCs can be joined with a barre connector. Locate the itte header connector on the fiter board in the TS-850 that is on the receiver side of the TS850 antenna reay. Pu that connector oose. Spend a itte time tracking down mae and femae header connectors that match what Kenwood uses. Insta those on the ends of the white tefon coaxes sticking in the back of the radio. For norma use, just connect the BNCs with a barre connector and the rig is norma. For Beverage use, connect an extra antenna switch common and ant #1 to the BNC connectors, and put ur Beverages on the other positions. This modification has been read 5169 times TS-850 Separate RX antenna input mod Author: N6TR - n6tr@teeport.com.modification.net This is near the top of everyone's ist when they are asked "What things bug you about the TS-850S." I initiay overcame this deficiency by modifying my ampifier so I coud connect a

16 Seite 16 von 35 different receive antenna to the TR reay. However, I wanted to change things so there wasn't as much RF getting into the RX antenna due to cose proximity to the ampifier's output. This became a probem when using the same receive antenna on a second radio (you knew two radio contest operating was going to work its way in here somehow). Vie, OH2MM had provided me with instruction on how he modified his TS-850S to have a separate RX input and this inspired me to try it. Here are some simpe steps to hopefuy inspire others: It took me an unrushed two hours to do a this. 1. Remove the top pane (you don't need to take off the bottom one). 2. Remove the pate which sits between the fan and the back of the radio. This covers the output fiter PC board. 3. Unsoder the connections to the SO-239 output connector. 4. Remove the three cabes from the PC board next to the SO-239. This incudes two coax and one 3 conductor harness. 5. Remove the two screws hoding in the PC board and remove it. 6. Locate the trace that goes from the reay's normay cosed contact. You can use an ohm-meter to find it - probe from the wire that went to the SO-239. You wi find a short trace on the back of the board which runs to a chip capacitor. Cut this trace and soder some very sma coax to each side of the cut - connect ground to the nearby ground trace. Make the cabes about 4 inches ong. 7. Remove the antenna tuner. There are 2 screws in the back and front (you wi need a magnetic screw-driver) and one on the side. You wi need to carefuy unpug two wire harnesses and one coax connector. 8. Dri two hoes for phono jacks on the back of the radio. Be carefu not to obstruct the screw hoe for one of the screws in the back of the antenna tuner. The best pace is between the RF output connector and the groundpost. Put them on top of each other and as cose to the bump on the back pane as possibe. I used a vacuum ceaner whie driing to make sure no meta chips went anywhere. 9. You wi find a sma hoe under the SO-239 where you can feed the two coaxs through. Soder them to the phono jacks and reassembe everything. I put back to back diodes on the RX antennas input, but you may not want to do this. A better thing woud be to add a reay to disconnect the RX antenna input when transmitting. I took care of that in project # Obviousy, you wi need a jumper cabe to make your receiver work again. This modification has been read 4923 times The switch box Parts ist:

17 Seite 17 von 35 4 position rotary switch DPDT 12 VDC reay 1 K Ohm pot (optiona) 12 phono jacks (or you can get by with 9) mini box for above and knobs. Camp diode for reay coi if not incuded in reay This box does two things: disconnects the receive antenna input when transmitting and aows seection of the transmitting antenna or one of three RX antennas when receiving. The pot can be used for RF attenuation if your rig doesn't have one. The reay gets controed by the PTT output from your rig that normay woud go to your ampifier. Then one set of the contacts is used to key your ampifier. Don't forget to put a diode across the coi of your reay if there isn't one internay. Otherwise, you wi have undesired arcing across the contacts of the reay in your radio. The other set of contacts disconnect the output of the rotary swtich when transmitting. The rotary switch seects either the signa coming from the transmitting antenna (from the TR reay in your rig) or one of three receiving antennas. I use two phono jacks per RX antenna so I can feed them to other boxes for other radios. I aso use two jacks for +12 vots so I can jumper power to another box. You can buid up one of these boxes in an hour or two. You can epoxy the reay to the mini box. If you want the pot there to act as an attenuator, I just hook it up ike you woud a voume contro: one end is ground, the other end goes to the output of the rotary switch and the wiper goes to the output. Use shieded cabe as much as possibe to avoid stray pickup. This modification has been read 5121 times Computer Interface for the TS-850, without using the IF- 232 Leve Converter By N6TR and possiby others, with zener idea added by K6LL. Note: This interface wi work with "TR," contest ogging software by N6TR. Cick here for inks to TR and other contest ogging software packages, incuding shareware. Computer Interface: 470 ohms DB9 PIN 3 (TXD) ----//// TS850 ACC 1 PIN 3 (RXD) (DB25 PIN 2) VOLT ZENER DIODE / / DB9 PIN 5 (GND) TS850 ACC 1 PIN 1 (GND) (DB25 PIN 7) DB9 PIN 2 (RXD) TS850 ACC 1 PIN 2 (TXD)

18 Seite 18 von 35 (DB25 PIN 3) TS850 ACC 1 PIN 4 (CTS) TS850 ACC 1 PIN 5 (RTS) This modification has been read 5734 times TS-850 Power Output Contro VR7 on the RF Board (bottom side of radio). 125 watts or so on cw is safe. Do not exceed 100 watts on SSB, since distortion wi broaden the transmitted signa. This modification has been read 6709 times TS-850 Leve Attenuator for DRU-2 payback audio Author: K6LL - k6@juno.com.modification.net 1. Remove the itte hatch on the top of the radio. 2. With the front of the radio facing you, find connector CN505. It is a five pin connector near the fiter DIP switches. The white wire on the eftmost termina carries the DRU audio output. 3. Cut the white wire and insert a 100K ohm micromini pot, shunted with a 220 pf capacitor. Adjust the pot unti DRU payback eve matches ive microphone eve. Dave Hachadorian, K6LL This modification has been read 4574 times TS850 + Transverter oder Preseektor Author: Werner Maier, DL4NER - d4ner@qs.net.modification.net Wenn man von hinten auf den TS850 schaut, ist rechts eine kompette Leiste mit Steckern (ACC, diverse Cinch (ALC etc..)) usw. Oben sind zwei Reihen und unten ist noch eine dritte Reihe. (da ist auch die Cinch IF-Out dabei, die origina (t. Manua) benutzt

19 Seite 19 von 35 werden sote. Mir persönich hat das mit den 12 Vot nicht gefaen; das Risiko für Transverter und Nachsetzer bei Ausfa der 12 Vot war mir zu groß! Genau dazwischen (oben 2 Reihen, unten 1 Reihe) ist rechts ein Patz von ca. 2cm hoch, 8cm Breit und 3 cm tief. da passen die benötigten 4 Cinchbuchsen (drvout, drv in, ant out, ant in) probemos hin. Diese muß man für den normaen KW- Betrieb nur außen mit Cinch-Cinch- Koaxkaben brücken. Da es sich um Kurzwee (d.h. f < 30MHz) handet, dürfte die auftretende Dämpfung vernachässigbar sein. Zudem gibt es dort in den Gehäusseverstrebungen IDEAL Patz zum Kabedurchführen, as ob es von Kenwood dafür vorgesehen wäre und aus Marketinggründen zugunsten des TS950 gestorben wäre. So schauts jedenfas für den Baster aus. Oder der Patz wurder einfach präventiv für Stecker freigehaten... wer weiß...? Vorgehensweise: 1.!!!!! OHNE GEWÄHR!!!!! 2. Boden und Decke abnehmen. 3. von oben: Fiterpatine (mitte) wegnehmen. 4. Gehäuserückseite abschrauben, PL-Buchse aböten (evt. sind hier mehr as zwei Hände hifreich!) 5. Anzeichnen, bohren, auf genügend Abstand zwischen den Cinch-Buchsen und Gehäuseverstrebungen achten. (ca. 16 mm Lochabastand reicht, damit man sich die Finger nicht kemmt, beim Betrieb hinterher wie z.b. Stecker ziehen...) Beschriften mit z.b. ANT out, IF in, DRV out, FINAL in (oder wie's beiebt). 6. Kabe auftrennen: von der IF-Patine (wenn das Gerät umgedreht wurde, vorne inks) gehen ziemich hinten an den Steckverbindungen nach hinten mitte unten zwei Kabe weg, CN1 und CN2 (weiss und Rot/Orange/Rostbraun). Die beiden Kabe sind im Bid zusätzich mit einem geben beschrifteten Kebeband gekennzeichnet. 7. Das eine führt direkt zur Antennenumschatpatine, wo auch die PL- Buchse angeötet ist. Auftrennen, Verängern und auf 2 der Cinchs egen. Das zweite führt direkt zur Fina-Unit (unter der Fiterpatine). Auftrennen und auf die Cinchs führen. 8. sind die Buchsen hinten RICHTIG beschriftet? und RICHTIG verbunden? Besser mehrfach prüfen, das Tei ist teuer! Ist die Beschriftung eindeutig?

20 Seite 20 von Zusammenbauen. Dabei ALLE Steckverbinder wieder stecken. Mögiche Fastricke sind vieeicht: Verbindung Fina-Unit-out -> Fiter-Unit-in? (muss geöst werden, um die Fiterunit auszubauen). PL-Buchse wieder angeötet? Lautsprecher wieder angesteckt? 10. Hinten brücken und as KW-TRX testen. Preseektor anstöpsen, testen. Transverter anstöpsen, testen. 11.!!!!! OHNE GEWAEHR!!!!! Das Schöne ist nun, daß man probemos einen Preseektor dazwischenschaten kann. Ebeneso probemos geht das mit Transverter- Betrieb, ohne Angst um Transverter und TRX haben zu müssen, fas ma die 12V Steuerspannung vom Transverter ausfät. (Lt. Aussagen eines Fachhänders nimmt dabei nicht nur der Transverter sonder auch der TS-850 gewatig Schaden.). Und: Die Signae nach Außen unterscheiden sich von der Origina-Kenwood- Schatung (- >Transverterbetrieb) nur dadurch, dass jeweis ein Reais weniger in der Kette iegt. Signa orignia modifiziert Vortei Nachtei 10m-RX Rückbau: (für Verkauf, fas gewüscht): Löcher:Kenwood-Aufkeber. Durchtrennte direkt zur Antennenbuchse 10m-DRV wird vor CN1 mittes Reais auf CN25 geschatet und von dort mittes im Gerät umzusteckender Brücke auf die IF-Out-Buchse geegt, die dann nicht mehr für ZF-Oszi geeignet ist. wird nach Antennenbuchse und RX/TX- Reais zugeführt. wird ohne Reais nach CN1 direkt aufgetrennt. Preseektor- Betrieb mögich. 1. Man muss nicht mehr mit 12 V schaten. 2. Wenn die DRV-Leitung aufgetrennt ist, sendet die Endstufe auch nicht. Ueberspannungsdiode wird umgangen. (Gewitter im Transverter? Dann ist eh' aes zu spät!) Löcher in der hinteren Abdeckung und ein "verbastetes" Gerät. Leitungen: Ersetzen durch originae Leitungen (gibts bestimmt für Ged bei Kenwood). 73 de Werner Maier, DL4NER emai: werner@mayn.de.modification.net Vie Spaß mit Preseektor oder Transwerter. Zugriffe Seit 9/97: Date: User comment From: Stefan DL6NCY Subject: Cinch vs BNC

21 Seite 21 von 35 Ich habe die Cinch-Buchsen aus stabiitätsgründen gegen BNC-Buchsen ausgetauscht. Nach einiger Zeit, und auch öfteren umstecken, schob sich der Inneneiter der Cinch-Buchse nach hinten, so daß der Stecker keinen Kontakt mehr hatte. Auch werden die Brücken nicht mehr so eicht veroren... Ansonsten funktioniert aes UFB wie oben beschrieben. vy 73/55 Stefan DL6NCY This modification has been read 4925 times TS-850S Distorted TX w/tnc connected Author: Kenwood Communication, inc. Service Buetin no (10 October 1992) We have received severa reports of distorted transmitter audio when using a TNC controer such as the AEA PK-232 or Kantronic KAM, etc. The symptom wi generay disappear if the transceiver and TNC units are powered from different sources. Cause: The audio output eve form the TNC is generay too high and causes overoad of the microphone ampifier circuit. In previous modes such as the TS-440S the incoming TNC audio was inserted after the microphone ampifier. With the TS-850S it is inserted before the microphone ampifier. Just moving the insertion point to the output of the circuit is satisfactory since the drive eve for FM packet is higher then that required for SSB. Procedure: 1. Add a 10 db attenuator to the PKD ine on the IF unit (X XX). This wi prevent overmoduation of the microphone input circuit. a. Change chip resistor R258 from 2.2 Kohm to 1 Kohm (RK73FB2A102J) b. Change chip resistor R260 from 220 to 330 ohms (RK73FB2A331J). 2. Add the foowing note to page 29 of the Instruction manua. 3. When adjusting for proper ALC eves with an AFSK RTTY termina or Packet TNC termina you shoud adjust VR-18 on the IF Unit for a reading simiar to the one shown in the accompanying diagram. Note: The transceiver and RTTY or TNC termina shoud use separate power suppies, in order to prevent RFI (Radio Frequency Interference). Caution: This modification requires sodering equipment rated for CMOS type circuits. It aso requires famiiarity with surface mount sodering techniques. If you do not have the proper equipment or knowedge do not attempt this modification yoursef. Seek quaified assistance.

22 Seite 22 von 35 Time required for this modification is ½ hour or ess. This modification has been read 4651 times TS-850S Low/no Receive sensitivity Author: Kenwood Communication, inc. Service Buetin no (22 January 1993) Symptom: Reports of ow or no receive sensitivity accompanied by a ack of audio from the speaker during CW or SSB modes might be caused by improper RXB votage eves. Norma RXB votage is +8 Vdc during receive and 0 Vdc during transmit. If you find approximatey + 2 Vdc during receive you might suspect a probem with a eaking diode, D31 on the RF unit (X ). Cause: D31 is used as the transmit switching diode. Leakage of this diode id most probaby caused by eectrostatic surge or discharges from the antenna. Parts required: D31, MI204 Procedure: A temporary cure for units that have aready been manufactured is to repace D31 with an MI204 diode. Future production radios wi change D31 to an LFB01 diode and incorporate a change in the printed circuit foi pattern to aow addition of a series diode. D103 (LFB01). Caution: This modification requires sodering equipment rated for CMOS type circuits. It aso requires famiiarity with surface mount sodering techniques. If you do not have the proper equipment or knowedge do not attempt this modification yoursef. Seek quaified assistance.

23 Seite 23 von 35 Time required for this modification is 15 minutes or ess. This modification has been read 5122 times TS-850S No audio from VS-2 Author: Kenwood Communication, inc. Service Buetin no (6 December 1993) Symptom: Severa have reported a probem with the Voice Synthesizer Unit VS-2 not voicing the frequency reiaby when the Voice button is depressed. This symptom is caused by a drop in the 5C votage from 5 Vdc to approximatey 4.5 Vdc when the VS-2 is connected. The foowing change wi correct this symptom. Parts required: Qty Description Od part No. New Part No Circuit desc µh Chip coi L L L501 Procedure: Change L501 from 220 µh to 47 µh on the RF unit (X C/4). Caution: This modification requires sodering equipment rated for CMOS type circuits. It aso requires famiiarity with surface mount sodering techniques. If you do not have the proper equipment or knowedge do not attempt this modification yoursef. Seek quaified assistance from your cosest Kenwood Service Center (Long Beach, CA, or Virginia Beach, VA). Time required for this modification is 30 minutes or ess.

24 Seite 24 von 35 This modification has been read 4547 times TS-850S Mixer FET change Author: Kenwood Communication, inc. Service Buetin no (28 March 1994) Symptom: Severa units were discovered during production by our QC department that experienced difficut when the transceiver was being adjusted for an S-1 reading on the S-meter. Countermeasure: Variations in the gain of the devices used for Q16 and Q17, the second mixers, on the RF unit (X ) appear to cause of this symptom. We, therefore, recommend repacing these two transistors with 2SK520(K43) devices. These devices have ower IDSS (Drain breakdown current), and therefore provide a greater conversion gain. As a resut the tota gain of the circuit is increased. Parts required: Qty Description Od part No. New Part No Circuit Description 2 Second Mixer FET 2SK520(K44) 2SK529(K43) Q16, Q17 Time required for this modification is 60 minutes or ess. This modification has been read 5212 times TS-850S "Cick noise" with NOTCH ON Author: Kenwood Communication, inc. Service Buetin no (28 March 1994) Symptom: When a strong signa of S-9 or greater is received at the antenna termina with the NOTCH circuit ON a "cicking" noise might be noticed. This is caused by excessive response in the AGC oop circuit. Countermeasure: The changes detaied beow wi add additiona deay to the AGC circuit and reduce or eiminate this tendency. Parts required: Qty Description Od part No. New Part No. Circuit Description 1 22 Kohm chip resistor RK73FB2A103J RK73FB2A223J R µf capacitor NA CQ92M1H474K NA

25 Seite 25 von 35 Caution: This modification requires sodering equipment rated for CMOS type circuits. It aso requires famiiarity with surface mount sodering techniques. If you do not have the proper equipment or knowedge do not attempt this modification yoursef. Seek quaified assistance from your cosest Kenwood Service Center (Long Beach, CA, or Virginia Beach, VA). Time required for this modification is 60 minutes or ess. This modification has been read 4843 times Fu transmit for the UK version of TS-850S Author: Pred - Q2_Kinani@btinternet.com.MODIFICATION.NET This mod concerns ony the UK kenwood TS-850S. On the circuit board behind the front pane ies a bank of diodes numbered D1-D11 a diodes are there except for diode D10 to unock the uk TS-850s to fu transmit. Just cut or remove diode D11. Perform fu cpu reset, when powering unit after modification for fu reset press and hod A=B whie turning on unit... Pred Thanks to Bi K0ZL for this picture.

26 Seite 26 von 35 Date: User comment From: Aan J. Masson, K6PSP Subject: Modifying the US version of the TS-850SAT. In my US version of the TS-850SAT there is a group of diode positions for D6-D11 on the digita board, with ony D6, D7 and D11 fitted. I cut one end of D11, reset the microprocessor, and it worked FB. Date: User comment From: Adrian Subject: 136 khz access? Is there a diode mod that aows LF transmit in the new 136khz band? This modification has been read 5527 times TS-850 2nd RX output mod Author: Gary G4iFB - G4iFB@Amsat.org.MODIFICATION.NET The rues for RSGB Nationa Fied Day aowed the use of a second receiver but (at east in

27 Seite 27 von 35 Restricted Section) just one antenna. The second receiver coud be used as a "spotter", for exampe to keep an ear on 28 MHz for sporadice openings, or to check whether there is sufficient activity on another band to justify a band-change. In the absence of a top-of-the-range transceiver with a second receiver buit-in, I was prompted to make foowing modification to my TS850 such that an externa receiver coud be connected to the singe antenna, yet be disconnected automaticay when the TS850 transmits. The modification is described in detai step-by-step beow, but first you wi need the foowing items: a sma ength (about 20cm) of miniature coaxia cabe, for exampe Mapin part number XR88V (note - the characteristic impedence of miniature coax is typicay 75 ohm giving a mis-match to the 50 ohm impedence of the rig and antenna system, but such a sma ength of cabe is required that there is no noticeabe effect in practice) a coaxia "ine" socket e.g. SO239, BNC or Being-Lee (again, the impedence mismatch caused by using 75 ohm connectors has a negibibe effect in practice); a fine-tipped sodering iron and muticore eectrica soder; a medium (e.g. number 2 ) cross-head (Phiips) screwdriver. NOTE: a modification such as this is iabe to void the manufacturer's warranty - proceed at your own risk. It aso invoves a fairy deicate sodering operation so DO NOT ATTEMPT THIS uness you are competent and confident at sodering. 1. Switch off the power and disconnect a externa eads to the rig. Cear a space on the tabe in which to work. 2. Remove the rig's top cover: a. Remove 11 cross-head screws (3 on each side, 2 front and rear on the top, and the ast one centray on the top pane - don't remove the 4 screws hoding the oudspeaker to the top pane!). Keep the screws safey in a container to one side. b. Carefuy ift the top cover unti you can reach the oudspeaker cabe - remove this by puing off the sma white pastic pug from the socket mounted on the printed circuit board under the oudspeaker. 3. It is probaby easiest to turn the radio so the rear pane is towards you. Remove the meta id from the TX output bandpass fiter unit in the midde at the rear of the TS850, with a back rubber section attached (which normay insuates it mechanicay from the top pane). There are 7 cross-head screws to remove. 4. Find the sma printed circuit board immediatey behind the rig's SO239 antenna connector. The back rectanguar reay on this board is the main TX/RX changeover reay. Remove this board from the radio: a. Carefuy disconnect the two coaxia cabes by puing out the miniature pushfit pugs from the board-mounted sockets, and pu out the white pastic pug connecting the contro wires to the board. b. Remove both mounting screws.

28 Seite 28 von 35 c. Unsoder the SO239 socket from the board - both inner and outer connectors need to be unsodered - and ift out the board. 5. This is the fiddiest part of the job - get hep now if you are not confident at sodering. Soder your short piece of miniature coax to the underside of the TX/RX reay board, in parae with the TS850 receiver output connector abeed "RAT CN6". The coax shoud preferaby exit to the rear of the board so that it wi pass directy through the TS850 rear pane when reassembed. The coax centre conductor shoud be sodered to the "RAT CN6" pin nearest to the sma coi abeed "L13", and the braid to the adjacent (centre) "RAT CN6" pin which is earthed. Check carefuy that the joints are good (shiny and cean), and that no soder bobs or fakes remain on the board. 6. Pass the free end of the new piece of miniature coax out through the gauze on the rear pane of the TS850 - you may need to enarge a hoe in the gauze sighty, but the coax shoud be a fairy tight fit. 7. Repace the TX/RX reay board in the radio, puing the miniature coax through the rear pane as you do so. Reconnect the board by reversing the instructions given in section 4 above - connect a three eads (two coax eads, one 3-wire ead - the pug is poarised such that it is ony possibe to connect it one way, namey with the red ead towards the 1k ohm vertica resistor) and don't forget to soder the SO239 back on to the board. Once again check that your soder joints are good and no wayward bobs of soder remain. 8. Repace the TX output bandpass fiter unit cover and its 7 screws. 9. Repace the rig's top cover, not forgetting to reconnect the oudspeaker ead to connector "CN507" on the sma circuit board connected to the front pane by a white ribbon cabe as you do so. Take care not to scratch the paint when repacing a 11 screws. 10. Fit the coaxia socket to the free end of the miniature coax. 11. Check the resuts. Reconnect the rig and turn it on. Confirm that it receives propery. Try transmitting briefy to check that the RF output eve is norma. 12. Connect an externa receiver using a coax patch ead between the new socket and the antenna socket on the receiver - NOTE: be especiay carefu if using a transceiver as the externa receiver that the second rig cannot transmit. Preferaby, disabe the transmitter competey. RF POWER ABOVE A FEW MILLIWATTS ACCIDENTALLY APPLIED TO THE EXTERNAL RECEIVER CONNECTOR WILL INSTANTLY BLOW THE TS850'S RX INPUT CIRCUITRY AS THERE IS NO PROTECTION IN CIRCUIT!!! We, that's it. Mod compete. Now a you have to do is figure out how to make use of two simutaneous receiver signas without getting totay confused! By the way, athough the externa receiver's antenna is automaticay disconnected when the TS850 transmits, there wi sti be penty of RF in the vicinity - it is probaby best to avoid tuning the externa receiver to the TS850's transmit frequency, possiby even the same band, or to use an externa band-pass fiter in the receive ine. Best of uck in the contest OM! 73 de Gary, G4iFB This mod is a copi from with permission from G4iFB. This modification has been read 5489 times.

29 Seite 29 von A Band Decoder for the Kenwood TS-850 HF-Transceiver Author: Win DK9IP - dk9ip@t-onine.de.modification.net by Winfried Krieg DK9IP/KH7CD (Apri 2001) The Kenwood TS-850 transceiver is sti quite popuar amongst DXers and contesters but this rig does not have a buid-in band decoder as most of the ICOM transceivers do. Especiay in a contest setup this feature woud be very hepfu for a quick band change. By studying the circuit diagram I discovered a way how to easiy add a band decoder to the TS-850. This can be done by using the band signas that contro the fiter unit and the buidin automatic antenna tuner. The circuit can be added without permanenty modifying the unit (i.e. driing hoes) if you foow my recommendations. The suppement requires no specia knowedge or the remova of circuit boards but you have to soder on a board and some care shoud be taken not to damage anything. From here you proceed on your own risk. Don t make me responsibe if you fry your radio. My circuit uses 9 miniature reais (12V DC, spst type) to drive any remote antenna switch. The reay contacts are switched to ground when active (see circuit diagram) but it s aso possibe to switch to +12V if needed. I didn t make a PC board ayout for this prototype yet. Components were sodered on a perforated construction board (size abt. 8.5cm x 5cm). The board was mounted under the removabe top cover with 3 screws. This space is reserved for the optiona VS-2 Voice Synthesizer which I don t use. To connect the band decoder board to the transceiver proceed as foows: Remove the transceiver top case Remove the shied cover of the fiter unit X (7 screws) On the fiter board ocate the 9 pads marked 10A, 28A, 25A, 7A, 21A, 18A, 4A, 14A and 2A between IC2 and connector CN4 (see picture). These pins are on +12V eve when the reated band is seected Soder 9 wires of a 10-wire fat ribbon cabe to the pads and connect to the corresponding inputs (33K resistors) on the band decoder board. The remaining wire is connected to +12V as suppy votage for the reais. Use a separate wire for ground connection

30 Seite 30 von 35 I used a DB9 femae connector for the reay output signas. The connector can be mounted by repacing the ACC4 connector which is provided for connecting the externa antenna tuner AT You won t need this connector with the buid-in automatic tuner. Just remove the ACC4 connector and push it back into the case. The DB9 connector is fixed without additiona screws by camping it between the rear pane and the meta supports. Proceed as foows: Loosen a screws of the rear pane. Remove the 3 screws that hod the RTTY/DSP1/DSP2 connector board Pace the DB9 connector in the center of the ACC4 mounting hoe. Fix the screws whie camping the DB9 connector as described above (see picture) Connect the DB9-pins to the reay outputs of the band decoder using fat ribbon cabe. Ground connection is made via the meta case of the DB9 connector. Remember to connect the case of the DB9-pug to ground. That s a. Repace shied cover and top case. Now you can drive any remote antenna switch with the reay outputs from this band decoder. This artice can aso be found at This modification has been read 4582 times TS850s ac probem Author: Adrian - adshar64@yahoo.com.modification.net A common ALC faut in the X DC-DC converter board causes TX output power to cyce up and down in reguar cyces due to ac votage variation. This is dependent on the power suppy votage and wi show up usuay under 13.5v or ess.

31 Seite 31 von 35 Instead of repacing the DC-DC converter board repace R2 and R3, 22kohm SMD resistors with a esser vaue. I used 13kohm SMD resistors with great resuts ;ie no power dropoff symptoms down to 9v suppy tested. Have heard of 18Kohm vaues used with good resuts too. regards Adrian 389 Date: User comment From: Keith Subject: DC-DC converter (X ) The faut is caused by Q3 (2SA1162Y) a germanium PNP going eaky. changing the resistors in the mutivibrator can give a fix but the faut wi eventuay return as Q3 dies competey. Either repace Q3 or a better soution is to repace Q3 with a BCW30 and change R4 to 100k. This modification has been read 2560 times Noise Banker Mod Kenwood TS-850 Author: Adrian - adshar64@yahoo.com.modification.net This mod soves the TS-850S noise banker probem in eiminating eectrica interference and makes the nb design the same as the ts940 which doesn't have this probem. Resuts are outstanding. For the sceptica; Its easy to reverse mod. The NB board reference is X and it is ocated directy under the radio speaker.remove the upper part of the cabinet and unpug the oud speaker. You wi have to remove 4 screws and unpug 3 connectors in order to extract the board. The picture here shows the board mods required.

32 Seite 32 von 35 The capacitors to isoate are C618 and C619 Regards Adrian This modification has been read 2197 times TS-850s noise banker mod Author: B&B Technica Services - bbtech1@comcast.net.modification.net Removing D618 and D619 on the noise banker portion of the RF unit (sma one, just under the power switch, front eft of radio) wi increase the effectiveness of the TS-850 noise bankers.

33 Seite 33 von 35 Bi and Bonnie Leahy K0ZL, KB0HTC Date: User comment From: DG2IAQ, Jochen Heiemann Subject: Remove capacitors - not diodes!! Heo, the printed text of B&B Tech is wrong as described to remove "D618/D619". For sure it must be "C618 and C619" (=capacitors, not diodes). The parts are correcty named on the picture, not in the text. But don't worry, you woud never find the diodes, named D618/D619, hihi. You can find the capacitors on a part of the "RF UNIT PCB". 73, Jochen (DG2IAQ) This modification has been read 773 times TS-850 fan speed modification Author: Bi, K0ZL - bbtech1@comcast.net.modification.net I worked up a fan speed mod for the TS-850S, for RTTY, AM, FM and other high-duty cyce ops Jumpering R601 on the Digita D unit wi increase the fan speed about 50 percent; noise increa Digita D unit is ocated right aongside the PA unit, under the fiter unit, accessed from the top

34 Seite 34 von 35 Carefuy unpug the ribbon connector at the back of the board, then the two-conductor pug at forget to remove the two cips hoding the tabs of the reguator chips to the casting. I use a sma togge switch on the back, so that fan speed can be returned to norma; it's so qu not need it uness operating in a church or ibrary, hi! This modification has been read 449 times.

35 Seite 35 von 35 Have you any tips, trick or modifications you can't find here, pease send a mai to me. Can't you find a modification, then don't e-mai me pease. A mododification that i have, is isted on this site.! Have you probem with then you can visit the support page. Start page