MAXPRO3+ High performance FM transmitter board

Transcription

1 PCS Electronics MAXPRO3+ High performance FM transmitter board MAX PRO 3+ replaces the innovative MAX PRO 3 and adds new hot features. MAX PRO 3+ is a direct result of many years of experience and development in the RF field. Innovative design provides for amazing unparalelled RF field immunity, making it easy to integrate into an enclosure with an integrated W amplifiers and use at various transmitter locations (system integrators will love this). It was developed to form the heart of various professional FM transmitters. Another feature for the system integrators is possibility to connect this unit to our SE4 DSP stereo encoder, making it possible to use the same LCD display unit to set Mono/Stereo operation, preemphasis, compressor/limiter settings and bass/treble. Let's not forget the adjustable built-in SWR protection and overheating protection. Another welcome new feature are the on-board DIP switches, making it possible to set frequency and use the unit without the LCD. Output power can be adjusted in 3 jumper-selected ways, via on-board potentiometer, LCD display or a trimmer. You can easily set the power required to driver your favourite amplifier of choice. Fig. 1: MAXPRO3+, amazing performance and versatility Technical specifications: - RF Output Power: 0 to 15 Watts (15W typ, 20W max., easily adjustable) - Output connector: BNC - Output Impedance: 50 Ohms - Frequency Range: MHz (44-54 or MHz version on request) - PLL Steps: 6.25KHz (12.5/25/50/100KHz possible) - Frequency stability: +/- 20Hz - Spurious/Harmonic rejection: Harmonics: -60dB, Spurious: -90dB - Power Supply: V/3A or car battery - Quartz Locked PLL Frequency Control - Ultra Stable, Ultra Clean Output - Out of Lock Power Down - No Expensive Test Equipment Required to setup - Audio performance: Less than 0.1% distortion, 20Hz-75KHz - RF output ruggedness: SWR protection - Polarity protection

2 Why is MAXPRO 3+ so great? - true wideband no-tune operation - high power (15W typ, 20W max) - extreme VCO isolation and RF field immunity (our exclusive innovative design) - directly supports our SE4 DSP stereo encoder via LCD MENU system - SWR and TEMP protection with adjustable sensitivity - operation with or without LCD display - power adjustment via LCD, trimmer or potentiometer - PLL unlock power down How is MAXPRO3+ better than MAXPRO3? - Minimal PLL step now 6.25KHz - Operation without LCD module now supported - Enhanced SWR/TEMP/PLL UNLOCK protection operation - Improved board layout - Improved heat sink Why is MAXPRO3+ better than MAXPRO4? - MAX PRO 3+; Minimal PLL step is a lot smaller (6.25KHz versus 50KHz) - MAX PRO 3+; Features better immunity for strong RF fields and is better suited for 500/1000W or more transmitters - MAX PRO 3+; Better SWR/TEMP/PLL UNLOCK protection operation - MAX PRO 3+; Possible operation without the LCD module 2

3 Figure 2: MAXPRO3+ board layout 3

4 DESCRIPTION OF VARIOUS ELEMENTS OF THE MAX PRO 3+ EXCITER BOARD! A. Power ON/OFF switch B. Power on indicator C. Output RF power adjustment, active when Jumper (L) in position P2 D. SWR/TEMP/PLL error LED. This LED is activated when RF output stage is NOT active. For example, whenever temperature protection is activated, this LED illuminates and RF power is reduced to zero. Important: This LED is also illuminated whenever you change frequency or power as the computer turns RF power off until adjustments are finished. This does not signal a problem with temperature or SWR. E. Pre-emphasis. Use this jumper to set pre-emphasis. This can either be 50uS (EU and most of the world) or 75uS (USA). If you plan to connect stereo encoder to the MAX PRO 3+ board, remove the jumper (this disables pre-emphasis). F. If you need to increase audio input sensitivity, put a short across this resistor (originally K). This will increase sensitivity of the audio input of the MAX PRO 3+ board, but you will no longer be able to use preemphasis (usually not important as this is handled by stereo encoder). G. Audio input sensitivity adjustment. H. Audio input - RCA jack. I. Overheating protection adjustment. Low setting means that the protection trips at low temperature. A setting of about 50% (middle) is recommended. Change, if necessary. Protection will disengage automatically when the temperature falls. Built-in hysteresis prevents oscillation near switch points. J. SWR protection adjustment. Low setting means that the protection trips very early, at a low SWR ration. A setting of about 30-50% (middle) is recommended. Change, if necessary. A poor antenna will trip this protection and transmitter will start powering down the output stage. Full power will be restored as soon as the SWR stops being too high. K. This potentiometer allows RF power adjustment, if you set the L jumper into position P3. Potentiometer is not installed as most people prefer LCD power adjustment. If you want to use one, insert standard 2K2 type. L. This jumper selects the means of RF output power adjustment. It can either be LCD, trimmer P2 or potentiometer P3. M. Soldering posts for a small 12V fan. Output stage appreciates a bit of air flow, it does not have to be substantial. As long as the air slowly moves a bit it'll be more than enough so use weakest available FAN. Some 24V fans run very slowly and quiet at 15V and would be ideal for this. N. Not to be used, for factory only O. Extension connector, not to be used at this time. P. LCD control unit. If you want to control this unit with LCD, attach your LCD control module here. Q. Do not touch unless you understand what this is. This lets you fine-tune the reference frequency. Can be used to set the unit to any frequency, even though the PLL step is 6.25KHz. You can for example use this to set the frequency to KHz by first using the LCD to set it to Hz and than using this trimmer to shift it to Hz. R. 3-wire cable to SE4 DSP+ stereo encoder. This lets you control both units from the same LCD control units. Most our Cyber Max FM units use this arrangement. S. 3A fast fuse. Always replace with this type for continued protection against short-circuit. T. Power supply connector, center is positive. DO NOT use more than 15V V is necessary to get full power. Z. Output stage quiescent current. DO NOT touch unless you know what you re doing or unless you own a power meter. You can use this to increase or decrease maximum available power. For example, you can set your transmitter to 15W with LCD control units and than use this trimmer to reduce maximum power to 4W or 1W. LCD will than control your output power from 0 to 1W or from 0 to 4W. Warning: This allows setting output power in excess of 20W. Damage may result so proceed with care. X. DIP switches. These switches let you set frequency without LCD control unit. If you want to use LCD control unit, set all DIP switches to OFF. If you leave any switch in ON position, transmitter assumes that you want to use DIP switches and ignores LCD module commands (generating I2C errors on the LCD). Y. Same as the above. Note, read the rest of the document for frequency tables. W. RF output connection. BNC jack. Use a properly matched FM band antenna. The range and success of your transmissions will depend primarily upon the quality and position of your antenna so invest your energy and money into a proper solution. 4

5 THANK YOU FOR PURCHASING THE MAXPRO3+ FM EXCITER! We hope you will enjoy it as much as we do and remember to tell your friends about it. Please feel free to leave your comments at our website or post your experience in our forum. From all of us we wish you happy broadcasting! PCS Electronics team BEFORE YOU START... Let us clear up some basic things you need to know before we move on. You will find some very useful tips, a forum and tips on antennas and hooking things together at so it's generally a good place to check before putting your MAX on the air. Here is what you need to get MAXPRO3+ on the air: Antenna Preferred type of antenna is affected by several factors, but mostly by your transmitting site. In the middle of the area you want to cover you'll need an omni-directional antenna which transmits equally in all directions, while outside your coverage area you can beam the signal in with a directional antenna. Before going on air get a low VSWR by adjusting the position of the antenna and any adjustable pieces. Aim for 2:1 or less. Use low power into the antenna when tuning it up and making adjustments. If you were using 100's of watts and a bit of the antenna came off in your hand the VSWR could be so bad as to blow the final transistor. For the same reason check the DC continuity of the antenna with an ohmmeter before plugging it in, to be sure it's what it's meant to be, either a short circuit or an open one, depending on the antenna type. For instructions regarding construction of antennas please see our website: (guides section). You should have realized by now that antenna was, is and will always be a crucial part of the system. Special care has to be taken! It is usually a good idea to place antenna away from your transmitter, power supply and A PIECE OF WIRE OR TV ANTENNA IS NOT SUITABLE ANTENNA FOR MAX PRO I OR ANY OTHER RADIO EXCITER! audio system. If you cannot meet these requirements, you could experience feedback and other RF problems. We cannot guarantee proper operation of MAXPRO3+ unless suitable antenna system is used! This applies to any transmitter. Interestingly, strong RF field can make CD players and other digital devices go bezerk. Try placing antenna next to yours and see what happens. Most of the modern audio gear is not RF shielded reducing costs is unfortunately the mantra today. This is why keeping antenna away from audio gear is a good idea. Coaxial cable Coaxial cable is an electrical cable consisting of a round, insulated conducting wire surrounded by a round, conducting sheath, usually surrounded by a final insulating layer. The cable is designed to carry a highfrequency or broadband signal, usually at radio frequencies. Coaxial Cabling is a two conductor closed transmission medium that is often used for the transmission of RF energy. It yields excellent performance at high frequencies and superior EMI control/shielding when compared to other types of copper cabling. Coaxial cabling is commonly found in broadcast and networking systems. Most coaxial cables have a characteristic impedance of either 50 or 75 ohms. The RF industry uses standard type-names for coaxial cables. The U.S military uses the RG-# or RG-#/U format (probably for "radio grade, universal", but other interpretations exist). The common RG-58 from Radio Shack is NOT the best you can do and will lower your effective power out! Use it only for short runs. BELDEN makes terrific coax in various qualities and with very low loss (measured in db s decibels). 3 db loss = 1/4 of your signal strength - either lost or gained. Watch out for the correct impedance RG-8 and RG-58 have 50 Ohms. RG-59 and RG-6 (Low Loss Version of RG-59) have 75 Ohms. Most antennas and transmitters including ours are 50 ohm. Check our website for good coax. Don't buy more than you need to make the long run to your antenna and don't make up a few "jumpers" to go between your exciter, VSWR meter and your antenna as all you'll do is create higher SWR and more line losses. H-155 or H500 are good choices! RG-142 with Teflon is recommended for wiring inside cabinets, for baluns, Wilkinson couplers and everywhere where resistance to heat is required as insulation won t melt during soldering or operation. 5

6 So what is this swr (vswr) everyone talks about? VSWR is a measure of how well two devices are impedance matched to each other. Typical radio equipment is designed for 50 ohm load impedance, so we usually use 50 ohm cables and build or buy antennas that are specified for 50 ohm. While most cables have flat impedance over frequency (they measure 50 ohm at all frequencies you are likely to use) the same is not true of the antennas. A 1.0:1 VSWR is a perfect match. That means the load impedance is exactly 50 ohms. A 2.0:1 VSWR is obtained when the load impedance is either 25 ohms or 100 ohms. Because most transmitters will deliver full power with a load VSWR of up to 2.0:1, this value is usually considered the limit for acceptable operation. Many prefer to keep their VSWR below that however, but for all practical purposes, it is unnecessary to spend time or money trying to get much below a VSWR of 1.5:1. The benefits will be hard to measure and even harder to notice. On the other hand, coaxial cable losses increase rapidly, for a given frequency of operation, when the antenna VSWR exceeds 2.0:1. This can even, in some extreme cases, result in the coaxial cable burning, even when running 100 W. Using a higher grade of cable will definitely improve things, but even high quality coaxial cable becomes very lossy when VSWR exceeds 3.0:1 at higher HF frequencies (or VHF and higher). BNC connector A connector comes between coaxial cable and your transmitter. It s a standard VHF RF connector for low power applications, just like the one used for Ethernet networks. You might get it along with your antenna. Try to find a good quality BNC connector as PC type usually uses cheap plastic instead of Teflon. The good ones are usually easily recognized by much higher prices. BNC to SO239 converters are available and will make it possible to connect PL259 (CB type or UHF) connector directly. Some of our units also use N connectors. Power supply You will need a good regulated volt, 3A regulated power supply. You can always use a lead acid car battery and re-charge it when you are off the air. HAM or CB power supply units do the job nicely in most cases. Poor power supply can add hum to your signal! MAXPRO3+ gives more output power when you increase the supply voltage. We have tested it up to 15V and had no problems, but we do not recommend using more than 15V. Of course too much voltage can fry your output transistor, especially if your antenna is not well matched. You can build your own power supply or get one from our website. Try our web site for schematics, if you want to make one by yourself. -Audio equipment For a start all you need is a simple CD player or a cassette deck. If you want that really professional sound, you will eventually need low noise audio mixer, good microphone and maybe as well audio Limiter-compressor. Behringer is a well known name for such equipment. Consider using a PC as your audio platform, get a good sound board and it will do mixing, MP3-playing, limiting, audio processing, CD-playing etc, all at a minimal cost (provided you already own a PC). -Stereo encoder If you want to transmit in stereo, you also need a stereo encoder. The cool thing about MaxPro3+ is that it directly supports SE4 DSP stereo encoder. This makes it possible to set all audio parameters easily via LCD control module. SE4 DSP+ comes with excellent DSP filters and 19KHz notch. When using other units look for good stereo separation, 19KHz notch filters, a limiter and balanced inputs, if possible. Balanced inputs are an instant cure for most noise problems and this is why all professional installations usually take advantage of balanced inputs. -Enclosure Use metal for your enclosures, allow some free space for future add-ons (stereo encoders etc.) and heat dissipation, and make ventilation holes at the top and/or back of the enclosure. Fix the PCB and heat-sink with all screws tightly. Flat cable should be wired away from the VCO assembly (L1). MAKE SURE YOU TIGHTLY SCREW THE RF BOARD TO THE ENCLOSURE AS THIS IS HOW THE OUTPUT TRANSISTOR DISSIPATES ITS HEAT! Finally, if you know nothing or little about electronics, we selected a few books we found extremely well written and useful. The links to them are on our homepage. We suggest you start with the ARRL HANDBOOK, the holy bible of amateur radio and electronics in general. It is an extremely valuable resource for every broadcaster. 6

7 ASSEMBLING THE MAXPRO3+ INTO AN ENCLOSURE Front panel 5mm LED cutoff pins Front panel Screw UP, DOWN & MENU PCB Display Contrast Display board and keys assembly Distancers Bolt Fig 3: Installing display board to the enclosure POWER UP Connect antenna (preferably dummy load for a start), SWR meter and power supply. Make sure power adjustment jumper (L) is set to desired setting. If you are using LCD control module, do not forget to set all DIP switches to OFF. Power up the unit/power WARNING: PLEASE BE SURE THAT YOU ARE TUNING IN TO AN AREA ON YOUR LOCAL FM BAND THAT HAS NO STATION BROADCASTING ON IT, YOU DO NOT WANT TO INTERRUPT ANYONE ELSE'S LISTENTING TO LOCAL RADIO STATIONS, IT'S RUDE AND ALSO ILEGAL! supply. Now you should see the welcome message on your LCD. You might need to adjust trimmer on the LCD to get good contrast. You will also hear a beep after power on. If all is OK, you can try to alter working frequency with UP/DOWN keys. Set output power to some comfortably low level for testing. Now turn on your MP3 player, CD audio player or other AUDIO source. Turn on any fm radio and turn the tuning dial until you hear the MAXPRO3+ s audio through the fm radio. You will need to adjust audio level so that the sound on the radio sounds natural and without distortion. Too much volume may sound good on your radio, but will sound horrible a few hundred meters from the transmitter! You shouldn t sound louder then other FM stations; rather you should sound a bit quieter since you re not using limiters/compressors (yet). When you sound as loud as other stations and you re not using audio processing, you re actually over modulating. Unfortunately many commercial stations over modulate nowadays, it s a sad fact. You may want to try a few different frequencies because of better reception in different areas. Some spots on the dial may work better than others. Now slowly increase the power and keep an eye on your SWR meter and transmitter board. If you see a problem, turn the unit off and eliminate its cause. Tune your antenna, if necessary. Do it at 1/3 of maximum power to protect the output transistor. MAXPRO3+ features SWR protection, but it is best not to ask for trouble. TROUBLESHOOTING We hope you ll never get to this step. We all know bad things happen. But do not despair! First, MAXPRO3+ is reverse polarity protected so it should blow a fuse if you reverse polarity. SWR and TEMP protection should help, too. If you have problems that you cannot solve yourself, please see our website for contact information and support resources in our forum. THINGS TO REMEMBER Please remember to turn off the transmitter when not in use! Remember that anything you broadcast through the transmitter can be heard by anyone tuning in to that frequency. Although it is unlikely certain weather conditions may allow the signal to go further than your immediate listening area so please don't broadcast anything you don't mind anyone else hearing. NEWSLETTER You may want to sign up for out newsletter so you can receive the latest news and special deals. Also check our forum and discuss tips and tricks with other users, you never know you just may learn something. You can sign up at 7

8 APPENDIX A: USING THE MAXPRO3+ Basically there are three push-buttons available for the menu system, UP, DOWN and MENU. By pushing UP or DOWN you get a shift of frequency in corresponding direction. Hold any of these keys for a few seconds and the jumps will increase to 500 KHz. The new frequency is saved automatically. The third button (MENU) gives you an option to set many of the DSP functions of this unit. LCD CONTROL MODULE MENU SYSTEM: POWER AND DSP FUNCTIONS It is possible to connect our SE4 DSP+ stereo encoder to MAX PRO 3+. The provided 3-pin header can be found on the RF board next to the LCD control unit s IDC-14 connector. Latest versions of MAXPRO3+ automatically detect SE4 DSP+ and enable all of the DSP functions. The UP and DOWN keys are used to change parameter value. In normal mode the LCD simply shows the frequency and power. Menu key can be used to enter the menu mode, repeatedly pressing this key brings up the following menus: POWER, TREBLE, BASS, COMPRESSION, THRESHOLD, ATTACK, DECAY, INTEGRATION INTERVAL, PREEMPHASIS and FREQ. SHIFT. Pressing the UP or DOWN key selects the desired parameter and allows you to modify its value. Another press on the MENU key and you re back to normal mode. FREQ. SHIFT Frequency can normally be adjusted in steps of 25KHz, even though the PLL actually allows steps of 6.25KHz. This was done since the user seldom needs such small steps. However, you can enter this menu and select a frequency shift of +6.25, or KHz and take advantage of these small steps. POWER This setting allows you to set output power of MAXPRO3+. Select desired power with the UP/DOWN keys and press MENU key to exit the menu system and return to normal operation. Selected power is continuously displayed on the LCD. This only works with the D/A boards. TREBLE and BASS This setting allows you to set amount of treble and BASS in your audio. Recommended value would be about 0dB. This function requires SE-4 stereo encoder. CYBER MAX FM 150W: Setting the treble, one of the many menu settings COMPRESSOR SETTINGS A number of MENU settings control the operation of the compressor. Lets assume that the audio signal enters the transmitter at some low level. Compressor does nothing to the signal until at one point as the input signal increases the signal reaches the compression threshold. Digital signal processor starts compressing the signal beyond that point. The higher the compression ratio the higher the compression. For example, compression ratio of 1: would in effect be a limiter. This function requires SE-4 stereo encoder. 8

9 Figure 5: Explanation of the compressor settings MAXPRO3+: Setting the compression level, levels between 1:2.00 to 1:4.00 are recommended MAXPRO3+: Setting the compression threshold, levels between 7 and 12dB are recommended MAXPRO3+: Setting the attack time, this is the time between the signal rise and the actual response of the compressor MAXPRO3+: Setting the decay time, this is the time the compressor needs to respond to a decrease of the signal 9

10 MAXPRO3+: Setting the integration interval, this is the time the DSP extracts the samples PRE-EMPHASIS It is possible to adjust the pre-emphasis of the transmitter to either 50uS (standard for EU and most of the world) or 75uS (United states and Canada). This function requires SE-4 stereo encoder. JUMPERS, CONTROLS AND TERMINALS Jumper Function Default setting J1 Audio input, 600 ohms J2 Pre-emphasis 75uS, 50uS or none J3 RF power adjustment method J5 Not used Positive in the center J6 LCD control module Do not reverse polarity by mistake! J7 Jumper for 3-pin cable to SE4 Stereo Encoder Enables control of SE4 DSP parameters via MAXPRO3+ LCD module J8 Small FAN Small slow 24V or 12V fan J9 +15V terminal for other units inside the box Handy 15V solder pad for stereo encoder or rds encoder J10 Supply voltage, center is positive J11 Antenna, 50 ohms, BNC F1 3-4A fuse, fast P1 Audio level Watch polarity, do not install backwards P2 Power adjustment Makes it possible to set power P3 Power adjustment Makes it possible to set power P4 Temperature protection About 50%, sets the temperature at which the transmitter starts switching off P5 SWR protection Sets SWR protection Q Reference oscillator adjustment For advanced users only, enables very precise adjustment down to 1Hz AUDIO LEVEL ADJUSTMENT Adjust audio level with trimmer (P1) on the RF board so that you sound a bit less loud than other radio stations. This prevents interference to adjacent channels as you probably do not own expensive audio equipment that radio stations usually employ to make their stations sound louder. Remember to disable pre-emphasis, if you re using a stereo encoder (usually a stereo encoder or limiter include their own pre-emphasis circuit). APPENDIX B: HOW CAN I INCREASE PERFORMANCE? I m pretty sure you are all interested in this, or at least you will be after a while. First let me warn you that some First and most important, the best thing you can ever do to increase performance is to get better antenna and/or move it higher! of you might have stability problems if you try to push MAX too far. You ll also have to account for additional heat. Here is a list of simple things you can do to raise output power of MAXPRO3+: 1. Increase supply voltage to 14-15V 2. Tune (compress or expand) L2, L3, L4, L5 for maximum power 3. Purchase a better antenna or an amplifier Any ideas and improvements are welcome, please let us know and we ll publish them on our home page. Some of them are already posted there. APPENDIX C: THE RESISTOR COLOR CODES The easiest method is to get radio Shack part number for $1.19; it is a pocket sized card with spin dials. Just spin the dials to show the correct colored bands and read the resistance off the card. Sort of a resistor slide rule. 10

11 Fig 10: Resistor colour codes, if there are only four bands, omit the 3 rd digit. APPENDIX D: GP ANTENNA DESIGN You can build an inexpensive 1/4 wave antenna from 1 so-239 chassis mount rf connector and 5-3' bronze welding rods, cut to the proper length. Here is how it looks: If you have a SWR meter, leave a bit longer radiator and adjust it later by cutting to achieve minimum SWR.»Do it yourself«gp antenna Most designs on the web don't compensate for the fact that GP antennas are not wideband antennas. Here is a Freq/element length chart for this simple GP antenna, all element lengths are in millimeters: For other antenna designs check our web site. Frequency Radiator - B Radials - A 108MHZ MHz MHz MHz

12 APPENDIX E: CONNECTING SE4 DSP+ TO MAX PRO 3+ This is a great idea as you can control all parameters through the same LCD unit. Below is the diagram, but we also recommend reading the I2C troubleshooting guide, which gives additional info. APPENDIX F: PROBLEMS REACHING THE TOP OF THE BAND AND PROBLEMS WITH LOW OUTPUT POWER Are you experiencing either lower than expected output power or can t cover the top of the FM band? These two problems usually have a similar cause, inadequate mains power supply. MAX PRO 3+ requires 13.8V-15V DC stabilized mains power supply capable of supplying at least 3A of continuous current for 24/7 operation. Using 12V or 13.8V DC power supply will effectively lower your output power when compared to our standard 15V DC power supply. If you still cannot reach the top of the band, locate L1 on the board (R), heat it up a little with soldering iron and push it inside the board just slightly, about 1mm should be enough. You should now be able to tune into any part of the FM band spectrum even with supply voltage as low as 11-12V. APPENDIX G: DISABLING THE PLL-UNLOCK POWER-DOWN FEATURE MAX PRO 3+ is equipped with the PLL UNLOCK POWER-DOWN function, meaning it will shut down the output stage if PLL looses its lock (VCO changes frequency). In some cases this may not be required or welcome, say perhaps you want to exceed modulation index far beyond the standard for testing or other purposes. In all such cases please follow the picture below. Keep in mind that you should not perform this unless you really know what you're doing. You could end up transmitting on a wrong frequency and cause interference to other stations. 12

13 APPENDIX H: IMPROVEMENT TIPS Think about purchasing SWR meter to tune and align your antenna. A good antenna system is extremely important and can make up for a lot of power. For a suitable SWR meter check: If you can t get much range with your homebrew antenna, have a look at these: Still not enough range? Well, how about a 300W amplifier? APPENDIX I: DIP SWITCH FREQUENCY TABLE NOTE: If you want to use DIP switches instead of the LCD display module to set power, remove LCD display module and set DIP switch to a desired value. The only forbidden setting is all switches to off. If you want to use LCD control module, set all DIP switches to OFF!! Publishing entire DIP switch / frequency list would mean 2 on the power of 12 = 4096 different values in the table, which would easily exceed 100 pages. We will try to reduce this to a more manageable size by describing the procedure and you ll be able to figure it out yourself easily. First, the small DIP switch (4 switches only) controls the last 2 frequency digits. 6.25KHz 12.5KHz 25KHz 50KHz Total KHz KHz KHz ,75KHz KHz ,25KHz ,5KHz ,75KHz KHz ,25KHz ,5KHz ,75KHz KHz ,25KHz ,5KHz Small dip switches start off at an odd value, reason is described below, read on. Second, the big DIP switch (8 switches) controls the other (big) frequency digits. See the large table below for a frequency list. Third, at the setting of (all switches to off) the frequency starts at ,750 Hz. Why is this? The setting of is reserved for LCD control module, as you know, so the first usable lowest setting is in fact (smallest dip switch 6.25KHz turned on). We have designated this setting to give Hz exactly. Knowing the above information it becomes very easy to calculate required setting for a given frequency. Let s say we want a frequency of MHz, we would start off by setting a value of 0KHz for the last two digits for the small 4-switch DIP. Look at the first table: 6.25KHz 12.5KHz 25KHz 50KHz Total KHz Now we need to setup the big 8-DIP switch so look at the big table below and look for 100 MHz. 12.8MHz 6.4MHz 3.2MHz 1.6MHz 0.8MHz 0.4MHz 0.2MHz 0.1MHz Frequency MHz Piece of cake, isn t it? 13

14 Below is a table for the large dip switches, in importance they go from 12.8MHz (see the PCB) down to 100KHz (0.1MHz). For example, if you want a frequency of 86MHz look below and set all 8 switches to 0 (off), than look at the small table for a value of 0KHz and set the smallest of the 4 switches to 1. Done! 12.8MHz 6.4MHz 3.2MHz 1.6MHz 0.8MHz 0.4MHz 0.2MHz 0.1MHz Frequency MHz , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,5 14

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16 , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,9 16

17 , , , , , , , , , So, do you think you can handle it? We think you sure can! 17

18 ALSO AVAILABLE FROM PCS ELECTRONICS Directional antennas, 5W boosters, stand-alone FM transmitters and much much more Check LIMITATION OF LIABILITY To the maximum extent permitted by applicable law, in no event shall PCS Electronics or its suppliers be liable for any special, incidental, indirect, or consequential damages whatsoever (including, without limitation, damages for loss of business profits, business interruption, loss of business information, or any other pecuniary loss) arising out of the use of or inability to use the PRODUCT, even if PCS Electronics has been advised of the possibility of such damages. In any case, PCS Electronics entire liability under any provision of this agreement shall be limited to the greater of the amount actually paid by you for the PRODUCT or U.S. $5.00; because some states and jurisdictions do not allow the exclusion or limitation of liability, the above limitation may not apply to you. LEGAL INFO It may be illegal to operate this device in your county. Please consult local authorities before using CYBER MAX LCD! THANK YOU FOR PURCHASING MAXPRO3+! We hope you ll enjoy it as much as we do and remember to tell your friends about it. From all of us we wish you happy broadcasting! PCS Electronics team 18