Operating Manual and User Guide FM SERIES BROADCAST FM EXCITERS FM25E FM50E FM250E PTEK

Transcription

1 Operating Manual and User Guide FM SERIES RODST FM EXITERS FME FME FME PTEK

2 Limited Warranty PTEK (SELLER) warrants that products are free from defects in material and workmanship and meet performance specifications provided, however, that: () SELLER liability under this Warranty is limited to repairing or replacing, at its option, any product delivered here under not conforming to this Warranty; () This Warranty is limited to a period of two years; () Minor deviations from specifications which do not affect performance are excluded from this Warranty; and (D) SELLER shall be liable under this Warranty only if: () It is promptly notified in writing by the uyer upon discovery of the failure of any product to conform to this Warranty, () The product is returned to SELLER, transportation charges prepaid by the uyer, () The product is received by SELLER not later than ten days after the last day of the two-year period of this Warranty, and () SELLER examination of the Product discloses to SELLER S reasonable satisfaction that such defects or failures as may exist have not been caused by misuse, neglect, improper installation, repair, alteration, accident or shipping. The uyer will prepay freight to and from SELLER on products serviced here under at SELLER plant; but SELLER may, at its option, elect to perform any repairs here under at the uyer s place of business. The foregoing constitutes SELLER S entire Warranty expressed, implied and/or statutory, except as to title, and states the full extent of SELLER S liability to the uyer or to any other party for any breach of such Warranty and for damages, whether direct, special, incidental or consequential; and, other than as expressly provided in this document. No Warranties, expressed or implied, including any Warranty or merchant ability or of fitness for a particular purpose, are made. No employee, representative or agent of SELLER has any authority, expressed or implied, to alter or to supplement the terms of this Warranty. Warranty Service The Limited Warranty covers parts and labor to the original purchaser for two year. Damage caused by misuse or shipping is excluded from the warranty. efore returning units or material, contact the factory for a Returned Material uthorization (RM) number. Ship all material prepaid. Defective material should be addressed to: PTEK ustomer Service Manager Schooldale Drive San Jose,. 9 () -

3 Safety EFORE PPLYING POWER Verify that the line voltage is V GROUND THE EXITOR. To minimize shock hazard, the excitor chassis must be connected to an electrical ground. the excitor must be connected to the ac power mains through a three-conductor power cable, with the third wire firmly connected to an electrical ground (safety ground) at the power outlet. ny interruption of the protective (grounding) conductor or disconnection of the protective earth terminal will cause a potential shock hazard that could result in personal injury. If the excitor is to be energized by any other source be certain the that chassis is connected to a separate safety ground. Fuses Only fuses with the same required current, voltage rating, and specified type (normal blow, time delay, etc.) should be used. Do not use repaired fuses or short-circuited fuseholders. To do so could cause a shock or fire hazard. DO NOT OPERTE IN N EXPLOSIVE TMOSPHERE Do not operate the power amplifier in the presence of flammable gases or fumes. DO NOT REMOVE THE EXITOR OVER Operating personnel must not remove the exciter cover. omponent replacement and internal adjustments must be made only by qualified service personnel. Output connector The type N output connector carries dangerously high RF voltages which present a shock and burn hazard. NEVER operate this excitor with out the out put connector properly terminated in either an adequately rated load or antenna. Page

4 Specifications MONURL OPERTION udio Input Impedance: ohms, balanced udio Input Level: + dm (.9 volts peak-to-peak) at ohms for 7 khz deviation udio Frequency Response: +/-. d; flat or 7 microsecond pre-emphasis, Hz to khz (other time const. available) Total Harmonic Distortion:.% max.; Hz to khz FM S/N Ratio (FM Noise): 7 d min. below 7 khz deviation at Hz, measured within a Hz to khz bandwidth with 7 microsecond de-emphasis synchronous M S/N Ratio (M Noise): d RMS. below carrier; reference: % M modulation, at Hz with 7 microsecond deemphasis, no FM modulation Synchronous M SIN Ratio (Incidental M Noise): 7 d below carrier; reference: % M modulation, full power at Hz with 7uS deemphasis, FM +/- 7 khz, Hz GENERL Rated Power Output: W, W, W, W Power onsumption: W (for W model) Frequency Range: 7.7 to MHz, in khz steps (other step size to order) Frequency ontrol: Phase locked loop frequency synthesis from high stability master oscillator Frequency Stability: +/-. khz Output Impedance: ohms Output onnector: Type -"N" female VSWR:.: for full power, derate to at inf. Modulation Type: Direct carrier frequency modulation Modulation apability: To khz deviation Multi-Meter Indication: Deviation, Forward Power, Reverse Power, Final I & V Harmonic ttenuation: -7 d, min. ENVIRONMENT ltitude: mbient Temperature -, ft - to + o WIDEND OPERTION Inputs: omposite Unbalanced k Ohms S Unbalanced k Ohms Input Level:. V RMS. (. volts peak-to-peak) for 7 khz deviation Wideband mplitude Response: +/-. d, Hz to khz

5 Front panel layout OUTPUT POWER W (REV X.) DEVITION khz MPS VOLTS PTEK OPERTE OFF FM Series FORWRD POWER FINL VOLTGE REMOTE OFF REVERSE POWER FINL URRENT DRIVE LOW DEVITION. DEVITION FULT DJ POWER FME PTEK 7 Rear panel layout IN FUSE OMPOSITE S MHz MHz khz RF OUTPUT FINL LOWER RISE URRENT VOLTGE REMOTE FWD REV ON OFF PWR PWR GIN GIN GIN MONO IN OHMS FREQUENY Page

6 Key Element Description METER Indicates Forward Power, Reverse Power, Final Voltage, Final urrent and Deviation OPERTE Switch and Indicator This switch sets the FM roadcast mplifier to the Operate Mode; V is applied to the line transformers and this amber indicator is lit. REMOTE OFF Indicator This red LED indicator is lit when the FM roadcast mplifier remote off terminals (rear panel) are open circuit. DRIVE LOW Indicator This red LED indicator is lit when the FM roadcast mplifier can not make the power requested, because for example low drive power. FULT Indicator This red LED indicator is lit when the FM roadcast mplifier is in a fault condition. This can be for one or combination of the following:- Over drive, High supply Voltage, High load VSWR, Over temperature. Meter Select Switch This switch selects one of the following to be presented on the meter ():- Forward Power, Reverse Power, Final Voltage, Final urrent and Deviation. 7 DJ POWER control This control adjust the output power from rated full power to less than %. Ventilation Filter This provides for filtering the environmental air as it is drawn into the cabinet by the internal fan (not used on FME). Key Element Description IN & FUSE V input and Fuse OMPOSITE Unbalanced wide band composite input S Unbalanced wide band input RF OUT TYPE N RF Output FREQUENY SELETION Set switches for frequency selection (only takes effect when unit is switched from off to on) ccessory connector onnections for; Remote off and D indications of Forward Power, Reverse Power, Final Voltage, Final urrent and Deviation. SERIL NUMER Serial number for reference purposes Page 7

7 Installation-Electrical Refer to the Table below for the following description. The installer should assure the ac line voltage is turned OFF before performing this procedure. The electrical connections are installed at the Exciter rear panel. OR (NOT OTH) FROM STEREO ENODER OR STL IN FUSE OMPOSITE S MHz MHz khz RF OUTPUT FINL LOWER RISE URRENT VOLTGE GIN GIN FREQUENY REMOTE FWD REV ON OFF PWR PWR GIN MONO IN OHMS RG TO NTENN/P LNED MONO IN PRT OF USER SUPPLIED REMOTE ONTROL Page

8 Turn-On heckout Refer to the Table below for the following procedure. Stereo pilot level adjustment With Stereo encoder (optional)connected to composite input, adjust composite gain control to give deviation meter reading shown (aprox 7.kHz) Page 9

9 Frequency Selection PLESE NOTE, FREQUENY HNGES SHOULD E MDE WITH THE UNIT TURNED OFF s MHz Switch is (MHz) MHz Switch khz Switch Example Shown.MHz Page

10 Reading the front panel meter FINL VOLTGE FORWRD POWER REVERSE POWER FINL URRENT DEVITION Use the range selection switch (shown Left) to select the meter range POWER Watts DEVITION khz MPS VOLTS(X) PTEK Forward Power The forward power reading is amount of power going to the antenna. The example shown is a reading of Watts. This setting can be changed with the front panel raise lower switch and should be set to the licenced power output (see calculation transmitter power setting ). POWER Watts DEVITION khz MPS VOLTS(X) PTEK POWER Watts DEVITION khz MPS VOLTS(X) PTEK Reverse Power The Reverse power reading is amount of power returning from the antenna. The example shown is a reading of. Watts. correctly matched antenna should not return any power back to the transmitter. The ration of Reverse Power to Forward Power in this example./ would give a return loss of % or -d this would classified as a good antenna. Reverse Powers approaching % will cause the transmitter to reduce the output power (See antenna VSWR Effects) Final Voltage (V) This is the voltage applied to the output amplifier stage. The example shown is a reading of Volts. Used in conjunction with the final current reading will give an alternate method of measuring output power. (Output power = V*I*.7)..7 is the efficiency of the output power amplifier. POWER Watts DEVITION khz MPS VOLTS(X) PTEK Final urrent (I) This is the current consumed by the output amplifier Final stage. The example shown is a reading of mps. Used in conjunction with the final Voltage reading will give an alternate method of measuring output power as described above. This reading will change with output power setting, also antenna match will give different results. ontinued over

11 POWER Watts DEVITION khz MPS VOLTS(X) PTEK Deviation This is the deviation in khz caused by the program audio to the carrier. The meter is peak reading and will vary in accordance with the program (music speech etc.) The peaks should not be more than 7kHz as indicated in this example.

12 Exciter Power Output Vs VSWR Power Watts Power Output FME Power Output FME Power Output FME Power Output FME ntenna VSWR

13 Frequency djustment The transmitter frequency should be checked at lease once every years. If the frequency offset is greater than +/-.khz, adjustments can be made by tuning ; see diagram for location. qualified service technician should make adjustments. lternatively the unit can be returned to the factory for service.

14 ircuit Description General The FME is housed in a U (. ), 9 rack-mounting case. Internally there are P assemblies and cased power supplies. Functional Two V power supplies are connected in series to provide V for the power amplifier and V of the exciter and fan. udio inputs (S omposite and Mono) are connected directly to the exciter board, premphasis is applied to the mono channel only. These input are then summed together and feed to a veractor diode used to tune the VO (voltage controlled oscillator). sample of the VO s output frequency is used by a synthesizer to compare again a reference oscillator. This generates an error voltage which is used to tune additional veractor diodes in the VO to maintain a constant frequency. The main output from the VO is amplified up to W. The output from the exciter board is used to drive the power amplifier to W. Integral to the power amplifier is a harmonic filter used to reduce harmonics generated in the power amplifier to acceptable levels. This output is then feed back to the exciter board and on to the output connecter via a forward and reverse power detector. The exciter board also contains control circuitry, which levels the output power to a level set by a reference voltage. The detected forward power and reverse power are summed and compared to the reference voltage. The gain of the reverse power path is times that of the forward power. This ensures that should the load be remove the forward power will be reduced to a safe level. The reference voltage used by the control circuit is generated by a microprocessor. This value can be changed by using the up/down control on the front panel or by remote contact closure from the rear panel accessory connectors. The microprocessor also feeds the frequency information to the synthesizer. Metering on the from panel is a multimeter, each function is selected by a rotary switch. The voltages for urrent and voltage are provided by the PSU metering board, forward and revere voltages by the synthesizer board. ll these voltages are also connected to the rear panel for remote metering. Mounted on the exciter board is a magnetically latched relay used for remote on/off functions. This requires only a momentary contact closure for either on or off. ycling the power will not change the state of this relay.

15 F ompliance statement THIS DEVIE HS EEN VERIFIED TO OMPLY WITH PRT 7 OF THE F RULES. ccessory connector Pos Function Remote on; Momentary ground to turn the unit on. Remote off; Momentary ground to turn the unit off. Forward Power D indication.v=w Reverse Power D indication.v=.w Final Voltage D indication V=Vsupply/ Final urrent =.V 7 Raise Ground to Raise Output Power Lower Ground to Lower Output Power 9 ohms balanced mono input ohms balanced mono input Efficiency V Output Power FME FME FME Power Output (Watts) Efficiency (%) Power Output (Watts) Efficiency (%) Power Output (Watts) Efficiency (%). %. %. 7%. 9%. %. %. 7%. % 9. % 7. %. % 7. %. %. %. %. %. % 9. %. %. % 9. % Page

16 PTEK SHOOLDLE DRIVE SN JOSE 9 LOK DIGRM SIZE FSM NO DWG NO REV /7/ SLE SHEET OF

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18 G.u R R R R R k L V 7 p 7u FWD PWR.u D N D V IN V Q MRF 7p R D IPRF 7 p T P TRFMR R 7 p Q MRF T L p L 9 7p L 7p L 7p p NOT USED ON EXITERS R7 D N REV PWR.u 7p RF OUT.u R9 R R R.u R 7 PRINTED PRINTED.u.u PRINTED 9 7u.u.u IPRF REV PWR FWD PWR G G J ON RF IN p.u PRINTED G R k Q MRF7 9p 7 9p 9p p p p.u R k NOT USED ON EXITERS Title Schematic P W to MHz Size Document Number Rev <Revode> Date: Monday, March, Sheet of

19 J D R.k R.k R.k R.k V R.7k R k D R7.k V R.7k 7 9 J To Front Pan Metering J V IN R9 R. p + - U LM p.u FWD PWR REV PWR R k 7 9 ON J MTG ON MTG Title urrent & Voltage Metering Size Document Number Rev Date: Monday, January 9, Sheet of

20 M D D METER J SW UP DOWN SW D OUT OF RNGE LO D OUT OF RNGE HI D REMOTE OFF Title P SSY FRONT PN METERING Size Document Number Rev 9 Date: Monday, March, Sheet of

21 D D OMPOSITE IN J N J J S IN RF OUT EXITER to MHz PSU METERING REMOTE ON REMOTE OFF FWR PWR REV PWR FINL VOLTGE FINL URRENT RISE LOWER MONO IN LNED MONO IN LNED V + V IN + V IN - V OUT + V OUT - D V+ V- V- V+ V + V PSU V PSU FRONT PNNEL METERING V - IN Neutral IN LIVE IN Neutral IN LIVE J N J TYPE N RER TERMINL LOK J 7 9 JP JP JP JP J 7 9 FN V D 9 7 J J PLUG MLE ON Title <Title> Size Document Number Rev D <Doc> <Revode> Date: Monday, March, Sheet of