Marti Electronics SRPT-30, Руководство пользователя

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8/7/2003
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7. Connect an audio voltmeter to the output terminals of the Marti receiver. Feed a 100 microvolt signal into the
receiver from an RF attenuator/sampler connected to the output of the transmitter.
8. Using an audio signal generator connected to MIC INPUT 4 (HIGH LEVEL) of the transmitter with a level 20 dB
below compression level at 2500 Hz, sweep the audio over the audio response range for the transmitter model
number being aligned. Refer to the
SPECIFICATIONS & ORDERING section for correct response for
designator on your transmitter.
9. At the maximum specified response frequency, adjust the FREQ RESPONSE tuning slug in coil L1 on
COMPRESSOR AUDIO board, 800-166 for maximum level or best response curve.
Modulation Adjustment
1. Connect a modulation (or deviation) meter to the output of the SRPT-30/40A.
WARNING
NEVER CONNECT THE MODULATION METER DIRECTLY TO THE RF OUTPUT CONNECTOR OF
THE SRPT-30/40A.
THE MODULATION METER SHOULD BE COUPLED OFF OF AN RF COUPLER OR A WATT
METER.
EXCEEDING THE INPUT POWER RATING OF THE MODULATION METER COULD DO
INTERNAL DAMAGE TO IT.
2. Remove the TRANSMITTER SYNTHESIZER cover.
3. Inject a tone into the transmitter at maximum audio modulation (in most cases this is 7.5 KHz) at 3 dB compression.
4. Adjust pot R63 on the TRANSMITTER SYNTHESIZER while viewing the modulation meter. Turning the pot
clockwise to increase modulation and turn it counter-clockwise to decrease it.
WARNING
INCREASING THE MODULATION WILL INCREASE THE TRANSMITTER BANDWIDTH!
5. Replace the TRANSMITTER SYNTHESIZER cover.
Procedure for Removing Pre-Amp Mixer Board, 800-251
1. Remove knobs and hardware from four level control pots on front panel.
2. Notice the Neutrik mic. Connector has a small hole near the center in addition to the three pin receptacles. This hole
contains a tiny locking mechanism. Using a small (0.75” wide) flat blade screwdriver, insert tool into hole and turn
slowly until screwdriver engages connector lock. Use care!
3. Turn screwdriver counter-clockwise (1/8 turn) until mic. Insert releases.
4. After following the above procedure on each input, gently push the black plastic inserts out of the metal shells while
simultaneously pushing the gain adjust pots inward until the board releases from the front panel.
5. Remove board from the chassis and service. To re-install board reverse the above procedure. Be careful! The
locking mechanism is delicate.