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MK3TXTesting

MK-III transmitter testing

Power up first tests

LED

Voltages

Signals

Equipment needed: multimeter, spectrum analyzer with 10 dB attenuator, or USB precision power meter; N to SMA and SMA to MCX cables, length 1 m; 100W 30 dB power attenuator + 20 dB safety attenuator

1. run radcelf_ini_cal.sh to set the RADCELF to calibration mode (no chirp, 80 Hz off)

2. proceed with calibration of CRX-8 LO-DISTRIB TX signal

3. install 100W 30 dB power attenuator on output of power amplifier

4. connect spectrum analyzer with 20+10 dB safety attenuator after the power attenuator

5. power up amplifier

6. connect the CRX-8 LO-DISTRIB TX signal to the input of the amplifier

7. adjust TX output level using blue potentiometer POT1 on LO-DISTRIB board again to match TOMCO BTM-250SA rated power of 50W or +47 dBm (or -13 dBm after the safety attenuators)

 TX output: 47 dBm @ 27 MHz

8. check harmonic levels of 2*f0 and 3*f0, must be less than f0 - 60 dB