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ReceiverTest

RECEIVER TEST

For testing your receivers, turn on the radar, just the 6 Amp break. Connect directly the ddsB output (+5.5 dBm) to the receiver using 60 dB attenuation (-54.5 dBm). The d-tacq has to be in calibration mode with 80 Hz off.

Connect the output I / Q to oscilloscope. Change coupling to AC, termination to 1M Omhs and Bandwidth to 20 MHz.

You should see your I/Q signal on oscilloscope.

The amplitude of the signal has to change if you aren't using a jumper in attenuation pins of LF and HF, move your jumper to prove it.

LF and HF attenuation are computed to be -10 dB. If you aren't able to see the two signals you can check that there isn't a burned trace.

Check the output of Lo-I and LO-Q. The central ping is ground and the other ones are signal.

Check on the oscilloscope that you have a signal and the frequency must be the frequency of DDS.

Check the output of SPEC-I and SPEC-Q. The middle pins are signal and the side pins are ground.

SPEC-I and SPEC-Q let you look at the signal from the "antenna" after the splitting by the T in the traces. The signal should be identical.

Check the output of MIX-I and MIX-Q. The middle pin is signal and the side pins are ground.

MIX-I and MIX-Q let you look at the signal after the democulator (the off-white little bix). They should be 90deg from each other.

Use a scope probe (or two), clip ground to any ground, and check the test point for signal. You should detect I and Q there.

Some LEDs don't light up for a power supply failure or an LED failure. Check continuity using a multimeter, connect one probe to any ground and the other probe to the led. If the LED lights up there is a power supply failure.