QRM Eliminator X-Phase Canceller | SDR Noise Eliminator | QRM Eliminator for SDR Receiver

Tired of local QRM on HF? Just try the QRM elemintor and it will help to reduce the local noises from your home appliances, like computers, television, power supplies or else. You do not need to know where the noise comes from, just connect it to your radio, connect 2 antennas to MAIN and AUX port, it will phase out the local noises.

The QRM canceller is inserted into the feeder of the antenna from the trx without any other modifications to the radio. The box has a built-in PTT control to keep the canceller connected during transmission. However, an additional auxiliary receiving antenna is required, such as a 144MHz Band antenna or only a few meters of wires in a shed. The two antennas receive unwanted signals, resulting in different phases. The QRM canceller now allows adjustment of the phase angle and amplification to cancel the unwanted signal before it reaches the receiver front end! It is based on a completely innovative concept and cannot be compared with the normal “silencer” performance.

Connections:

•  Transmit Antenna to “MAIN”
•  Transceiver to “TRX”
•  Auxiliary Antenna to “AUX”

How To:

Turn on the unit, adjust GAIN1 to have the noise signal with same level on both antennas, then adjust with the PHASE and GAIN2 knobs the noise, both alternatively, to a minimum of noise. Then adjust the GAIN1 knob for less noise. If not possible, readjust the PHASE and GAIN2 knobs again until the minimum can be found. A bit difficult at first try, don’t give up to early!
When found a minimum the local noise has to be nearly or totally gone and the wanted signal will be left over. If this signal is gone as well => the aux. antenna picks up to much of the wanted signal AND of the noise, change /modify the antenna. As all 3 knobs interact with each other, the adjustment can be a bit tricky.

When you believe, the unit does not work…. use your antenna analyzer as signal generator, put it somewhere in the shack. Connect both antenna jacks with a little banana lead and check for a S9 signal from your analyzer. Then with GAIN fully counterclock-wise, the signal must be phased out after adjusting the PHASE and GAIN2 knobs.

Package Includes (not for Kit Version):

1. QRM Eliminator × 1
2. PTT Cable ×1
3. DC2.1 Cable x 1
4. Telescopic Antenna with SMA port x 1