HI Stephen,
Anything other than both the SDR and the BitX connected by an appropriate attenuator or a directional coupler will yield frequency dependent results, and not real numbers.
The correct method would be an accurate and frequency suitable wattmeter, a calibrated RF Probe and voltmeter, a scope that has the proper frequency range and a known accurate termination.
Nothing like having some good test equipment if? you are? homebrewing, testing, aligning etc.
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During these tests, the uBITX was on a desk within 36 inches of the SDR dongle which was lying on the floor. Could I connect a 50 ohm dummy load to the antenna connector of the SDR to achieve sufficient attenuation? I don¡¯t have a direct coupler or real attenuator.
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99% of the 9:1 and 4:1 Baluns are not baluns at all- they are simply transformers, still allowing the outside shield of the coax to be part of the antenna. And as above, the antenna¡¯s response is frequency dependent and just as bad, the output power of the Bitx is likely all over the map as it is seeing widely ranging SWR.
Secondly, with the 2 rigs that close to one another, direct radiation pick up may be the coupling mechanism, or a good part of it.
Just not a good situation.
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Dale W4OP
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