Hej! One simple test is to use a FM broadcast receiver tuned outside the BC
band and place your microphone in front of the loudspeaker. You modulate
your rig with noise and after having switched sideband you can listen to the
unwanted sideband with a transceiver tuned some kHz away from the carrier to
minimize the effect of the flank selectivity in the tx and rx. Prosit de
Hans SM5KI
----------
>Från: measures <measures@vcnet.com>
>Till: "Dave D'Epagnier" <DAVED@ctilidar.com>, "'amps@contesting.com'"
<amps@contesting.com>
>Ämne: Re: [AMPS] 2 tone intermod test
>Datum: tis 23 nov 1999 18.38
>
>
>>
>>Hello, I want to run a 2 tone intermodulation distortion test on my hf
>>transceiver to check for splatter vs. compression level, microphone gain
>>settings etc. I know this is not an amplifier question, but this list is
>>probably where I can get the best answer. I'm running an Icom-756 (and Alpha
>>89A). Running this test on an amp would be pretty straight forward, but how
>>about on a transceiver? Does anyone know how the test is done on
>>transceivers?
>>
>The 2-tone test does not simulate genuine rotten splatter. For this you
>need a complex waveshape. A human or an African gray parrot is such a
>source. The splatter test is done by tuning a double-filter Rx (such as
>a TS-830) about 3.7KHz above and below the test signal to isolate imd
>products from the fundamental) and then comparing the signal strength to
>the fundamental. Since S-meters tend to be inaccurate, a 1db step
>attenuator.should be used to measure relative signal strength.
>>
>cheers, Dave
>
>- BTW -- the only splatter that matters to the FCC is what goes beyond
>the Amateur Radio Service band.
>..
>
>- Rich..., 805.386.3734, www.vcnet.com/measures.
>
>
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>
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