His "explanation," if I read it correctly, seems to be a tad "at odds" with
what Sherwood Engineering's measurements show....or am I missing it????
> From: w8ji@w8ji.com
> To: rodenkirch_llc@msn.com; topband@contesting.com
> Date: Tue, 6 Oct 2015 18:29:09 -0400
> Subject: Re: Topband: SDR Mythbusters - ADC Overload myths debunked...
>
>
> From Stu, K6TU
>
> As with any technological change, there are many myths, past truths or part
> truths that get repeated endlessly and out of context by those frightened or
> challenged by the change.
>
> Software defined radios are no exception to this in the world of Ham Radio.
>
> Steve Hicks, N5AC and the VP of Engineering at FlexRadio has posted an
> excellent explanation and bust of the ADC overload myth on the FlexRadio
> community. You don’t need to be registered on the community to read this
> excellent write up:>>>>>>
>
> Regardless of the fact they cannot possibly overload, they overload here.
>
> I don't understand his explanation at all.
>
> We had ONE transmitter on while trying to receive. The ADC could not handle
> the level of one transmitter. Because there was no in-band front end
> selectivity, the spacing did not matter. We could not get the strong local
> signal outside a roofing filter.
>
> With two transmitters on different non-synchronized frequencies, there will
> be periods of time when the voltages add. There will be periods when the
> voltages subtract. Anything following the summing point has to handle the
> random peaks, even an ADC.
>
> The Flex we tried here, using it to listen while ONE transmitter was
> running, just went nuts. It was equally bad no matter what the spacing. At
> least with a radio with roofing filter, we could move the radio up or down
> band and use it.
>
> 73 Tom
>
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