[R-390] R-390 vs R-392?

[Barry]

Amen to that!  I read it and, to me, it is well-written and understandable.  Thanks Mike!

Barry - N4BUQ

> Wow! Ask a question, get an exquisite dissertation! I noticed the range
> problems with the AGC and strong signal behavior, but missed a lot of
> the subtlety. I didn't bother to spend any time on the audio and AF
> side after  declaring it a train wreck. thanks for digging into it so
> thoroughly.
> 
> Thanks for your most complete and informative study.
> May I post your missive on my web site? (with attribution)
> 
> --A
> 
> On 3/3/2026 17:43, Mike Peace wrote:
>> Hi Andy,
>>
>> Here's the technical analysis comparison between the R390 and R392,
>> see link:
>>
>> https://vk6ada.com.au/wp-content/uploads/2026/03/R390_vs_R392_Technical_Analysis.pdf
>>
>> Mike
>> VK6ADA
>>
>> On Tue, Mar 3, 2026 at 4:16 PM James A. (Andy) Moorer
>> <jamminpower at earthlink.net> wrote:
>>
>>     Has anybody done a comparison between the R-390 and R-392
>>     performance? I
>>     know the 392 is de-featured (one audio output, fewer BW choices), but
>>     has anyone just compared apples to apples? That is, set the 390
>>     and the
>>     392 to the same station, using the same antenna, same settings? I
>>     have
>>     gone over the schematics pretty carefully and I don't see any
>>     difference
>>     in the core signal handling. The 26A6 tubes have perfectly reasonable
>>     behavior and have equivalent bias, screen grid, noise figure, and
>>     so on.
>>     So, do they sound any different?
>>
>>     I noticed two other things - the IF output for the 392 is a wreck.
>>     Seems
>>     to be half-wave rectified. Lot of nonlinearity there. And the audio
>>     output stage is quite different from the 390. That all-important IF
>>     stage appears to be identical to the 390.
>>
>>     So - what's the story?
>>
>>     -A
>>
>>     --
>>     James A. (Andy) Moorer
>>     www.jamminpower.org <http://www.jamminpower.org>
>>
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> 
> --
> James A. (Andy) Moorer
> www.jamminpower.org
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