Carl and others - I have never encontered a condition with both rx on same
freq, not to say it could not happen if both were general coverage . But I
think it has to do with mathematical resolution limits in the two
synthesizers . They are "phase locked" in that both start from the same TCXO
but the schemes are different. For instance you can set the sub on VFOB and
use 1 hz steps but the error is something like 5.333 or 5.667 hz so you
still cannot get both RX on same freq. You can go into the RS232 commands
but those are also limited to 1 hz steps.
I have toyed with building an external LO for either the main or the the sub
RX so they could at least be on the same freq but would not be truly phase
locked - I suspect you could get them close enough for many uses.
There is another factor that is not too important in many applications but
are in some applications and that is that the delay through the main is
substantially different than the delay through the sub rx. Put an external
keyed signal into the input - both rx on same antenna input and look at
recovered audio on a two channel scope .
Carl - can you get deep enough into the guts to do sub hz steps ????
I agree about what was said about true diversity - I begin to sense the
improvement even using the sub on 1 hz steps and getting close. I really
wish TT would quit saying the O is capable of "diversity" reception - but
guess its how you define "diversity". Everything I have heard about the K3
says they truly have it - and I assume the two delays are the same , dunno.
73 Hank K7HP
>> My N4PY Orion software has can be operated in diversity mode. And my
>> program has an adjustment in it to allow for a slight frequency offset in
>> the 2 receivers and correct it.
>>
>>
> That sounds interesting. Can you explain how it works? I thought the
> reason the two receivers are always off frequency by some small amount
> is that they use different PLL schemes, with different minimum
> resolution step sizes. How can software change that? Perhaps I've got it
> all wrong.
>
> Even with different step sizes, at some frequencies the two receivers
> might be on exactly the same frequency. Maybe the N4PY software can be
> operated so that only these particular frequencies can be tuned?
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