Yep... here it is right here, wayyyy back on v5.33:
/** DIVERSITY WORKS WITH MISMATCHED MAIN/SUB RX FILTERS: Diversity mode
in the K3S (or a K3 with the KSYN3A installed) now works with any
combination of main/sub RX crystal filters. They can have different
bandwidths or offsets, and it's not necessary to have an equal number of
filters in each receiver. Note: Matched filters are optimal for
diversity, but non-matched filters will still perform well.*//*
*/
"Matched filters are optimal...."
End of discussion as to IF I will get matched filters.... Now to decide
between the "in-house" 6-pole I just bought, or an INRAD #701 that
matches the one I bought with my MAIN Receiver...
73,
______________________
Clay Autery, KY5G
(318) 518-1389
On 01/14/20 11:16, Nr4c wrote:
I think you’ll find in the release notes that main/sub filters no longer need
to be matched.
However, I think I’d be happier with two alike, either 2 8-poles or 2 6-poles.
Sent from my iPhone
...nr4c. bill
On Jan 14, 2020, at 7:18 AM, Clay Autery <[email protected]> wrote:
The 400Hz filter on my Main RX is an Elecraft (by INRAD) 8-pole filter in a
Faraday cage and no offset.
The 400Hz filter I just received for my SubRX is an Elecraft (by Vibroplex?)
that is a 6-pole filter with no Farady cage AND it has a -0.71 kHz offset.
I called support when I saw the obvious differences, and they said, "Don't worry
about it. Enter the SubRX offset exactly as on the crystal (no averaging with the
[supposed] 0.00 offset on the 8-pole filter), and let the new Synthesizers do the heavy
lifting." or words to that effect.
I hear what was said, and I don't want to come off like I don't trust what I was told....
But something simply is not sitting right with me on this.... a 6-pole
"matched" with an 8-pole? No offset averaging? What about the difference in
the skirts between a 6-pole and an 8-pole.... Aren't the cutoffs and cutoff rates
different? I realize that things change, and that perhaps the instructions for averaging
the offsets is not applicable here... (though I don't yet understand why)
Can someone clear this up for me so even I can understand it.
Seems to me that I either need to get a matching INRAD-made 8-pole, or buy
another of these new parts and try to get it matched.
Want to move on this, because IF I am going to have a hope in getting a
"matching" 6-pole (new stock) 400 Hz filter, I need to try and do so from
within the same batch that the one I just bought came from.
The prospect of finding an "by INRAD" 8-pole available on the market seems much
less likely...
Obviously, I am operating on a number of assumptions here... which is why I am
asking...
73
______________________
Clay Autery, KY5G
(318) 518-1389
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