>My discussions with George (W2VJN) at InRad suggest that an Omni VI+ with
the new (soon to be out) InRad roofing filter may be a worthy competitor
when it comes to IMD dynamic range (even stock it's not too shabby). George
indicated that "the improvement for close in signals is quite dramatic and
places the Omni VI into the group of today's top performing radios."
Very true and I know of at least one person who has been using a
homebrew version of this in an Omni VI for about a year. The modified
Omni has a similar front-end design to Orion and performance should be
very similar to the Orion with the #762 filter.
>The filter will be available in a 600 Hz and 2400 Hz version. The first
batch, to those of us who got on the pre-production order, should be shipped
late next week. Hopefully a modified rig will soon make it to Sherwood for
some independent tests.
Are you sure about that 600 Hz version? George's white paper below
says it is a 400 Hz version, which is one reason I feel it could do slightly
better than Orion with Inrad's 600 Hz #762.
http://www.qth.com/inrad/roofing-filters.pdf (page 6)
"Ten Tec Omni VI series: We are presently working on a roofing filter mod for
the Omni VI+ radios. Plans are not quite formalized yet, but some preliminary
data from our lab is shown below.
Signal Spacing IMD DR Filter Bandwidth
20 kHz 100 dB 2800 Hz
5 kHz 93 dB 2800 Hz
20 kHz 100 dB 400 Hz
5 kHz 100 dB 400 Hz
1 kHz 90 dB 400 Hz
We hope to make this unit available in the late fall or winter of this year."
In any event, I suspect two Ten-Tec rigs will be at the top of
Sherwood's list for a long time to come, and it will just be interesting
to see which is #1 and which is #2...they both should be very close.
73, Bill W4ZV
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