Yes, another good point guys. Prior to the mods, my Omni Six's CW note
sounded much different when switching between sidebands on an external
receiver, using a wide I.F. filter setting. The same is true when listening
to W1AW's 20-meter Omni Six Plus CW signal. If they would send me their
rig, I'd make the necessary changes gratis!
Here's an alternative to the 2.8 kHz filter that may appeal to some:
Use a small reed relay to bypass the 2.4 kHz filter ONLY in the CW mode.
(keep the contact leads short!) A hard bypass with the relay's dry contact
closure is fine for this purpose and impedance matching is not critical.
For several months, I've been using a #18 AWG buss-bar jumper instead of the
relay and it works just fine. Nevertheless, the new INRAD 2.8 kHz filter
offers a higher fidelity receive bandwidth that I personally like and
LSB/USB symmetry is excellent. However as Clark pointed out, the added
receiver fidelity improvement will be much more apparent when INRAD produces
the new 2.8 kHz @ 6.3 MHz I.F. filter for the second I.F. stage.
-Paul, W9AC
-----Original Message-----
From: Steve Ellington <n4lq@iglou.com>
To: w8au@sssnet.com <w8au@sssnet.com>
Cc: tentec@contesting.com <tentec@contesting.com>
To: <tentec@contesting.com>
Date: Wednesday, January 06, 1999 7:23 PM
Subject: Re: [TenTec] Omni VI chirp comment
>
>Yoop/bloop eh? I see your point but the Omni VI's chirp seems to have a
>different sound. I've heard them sound perfectly clean (except for the
usual
>hard keying) then upon switching sidebands I hear the leading edge twirp. I
>think it's got something to do with Paul's filter theory.
>
>Yes, W1AW is a discrace on 20 meters. I'm listening to them right now and
>they sound like trash. I wonder if they just don't care? I remember reading
>in QST how TT donated the rig and how it had to be modified for greater
>frequency stability. Maybe they just don't want to look a gift horse in the
>mouth.
>
>N4LQ
>
>
>>
>>Right, Steve..... the old tried, true method (listen with a critical ear)
>>is to switch sidebands....if you hear a "yoop" on one sideband you will
>>hear a "bloop" on the other. This is a dead givaway. For "microchirp"
you
>>have to listen close to the leading edge.....
>>
>>Appreciate all your discussion (with Paul) as it has shed a lot of light
on
>>a problem I've been aware of in recent years. That's why I have avoided
>>picking up a VI. I had assumed it was due to PLL instability, but that's
>>as far as I got without having one to play with.
>>
>>And, yes, the W1AW signal is an embarrassment, isn't it?
>>
>>73,
>>Perry
>>>
>>>>
>>>> I've been following this thread for a while and did not understand what
>the
>>>> ruckus was all about.
>>>> I finally tuned into W1AW....and I must say that the CW sig is not the
>>best
>>
>>
>>
>>--
>>FAQ on WWW: http://www.contesting.com/tentecfaq.htm
>>Submissions: tentec@contesting.com
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>>
>>
>
>
>--
>FAQ on WWW: http://www.contesting.com/tentecfaq.htm
>Submissions: tentec@contesting.com
>Administrative requests: tentec-REQUEST@contesting.com
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>Search: http://www.contesting.com/km9p/search.htm
>
>
--
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
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