[TenTec] Omni V & VI MIXER Question

[John]

Hi Jerry,

I've had problems with the Omni VI mixer (and a replacement) getting so hot
in the stock circuit that it became microphonic, necessitating backing off
the RF gain to prevent ringing.  Others have reported this too.  No problem
with the covers off!  ; )

I wouldn't recommend increasing the L.O. power level without installing
louvers or a fan for the lower chassis.

73,

John  W0DC

---- Original Message -----
From: "Dr. Gerald N. Johnson, electrical engineer" <geraldj at isunet.net>
To: <tentec at contesting.com>
Sent: Tuesday, June 24, 2003 8:23 PM
Subject: Re: [TenTec] Omni V & VI MIXER Question


> 23 dBm means 23 dBm LO power. 200 milliwatts. at least the 17 dBm mixer
> only needs 50 milliwatts. That would be the biggest problem with using
> the higher power mixer. The next problem probably is that the RF and
> first IF stage is very close to being the limitation with the 17 dBm
> mixer. Then the crystal filters run into problems handling more than
> that much signal.
>
> It may be that the 17 dBm mixer could handle 20 or 21 dBm local
> oscillator power with improved signal handling characteristics. That's
> often true of lower power MCL mixers.
>
> 73, Jerry, K0CQ
> --
> Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
> Reproduction by permission only.
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