>Subject: Re: [AMPS] 77DX
>Sent: 3/29/1997 2:46 PM
>Received: 3/29/1997 4:57 PM
>From: Lee Roger Wical, leewical@lava.net
>To: Rich Measures, measures@vc.net
>CC: LEEWICAL@LAVA.NET
>
>Richard, AG6K:
> Don't know if I asked you this question or not. Cannot find any
>reference to same.
> Do you vendor a replacement plate choke for the 77DX
not any more. I never had much call for the smaller chokes.
>......so I can use
>the rig on the 24MHz ...........
The stock choke will work provided you remove some turns. Check it with
a dipper before you give it the smoke test. Resonances should be parked
at least 5% off the main road.
>PS Same question in using the SB-220 on 12Mtrs/24MHz?
There are no hv-rfc resonances below 35Mhz, so no mod is needed.
Free unsolicited advice for the 77: The tank is designed to match 2000
ohms. When a second tube is installed, the tube output Z drops to 1000
ohms. The 77's tri-state bias scheme is nutsville. If you want the 77
to sound smooth on the air, a bi-state bias circuit is needed.
R. L. Measures,ag6k,805-386-3734
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