[AMPS] 77DX

[Rich Measures]

>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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