[Moon-net] Triode grid current

[WA4EWV]

Hello All:
I have been told that I should put an SWR bridge from the output of the 
transmitter to the input of the 8877. This makes input tuning a little 
easier.
Al
WA4EWV

----- Original Message ----- 
From: "LANCE COLLISTER" <w7gj at q.com>
To: <n0ipl at psouth.net>
Cc: <moon-net at list-serv.davidv.net>
Sent: Saturday, March 08, 2008 9:27 AM
Subject: Re: [Moon-net] Triode grid current


>
> Wilt Barnum wrote:
>> Hello all, I have a pair of 3cx800s back in service after a long time. I 
>> cannot seem to find the point of minimum grid current and max output. Can 
>> anyone suggest a tuning proceedure? and the relationship of anode loading 
>> to proper tuning?
>>
>> Thanks, Wilt W1IPL
>> _______________________________________________
>> Moon-Net posting and subscription instructions are at 
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>>
> Hi Wilt,
>
> I have never operated the 3CX800A7 tubes, but I know with my 8877 
> amplifiers, I have
> always tuned up the tube as W6PO instructed me years ago.  That was to 
> peak the
> output while adjusting the input tuning as well as the plate tuning and 
> loading.
> Then, as you get closer to maximum power ratings, you can tweak the plate 
> loading
> control slightly to reduce the grid current with very little change in 
> output power.
>  Then re-peak the tuning controls for maximum output at that loading 
> setting.  This
> technique has worked very well for me in finding the optimum safe 
> performance
> settings for the tube.  GL and VY 73, Lance
>
> -- 
> Lance Collister, W7GJ (ex: WN3GPL, WA3GPL, WA1JXN, WA1JXN/C6A, ZF2OC/ZF8)
> P.O. Box 73
> Frenchtown, MT  59834  USA
> QTH: DN27UB
> TEL: (406) 626-5728
> URL: http://www.bigskyspaces.com/w7gj
> 2m DXCC #11/6m DXCC #815
>
> _______________________________________________
> Moon-Net posting and subscription instructions are at 
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>
>
>