Adding a 3rd tube is an interesting issue.
First I am speaking in general terms. I am not familiar with the 76.
I have pondered this as a paper exercise and came away thinking there
is a lot more to it than just adding a socket and connections for a
third tube with the chassis space. It seems to me that in general an
additional tube:
changes the anode Z so the output network may need a redesign or adjustment
may cause stress to the bandswitch, inductors and load caps
may draw too much current on the plate choke
Assuming cooling and h.v. supply are not issues, you have to work out
the new filament supply and maybe a change in the input Z
If the plate blocking caps were barely okay before they may have to be
replaced.
Anyway I found it an interesting thing to contemplate.
73
Rob
K5UJ
On Mon, Jan 30, 2012 at 9:16 AM, Charles Hedrick <cchedrick@gmail.com> wrote:
> Good morning all,
> I have and would like to add a third 8874 to my Alpha 76 but need a socket
> and plate cap. If anyone has these to part with, please let me know.
> Thanks,
> Cam
> WA4JKW
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