[AMRadio] N3RHT Shack Update

Larry Szendrei ne1s at neandertech.com
Sat Mar 5 14:55:58 EST 2005

Merz Donald S wrote:

>The 2 supplies run two 3B28 rectifiers each. 3 of them run with no visible indication at all. 
>You can't even see the filament. But one gets a dramatic glow under load. 
>I have not seen this before--is that gas in the tube?
I hope so - 3B28s are supposed to have gas in them (some noble gas or a 
mixture of them; not sure but I seem to recall argon). But seriously, 
the fact that one is glowing more than the other might indicate a 
problem with one of the tubes, not necessarily the one that glows more, 
or a difference in the amount of current being handled between the two 
tubes, which needs to be dealt with.

> So with any luck I should have the rig on the air sometime in April. This will be the 
>highest power AM TX in my shack when it's done. 
Can't wait to hear it (and I'm sure I will, if you're reasonably active 
with it) and perhaps engage it/you in a QSO.

I'm slowly but surely working my way down the project list to the 
restoration/completion of a homebrew 30's AM open relay rack 
transmitter. Except this one will use 866As in the PS for that "trippy 
blue glow."


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