[Boatanchors] LINE VOLTAGE, FILAMENT VOLTAGE and SANITY

[Richard Knoppow]

----- Original Message ----- 
From: "W2HX" <w2hx at w2hx.com>
To: "Gary Peterson" <kzerocx at rap.midco.net>; 
<boatanchors at mailman.qth.net>
Sent: Tuesday, January 06, 2015 6:32 PM
Subject: Re: [Boatanchors] LINE VOLTAGE, FILAMENT VOLTAGE 
and SANITY


>> Do not attempt this procedure with indirectly heated 
>> cathodes, such as the venerable 4CX250B.
>
> For us noobies, could you explain why this procedure is 
> inadvisable with indirectly heated cathodes?
>
> 73 Eugene W2HX
>
    I remember reading the same thing but can't remember 
where or what the reason was. Its common to reduce filament 
voltage on diodes used as detectors or especially in noise 
limiters because it reduces the effect of contact potential. 
I have also seen this spplied to amplfiers. Again, my memory 
is not coming up with complete information but I think in 
power amplfiers the filament can be damaged.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com