[Hallicrafters] SR-400A PA cathode resistors

[rbethman]

Thanks Glen!

I don't know what size they are in the SR-400, and can't remember the 
size and value of the SB-102 that I started out with in 1980.

I just recognized the same old pattern!  Under rated components!  This 
is one of those "Institutional Knowledge" things.  A large number of us 
have been there, but now with mail lists, we can so much easier share this!

Bob - N0DGN

Glen Zook wrote:
> There are similar problems with the Collins S-Line and the Heath SB-Line.  The S-Line uses 12 ohm resistors and the Heath SB-Line uses 10 ohm resistors, both 1/2 watt.  I have yet to work on equipment from both series that have not had the cathode resistors change.  The "fix" is to double the wattage.  That is, on that equipment I replace the 1/2 watt resistors with 1 watt resistors.  The "new" resistors are about the same size as the original 1/2 watt versions.
>
> Glen, K9STH
>
> Website:  http://k9sth.com
>
>
> --- On Fri, 8/14/09, rbethman <rbethman at comcast.net> wrote:
>
> While I've never owned or operated an SR-400A, my $0.002 worth, is my gut telling me that you nee3d not only to replace them again, BUT to replace them with a HIGHER wattage version.
>  
> They are apparently dissipating at a higher wattage level than what has been in there.
>  
> It could be a design flaw - OR - the preceeding owner replaced them with a lower dissipation set.
>
>
>       
>
>   

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|             AM Amateur Radio Operator    NØDGN                   |   
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| Bob Bethman                \\\|///     " The absence of a danger |
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