[AMPS] SB-1000 mods?

[Ian White, G3SEK]

2 wrote:
>
>>
>>Looks like the RCD resistors will do the trick (the 20W parts should fit
>>nicely in the space available inside the L-7 PS). ... ... ....
>>
>Their 5Watter (140 watt-seconds/joules) will do an L-7 with ease since 
>stored energy is c. 80-joules.   If you get a price, please post it. 
>cheers, Mike.
>

The real limitation for this application is power dissipation in normal
operation. For say a 30 ohm resistance, 5W size clearly won't handle
even 0.5A.

Dissipation is downrated drastically with ambient temperature, so the
10W size would be marginal - but possibly OK for an amp that is not
rated for continuous service. If your design philosophy is "key-down
forever" in a big amp, you'd go for 50W. So 20W will be about right for
most people.

In any case, the glitch resistor is one of those components that needs
to be located in a cooling air stream.

Any idea how to get hold of these resistors in small quantities  at
reasonable prices? Now it's Monday, is somebody gonna call RCD?
 
73 from Ian G3SEK          Editor, 'The VHF/UHF DX Book'
                          'In Practice' columnist for RadCom (RSGB)
                           http://www.ifwtech.com/g3sek

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