[Amps] Is after-powerdown cooling desirable?

[rbethman]

I run an Amp Supply LK-500ZB.

While it isn't a problem, being a VERY well built and designed 
amplifier, I have used nylon screws and nuts to place a muffin fan over 
the top of the 3-500Zs.  I have it manually switched.  I turn it on just 
before turning the amplifier off.

I have found that it reduces any residual heat fairly quickly.

If history is any indicator, I'm STILL running the same Eimac 3-500Zs 
that I got with it in 1999.

I have full output power, AND I *DO* feed it AM with a DX-60.  I tend to 
"ragchew".  So this amp has been heavily used on both AM and CW.  Some SSB.

YMMV

Bob - N0DGN

On 12/18/2011 11:55 AM, Jim Garland wrote:
> <SNIP>

> The situation with glass tubes is different, since the internal anodes 
> typically show color and run at a temperature much higher than the 
> glass envelope. Thus, the heat will continue to radiate through the 
> glass envelope for awhile after turnoff, and an airflow will keep the 
> glass and seals cool during this time. 

> 73, Jim W8ZR