[AMPS] AL-80B Amps

[Tom Rauch]

> I think that what he is saying is that he is shocked to see that on
> stand-by only the keying relay is disabled and the HT is NOT switched off.
> I would think that in stand-by a good amp should be just loafing with the
> HT removed (or at least reduced), etc.
> 
> 73,  Carl  VE9OV

OK, I didn't really follow his line of thinking.

It came off as "what a silly mistake" and my reaction is thinking a 
standby switch makes the PA safe sure is!

 What he was basing his statement on was the fact that military 
equipment disable HV when on standby.

Even considering that, I can't imagine why anyone would depend 
on a standby switch to make an amplifier safe!  

But here are the two main reasons that isn't done:

1.) The AL80B, as with many other amplifiers, shares a common 
filament and plate transformer. There is no way to remove HV with 
the standby switch.

2.) Hams frequently turn the standby switch off and on while still 
operating, to reduce power or bypass the amplifier. Commercial 
stations generally do not place PA's in-line and out-of-line while 
using the station.

Common sense dictates NEVER removing the cover and 
connecting the PA to the mains. 

Common sense dictates NEVER working on any PA where you 
depend on a front panel switch for your personal safety.

Sometimes we get sloppy and need to be reminded of that!


73, Tom W8JI
w8ji@contesting.com

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