[TenTec] bringing up an old amp

Dr. Gerald N. Johnson geraldj at storm.weather.net
Sat Oct 13 00:16:27 EDT 2007

On Fri, 2007-10-12 at 20:51 -0700, Chuck & Vicki Tifft wrote:
> That is an good procedure, except I would remove the tube(s) first. Many 
> tube types could be damaged from lack of sufficient cooling at reduced line 
> voltages. Many tube types can generate a lot of heat even at  significantly 
> reduced filament voltage.Enough heat to damage seals or warp internal 
> structures. The danger here is that many blowers and or fans do not move 
> much  if any air at reduced line voltages. After the power supply is 
> operating properly the tube(s) can be replaced and the amp brought up 
> normally. Here too I would leave the high voltage off the tube(s) for 30 
> minutes or so to give any gas that may have built up over the years, a 
> chance cook off .
> 73's es GL
> Chuck
> W6RD

Tubs that have not been run in year, need more like 24 hours of filament
or heater alone to warm up the getter deposit and to outgas the heater
and cathode or filament. Two days doesn't hurt.

73, Jerry, K0CQ

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