[sdiy] heater voltage: how much is too much?

[Bob Weigel]

They tend to run that way being a power tube I'm sure.  You used all new 
parts so can't have a leaky bypass cap or anything.  So you should be ok 
with that I guess.  Measure volts across the 180 ohm resistor and 
calculate the current and make sure it's within spec of course. -Bob

anthony wrote:

> The only thing that made me wonder is the fact that the 50L6 is VERY 
> hot to the touch - compared to the 12SQ7. I mean the plates aren't 
> glowing or anything. I don't think I have it biased too hot. I used a 
> 180 Ohm cathode resistor. If anything I figure it has soem room to 
> bias it a little hotter. Especially considering how soft the amp is 
> without added gain.
>
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>
>> No it'll be fine.  Heaters usually have a lot of overvoltage tolerence.
>
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>> anthony wrote:
>>
>>> For the heaters in my 50L6 amp I used a 50C5 in series with the 
>>> 50L6GT and the 12SQ7GT to get a more proper heater voltage of around 
>>> 112 VAC. However my wall voltage is 120 VAC. I was wondering if this 
>>> difference would be too much. My first thought was that it shouldn't be
>>
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