Digital Thermometer to monitor bias

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angelodp
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Digital Thermometer to monitor bias

Post by angelodp »

I started taking my amps temperature. Its interesting to see what actual F temps are on the tubes. is there any protocol for using temperature readings to set bias? Sorry if this is a crazy question.
Stevem
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Re: Digital Thermometer to monitor bias

Post by Stevem »

That's a crazy question so don't let your mind stay there for you long, but in the original tube data sheets there is a max temp number they give.
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roberto
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Re: Digital Thermometer to monitor bias

Post by roberto »

There's no protocol because the bulb temperature depends on:
- initial bias current and B+ voltage;
- loadline;
- signal applied;
- class of the amp;
- temperature of the surrounding air;
- speed of the surrounding air;
- temperature of the surrounding items;
- colour of the surrounding items.

But generally speaking most tubes suggest not to exceed 250 °C as bulb temperature.
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