What would cause heater voltage to rise?

[dehughes]

Hello there,

So, the amp I made is shaping up nicely, again, thanks in great part to your help. Thanks.

I remember measuring and cataloging the voltages once I had the amp up and running for the first time, and looking back I read that each side of my heater wires was putting out 3.14 volts. That seems right....as together that would be 6.28 volts....seems normal, yes?

However, I measured the heater wires again just today and noticed that each side is measuring out at 3.35 volts, which puts the total at 6.7-ish... Is this something to be concerned with? What would cause the voltage to rise? The amp was basically brand new when I measured things (new trannies, caps, resistors, tubes, etc...), so maybe that's part of it?

Lemme know if this is something to look into, or still within normal parameters...

THANKS!

[Zippy]

Did you measure your source voltage both times? How does that compare? Are these the only voltages to change?

[dehughes]

Did you measure your source voltage both times? How does that compare? Are these the only voltages to change?

I didn't measure the wall voltage the first time....the other voltages seem to be pretty close to normal....maybe one or two volts difference. The tubes have been changed since that first measurement, so maybe that's it?

[MarkB]

That's fine. Plus or minus 10% is the general rule. I wouldn't be concerned until it got to 6.9V or higher.

[dehughes]

That's fine. Plus or minus 10% is the general rule. I wouldn't be concerned until it got to 6.9V or higher.

Sweet. Thanks. People on other boards seem to think line voltage is the suspect....could be...maybe I had the air conditioning on when I measured the first time...who knows...

[drz400]

That's fine. Plus or minus 10% is the general rule. I wouldn't be concerned until it got to 6.9V or higher.

Sweet. Thanks. People on other boards seem to think line voltage is the suspect....could be...maybe I had the air conditioning on when I measured the first time...who knows...

Many times your heater tap is rated to produce 6.3 at x amps
IF you are not pulling those amps it might run higher

[dehughes]

That's fine. Plus or minus 10% is the general rule. I wouldn't be concerned until it got to 6.9V or higher.

Sweet. Thanks. People on other boards seem to think line voltage is the suspect....could be...maybe I had the air conditioning on when I measured the first time...who knows...

Many times your heater tap is rated to produce 6.3 at x amps
IF you are not pulling those amps it might run higher

Very good point...thanks.