Low heater voltage 124 classic (FIXED)

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 4:11 pm

Fired up new build...
heater voltages really low...2.1V
MC Twin iron ....using 2 100 ohm for CT

Darin

sonicmojo · Post by **sonicmojo** » Mon Nov 28, 2011 4:34 pm

Darin,

Don't be offended but I'll start with the obvious. You don't have it hooked to a current limiter, do you? This has bit me before, especially at the end of a long day.

fishy · Post by **fishy** » Mon Nov 28, 2011 5:03 pm

Is that with or without tubes?

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 5:33 pm

Don't be offended but I'll start with the obvious. You don't have it hooked to a current limiter, do you? This has bit me before, especially at the end of a long day.

sonicmojo...no offense taken...I was in a hurry this morning, but no limiter...
voltage caught me off guard.

fishy...without tubes

Darin

Structo · Post by **Structo** » Mon Nov 28, 2011 5:46 pm

How are you measuring the heater voltage?

ToneMerc · Post by **ToneMerc** » Mon Nov 28, 2011 5:48 pm

Unsolder the PT filament leads and check for 6.3V straight from the PT.

TM

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 5:49 pm

Structo wrote:How are you measuring the heater voltage?

Hi Tom
using AC setting and going across pins 4-5 to pin 9?

Darin

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 5:53 pm

ToneMerc wrote:Unsolder the PT filament leads and check for 6.3V straight from the PT.

TM

Will do TM...didn't think of that thanks

Darin

ToneMerc · Post by **ToneMerc** » Mon Nov 28, 2011 6:50 pm

It almost sounds like your sockets are wired to one half of the tap, you do have a resistor across pin 2 and 7 right?

TM

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 7:08 pm

ToneMerc wrote:It almost sounds like your sockets are wired to one half of the tap, you do have a resistor across pin 2 and 7 right?

TM

TM
voltage reads 2.2V with unsoldered leads?

I have a 100 ohm from pin 2 to ground also one from pin 7 to ground

ToneMerc · Post by **ToneMerc** » Mon Nov 28, 2011 7:23 pm

So that's straight off the two greens because it has no center (grn/yel) tap correct? I would say that your PT is the culprit then.

TM

dcribbs1412 · Post by **dcribbs1412** » Mon Nov 28, 2011 8:11 pm

ToneMerc wrote:So that's straight off the two greens because it has no center (grn/yel) tap correct? I would say that your PT is the culprit then.

TM

Yes off the 2 green's no CT....
Not sure what I did...but this is the 1st iron I've had bad
total bummer...

Darin

heisthl · Post by **heisthl** » Tue Nov 29, 2011 6:57 am

Just out of curiosity, what about the unloaded main primary voltages?

dcribbs1412 · Post by **dcribbs1412** » Tue Nov 29, 2011 2:23 pm

heisthl wrote:Just out of curiosity, what about the unloaded main primary voltages?

Assuming I'm measuring right...411V
...do I have a DOA PT?

Darin

10thTx · Post by **10thTx** » Tue Nov 29, 2011 3:54 pm

The voltmeter has a new & good battery in it correct?

I only mention that because of getting "off" readings on an amp with a voltmeter (thinking it was the PT) only find the battery was bad. I've seen others on amp forums post doing the same mistake.

Just trying to rule that concern out.

With respect, 10thtx

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Low heater voltage 124 classic (FIXED)

Low heater voltage 124 classic (FIXED)

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Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)

Re: Low heater voltage 124 classic (FIXED)