TrainWreck Express voltages

[sliberty]

Are the voltages in the Kelly schematic in the files section fairly typical?

[MooreCowbelle]

My build came in very close to those on the schematic.

[sliberty]

My voltages are low.

B+1=369
B+2=328
B+3=263
B+4=248
B+5=235

as compared to the schematic

B+1=395
B+2=380
B+3=298
B+4=282
B+5=267

Should I be worried? Is there anything I should be checking?

[Normster]

Is your wall voltage 117? Since the PT ratio stays the same, a 5 volt drop in wall voltage will drop HT by about 15-20 volts. During the heat wave we're having in CA, I've seen my wall voltage go as low as 110 volts, enough to throw off my HT voltage by 25 volts.

[sliberty]

Well, I just measured again, and my A/C was 118V, and my various B+ measurements were a little higher than before - a little closer to the schematic, although still somewhat lower. I'll have to check it again tomorrow.

Thanks for the tip.

Steve

[gearhead]

I haven't fired up an amp build yet (getting close) and was wondering what do you use to measure the voltage? I assume it'd fry my hand-helda multimeter?

[sliberty]

Thats what I am using. In fact, its the only piece of measurement equipment I own

[Allynmey]

Gearhead, What kind of DMM do you have?

Allynmey

[gearhead]

Working or non-working? LOL. I seem to pop fuses like popcorn.

My main one is a Triplett, but both fuses are toast now and can't seem to find replacements other than the Triplett site. So by default, am using a Radio Shack (top of the line at the time). The one which can test transistors (for stompboxes). Believe it does have a 10A tap.

[sliberty]

I also have a Radio Shack that "was" top of the line when I bought it. I am not sure if its fried or what though. I can get most readings from it, but when I try to read the voltage on the plates of the EL34's, the meter just gets unstable and never provides a reading. Also, when I try to read the voltage across the 1ohm bias probe resistors, I get numbers that don't make sense - like .003 VDC.

I need to buy a good meter.....

[MooreCowbelle]

This is the one I have - works just fine!

http://www.radioshack.com/product/index ... Id=2104750

The only problem that I have seen with this model is reading low pF value caps. Other than that it is up to all amp-related tasks.