Bottlehead Kits > Mainline

Mainline Voltage Check

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FS:
Hi Paul,

I have checked the identity and orientation of every single piece on the power transformer board. I have re-soldered every single piece on the power transformer board for a total of 3 times, re-flowing the solder and holding for 10 seconds, then letting it sit for a few seconds before proceeding to the next. I have also resoldered every connection to the power transformer, and the wiring from the switch to the power entry. I have done the voltage check as indicated on page 38 of the manual (no tubes). I am still unsuccessful in getting a voltage higher than 5.33V between the -6.3V and the +6.3V pads. Any additional thoughts? What else could I try? Thanks.
Falko

Paul Birkeland:
You'll also want to be sure the 10uF yellow capacitors are oriented properly.  Next, measure the DC voltage on the banded end of either 1N5820 next to the label "275vDC".

FS:
Hi Paul,

The DC voltage at the banded end is 10.2V for each of the 1N5820 closest to the 275V DC pad.
Voltages are 4.8V and 4.7V, respectively, at the banded ends of the other set of two 1N5820.
F.

Paul Birkeland:
Are you 100% certain that there's a 1085 regulator mounted to the heatsink and not an MJE5731A? 

Your resistor values look right, so if one of those 10uF caps isn't in backwards, it's difficult to determine what is pulling your voltage down so low.

FS:
Hi Paul,

It says LM1085 on the part that has the heat sink.
I am pretty sure that I have put the orientation sensitive tantalum caps in the right orientation, but can't check that as I had trimmed those leads after soldering.
I have measured the voltages at the 10uF capacitors. On the one closer the the 6.3V pads, it reads 5.33V on the +, 0V on the -, the other cap has 0V on the -, and 10.4V on the + side. Are these values correct?
Thanks,
Falko

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