Heater voltage is off [resolved]

[Larpy]

I finished the power PCB and installed it above the PT.  Did the measurements per the instructions and everything checks out perfectly except for the 6.3 V reading.  I'm getting 11.5 V DC.  Is that alarmingly high?

[Paul Birkeland]

Yes, like the regulator isn't doing any regulating.  Can you post some photos top and bottom of that board?  Also triple check that the 1085 is on that board and not an MJE5731A.

-PB

[Larpy]

Found the problem!  I missed two solder connections, at one leg of the 124Ω resistor and at one leg of the 499Ω resistor.

Just goes to show you how easy it is to miss what's right in front of you.  Thank you for confirming that there was a problem and that it was probably something concerning or the nearby the 1085 regulator.

[Paul Birkeland]

I'm pretty sure you did all the work here, I'm glad you got it sorted out.

[maarten]

Hi,

I had the same problem and did indeed accidentally install the MJE5731A instead of the 1085
I assume it's ok to just swap it out and I have not broken it?

[Paul Birkeland]

You can set your meter to beep for continuity and check each pair of legs on the 5731A to be sure none of them are shorted together.