Problem with Integration upgrade [resolved]

[cpditter]

Hi:
Just finished the Shunt Regulator board and one of my LED's is not working...Not sure what to check to see what is wrong.

Pic attached.

thanks
Chuck

[Paul Birkeland]

There's a voltage check on page 23.  Can you let us know what you get for that voltage check?

I see lots of long leads poking out of the top side of that board, which makes me want to see what's going on underneath the board as well...

[cpditter]

Sorry that was sloppy, I just did not snip the leads on the connection wires from the preamp...did now.  Pic of underside attached.

voltage readings in order of the manual:
134
144
147

Note, my wall voltage is high...I believe in the 130+ range...
Thanks

[Paul Birkeland]

You may have solder bridging two terminals on the bottom side of that board, and that would cause some of your issues.

You gave me three voltages and didn't assign them to terminal numbers; the manual lists for terminal numbers to check... Did you have 6922 tubes in the sockets when you performed this set of voltage checks?

How about the voltage checks on page 17?

[cpditter]

Hi
Those were the voltage readings on p. 17, so the two MJE5731 readings were 134 and 144, and the terminal 56 reading was 147v

I'll pull the board back off the preamp and take a better pic of the bottom side and will also look for any solider bridging...

Thanks

[Paul Birkeland]

I would absolutely reflow every solder joint on that board other than the LEDs as well.

[cpditter]

OK
I think I found a solder bridge between two pins of the MJE5731 on side B...fixed that with some solder wick.  Reflowed most all the joints.

Reconnected and now all 4 led's light.

Voltage readings from p 17 are now as follows

MJE5731 are 123 and 124v
Terminal 56 now 127v

Good to go?

[Paul Birkeland]

No, the tabs on the MJE5731As should read lower than terminal 56.  Can you post some photos of the power supply and where you have the extra 1K resistors installed?  Also you didn't mention whether you had the 6922s installed, but I would recommend installing them if you do not have them in already, then repeat these tests. 

[cpditter]

Hi
Yes, tubes are in.

Photos requested attached, let me know if you need more.

Voltage at tabs on MJE5731 are lower than term 56...but not enough lower?

Again, readings on the transistor tabs are 123v and 124v and readings at term 56 is 127v

Thanks

[Paul Birkeland]

All of the joints in that photo should be reflowed, possibly with a little more solder added.  Heat them up till the solder liquifies, then wait for it to flow where it wants to flow.  It doesn't look like the flux has flowed out of most of those joints.

[cpditter]

OK, will do that tomorrow...thanks for the quick responses as always!

[cpditter]

Hi:

Well, I reflowed and added solder to pretty much all the connections on the unit as well as the new board,
Readings as follows

A-side MJE731: 123v
B-side:  124v

Terminal 56:  127v

[Paul Birkeland]

What voltage do you get at terminal 50?

[cpditter]

Hi
Terminal 50 is 146v

p.s.  Not sure if you saw in earlier post, or if it matters, but I know my wall voltage at our house is high...I believe close to 126-127v

[Paul Birkeland]

How about 53? 

The wall voltage isn't particularly concerning.