Princeton Reverb B+4 no voltage (D).

[heave1]

Finished my Princeton Reverb build and there is no Voltage at the Cap can at (D) or B+. A+, B+ and C+ all have the proper voltage.
The cap can shows the correct capacitance values.
No plate voltage to V1 or V2.
I have continuity in the under board D wires, but voltage isn’t getting to V1 and V2.
I used Rob Robinette’s suggested Mods layout and schematic.
Here is the layout.
Any help appreciated.

 

[dan40]

Are all of the tubes including the rectifier lighting up and getting warm? With all of the tubes removed except for the rectifier, start working your way through the power supply with your meter. The two red wires from the PT to the rectifier will be an AC voltage reading. Pin 8 on the rectifier will be a DC voltage reading. Check both of these two points and report back with your voltage readings. From pin 8, follow the schematic and check the DC voltage at each of the filter caps in the power supply. If you come to a node that doesn't show voltage, you can then look for a missing wire, wiring error or bad solder joint.

 

[Wally]

Here is a schematic for a Princeton Reverb…

https://schematicheaven.net/fenderamps/princeton_rev_gz34_aa1164.pdf

imho, reading a schematic gives one a better understanding than does a layout.There is also a rough guide of what voltages 9ne might expect to see.

I take it that you have voltage at the A,B, and C posts on the cap can, correct? If so and if you do not have voltage at the D post in the can, check that dropping resistor between C and D. If it is open, then you will not have voltage at D. If the resistor is not open, then the problem is more intriguing.

 

[heave1]

I am a complete idiot. I left off the 18K resistor across C and D. Thanks for the heads up. It works great now, getting voltage.
Now to check the power tubes.

 

[heave1]

Are all of the tubes including the rectifier lighting up and getting warm? With all of the tubes removed except for the rectifier, start working your way through the power supply with your meter. The two red wires from the PT to the rectifier will be an AC voltage reading. Pin 8 on the rectifier will be a DC voltage reading. Check both of these two points and report back with your voltage readings. From pin 8, follow the schematic and check the DC voltage at each of the filter caps in the power supply. If you come to a node that doesn't show voltage, you can then look for a missing wire, wiring error or bad solder joint.

Thanks. I left off the 18K resistor across C and D. Works okay now.

 

[Wally]

I am a complete idiot. I left off the 18K resistor across C and D. Thanks for the heads up. It works great now, getting voltage.
Now to check the power tubes.

So, there was infinite resistance between those two caps? (;^) We all make mistakes.
In “Zen and The Art of Motorcycle Maintenance”, Robert Pursig addresses the ‘trap’ that ensnared you in not seeing that error. We must never accept that our work was correct. The book is worth reading for many reasons, imho.

 

[schmee]

Seems there is always one obvious thing when you build an amp from scratch. I'm about to light one up right now, wish me luck!