Princeton Reverb Gerber Files

[Heikki]

I recently made a Princeton Reverb with couple minor tweaks. Here are the gerber files for the pcb if anyone wants to use them. http://ghr.fi/guitaramps/trinceton/prin ... 50x110.zip

Schematic and layout attached

Here is a sound sample we recorded:

[Guy77]

Beautiful work and great sounding amp!
How do the preamp tubes plug into your board? Is there a special socket .

Congrats!

Cheers
Guy

[Heikki]

How do the preamp tubes plug into your board? Is there a special socket .

Noval PCB socket

[Guy77]

Thank you Heikki!

Cheers
G

[steve07868]

quick question

What is R39 for and what do you have in there?

I cant tell from the pics

Steve

[pompeiisneaks]

I can't see the value written anywhere, so yeah what 'is' R39, it's a dropper resistor that takes the place of the choke on some builds, basically taking the input voltage post rectification down a notch before the first filter cap.

~Phil

[steve07868]

Great project I finished my build over the weekend amp works great and is dead quiet
I used r39 for my standby switch I also did not have those fuse holders so jumped over them
really cool project I used a really big chassis 17x10x2 but I had lots of room to mount the board and
not have to cross mount any transformers thanks again for the gerbers

[Heikki]

What is R39 for and what do you have in there?

R39 is optional "sag" resistor. You can put put 50 - 100 ohm 10W resistor there or if you don't want to use it just put a jumper over it or put stand by switch there like you did. I used NTC thermistor there as R39 to limit inrush current so I don't blow my B+ fuses at start up.

[ViperDoc]

Thanks for posting this, Heikki.

Do you recall what your B+ was coming out of your rectifier diodes/at R39?

[Heikki]

Do you recall what your B+ was coming out of your rectifier diodes/at R39?

As I recall in my amp B+ is about 390V. For anyone building this what your B+ voltage is going to be is going to depend on the power transformer you use, but B+ anywhere between 350V - 420V should be fine. If it's in that range there shouldn't be huge impact on tone.

[ViperDoc]

Thank you, Heikki. That's what I'm shooting for, but I'm about 50 volts too low at the moment. Working it out...

[VolkerStaub]

since there's so many iterations of the Princeton, which exact model is this made after?
and is there a way to add a master volume to the circuit so I don't have to evacuate the house if I want some chrunchy to overdriven sounds.
and lastly, what transformer did you use for your build?

[erwin_ve]

since there's so many iterations of the Princeton, which exact model is this made after?
and is there a way to add a master volume to the circuit so I don't have to evacuate the house if I want some chrunchy to overdriven sounds.
and lastly, what transformer did you use for your build?

There is a schematic and layout in the opening post.
The original poster was last active in 2021, it may take a while to get a response.

Best,

Erwin