PCB Power Board Fabbed

[Decko]

Hi All,

Wanted to share this new sub assembly.

For me, the traditional method of gluing power caps and wiring the B+ voltages to the preamp board was time consuming and cumbersome.

Lou Rossi designed up some art work for me and I fabbed a board in my garage.

Here is the result.

Decko

[Cantplay]

I've always thought that a couple of multi part twist lock can caps standing on the chassis would be a better way to go.

Looks good though.

John

[rock_mumbles]

Nice work!

[M Fowler]

I can see that becoming a standard item in Trainwreck builds.

Very nicely done.

[Decko]

Thanks for the kind words!

The idea orginated from George who used a CNC machine to create the traces.

On this board I added the first 1K dropping resistor, the standy connection, the rectifier connection, the center tap, the bleeder resistors and a configureable option for a low power Wreck (10 watts) or higher power Wreck 35 watts.

This particular board is a low power Wreck.

Regards,
Decko

PS: If anyone wants one, I may be open to running a few boards for a nominal.
Let me know

[hans-jörg]

Hi,
very nice PSU.
What is the overall height? Under 5 cm? I guess over.

Best

Hans-Jörg

[Bear]

Looks like a solid idea, kind of like the Dumble "Precision" power supply.

I'm used to PCB's for pedals -- any special concerns for selecting boards for very high voltages?

[M Fowler]

The main thing is either larger eyelets for hookup or multiple eyelets on same trace especially where two - three hookup wires meet.

This board is built to fit a 2" TW style chassis I'm guessing?

Mark

[Aurora]

The idea is good, - better than the glue stack, indeed, but from a POV of constructive criticism, I don't like those power resistors crammed in between those caps.... a little heat trap, when the board is mounted upside down..... how much power is deposited here....?

BTW- I grew up with tube TV sets, and is generally quite wary of power resistors on PCBs......

[Decko]

The overall height of the board is less than 50 mm or 2 inches...the package was engineered to fit into the standard Wreck chassis. In fact I designed the board to fit within working envelope as the original Ken Fisher layout (TC75 and TC78s stack). Current size is 60mm x 50mm.

The idea is similar to the D style power supply. According to my PCB designer, I was told that the single sided 1 oz copper boards could handle the power and voltages for this prototype which will be for the low wattage Wreck. However since the board is also designed at a component level for the high powered Wreck as well, I will ask if there will be any issues with the high voltages and/or heat generation cause mainly by the cement resistors or the other cement dropping resistors commented on by Aurora.

Mark, eyelets are a good idea! This is rev 1, I will add that to the second rev!

One more comment on the 1k 5 watt cement resistor: could anyone recommend a heat sink type resistor? The issue is the overall height should be less than 50mm or 2 inches. I am mounting the resistor upright.

Decko

[steve_p]

Because you are integrating the cement resistor, caps and dropping string right onto this board, you don't necessarily need it to fit exactly where the cap stack generally goes, correct?

If you wanted to get really fancy, you could layout 1 board that combines all your elements, plus the diodes and bias circuit. This would probably allow you to spread those power resistors out a bit to allow for better airflow.

Steve

[vibratoking]

Either way, heat rises and the Wreck is a flipped chassis. Where does the heat escape in a 'normal' Wreck? Yup, through the chassis. Same place it will escape in your design. I wouldn't think twice about it.