Drip Dual-STA PSU build

[morls]

Hi there,

I've just finished building the power supply for this project. I followed the errata posted on the Drip site, as well as some new docs posted by Gregory last month updating the info on resistors and fuses. I'm skipping the on-board regulators, and will instead rely on the regulators on each channel. I've really taken my time with this, as 600V makes me very nervous. I thought I'd post pics here, if anyone sees something that looks wrong please let me know!

I haven't figured out whether I need the diodes AND relays on the XLR i/o PCB. Can anyone help?

Next step is saving $$$ for the Sowter transformers. The main boards are done, as well as both control boards, got all the SMA cabling sorted, case is finished, so it's really just tubes, transformers and VU meters now...

 

[morls]

Another pic...

 

[morls]

And one more...

 

[FarisElek]

I successfully built this and use it all the time. Your psu looks fine.

Use diodes and relays. The diodes are a precautionary thing. They're not necessary but I'd throw them in there incase you accidentally send phantom into your sta level or something weird. Probably unnecessary but might as well.

 

[morls]

Thanks for that. Is it 1N4007 diodes?

Did you have to adjust the trimmer resistor next to the voltage regulator? I'm hoping the trimmers on each channel's regulator will take care of any voltage adjustments.

 

[FarisElek]

1N4007 will work great. Once you have the psu hooked up, you adjust the trimmer so that the heater power supply reads 6.3v. That information is definitely on the manual.

 

[JMan]

Any advantage to using the regulators on each channel rather than the onboard regulators on the psu?

 

[morls]

The main reason is to keep the temperature down, which is also why I went with diodes instead of the 5AR4.

Just heard back from Gregory, the diode recommended for XLR i/o board is 1N4148

 

[JMan]

The main reason is to keep the temperature down, which is also why I went with diodes instead of the 5AR4.

Just heard back from Gregory, the diode recommended for XLR i/o board is 1N4148

Ah, good call. 

Also, what were the new docs that you mentioned that Gregory posted?  With his new website (which is much tidier than the old one), I didn’t think he had the docs linked up yet.

I won’t build this for quite awhile yet, but when folks discuss it, I take notes.  Hoping it will help things go smoothly whenever I eventually get around to it.

 

[morls]

Also, what were the new docs that you mentioned that Gregory posted?  With his new website (which is much tidier than the old one), I didn’t think he had the docs linked up yet.

The documents are here:
https://ws.onehub.com/folders/4t55esf8

 

[FarisElek]

The main reason is to keep the temperature down, which is also why I went with diodes instead of the 5AR4.

Just heard back from Gregory, the diode recommended for XLR i/o board is 1N4148

The 1N4007 is over qualified for the job but works. I used them because I had a bunch of them in my drawer.

 

[morls]

Hi Moris,
I am currently building a 2012 DRIP Sta Level (the big PCB), and was wondering if you built this one also?
The board uses the Hammond 270FX power transformer according to the BOM. Unfortunately the build manual, which is for the dual Sta Level, uses another model. I can't figure out which wires go where on the board.
We mailed Drip a few times and at first he was fairly responsive, but total silence now since a good month and a half..

Hope you can help me out!
Many thanks in advance,
best,
Kees

Hi Kees,
I built the Dual STA, so I'm not familiar with the single PCB build. Do you have a schematic of the PSU for your build? I know the Drip PSU design has changed, and that the one I used for my Dual STA is a kind of generic board that is used for a few different Drip builds. There are changes made to components in order to get the correct voltages for each different project. I imagine your PSU would be an earlier version, which isn't something I have any experience with.
See if you can track down older build threads for this version, there might be some documentation floating around that could help. If you could get a circuit of the PSU you could then figure out the connections, using the 270FX wiring documentation.
I don't want to offer any advice about wiring up, other than to suggest you get all the documentation you can find and ask someone with the experience and knowledge to be able to help. I'm very wary of PSUs
I'm happy to help where I can!
Cheers
Stephen

 

[LilHeaven Studios]

Hi Kees,
I built the Dual STA, so I'm not familiar with the single PCB build. Do you have a schematic of the PSU for your build? I know the Drip PSU design has changed, and that the one I used for my Dual STA is a kind of generic board that is used for a few different Drip builds. There are changes made to components in order to get the correct voltages for each different project. I imagine your PSU would be an earlier version, which isn't something I have any experience with.
See if you can track down older build threads for this version, there might be some documentation floating around that could help. If you could get a circuit of the PSU you could then figure out the connections, using the 270FX wiring documentation.
I don't want to offer any advice about wiring up, other than to suggest you get all the documentation you can find and ask someone with the experience and knowledge to be able to help. I'm very wary of PSUs
I'm happy to help where I can!
Cheers
Stephen

Hi Stephen,
thanks a million for your reply!
I've been able to track down a couple of pictures of similar builds. Together with the 270FX documentation my tech should be able to figure it out (I hope).
Our biggest issue is that Greg thought he could remember a mistake on the PCB, but wasn't sure if it was the single or dual version. Considering the Errata on the dual PCB version, we're hoping it was the latter .

Cheers and will let you know how we get along!
Kees

 

[morls]

Hi Kees,
Glad to hear you're making progress. One other thing you might need to look out for is the heater supply. I built a couple of Drip's Pultec clones (similar era to your STA I think...), and had to add a rectifier to the PSU. The heater supply on these boards was AC, and there were noise issues with the layout that having a DC heater supply went a long way towards fixing. This is one of the things the revised power supplies fixed up, so it might be worth checking whether the earlier STA PSU puts out an AC or DC heater supply.
Stephen

 

[Beeswax]

Ah, good call.

Also, what were the new docs that you mentioned that Gregory posted? With his new website (which is much tidier than the old one), I didn’t think he had the docs linked up yet.

I won’t build this for quite awhile yet, but when folks discuss it, I take notes. Hoping it will help things go smoothly whenever I eventually get around to it.

I'm gearing up for this build. Wondering about the tonal characteristics of the diode vs 5AR4? And does anyone have a Mouser or Digikey cart for the main board?

 

[Riinehart]

Hi all. I'm getting started on a Dual Sta build, and right away I've realized there's been a change to the PSU.

Attaching a photo. It's two separate boards, as opposed to what you see in morls first post in this thread.

I can't find any documentation for this configuration. Has anyone built a recent Drip project using this PSU? Anything I should know? I'm not even sure what the best configuration will be to fit these on the back panel of my case.

I've emailed Drip for support, but judging from many other threads it seems unlikely I'll get much in the way of a response.

Thanks very much for any help!