The Aleph30 PCB layout

[Peter Daniel]

The IXYS bridge is connected to the bottom of copper plate. If it overheats, I will attach more dissipating surfaces. Now you know why I don't favour PS boards

[BrianGT]

Originally posted by Peter Daniel
Before I start sending the boards out, I have to test them, so today I was working on a power supply. Here what it looks like: 500VA Plitron is on the bottom, in its own enclosure. The Sikorel caps above (22,000/50) have ground terminals connected by 1/8" copper plate. This PS is for two channels, each channel having a pair of caps connected directly to a bridge.

You can see heatsinks in a back.

Looks really nice. I look forward to seeing how the final amp will work out.

What voltages is your transformer putting out?

--
Brian

[Peter Daniel]

The transformer is putting 30V without load (it is 20V AC).

Here's how the boards are mounted on a heatsink ( on both sides). There is one more plate, covering the front. If not enough cooling, I will attach a fan on top (which I think will be necessary).

[BrianDonegan]

The finishing touch will be to have gentle wisps of smoke (not magic smoke) puff from the top. It will look like a nuclear reactor letting off steam.

[nbaula]

Hi! Peter do have any extra board I can buy ?

[Peter Daniel]

There will be enough boards for everybody. I'm ordering more, but have to test the circuit first; hopefully tomorrow.

Drop me an e-mail for payment info.

[Peter Daniel]

So the amp is finished, and luckily it works fine. I have to admit that I was a bit uncertain about the outcome, as after all this is not a GC, but a manly amp This is also my first Aleph that does not hum.

The voltage I'm getting on rails is exactly 27.6V DC with a mains at 123V AC. The transformer is one per two channels, Plitron rated 2 x 20V , 500VA. With 115v rails you should be getting close to 25V though. The circuit is exactly from Aleph30 schematic.

[Peter Daniel]

Here's the closer look at the heatsinks I'm using:

[Peter Daniel]

It didn't take long and they were getting pretty hot, so I decided to use a fan. I mounted it on top using double sided tape (in 4 corners):

[Peter Daniel]

The fan supply is run from a separate windings, and by using an dajustable regulator (on the right, beside big caps) one can adjust the speed. It is pretty efficient setup, does not produce noise, and lowers temp. substantially.

The plate that bridge is mounted on, runs cool enough, but differencial pair and const current source mosfet, are quite hot (more than 50 deg) so I will be probably using a strip of copper to lower temp (there is enough space for that).