Pavel Dudek's super Gainclone group buy

[torb]

I got 2 PCB's as well yesterday, thanks!

Before I begin soldering: To power by DC but build complete, stock PA-03 boards, would it work if I connect my DC source to the ~ terminals of the bridge rectifier? What I think I don't understand is if the delayed-on circuit could cause trouble if it doesn't receive AC-pulses to count.

 

[peranders]

If you don't have 50/60 Hz AC in, your delay circuit won't work but it's not that hard to create an oscillator for that.

 

[torb]

If you don't have 50/60 Hz AC in, your delay circuit won't work but it's not that hard to create an oscillator for that.

Thanks again!

 

[peranders]

All boards are shipped now. Don't forget to report your projects. Pictures and reviews wanted.

 

[Andreas B]

Thank you Per-Anders for the pcb. Soon, I will make an order for yours JSR03 and JSR05 pcbs

 

[peranders]

The market is probably saturated by now with 500 PA03 boards out there but if you sign up on the queue list I might consider one more group buy.

 

[polaron]

Hello Per-Anders!
I realised that I forgot to ask you 8 inductors for my 4 boards...
I tried to find it in the wiki page but didn't find it there.
Could you please send me a paypal invoice and the specifications of it?

Also... what do you think about populating the boards with Dale RN55D resistors?
Thank you!

 

[Kaplaars]

Hello Per-Anders!
I realised that I forgot to ask you 8 inductors for my 4 boards...
I tried to find it in the wiki page but didn't find it there.
Could you please send me a paypal invoice and the specifications of it?

Also... what do you think about populating the boards with Dale RN55D resistors?
Thank you!

Specs: Inductor, 0.7-1.5 uH, 15 turns Ø1.3-1.4 on dia Ø8.

Here you can find are all the documents:

Docs

Schematics

BOM

Made some progress yesterday Can't wait to power it on!

 

[polaron]

Thanks Kaplaars.

 

[czesio]

Hi Per-Anders,

I got the boards yesterday. Thank you very much!

 

[Kaplaars]

Made some progress today . The board is almost completely done. However, I still have to order a mica insulation sheet for the LM4780 and to solder the two voltage regulators to the board. In addition I will add two extra spacers to attach the heatsink even more firmly to the PCB. There are already a few holes for that in the PCB. I changed the layout for the heatsink a bit. This way the cabinet can still be 'low profile' and does not have to be that large in size.

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An externally hosted image should be here but it was not working when we last tested it.

 

[peranders]

Looks very nice but the cooling arrangement could be a setback. The thin profile you have might be too thin.

 

[Kaplaars]

Thanks PA! I was also doubting about that. When I have found an appropriate transformer and are going to test the PCB I will monitor temperature under max load. Worst case scenario I will order a thicker U shaped aluminum profile .

 

[Kaplaars]

Update: I was searching in my 'junk box' for some parts when I saw a nice U shaped piece of 5 mm thick aluminium. So after some drilling and tapping some new M3 holes the PCB has been improved . I have also added two spacers for extra stability.

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An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

 

[loafimus]

Looks good. Your photography game seems to be on par with your project building skills.

I like the VU Meter in some of your other projects.

 

[Kaplaars]

Thank you ! Also for this project I am thinking of adding VU-meters, but I first need to find a nice cabinet. To be continued...

 

[semmyroundel]

Group buy

Very nice implementation of the heatsink, I was thinking along the same lines as I was searching for a suitable enclosure, to mount the board horizontally narrows the choice of enclosure.
Hence the cost goes up.
Incidentally, PER, if you're reading this, I'd like to go ahead with the white PCB but your inbox is full.
Good show everyone!

 

[Vunce]

I received the boards yesterday,
Thanks again P-A!!

 

[torb]

Hi! Quick question:

In the elfa BOM, C2, 3, 6 and 7 (68pF, 500V) are listed as article no 65-862-00, which turns out to be 47 pF 100V.
C9, 16 (47pF, 500V) are listed as article no 65-862-26, which turns out to be 68pF, 100V.

My bad for not reading properly what I ordered, so now I have slightly wrong parts.

My questions are:
Is the lower voltage rating ok?
If so, since I ordered just enough parts, is the small difference in capacitance vary important or can I just put the 68pF ones where 47pF ones would go and vice versa?

Otherwise my build is progressing nicely, heat sinks tapped without incident=)

Best regards!

 

[peranders]

47 or 68 pF is not critical. You can leave it as it is but it's important that you keep the symmetry. Voltage rating is OK with 100 V.

I have updated the BOM for ELFA.