My_Ref Rev.C power supply

[Jordan Roy]

Hi guys!

I will soon have the My_Ref Evc.C pcb done. I am now searching for a solution for the power source.

I would have access to one of those, (the LCA), power supply for the alimentation part, and cheap. Do you think it would fit? It is an LAMBDA industrial regulated power supply, capable of 2x24v secondary.

Also, I have started to read the MyRef thread to find what is the correct way for the power source, but there's way too much info.

Anyone could tell me clearly what is that design requirering as transfo or PSU?

Thanks a lot!

Jordan

[Nordic]

DId you make your own PCB cause those boards each had their own PSU onboard, all you needed was a transformer or two...

[Jordan Roy]

Yes I made my own, based on the Twisted Pear's site PCB.

So, for the MyRef Rev.C, all I would need is a 24v secondary transfo? Does it absolutely have to be 24v? And what is the seggested primary VA ?

Sorry about the noobness of the questions, but I searched a lot, and found no clear answer...


Regards,
Jordan

[Nordic]

again speaking from memory 160VA for seperate trafos, and 250- 300 if you are going to share one...

As long as you don't go to far above or below 35V after rectification you should be ok until you turn the knob almost to the end. so feasably 2 x 22 to 26VAC secondaries could do the trick.

As a recommendation, there are 2 1W 1k resistors, you need bigger wattage for those... try a 2W it gets very hot, also make sure the zener diodes are not flush with PCB so that air can circulate around them.

We just need to wait for Russ or Brian, I am too lazy to go look if their circuit included the PSU bit...

Do you see any transistors in your schematic?

[Jordan Roy]

Thanks for your info on this! Really appreciated.


Here is the schematics




Jordan

[troystg]

If you made the twisted pair kit then all that is required is the transformer as Nodic stated.

Mine sounded great straight off the soldering bench! Good luck with yours..

[Panelhead]

Troy,
When did you leave the great state and go back home?

George

[BrianDonegan]

If you etched your boards from the mono block images Russ posted, the power supply is included on each board, along with the speaker protection circuitry.

All you need is a trafo, as mentioned earlier. 24V is the ideal. 25V is fine as well. I actually recommend higher than 160VA per channel. I recently build a couple RevCs using a 250VA for a pair (buyers choice) and the rails do sag quite a bit at higher output levels. 250VA per channel or 400 for a pair would be ideal.

I think Antek (ebay seller) has 400VA 25V torroids for not too much. [EDIT: Doesn;t appear to have any right now]

[Nordic]

The schematic is not complete, the PSU and DC protection parts are missing.... however the monoblock PCB as said above will need these parts too..

[BrianDonegan]

The schematic is not complete

Correct. Mauro initially drew the RevA as a 2-page schematic. RevC revisions were only to the first page, which is what you see there. The second page, with power supply and protection circuitry is present in the schematic.

You can see the whole thing here: http://www.diyaudio.com/forums/attac...amp=1116856847

from this post:
http://www.diyaudio.com/forums/showt...939#post647939