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Re: Internal power supply and PSU mod

Posted: Aug 10th, '15, 13:40
by xlarge
The upper 15AC will be connected to the D1 anode.

I wonder though; 0v is that connected to 220v GND? (I mean, chassis is connected to gnd and pots and what not will touch schassis).

Re: Internal power supply and PSU mod

Posted: Aug 10th, '15, 20:53
by gihaume
Thank you for your reply !
xlarge wrote:The upper 15AC will be connected to the D1 anode.
OK, thank you ! I was thinking that would result 15 + 15 = 30 V

I didn't understand the question in your second sentence...

Re: Internal power supply and PSU mod

Posted: Aug 11th, '15, 12:23
by xlarge
It will.

You want:
+15V referenced to 0V
-15V referenced to 0V
potential difference is 30V


My question about gnd and 0V was aimed at the originator of this mod. :) I've pm:ed that person to but no answer as of yet.

Re: Internal power supply and PSU mod

Posted: Aug 13th, '15, 11:45
by jeroenbvo
Hi xlarge,

Sorry for the late reply, I didn't spot the pm... :oops:

So, the 230V gnd will be wired to the chassis. I used one of the mounting screws of the C14 socket. The 0V connection goes also to there via the loop breaker.
See pictures 8-10 on the Imgur album: http://imgur.com/a/IeBch#8

Hope this helps.

Kind regards, Jeroen

Re: Internal power supply and PSU mod

Posted: Aug 13th, '15, 14:13
by xlarge
Kickass, thanks Jeroen!

Re: Internal power supply and PSU mod

Posted: Sep 25th, '15, 18:08
by electricmonk
What is the transformer part number (which shop was it bought from) in the original post?

Re: Internal power supply and PSU mod

Posted: Sep 27th, '15, 12:33
by Altitude
I used this: http://www.digikey.com/product-detail/en/0/1295-1065-ND

Make sure that whatever you choose has 2 15VAC secondaries and at least 15VA

Re: Internal power supply and PSU mod

Posted: Sep 28th, '15, 09:47
by jeroenbvo
I ordered my transformer at Reichelt at the time. You need indeed 2x 15VAC with atleast 500mA per secondary.

Re: Internal power supply and PSU mod

Posted: Sep 30th, '15, 06:49
by deejayraoul
EchoBoy wrote:@deejayraoul: Did you keep the external supply option to make a SNR comparison between external and internal supply?

I did not have time to investigate on my hum issue yet. Sorry Jeroenbvo for not having replied earlier.
In my case the hum is present on all outputs, whether instruments are played or not. This hum also exists with the external supply but >10dB quieter which makes it acceptable.
For now I suspect radiation from the toroidal transformer.
I kept my external power supply, didn;t do any scientific comparison, but it was obvious.
I gues i need to
find a shieldedtransformer (wich would be quie hard as the transformer hardly fits in the metal case at the moment)
ór
find a way to shield this transformer (does anyone know of a safe way/material to do this?)
ór
deal with the noise
ór
go back to the external power supply.

Re: Internal power supply and PSU mod

Posted: Feb 13th, '16, 23:31
by rv0
i have 2 yoctos here, exact same internal psu, using similar connection like discussed in this topic. one has very loud interference on the congas, the other is a bit less, but its still there.
Listen here: https://soundcloud.com/rvooh/david-yoct ... se/s-tdo8y (I go from LC to MC, then HC, each time i turn tune from min to max)

Doesn't anyone have a working solution for this by now?