UGS-muse preamp GB

[aterren]

Any recommendations for the power transformers for eric's power supply setup?

This is important given some users have 120v mains and others 220v.

 

[redjr]

The final version is 288mmX288mm and i will order soon 10 boards around 34$ each.
I had PMs from some off you who are interested. Please confirm.Thanks

I'm still in for 1 board.

 

[PsykoK]

This is important given some users have 120v mains and others 220v.

indeed it will be two type of transformers


My idea was more if we should look to organise a GB for the transformers in Europe. Not sure if it’s really worth it or not.

 

[potepuh]

If we organize a GB for the transformers in Europe, the toroidy is a candidate for them. We should organize in a way that we pay only one final shipping (components and transformers together).

I am interested.

 

[PsykoK]

that exactly why I'm asking to maybe add the transformer to the already open components GB

 

[PsykoK]

I have been thinking to use for the project transformers from Toroidy.
They have 2 interesting models that can suit our project: audio grade and supreme.
I have sent them an email telling about my interest and also the potential interest from here asking if there is possible any discount if we buy more units.
I have considered that for a preamp we will need 1x9v trafo and 2x 22v trafos each of them with dual secondaries. As VA ratings I have considered 30va and 40va.
My idea was to gather 20 persons here that would want to buy a set of audio grade or supreme trafos so we get to a total of 60pcs and each of us will do the order directly to them so we don’t have to send the trafos to a person and this person redistribute them to the others. I also have told them that a part of us are from europe and the other from the usa.
After sending the email Tomasz replied shortly to me saying that if we order a total of 60pcs(audio grade and supreme) we can get a discount coupon that each of us can use to get a 5% discount on the order but this is valid only from the people living in europe.

Here are the prices for which we will get 5% discount:



Audio grade (potted interior + neoprene mounting pad included):

TS30VA PRI: 230V SEC: 2x9V - 23,80 EUR / pc (23% VAT tax included)
TS30VA PRI: 230V SEC: 2x22V - 23,80 EUR / pc (23% VAT tax included)

TS40VA PRI: 230V SEC: 2x9V - 24,70 EUR / pc (23% VAT tax included)
TS40VA PRI: 230V SEC: 2x22V - 24,70 EUR / pc (23% VAT tax included)

Supreme version (potted in the stainless steel box):

TS30VA PRI: 230V SEC: 2x9V - 64,70 EUR / pc (23% VAT tax included)
TS30VA PRI: 230V SEC: 2x22V - 64,70 EUR / pc (23% VAT tax included)

TS40VA PRI: 230V SEC: 2x9V - 65,80 EUR / pc (23% VAT tax included)
TS40VA PRI: 230V SEC: 2x22V - 65,80 EUR / pc (23% VAT tax included)

Supreme version + side wiring plate:

TS30VA PRI: 230V SEC: 2x9V - 73,50 EUR / pc (23% VAT tax included)
TS30VA PRI: 230V SEC: 2x22V - 73,50 EUR / pc (23% VAT tax included)

TS40VA PRI: 230V SEC: 2x9V - 74,60 EUR / pc (23% VAT tax included)
TS40VA PRI: 230V SEC: 2x22V - 74,60 EUR / pc (23% VAT tax included)

You can find pictures of the transformers here: https://sklep.toroidy.pl/userdata/public/assets//Transformers grade comparision.jpg

What do you think about this?

if found it

 

[schultzsch]

I have ordered my trafo at Toroidy. It takes a month to build the transformer so it would be best to decide asap cause else I think you will have them the next year.

 

[Boydk]

OK.... I´m in for one of each 40VA Supreme Version. Just add me to the Google sheet, if you decide to do the GB (PsykoK)

 

[PsykoK]

I got a quote from Toroidy this afternoon for a ingle transformer with the following specs:
TS 50VA PRI: 230V SEC:
4x 24V@6VA
2x 9V@9VA

Audio grade transformers: 48,00 EUR/pc (23% VAT included)
Audio Supreme version (without side wiring plate): 94,00 EUR/pc (23% VAT included)
Audio Supreme version (with the side wiring plate): 102,00 EUR/pc (23% VAT included)


I don't know jet what could be discount if we do a GB, I will ask on monday

 

[Boydk]

Probably even better... spacewise

 

[PsykoK]

I have added the Transformer option to the GB

 

[schultzsch]

When I asked about the discount for the groupbuy they said that they can do 5%

Forgot to mention that I paid 120€ for a 100VA supreme

 

[redjr]

I've been doing some testing on my main PSU board and can't get the desired +- voltages. Per a post by Eric awhile back, he provided a diagram that mentioned you need to tie GND-R and GND+R together when going from the Phoenix connectors on the PSU, to the 3-pin connectors of the regular PCB.

Therefore, according to the PSU schematic I tied those (pins 1) together and still cannot get a negative voltage (-46), as would be expected if I tested with my DVM. Shouldn't I get a - and + voltage relative to the GND? I get the correct positive voltage(+46), but if I leave the negative probe on the tied together GNDs, I still get only the positive voltage regardless of which rail I measure. At the moment, I'm not planning on using the DB15 connector.

First of all, do I have the wiring correct shown in the attached image below? I'm obviously doing something wrong, or miss-reading the schematic. I did notice a difference between the Left and Right channels of the PSU, but I think it was just some miss-labeling when it was originally laid out.

Sorry for such a basic question.

 

[schultzsch]

I think you need to swap black with white wires on the left connector

 

[Boydk]

"I think you need to swap black with white wires on the left connector"

Yeps....... that´s it . The + on the left connector is to be viewed as GND

 

[redjr]

Thanks guys, that did it. However, I think the markings on the schematic may need to be revised. Clearly, pin 1 on the left connector (J12) is shown as tied to GND-R and pin 2 to V-R. I hope I haven't damaged the one completed Salas Shunt due to this. Further testing now to check. If you look at the L-channel rails on the schematic, the markings are different.

 

[Alex_twn]

Yes you are right, I just checked the schematics and it looks like there is a little problem here with the net labeling on the right negative rail.
GND-R and V-R seems swapped.

Sorry about that.

If you connect as it is you should have 2x positive rail, hopefully your negative Salas shunt did not suffer from this...?

To all please hold on while we provide a corrective, I am going to check with Eric.

 

[Alex_twn]

Regarding the GB, everybody finally received their PCB kit except 2002tii.

@2002tii, your PCB are still at Eric's home, please provide your address as soon as you can for re-shipping. Thanks.

 

[Eric06]

Thanks guys, that did it. However, I think the markings on the schematic may need to be revised. Clearly, pin 1 on the left connector (J12) is shown as tied to GND-R and pin 2 to V-R. I hope I haven't damaged the one completed Salas Shunt due to this. Further testing now to check. If you look at the L-channel rails on the schematic, the markings are different.

Oops, indeed my mistake. I picked up and inserted the wrong schematic when I created the overall documentation for this board.
Here is already the schematic that matches the PCB that you have received.

The full spec will be revised later on (tonight hopefully if I managed to recreate my usual working setup as my main PC died a week ago).

Deeply sorry for the trouble and I hope your negative Salas regulator didn't get damaged by this polarity inversion.

 

[redjr]

Thanks Alex & Eric. Just needed to make sure I wasn't going crazy. I try to double-check everything first! Thanks for posting the revised/correct schematic.