V3 Universal Power Supply Circuit Board

[tricksters]

PSU

Hi, I designed a mounting layout for the PSU, I wanted to know if the CL60 thermistors are positioned well, is the first inserted on the neutral at the input, or should it be inserted on the Line?
is the positioning of the Capacitor from 0.0033 uF right between L and N?
The second output thermistor connects a PSU ground to the chassis .. is that right?
or is the second thermistor not needed?
(I attach diagram and datasheet of Toroidal)

Thank you.

 

[avitkauskas]

Hi @triksters.

The first thermistor is usually put on the live wire (though it would not make a difference if you put in on the neutral, I think). The capacitor is ok. The thermistor on the PSU ground is also ok. Put the ground wire from the IEC connector to the same bolt on the chassis as the other end on this ground lifting thermistor as well.

 

[myleftear]

If you research a little bit on „earth“ ground „bolt“, you will find quite a few post (of experts) which very clearly state the the earth (from the IEC) must have its own bolt, not even earth bolted (screwed?) separately on the same bolt (screw?) is good. Safety-measures, perhaps legal stuff, not technically…

Just my 2c

 

[avitkauskas]

@myleftear, I'm not sure we talk about the same thing, but I always saw instructions like that: put earth wire on the bolt first and tighten it with the separate star washer and nut - so that when you put other ground connections on top of it (on the same bolt) you should never make loose the earth nut and always have the earth wire properly bolted to the chassis.

 

[tricksters]

Thank you.
I will follow your advice, and connect the IEC ground first to the chiassis, then the thermistor and eventually the other ground, if necessary : D

 

[myleftear]

@myleftear, I'm not sure we talk about the same thing, but I always saw instructions like that: put earth wire on the bolt first and tighten it with the separate star washer and nut - so that when you put other ground connections on top of it (on the same bolt) you should never make loose the earth nut and always have the earth wire properly bolted to the chassis.

Yes we talk about the same thing, and information is conflicting…

In the end, it’s your build = your decision

https://www.diyaudio.com/forums/construction-tips/365789-chassis-ground.html#post6480928

 

[Ground point 9]

Thanks for all the suggestions and help. I've ordered from Digi-Key all (hopefully) of the parts needed to make the PSU and wire it to the F5 and F6 boards etc.. I realize that because it is a "universal" power supply board it is difficult to specify all the parts needed but I do think it would be helpful for a newbie to have a more complete list of the materials needed to build a basic First Watt amp and power supply. The BOM on the DIY Store has some notable holes although I do appreciate the listing of most of the parts. I generated a bill of materials from my Digi-key order so if anybody lurking would like to have that just PM me. I invested at least 8 hours in researching this and I'm guessing that is going to be the least fun part of building these amps.

Amen!

Far too much flexibility in the published BOM for a newbie (me) to take advantage of.

That said, I wish I knew enough to put together one such and submit to this thread... it would be a small token of my appreciation for all the benefit I've derived.

Please share your Digikey BOM if you don't mind.

Cheers!

 

[A Jedi]

I'm shopping parts for a vanilla F5 and was wondering if there's a preferred toroid? I don't mind spending a bit more for a 400 or 500 va (because I'll feel better about it lol). Actually, I wouldn't mind overbuilding for potential future need.

Thanks!

 

[KevinHeem]

Anek AS-4218 is popular and inexpensive (vanilla). Toroidy audio grade is an example of preferred. And you’ll find choices in between.

 

[A Jedi]

Thank you very much.

 

[A Jedi]

Anyone know where I can order a Toroidy? I'm in the US and their website (Toroidy) says they won't ship here.

 

[myleftear]

Get in contact by email. (Make your selection in the store, tell them the configuration you want)
officially , they don't send trannies to me, but if you deal directly, all works perfectly.

 

[A Jedi]

Gotcha thanks!

 

[A Jedi]

Hello, forgive the noob question but when choosing a transformer that's rated at 230v, do I simply multiply the secondary voltage by 1.92 for 120v? So for an F5, I'd need secondaries at ~35v correct?

 

[6L6]

Have a link to that transformer?

 

[A Jedi]

Have a link to that transformer?

I would be using two of these:

TTS0200 - Transformer TS200VA/230 - voltage to 50 V - Shop Toroidy.pl

 

[A Jedi]

All of Toroidy's trafos are rated at 230v from what I can tell.

 

[6L6]

You want to use those transformers with 120VAC mains?

Have you already ordered them or already have them on hand? They make transformers with 120V primaries…

 

[A Jedi]

Yup I'm in the US so 120vac. I haven't ordered yet. I didn't see any on their site or on the item dropdown options. Am I blind? Or is it a custom order via email?

 

[starcat]

Toroidy actually make those with two 115V primaries as well, just ask or select the two primaries config. Wire in parallel and use in the US. Lots of guys out on head-case are using those with their headphone amps in the US.

Toroidy is located in Poland, EU.