e-licktronic Forum

Couldn't have done this without the very generous help of Jeroenbvo.

This is what I did with the fantastic help from Jeroenbvo

This thread helped me alot and so did http://imgur.com/a/IeBch#4











This is the NAVA PSU Circuit but you can adapt it to the yocto.



Using this from Mouser http://au.mouser.com/Search/ProductDeta ... -VPT30-830
Primary
1) Connect Gray and Violet to each other and insulate the joint. You don't need it further on.
2) Blue and Brown will go to your 115 V/230V input. It doesn't matter here which one goes where. Connect Blue to Blue (Neutral) and Brown (Live) to Brown. You'll want to put your power switch on the Brown line.

Secondary
This one you want in series as well, so you connect;
1) Red to Orange, and this joint is now your 0V center tap which will be connected to the sleeve of where your wall adapter was
2) Black for example goes to the center of where your adapter was.
3) Then Yellow will go to the center of your two added 1N4004's. (Add 2 x 1N4004 and twist them together.
Solder the anode of one to the anode of D2 - Yocto/D110 - NAVA and the cathode of the other to the cathode of D1 - Yocto/D109 - NAVA
This way you change the PSU into a full wave bridge.



Earth from 230V side goes straight to chassis. And that point is also where you hook up one side of the ground loop breaker.




Ground Loop Breaker
2 x 1N54xxx
1 x 10 Ohm 5 Watt
1 x 100nF for filtering RF noise

Test Tip: Just wire the transformer up out of the case and not connected to the Yocto. Insulate all 240V connections. Plug it in and with a multimeter (Set for AC) measure between Red/Orange and Black, you should have more or less 15V AC. Measure between Red/Orange and Yellow and again you will have more or less 15V AC.

Then connect the IO board to the transformer and do your tests on the main wires you connect to the main board like you did for the PSU build in the build guide.

It's not that hard really when you know what windings go where on your Transformer...

If you have the information share it

Looking good hofmann25!
Glad it worked out for you!

Cheers, Jeroen

jeroenbvo wrote:Looking good hofmann25!
Glad it worked out for you!

Cheers, Jeroen

Cheers man, couldn't have done it without you.

Will this Transistor burn through this live 240v wire?

Normally not, but if you can, maybe try to route the cable behind the electrolytic capacitor on the picture to the right?

jeroenbvo wrote: maybe try to route the cable behind the electrolytic capacitor on the picture to the right?

Good call.

What I did was keep all my transformer wires As Short As Possible but I may have goone too short for testing and keeping it out of the way of that transistor. I tried to find one of the heat sinks from my Nava kit (Same as we got in the yocto) but I couldnt find one...

Cheers man

just getting round to finishing up my yocto, and I want to add a transformer to get rid of the ugly wall wart.

I am wondering how you guys attached the transformer to the case though. I have the metal one by kacper, and I am a bit weary of drilling a hole into it before being entirely sure. The same with grounding to the case, am I just going to have to drill some holes into this lovely case?

Just a hole to attach the transformer coil.

jeroenbvo wrote:Secondary

This one you want in series as well, so you connect;
1) Red to Orange, and this joint is now your 0V center tap which will be connected to the point between C90 and C91
2) Black for example goes to D109
3) Then Yellow will go to the center of your two added 1N4004's.

1) * The point between C90 and C91 is the ground plane no? Where do you solder 0v?
2) * D109/110/111 are all connected yeah? Where does Black go then?
3) Do you connect Yellow to the other side (The side that D109/110/111 are NOT connected) of 2 of the D109 & D110?
4) Ground Loop Breaker to GND on J8?

Do you have photos of this jeroenbvo? Or directions?

OR is this correct?



Thanks jeroenbvo!

Hello Hoffman25,
I have just confirmed your diagram and it works. I put Cathode to diode 109 and the Anode to diode 110 from the twisted pair of diodes then the 15v from the transformer to the twisted end, your other wire connections are also correct. Works a treat I'm very happy. Thanks to Jeroenbvo and to yourself. It has made my life easier.
Cheers.

By the way my connections are done on the solder side of the board like in your pics.