Need help with a power adapter for a Jecklin Transdyn 2

[Kei]

For years I have owned this apparently very rare Jecklin Transdyn 2, that I got together with some other old gear. However, I don’t have an AC-AC adapter for it, so I have never been able to check if it even works.

I know/understand very little about electronics, so I need some help: what do I actually need to buy to get this powered up?

These are the specs from the manual:

So, 220 Volt AC (I live in Sweden, so no problem) to ”2 x 15v” AC, whatever that means… It uses this 3 pins DIN connector, where the orange wire and one of the black ones goes to the power switch -> the fuses -> what I assume is a full bridge rectifier:



I guess the DIN connector could be replaced with some other connector if that would make things easier. Any help here to get this running would be much appreciated!

 

[Sokel]

Any transformer with 2x15VAC secondaries will do,either a ready one or a toroidal that you can put in a box.
You'll need one with center tap,just cut the old connector and connect it straight to it.

 

[Count Arthur]

Any of these should do the trick: https://uk.farnell.com/c/transforme...?secondary-voltages=2-x-15v&power-rating=30va

And one of these: https://uk.farnell.com/multicomp-pro/ps000052/din-audio-video-conn-plug-3pos/dp/2787092

Obviously you'll need to put it in a box, with a mains connector and a cable for the connector. Could be a fun little project.

 

[Kei]

Thanks for the replies!

So basically build something like this? https://iwistao.com/products/iwista...mer-15w-audio-dedicated-whole-aluminum-casing

What would I do with the third pin/wire, that in my case ends up going through (what I think is) a high resistance resistor and then to ground/the chassi?

 

[Count Arthur]

I don't think that will work.

I can't be sure, and I'm not I'm not an electronics expert, just a hobbyist, but given that the Jecklyn uses a three pin power connector, I suspect it is connected something like this:

Where the 2 black and the orange wires on the right correspond to those on the 3 pin connector.

 

[Kei]

Since one of the black wires and the orange wires both go to the power switch and then to the fuses, shouldn’t that be 15 V och each of those two, with the second black wire for 0 V?

 

[Kei]

The rectifier from both sides, one flipped so things line up.

 

[Kei]

And an ugly drawing of the components seen from underneath along the traces:

Does all this then mean that 15+15=30 V DC will be going out on the red wire?

 

[Count Arthur]

Yes, I think this is a very basic, dual rail power supply, along these lines:

In your image above, pin 1 and pin 3 are 15v AC, and pin 2 is the 0v centre tap.

It's odd that they chose to use 2 black and one orange wire, rather than 3 different colours, or choose the orange for 0v, as it's the odd one out.

In any case, as long a you connect pin 2 to the centre tap of the transformer, or the combined 0v wires of a transformer with dual secondaries, it doesn't really matter which way round you connect the other 2.

 

[Kei]

I showed my latest image to ChatGPT, and I’m amazed that it understood the whole thing:

 

[Kei]

Yes, I think this is a very basic, dual rail power supply, along these lines:

View attachment 418373
In your image above, pin 1 and pin 3 are 15v AC, and pin 2 is the 0v centre tap.

It's odd that they chose to use 2 black and one orange wire, rather than 3 different colours, or choose the orange for 0v, as it's the odd one out.

In any case, as long a you connect pin 2 to the centre tap of the transformer, or the combined 0v wires of a transformer with dual secondaries, it doesn't really matter which way round you connect the other 2.

So if I would get something like this: https://www.farnell.com/datasheets/3170001.pdf

Then I would connect Red to Pin 1, Yellow to Pin 3 and join Black and Orange (or just one of them?) to Pin 2, correct?

 

[Count Arthur]

Then I would connect Red to Pin 1, Yellow to Pin 3 and join Black and Orange (or just one of them?) to Pin 2, correct?

Yes, connect the black and orange wires to effectively create a 0v centre tap, and connect that to pin 2.

The red and yellow wires go to pins 1 and 3. It doesn't matter which goes where, as it's AC.

If you use a metal box, I would use a 3 pin mains inlet and connect the case to earth: https://uk.farnell.com/schurter/6100-3200/inlet-iec-c14-6100-10a/dp/2080464

You can get versions with a fuse and a switch. Fused might not be a bad idea, as I don't think you have a fuse in the mains plug, as we do in the UK:

If you use a plastic box, you could use a 2 pin inlet: https://uk.farnell.com/schurter/6160-0021/inlet-iec-c8-2576-2-5a/dp/2080474

A length of 3A, 3 core mains flex will work for the cable to the 3 pole connector: https://uk.farnell.com/multicomp-pro/ps000052/din-audio-video-conn-plug-3pos/dp/2787092

I'd use a terminal block to connect the 3 wires of the mains flex to the secondary wires of the transformer. You could then just twist together the 2 x 0v transformer wires and fit them in one side of the block: https://uk.farnell.com/hellermanntyton/cs5ntpe/terminal-strip-connector-natural/dp/4166059

I'd use a cable gland, which will grip the cable to the 3 pole connector and prevent it being accidentally pulled out of the terminal block: https://uk.farnell.com/pro-power/pg-11-black/pg11-cable-gland-black/dp/3498412

 

[Kei]

Thank you so much for the links and explanation!

 

[Count Arthur]

If you build it, post some pictures and let us know if it works.

If it bursts into flames, post pictures of that too.

 

[Kei]

Haha, will do!

Since I would need some kind of enclosure too, I think I might actually buy this one that I linked above:

And then replace the trafo and PCB with these (but the 50053K, which is 2x15v) and connect an outgoing cable with a 3 pin DIN instead of a socket:

This actually feels doable.