[bluesky]

Dear Aksaphiles

Does anyone out there use the Jaycar transformers in their 55 Watt Aksa kits?  The catalogue number of these transformers are MT-2114 and are 160VA 25-0-25 toroids.  I have been having no end of trouble getting the connections right and bothering Hugh when he should be with his family.   I took notes when I bought them and then went back to Jaycar this morning and was advised that I had connected an orange lead incorrectly.

I took the whole amp to the shop and had any number of staff and customers looking over my shoulder, giving advice and marveling at the quality and layout of Hugh's modules.  Needless to say I took the opportunity of telling them that Aksa was big hit around the world and that they should all go out and buy an Aksa for themselves.  Hugh, if you suddenly get a flood of orders from Brisbane you know who to thank.

Anyway, I have connected the transformers as per their advice, I made sure I wrote it down and double checked with two different staff members and an interested customer.  I have connected an orange lead from each transformer to active and neutral, then joined yellow and white together and pink and red together, these then go to each tag on the power supply PCB.  The measurements I get are only 1.3 volts going into the power supply, obviously there's something I have done wrong.  If any of you out  there have used this transformer and can help I would greatly appreciate it.  This is my first venture into kit electronics and I am really having a great time building these amps, Hugh has been quite over the top with his help going way beyond reasonable expectations with his service and I extend my thanks to him.

Cheers, Ian

[Larry]

I have connected an orange lead from each transformer to active and neutral, then joined yellow and white together and pink and red together, these then go to each tag on the power supply PCB

For 160VA and 300VA Jaycar toroids only:

The Pink and Yellow together to the Star Earth; the Red to one AC tag and White to the other AC tag on the power supply PCB.

Make sure you have a fuse on the mains before you try anything with mains.

[Malcolm Fear]

Hi Bluesky
Larry beat me to it. He is correct. I have sent you an email, with a picture of a completed 55 watt.

[bluesky]

Larry and Malcolm

Many thanks!  What amazes me is that the staff at Jaycar were obviously incorrect in their, ahem.... "assistance" to me.  I'll get into the new wiring as soon as I can and look forward to hearing the Aksa in its full glory.  

Ian

[AKSA]

Hey Guys,

Thanks for all the help to Ian.

I suddenly realized what the problem was when I read this:

I have connected an orange lead from each transformer to active and neutral, then joined yellow and white together and pink and red together, these then go to each tag on the power supply PCB.

The orange leads to each transformer to active and neutral is dead right.

Larry and Mal are right, I believe, with Pink and Yellow connected together and placed on Star Earth, and Red to AC1 on the power supply pcb, and White to AC2 on the power supply pcb.

The color scheme for toroidals, and indeed any trafo, is always different, dammit.  There's no standard - none at all.  A shame, causes a lot of angst.  I use the Altronics toroids, which have a very different color sheme with black and white to star earth and different colors to AC1/2.

Ian, I'm sorry I was not able to work it out.  I looked at your email to me and just couldn't figure it out.  Your quote above clarified it.

Thanks again to Larry and Mal who offered great advice, and thanks to Ian for spreading the word about the AKSA!!    

I spent the afternoon sorting out a GK-1M for a Melburnian!  After it was complete we went for breakfast at the local cafe at midday!

Cheers,

Hugh