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Output Transformer Help

PostPosted: Sat Feb 21, 2009 12:07 am
by MashBill
I finally received my Jian Shin (James) output transformers from Taiwan. They look very nice. They are described as an improvement on the JS-6123/JS-6011 model. Following are the specifications:
They are rated for 20W (30W max)
3.5k ohm primary with screen winding
Secondaries are 4, 8, and 16 ohms

I'm confused regarding the primary hookup to the GSG with 6B4G output tubes. I think the B+ wire goes to J7 and the Plate wire goes to pin 3 of the 6B4G, but should I do anything with the screen grid wire? Should I just cap it off with a small wire nut and tuck it out of the way?

By the way I had an aluminum top plate made by Front Panel Express and it is beautiful! Tomorrow I'm going to my wood-worker friend's house to make the base. I'll post pics in the next week or so.

Thanks,
Bill

PostPosted: Sat Feb 21, 2009 6:26 am
by WA4SWJ
Bill,

You're correct - just cap it off. It's not needed.

I've built some amps with Front Panel Express panels too and they are indeed beautiful. I must have spent enough money with them because they sent me a chocolate bar in the shape of a panel for Christmas. They do an excellent job.

Good luck with the amp and looking forward to the pictures.

Regards,

PostPosted: Sat Feb 21, 2009 1:46 pm
by snitch56
Bill,
Which vendor and/or website did you go through to order the James OTs?
Thanks,
Brad

PostPosted: Sat Feb 21, 2009 5:47 pm
by Ty_Bower
There was a guy on eBay who had nine pair for sale. They're gone now. Wish I had grabbed a set...

PostPosted: Sat Feb 21, 2009 6:50 pm
by MashBill
Ty is correct. The seller is no longer on ebay. He started out with 15 pair. I bought 2 pair from him. He also had the best octal tube sockets I have ever seen. I bought 4 of those too. He was easy to deal with and had very positive feedback. Maybe he will return sometime in the future.

PostPosted: Sun Feb 22, 2009 12:26 am
by SDS-PAGE
And another two purchases by me...they are a great match for 300Bs too. They physically smaller than the James 6123HS. Those OPTs did come with James stickers.

PostPosted: Thu Feb 26, 2009 11:51 pm
by MashBill
I was mistaken....

Search for "wonderco_buy" on ebay. I don't think he has any transformers listed now, but you could contact him to see if he has any left.

Bill