|
Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
|
Thread Tools |
24th Jun 2021, 7:32 am | #1 |
Heptode
Join Date: Oct 2009
Location: Melbourne Australia
Posts: 898
|
Unknown output transformer in early Williamson amp
Anyone identify the maker of the output transformer in the photos from an early Williamson amp? The photo of the amp chassis shows the OPT as the plain boxed transformer on the LHS (not the taller sculptured PT on the RHS). The terminal plate shows the expected terminal markings, and also appears to show ? OHM and ??CS. There were a few output transformer manufacturers advertising in WW, but the photos don't identify the manufacturer.
By exclusion it isn't a Partridge, Woden WOT25, Gilson WO1796, or Gardeners OP736. I don't have any photos of the Elstone MR/W, Savage or Vortexion to compare, and I guess there were a few other UK makers at the time. Ciao, Tim |
24th Jun 2021, 7:44 am | #2 |
Banned
Join Date: Jun 2015
Location: Mareeba, North Queensland, Australia
Posts: 2,704
|
Re: Unknown output transformer in early Williamson amp
I may be wrong, BUT it could be one of the "select" transformers made in Australia. I had a 6BQ5 push pull amp with identical (if very much smaller) made by I believe Ferguson. It was totally potted inside the box. The bottom of the box was likewise soldered into the "case" which was I think tinplate. The nastiest thing about it was that the mounting screws were Aussie made Whitworth, non plated steel screws.
The amp I am speaking of was a Radio, Television and Hobbies version of the GEC amplifier in the back pages of the English textbook, I "think" called the Radio Engineer's Handbook. 6BK8 input, 12AX7 phase splitter, and a couple of 6BQ5's as output. It's just that the construction of that transformer in your pic is identical. Just my observation. Joe |
24th Jun 2021, 9:07 am | #3 |
Dekatron
Join Date: Sep 2007
Location: Oxfordshire, UK.
Posts: 4,310
|
Re: Unknown output transformer in early Williamson amp
The terminals look like wires trapped under screws and the labelling is done slightly wonkily with a set of hand number-punches. I wonder if it's home-wound ? The original Williamson article included the exact winding details to allow readers to do precisely that.
Cheers, GJ
__________________
http://www.ampregen.com |
24th Jun 2021, 12:57 pm | #4 |
Heptode
Join Date: Oct 2009
Location: Melbourne Australia
Posts: 898
|
Re: Unknown output transformer in early Williamson amp
Joe, the amp is presently for sale in the UK and all the parts appear to be of english origin.
Both transformers may not have been original (certainly the PT looks like it has been replaced), and the construction looks a bit like a kit or DIY from parts and a chassis that has been modified to suit. The amp does look like it could be late 1940's. It would have been a keen DIYer to prepare that terminal plate, but yes GJ it looks too unprofessional to have been made by a larger maker. It's a bit uncommon to see such an output transformer. Last edited by Cobaltblue; 24th Jun 2021 at 1:31 pm. Reason: Rules C2 and 3 |