All-Power Transformers Regulated power supply - UK Vintage Radio Repair and Restoration Discussion Forum

gingpeakin · 26th Jul 2020, 11:34 am

Has anyone any details about this beast? I inherited some years ago.
0 to 500V at 250mA with a seperate 0 to -250V bias and heater supplies. And it works perfectly!
I may be sufficiently bored soon to draw up the circuit.

Ging

26th Jul 2020, 1:23 pm

Any chance of a picture? I just wonder what would need -250V bias!

factory · 26th Jul 2020, 1:39 pm

I don't have any info, but did recognise the PSU as one sold locally very recently, a Model 504;

David

gingpeakin · 26th Jul 2020, 4:16 pm

Apologies - I forgot to press the upload button. It does indeed look like the one pictured - this is a model 505 with 4 807s in parallel for the positive supply and another for the negative.

Diabolical Artificer · 27th Jul 2020, 6:57 am

Nice useful PSU, I'd have a look at those caps though, they'll look well old and tired. What's that pink wire bodge from the tfmr with the wires hanging loose, a LT tap?

Andy.

M0FYA Andy · 27th Jul 2020, 8:30 am

From memory those block capacitors are electrolytics and not paper, so be doubly cautious, I imagine they could fail quite dramatically!

Andy

GrimJosef · 27th Jul 2020, 9:08 am

Those large metal rectifiers look like they could release a good deal of unpleasantness if they should fail too. I have one of these supplies waiting for the ever-absent round tuit. I might well disconnect the rectifiers and hide silicon ones with suitable resistors somewhere nearby.

Cheers,

GJ

Skywave · 27th Jul 2020, 11:05 pm

The under-chassis layout and wiring is simply a work of art.

Al.

26th Jul 2020, 11:34 am	#1
gingpeakin Hexode Join Date: Mar 2009 Location: Worthing, Sussex, UK. Posts: 276	All-Power Transformers Regulated power supply Has anyone any details about this beast? I inherited some years ago. 0 to 500V at 250mA with a seperate 0 to -250V bias and heater supplies. And it works perfectly! I may be sufficiently bored soon to draw up the circuit. Ging

26th Jul 2020, 1:23 pm	#2
Guest Guest Posts: n/a	Re: All-Power Transformers Regulated power supply Any chance of a picture? I just wonder what would need -250V bias!

26th Jul 2020, 1:39 pm	#3
factory Octode Join Date: Jul 2009 Location: Cheshire, UK. Posts: 1,733	Re: All-Power Transformers Regulated power supply I don't have any info, but did recognise the PSU as one sold locally very recently, a Model 504; David Attached Thumbnails

26th Jul 2020, 4:16 pm	#4
gingpeakin Hexode Join Date: Mar 2009 Location: Worthing, Sussex, UK. Posts: 276	Re: All-Power Transformers Regulated power supply Apologies - I forgot to press the upload button. It does indeed look like the one pictured - this is a model 505 with 4 807s in parallel for the positive supply and another for the negative. Attached Thumbnails

27th Jul 2020, 6:57 am	#5
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,662	Re: All-Power Transformers Regulated power supply Nice useful PSU, I'd have a look at those caps though, they'll look well old and tired. What's that pink wire bodge from the tfmr with the wires hanging loose, a LT tap? Andy. __________________ Curiosity hasn't killed this cat...so far.

27th Jul 2020, 8:30 am	#6
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: All-Power Transformers Regulated power supply From memory those block capacitors are electrolytics and not paper, so be doubly cautious, I imagine they could fail quite dramatically! Andy

27th Jul 2020, 9:08 am	#7
GrimJosef Dekatron Join Date: Sep 2007 Location: Oxfordshire, UK. Posts: 4,311	Re: All-Power Transformers Regulated power supply Those large metal rectifiers look like they could release a good deal of unpleasantness if they should fail too. I have one of these supplies waiting for the ever-absent round tuit. I might well disconnect the rectifiers and hide silicon ones with suitable resistors somewhere nearby. Cheers, GJ __________________ http://www.ampregen.com

27th Jul 2020, 11:05 pm	#8
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: All-Power Transformers Regulated power supply The under-chassis layout and wiring is simply a work of art. Al.