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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

BWD 216a power supply circuit needed, please help

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I need a circuit for a BWD 216a power supply, in particular the 400V section.

These were comercially built in Melbourne, Australia in the late 60s early 70s. From this I'm assumimg 95% of you have never even heard of BWD but maybe someone local can help me out.


The tube forum moves very fast so I'm bumping it to the top of the list again hoping someone who can help spots this.
No Australian can resist our traditional cry for help. I'm serious too, I'll phone your local to buy you a jug of your favourite.

The power supply has:
two 6.3V filament supply outputs,
50mA 0-250V
a variable current 200mA 0-400V output.

the 0-400V section is faulty. the getters in the driver tubes for that section look ok, the filaments all light up.
With only one tube plugged in (I tried all four in turn) it doesn't work.
no output at all.

There are a couple of ICs inside, they are very old looking comparators. I swapped them over, assuming one is for 250V and one for 400V, and it still didnt work. At least I know both comparators are ok.
No nothing yet, It's a backburner job at the moment.
Fixing my big ugly Inkel PA amp is the next priority.

Though I was hopeful for a circuit when I saw there was a reply to my thread...

I think BWD supplies were built in australia. I'm getting quite a collection of them with minor faults that people are getting rid of.

I did find somewhere that sold circuits for it, I think about $20-$30. Maybe we can split the cost between us.
BWD Contact

Hi Guys,
BWD still exist and still make test equipment. They are now known as
McVan Instruments. I would guess that they would be happy to assist.

Contact Details:
McVan Instruments Pty Ltd
58 Geddes Street, Mulgrave, VIC, 3170
Phone: (03) 9582 7333, Fax: (03) 9560 1164

They are on the web and have the usual email contact which I won't post here to save them being spammed. Do a websearch.

Thanks Ian. I had heard about McVan but didn't know there was a connection. I'll do a search.
OzMikeH...I have been in touch with a guy who can supply a copy for $34.20. I'm going to try McVan, but if that fizzes, I may go for the copy...and will talk to you about sharing the experience...
Either way, I'll let you know.
BWD216 Power supply manual

Hello, I do have a complete manual for a BWD216A high Voltage supply.
I am happy to scan it and forward it to an email address.
I bought it 8 years ago from Mc Vane Instruments and it cost an arm and a leg. However i will send it at no cost.
I have 3 BWD216A's and they perform well.
I also had one fault in the 400V section. The problem was a short circuited Diode D13 OR D14. They are connected in a 69 configuration.
I replaced the diode wit a 1N4007. This fixed this problem.
I hope this helps.

Regards, Hors
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.