UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players

Notices

Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

Reply
 
Thread Tools
Old 28th Oct 2020, 7:42 pm   #61
cdm1christopher
Heptode
 
cdm1christopher's Avatar
 
Join Date: Apr 2019
Location: Birchington, Kent, UK.
Posts: 656
Default Re: Vortexion reel to reel tape recorder WVA series 5

Is it a shockley diode
cdm1christopher is offline   Reply With Quote
Old 28th Oct 2020, 8:07 pm   #62
cdm1christopher
Heptode
 
cdm1christopher's Avatar
 
Join Date: Apr 2019
Location: Birchington, Kent, UK.
Posts: 656
Default Re: Vortexion reel to reel tape recorder WVA series 5

Em interesting so thyroristor. So it's either on or off no inbetween. So not enough current no latching. So in effect you need to force an increase in current to get it to latch. Plus having a snubber network resistor capacitor. So in effect it seems I've increased the current hence caused it to latch ie open so there obviously was not enough current going through it. I know it's a bit more complicated than that but interesting. So it's not your typical bridge rectifier at all. Or even a normal type of diode.
W V B is different gz30 I have the ez81. Plus 32uf cap not 8uf. So that resistor I changed linked to the valve rectifier depending on switch mode as well as heaters. Em.
Good check tomorrow.
cdm1christopher is offline   Reply With Quote
Old 28th Oct 2020, 8:14 pm   #63
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 9,712
Default Re: Vortexion reel to reel tape recorder WVA series 5

I've lost the plot now.

Lawrence.
ms660 is offline   Reply With Quote
Old 29th Oct 2020, 12:21 pm   #64
DMcMahon
Nonode
 
DMcMahon's Avatar
 
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 2,373
Default Re: Vortexion reel to reel tape recorder WVA series 5

Hope I have not confused the issue by suggesting that the bridge rectifier may be at fault.

It was just another area to check out in terms of the bias measurement/set-up, if the bias generation circuitry checked out OK.

David
DMcMahon is offline   Reply With Quote
Old 29th Oct 2020, 12:58 pm   #65
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 9,712
Default Re: Vortexion reel to reel tape recorder WVA series 5

The bridge rectifier/meter circuit would have been the first thing I would have checked.

Lawrence.
ms660 is offline   Reply With Quote
Old 29th Oct 2020, 6:00 pm   #66
barrymagrec
Heptode
 
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 947
Default Re: Vortexion reel to reel tape recorder WVA series 5

Quote:
Originally Posted by cdm1christopher View Post
Anyone know the exact spec of this diode like I say I've never seen one before its obviously a bridge vf rectifier so low voltage but as usual not having the correct schematic or parts list don't help.
Cheers Chris
It`s a Westinghouse copper oxide rectifier bridge designed specifically as a meter rectifier. They were common in the fifties and sixties, probably before that - I`m fairly sure they are used in some AVOs

If you need to replace it in this application probably a bridge made from any small signal diode would do, germanium or schottky types would be best.
barrymagrec is offline   Reply With Quote
Reply

Thread Tools



All times are GMT. The time now is 6:38 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Copyright ©2002 - 2020, Paul Stenning.