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

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Components and Circuits

Notices

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.

Closed Thread
 
Thread Tools
Old 2nd Dec 2021, 8:14 pm   #1
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,951
Default ID this valve.

A power-rectifier, on a 4-pin base with the pins bifurcated, 5V seems to work well as heater voltage.

Indirectly--heated cathodes but with the cathodes strapped to the heaters, which sort-of hints that it is an analog for a directly-heated precursor.

There's a little 'nub' on the bakelite base adjacent to one of the four pins - presumably to give guidance whrn plugging it into its socket.

Intriguingly - the two anode-assemblies are rotationally offset so that they do not face directly towards each-other; this is clearly an attempt to stop them radiating the inevitable anode-dissipation-Watts at each-other.
Attached Thumbnails
Click image for larger version

Name:	base2.JPG
Views:	194
Size:	61.5 KB
ID:	247157   Click image for larger version

Name:	base4.jpg
Views:	193
Size:	40.9 KB
ID:	247158   Click image for larger version

Name:	nub.jpg
Views:	176
Size:	33.2 KB
ID:	247159  
__________________
I'm the Operator of my Pocket Calculator. -Kraftwerk.
G6Tanuki is offline  
Old 2nd Dec 2021, 8:58 pm   #2
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
Default Re: ID this valve.

45-1U:

http://www.r-type.org/exhib/aad0016.htm

?
ms660 is offline  
Old 2nd Dec 2021, 9:58 pm   #3
joebog1
Banned
 
Join Date: Jun 2015
Location: Mareeba, North Queensland, Australia
Posts: 2,704
Default Re: ID this valve.

5U4 with a weird base.

Joe
joebog1 is offline  
Old 3rd Dec 2021, 2:40 pm   #4
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,951
Default Re: ID this valve.

Quote:
Originally Posted by ms660 View Post
I think you're probably right, and that I overdrove the filaments at 5V.

It comes from a push-pull audio amp using a pair of KT66.
__________________
I'm the Operator of my Pocket Calculator. -Kraftwerk.
G6Tanuki is offline  
Old 3rd Dec 2021, 3:39 pm   #5
Techman
Dekatron
 
Techman's Avatar
 
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 4,985
Default Re: ID this valve.

Quote:
Originally Posted by G6Tanuki View Post
There's a little 'nub' on the bakelite base adjacent to one of the four pins
I've mentioned this before regarding these old B4 valves, but there were no comments on it, so I guess nobody knows. My own findings seem to indicate that it's found on very old valves made around 1929 - unless anyone knows any different?
Techman is offline  
Old 3rd Dec 2021, 4:02 pm   #6
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,951
Default Re: ID this valve.

I've never come across a valve with that little nub before. I guess it's to make 'blind' insertion into the base a bit easier by helping you know where oin 1 is.
__________________
I'm the Operator of my Pocket Calculator. -Kraftwerk.
G6Tanuki is offline  
Old 3rd Dec 2021, 4:14 pm   #7
Hartley118
Nonode
 
Hartley118's Avatar
 
Join Date: Aug 2015
Location: Cambridge, Cambs. UK.
Posts: 2,196
Default Re: ID this valve.

Quote:
Originally Posted by ms660 View Post
Cossor valves do tend to become anonymous as they mature because the original ID was often on a stuck-on paper label which is outlasted by the valve itself.

Martin
__________________
BVWS Member
Hartley118 is offline  
Old 3rd Dec 2021, 4:26 pm   #8
Leon Crampin
Octode
 
Join Date: Nov 2005
Location: Surrey, UK.
Posts: 1,869
Default Re: ID this valve.

I have some very early MOV triodes (ML4 etc.) with the same type of base with the locating nub.

Given that this is an indirectly heated rectifier (so not a 5U4) I would suggest that it could be a very early specimen of the MOV type MU12 or MU14.

Leon.
Leon Crampin is online now  
Old 4th Dec 2021, 3:13 pm   #9
Bear2Biker
Triode
 
Bear2Biker's Avatar
 
Join Date: Jan 2011
Location: Bradford, West Yorkshire, UK.
Posts: 43
Default Re: ID this valve.

Yes I've often wondered what the pip was for, I have several 4 & 5 pin valves with this feature, I wondered if it was for the radio servicing chaps, the back of a radio can be very dark to see what your doing, so the pip can easily be used to work out the pin biasing in conjunction with feeling for the screwhead or rivet securing the valve socket in the chassis.

Nearly all 4/5 bases I've come across have the same orientation & if it's wrong first time just rotate 180, no forcing/bent pins.

Many noval valves use that idea, having the widest pin gap facing one of the mounting flanges, of course more difficult on skirted bases but still doable,.
__________________
Bear2Biker
Bear2Biker is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 7:15 pm.


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 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.