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 16th Jan 2018, 7:38 pm   #1
Stockden
Heptode
 
Join Date: Mar 2008
Location: Forest of Dean, Gloucestershire, UK.
Posts: 647
Default What voltage rating are these caps please?

These capacitors were amongst a load of mixed components that I bought recently. I have a couple of physically identical resistors that are helpfully marked " High Voltage Resistor" but these are definitely caps and the only markings are the ones that you can see in the photos.

Does anybody know what rating these things are please?

TIA,
Hugh
Attached Thumbnails
Click image for larger version

Name:	Cap 1.jpg
Views:	214
Size:	90.5 KB
ID:	155574   Click image for larger version

Name:	Cap 2.jpg
Views:	200
Size:	79.5 KB
ID:	155575  
Stockden is offline  
Old 17th Jan 2018, 8:41 am   #2
Boater Sam
Banned
 
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,897
Default Re: What voltage rating are these caps please?

No. But I would be very charry about using them unless you test them very thoroughly, to the extent of destruction testing several to try to establish a working voltage. Even then I would only use them in a very non critical application, like a transistor radio.
NOS and suspect caps are really not the best thing to use, anywhere.
My small stock of acquired NOS caps get checked before use but any that have odd markings or no voltage etc. get binned.
What is the origin of them, they look very odd?
Boater Sam is offline  
Old 17th Jan 2018, 10:46 am   #3
peter_sol
Octode
 
Join Date: Aug 2003
Location: Welwyn Garden City, Herts. UK.
Posts: 1,906
Default Re: What voltage rating are these caps please?

I think they are resistors possibly 5 watts
What makes you think they are caps?
peter_sol is offline  
Old 17th Jan 2018, 11:32 am   #4
Boater Sam
Banned
 
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,897
Default Re: What voltage rating are these caps please?

They do look resistorish. Some are marked JR, some JS. Values 470 & 820

Too flakey to consider?
Boater Sam is offline  
Old 17th Jan 2018, 11:34 am   #5
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: What voltage rating are these caps please?

The OP has nearly 400 posts to his name. I would assume he's checked them with an ohmmeter and found them open circuit, suggesting they're capacitors?
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is online now  
Old 17th Jan 2018, 11:40 am   #6
ms660
Dekatron
 
ms660's Avatar
 
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
Default Re: What voltage rating are these caps please?

What are the capacitance values (by measurement) and the dimensions?

Capacitance value relative to dimensions might give a rough idea.

Lawrence.
ms660 is offline  
Old 17th Jan 2018, 11:40 am   #7
barrymagrec
Octode
 
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
Default Re: What voltage rating are these caps please?

I have vague memories of caps that looked like that from when I was a B.O.T apprentice at Bletchley. I think they must have been fairly old even then (67 / 68) as they were in a load of surplus ministry junk given to us to play about with. I always assumed they were an early ceramic type but I could easily be wrong.
barrymagrec is offline  
Old 17th Jan 2018, 12:31 pm   #8
turretslug
Dekatron
 
turretslug's Avatar
 
Join Date: Nov 2011
Location: Surrey, UK.
Posts: 4,385
Default Re: What voltage rating are these caps please?

They look very much like typical examples of the silvered ceramic rod type capacitors that abounded in electronics from about just post-war until at least the '70s, available in a wide range of values from fractional-pf to low tens of nF and a wide range of temperature coefficients- in other words, the sort of duties that disc ceramics subsequently took on. ISTR they were made by Erie (amongst others?) and this would tie in with the outer ceramic body that was also used for their resistors- though the capacitors had a rather better reputation. Anyone who's worked on ex-military kit (in particular) will have seen lots of these- although the labelling is usually bolder and more explicit. One thing that seemed to be elusive with them was the voltage rating, I don't recall seeing this on any. There were different sizes in similar capacitance, though.

If there was a time-warp machine, I'd hoover up as many NOS as I could, classic vintage components.

A typical shot of a typical application in a typical radio....

Late edit- a peek through a few equipment component lists shows many Erie Ceramicons descibed as 500V DC working, a few at 750V DC working-perhaps the bigger ones? Nothing less than 500V, possibly these being "valve era", there wasn't sufficient demand for lower voltage development.
Attached Thumbnails
Click image for larger version

Name:	Ceramic capacitor.jpg
Views:	147
Size:	51.4 KB
ID:	155613  

Last edited by turretslug; 17th Jan 2018 at 12:59 pm. Reason: Supplement.
turretslug is offline  
Old 17th Jan 2018, 1:14 pm   #9
M0FYA Andy
Nonode
 
Join Date: May 2007
Location: Preston, Lancashire, UK.
Posts: 2,510
Default Re: What voltage rating are these caps please?

I agree that they look like Erie Ceramicons - which is why they look like Erie resistors enclosed in a ceramic tube.
M0FYA Andy is offline  
Old 18th Jan 2018, 7:36 am   #10
Diabolical Artificer
Dekatron
 
Diabolical Artificer's Avatar
 
Join Date: Jul 2009
Location: Sleaford, Lincs. UK.
Posts: 7,637
Default Re: What voltage rating are these caps please?

I have come across these, I have one in a junk box somewhere, they are definitely ceramic caps. As I have a ionisation tester out on the bench I'll pop one across it, but 5 - 750v sounds about right as does Turretslugs reasoning.

Andy.
__________________
Curiosity hasn't killed this cat...so far.
Diabolical Artificer is offline  
Old 18th Jan 2018, 12:40 pm   #11
Freya
Octode
 
Freya's Avatar
 
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,987
Default Re: What voltage rating are these caps please?

They are ceramic, there are several low pF in an Ekco televisions of the 1948-49 era.
__________________
Stephen
_________"It`s only an old telly" ___
Freya is offline  
Old 18th Jan 2018, 6:31 pm   #12
Stockden
Heptode
 
Join Date: Mar 2008
Location: Forest of Dean, Gloucestershire, UK.
Posts: 647
Default Re: What voltage rating are these caps please?

Erie Ceramicons - thanks Andy & Turretslug, that's exactly the information I was after in order to find out more.

To those who suggested they were really resistors - I made that mistake to start with too but a quick check with a multimeter (just as Graham suggested I had) showed that they weren't. Trying them on a capacitance meter confirmed that they were indeed caps and the number marked on them is the capacitance in picofarads.

Hugh
Stockden is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 7:35 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 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.