What are these components - UK Vintage Radio Repair and Restoration Discussion Forum

Neil Purling · 17th Jun 2009, 9:04 am

I wonder what the components labelled 'X' are. They look like waxies, and I hope they aren't. There are two around what I assume is the oscillator coil of a superhet.
I am wondering if they are causing a problem (not to be discussed here of course).
I am solely concerned about these components.

Station X · 17th Jun 2009, 9:21 am

I think you'll find they're low value capacitors coated in wax. Under the wax they're probably shaped like two cones stacked base to base. They won't have a paper dielectric though, so should be fine.

MichaelR · 17th Jun 2009, 9:31 am

They look like the mustard coloured mullard capacitors popular in the sixties

Mike

Station X · 17th Jun 2009, 9:42 am

Possible, but I've never seen a Mullard mustard coated in wax.

Skywave · 17th Jun 2009, 12:35 pm

Could they be small coils or RF chokes? A quick test to measure their resistance will answer that Q.

Al. / Skywave

MichaelR · 17th Jun 2009, 12:39 pm

Quote:

Originally Posted by Station X

Possible, but I've never seen a Mullard mustard coated in wax.

He has not confirmed they are coated in wax , he said they looked as though they were.

I have seen the Mullards sometimes with a clear plastic sheath over them and in older well used sets they look as though they have "sweated"

Mike

paulsherwin · 17th Jun 2009, 1:58 pm

I think they look like chokes too.

Paul

evingar · 17th Jun 2009, 9:00 pm

I'd go with Paul - the tapered ends look "chokey" to me

davidw · 18th Jun 2009, 7:42 am

What set is it? A quick look at the schematic would confirm, but I go with chokes.

Neil Purling · 18th Jun 2009, 10:48 am

I have no schematic that specifically relates to this radio, that's one of the problems with these kit radios in the absence of any original data.
I think that the unknown components are capacitors, type unknown. As for the value....
Maybe in the order of 100pf or so. Not sure.

Skywave · 18th Jun 2009, 11:47 am

Neil - have you measured their resistance - as in Post #5?

Al. / Skywave

Mr Moose · 18th Jun 2009, 12:24 pm

Hello,
Look at:-
http://cgi.ebay.co.uk/eBayISAP.dll?V...m=120215329704
Yours, Richard

Skywave · 18th Jun 2009, 12:27 pm

Well done, Richard!

They look identical!

Al. / Skywave

Neil Purling · 18th Jun 2009, 12:36 pm

They are identical. No idea of what sort of capacitor though. It is the fact that they are waxed that concerns me a little. I would have expected a wafer-thin mica capacitor to be honest, for the sake of stability. What types of capacitor construction was around for RF use just about at the end of the 'forties?

Skywave · 18th Jun 2009, 12:52 pm

O.K. - they're capacitors!

Almost certainly, they will be mica. I have since discovered an assortment of caps. the same as these in my 'junk box' - but without the wax. The wax is simply there to seal the ends where the lead-out wires are connected. Rather than just add wax to the ends of the tube containing the capacitor, it was far easier to dunk the whole issue in hot wax, especially since using wax to seal low-uF caps. during this time was de rigeur.

It is unlikely that they are faulty or will become so for quite a few years yet (if at all) - but a quick check with an ohm-meter (resistance) now won't go amiss.

Al. / Skywave.

Oldtimer74 · 2nd Jul 2009, 12:26 am

I think they may be early ceramic capacitors somewhere in the 0-100pF range.

PatG3IKR

17th Jun 2009, 9:04 am	#1
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,085	What are these components I wonder what the components labelled 'X' are. They look like waxies, and I hope they aren't. There are two around what I assume is the oscillator coil of a superhet. I am wondering if they are causing a problem (not to be discussed here of course). I am solely concerned about these components. Attached Thumbnails

17th Jun 2009, 9:21 am	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,286	Re: What are these components I think you'll find they're low value capacitors coated in wax. Under the wax they're probably shaped like two cones stacked base to base. They won't have a paper dielectric though, so should be fine. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

17th Jun 2009, 9:31 am	#3
MichaelR Retired Dormant Member Join Date: Mar 2006 Location: Sheffield, South Yorkshire, UK. Posts: 1,587	Re: What are these components They look like the mustard coloured mullard capacitors popular in the sixties Mike

17th Jun 2009, 9:42 am	#4
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,286	Re: What are these components Possible, but I've never seen a Mullard mustard coated in wax. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

17th Jun 2009, 1:58 pm	#7
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,932	Re: What are these components I think they look like chokes too. Paul

17th Jun 2009, 12:35 pm	#5
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: What are these components Could they be small coils or RF chokes? A quick test to measure their resistance will answer that Q. Al. / Skywave

17th Jun 2009, 9:00 pm	#8
evingar Octode Join Date: Oct 2003 Location: Newbury, Berkshire, UK. Posts: 1,770	Re: What are these components I'd go with Paul - the tapered ends look "chokey" to me __________________ Chris

18th Jun 2009, 7:42 am	#9
davidw Heptode Join Date: Sep 2006 Location: Woodbridge, Suffolk, UK. Posts: 643	Re: What are these components What set is it? A quick look at the schematic would confirm, but I go with chokes. __________________ Dave G1AGK. My perception is my reality!

18th Jun 2009, 10:48 am	#10
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,085	Re: What are these components I have no schematic that specifically relates to this radio, that's one of the problems with these kit radios in the absence of any original data. I think that the unknown components are capacitors, type unknown. As for the value.... Maybe in the order of 100pf or so. Not sure.

18th Jun 2009, 11:47 am	#11
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: What are these components Neil - have you measured their resistance - as in Post #5? Al. / Skywave

18th Jun 2009, 12:24 pm	#12
Mr Moose Octode Join Date: Jul 2008 Location: Gloucestershire, UK. Posts: 1,043	Re: What are these components Hello, Look at:- http://cgi.ebay.co.uk/eBayISAP.dll?V...m=120215329704 Yours, Richard

18th Jun 2009, 12:27 pm	#13
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: What are these components Well done, Richard! They look identical! Al. / Skywave

18th Jun 2009, 12:36 pm	#14
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,085	Re: What are these components They are identical. No idea of what sort of capacitor though. It is the fact that they are waxed that concerns me a little. I would have expected a wafer-thin mica capacitor to be honest, for the sake of stability. What types of capacitor construction was around for RF use just about at the end of the 'forties?

18th Jun 2009, 12:52 pm	#15
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: What are these components O.K. - they're capacitors! Almost certainly, they will be mica. I have since discovered an assortment of caps. the same as these in my 'junk box' - but without the wax. The wax is simply there to seal the ends where the lead-out wires are connected. Rather than just add wax to the ends of the tube containing the capacitor, it was far easier to dunk the whole issue in hot wax, especially since using wax to seal low-uF caps. during this time was de rigeur. It is unlikely that they are faulty or will become so for quite a few years yet (if at all) - but a quick check with an ohm-meter (resistance) now won't go amiss. Al. / Skywave.

2nd Jul 2009, 12:26 am	#16
Oldtimer74 Rest in Peace Join Date: Apr 2008 Location: Worcester, Worcestershire, UK. Posts: 330	Re: What are these components I think they may be early ceramic capacitors somewhere in the 0-100pF range. PatG3IKR