Poor valve pin-to-socket connections. - UK Vintage Radio Repair and Restoration Discussion Forum

kenneth · 12th Apr 2007, 9:55 am

When listening to my KB FB10 the volume occasionally suddenly drops. The volume can be restored by touching (moving) slightly the 6BE6 (osc/mixer) which sits a bit loose in its holder (B7G). As I dont fancy changing the base can anyone suggest how I might get the valve to sit more firmly in its present holder?

BassoonBloke · 12th Apr 2007, 11:03 am

Hi Kenneth,

It is possible to close up the pins that are in the valve base by using a very fine (watch repairers) screwdriver. Push this between the edge of the valve pin hole and the base and ease the connector towards the middle (not easy to explain !!). Be carefull not to bend the connector too far as it may have metal fatigue and break (if you're very unlucky).
If you do this to all the connections on the base, things should be less intermittant and the valve will feel much more secure in the base.
Depending on how good the metal connections are, you may have to change the base (in the long run it may be a better thing to do, but a pain, believe me i know !!).

Good luck,
Alan.

milairuk · 12th Apr 2007, 12:44 pm

Quote:

Originally Posted by BassoonBloke

It is possible to close up the pins that are in the valve base by using a very fine (watch repairers) screwdriver. Push this between the edge of the valve pin hole and the base and ease the connector towards the middle (not easy to explain !!). Be carefull not to bend the connector too far as it may have metal fatigue and break (if you're very unlucky).

Or depending on the base I find a fairly large sewing needle purloined from the wife is very effective as well

John

Hunts smoothing bomb · 12th Apr 2007, 4:12 pm

It's a bit dodgy but in the past I have remedied this problem by very slightly bending the valve pins outward.
I only use this method if:-

1. The pins in the holder look like they will break if I touch them.

2. The valve which I am about to "bodge" isn't rare and is inexpensive to replace.

Lee

BassoonBloke · 12th Apr 2007, 4:25 pm

Hi,

I must admit that i have also tried the valve pin bending solution, but i just hate it when the chunk of glass breaks off of the side of the valve with a crunch, and it's all over for the valve !!

Cheers,
Alan.

Radio Fixer · 12th Apr 2007, 6:06 pm

Try cleaning the valve pins as well as closing the sockets up in the base. Fine emery paper will take a lot of deposit and corrosion off of the pins.

PaulR · 12th Apr 2007, 7:18 pm

I also use the pin bending technique where all else fails. The purists will probably call it a bodge but it works. Just a very little usually does it

Paul

Darren-UK · 12th Apr 2007, 10:33 pm

Me too, the pin bending bodge is also my easy way out. I do this with a fingernail rather than any form of tool and, so far at least, I've never ruined a valve through either a broken pin or glass.

I normally also clean the pins and sockets at the same time, after the bending bodge. I give the sockets a good dose of something like Servisol Aeroklene 50 ( the one which evaporates ) and then push the valve in and out of the socket two or three times. Fluid evaporates, pins+sockets clean and with a decent mechanical contact.........sorted

.

kenneth · 13th Apr 2007, 11:34 am

OK John, Lee, Alan, Radiofixer, Paul and Darren.. Will start with the valve base pins and see how that goes. Thank for the tips.

Ken.

kenneth · 16th Apr 2007, 9:41 am

Just to finish the story off. Yesterday afternoon I got around to putting the advice into practice. Made a suitable tool by straightening out a large safety pin and with this it was fairly staightforward to get behind the holding pins in the valve base and prise them inwards. The valve now sits very snugly indeed. Job done. Thanks al.l

Ken.

Hybrid tellies · 16th Apr 2007, 8:40 pm

I use to have a telly with a valved uhf tuner. The problem was intermittent loss of some of the channels. The cause was a loose valve socket for the PC86 mixer oscillator valve. As you could not get to the valve base you had to carefully bend the valve pins until you got a tight fit and could receive all the local uhf tv channels.
It was a tricky rather delicate job but it ended up as a permanent fix

12th Apr 2007, 9:55 am	#1
kenneth Retired Dormant Member Join Date: Apr 2005 Location: Cheltenham, Gloucestershire, UK. Posts: 173	Poor valve pin-to-socket connections. When listening to my KB FB10 the volume occasionally suddenly drops. The volume can be restored by touching (moving) slightly the 6BE6 (osc/mixer) which sits a bit loose in its holder (B7G). As I dont fancy changing the base can anyone suggest how I might get the valve to sit more firmly in its present holder?

12th Apr 2007, 11:03 am	#2
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Re: Apparent loose valve Hi Kenneth, It is possible to close up the pins that are in the valve base by using a very fine (watch repairers) screwdriver. Push this between the edge of the valve pin hole and the base and ease the connector towards the middle (not easy to explain !!). Be carefull not to bend the connector too far as it may have metal fatigue and break (if you're very unlucky). If you do this to all the connections on the base, things should be less intermittant and the valve will feel much more secure in the base. Depending on how good the metal connections are, you may have to change the base (in the long run it may be a better thing to do, but a pain, believe me i know !!). Good luck, Alan.

12th Apr 2007, 4:12 pm	#4
Hunts smoothing bomb Octode Join Date: Oct 2005 Location: Wimborne, Dorset, UK. Posts: 1,407	Re: Apparent loose valve It's a bit dodgy but in the past I have remedied this problem by very slightly bending the valve pins outward. I only use this method if:- 1. The pins in the holder look like they will break if I touch them. 2. The valve which I am about to "bodge" isn't rare and is inexpensive to replace. Lee __________________ Lee

12th Apr 2007, 4:25 pm	#5
BassoonBloke Pentode Join Date: Feb 2006 Location: East London, UK. Posts: 231	Re: Apparent loose valve Hi, I must admit that i have also tried the valve pin bending solution, but i just hate it when the chunk of glass breaks off of the side of the valve with a crunch, and it's all over for the valve !! Cheers, Alan.

12th Apr 2007, 6:06 pm	#6
Radio Fixer Retired Dormant Member Join Date: Jun 2006 Location: thorpe bay Posts: 25	Re: Apparent loose valve Try cleaning the valve pins as well as closing the sockets up in the base. Fine emery paper will take a lot of deposit and corrosion off of the pins.

12th Apr 2007, 7:18 pm	#7
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,236	Re: Apparent loose valve I also use the pin bending technique where all else fails. The purists will probably call it a bodge but it works. Just a very little usually does it Paul

12th Apr 2007, 10:33 pm	#8
Darren-UK Retired Dormant Member Join Date: Apr 2003 Location: Blackpool, Lancashire, UK. Posts: 4,061	Re: Apparent loose valve Me too, the pin bending bodge is also my easy way out. I do this with a fingernail rather than any form of tool and, so far at least, I've never ruined a valve through either a broken pin or glass. I normally also clean the pins and sockets at the same time, after the bending bodge. I give the sockets a good dose of something like Servisol Aeroklene 50 ( the one which evaporates ) and then push the valve in and out of the socket two or three times. Fluid evaporates, pins+sockets clean and with a decent mechanical contact.........sorted .

13th Apr 2007, 11:34 am	#9
kenneth Retired Dormant Member Join Date: Apr 2005 Location: Cheltenham, Gloucestershire, UK. Posts: 173	Re: Apparent loose valve OK John, Lee, Alan, Radiofixer, Paul and Darren.. Will start with the valve base pins and see how that goes. Thank for the tips. Ken.

16th Apr 2007, 9:41 am	#10
kenneth Retired Dormant Member Join Date: Apr 2005 Location: Cheltenham, Gloucestershire, UK. Posts: 173	Re: Apparent loose valve Just to finish the story off. Yesterday afternoon I got around to putting the advice into practice. Made a suitable tool by straightening out a large safety pin and with this it was fairly staightforward to get behind the holding pins in the valve base and prise them inwards. The valve now sits very snugly indeed. Job done. Thanks al.l Ken. Last edited by kenneth; 16th Apr 2007 at 9:44 am. Reason: spelling

16th Apr 2007, 8:40 pm	#11
Hybrid tellies Nonode Join Date: Jan 2004 Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area. Posts: 2,967	Re: Apparent loose valve I use to have a telly with a valved uhf tuner. The problem was intermittent loss of some of the channels. The cause was a loose valve socket for the PC86 mixer oscillator valve. As you could not get to the valve base you had to carefully bend the valve pins until you got a tight fit and could receive all the local uhf tv channels. It was a tricky rather delicate job but it ended up as a permanent fix __________________ Simon BVWS member