Ekco A144 valve holder replacement - UK Vintage Radio Repair and Restoration Discussion Forum

Martin Bush · 5th May 2015, 7:09 am

Hi all

Yesterday was a day of triumph and tragedy.

The triumph was getting my Ekco A144 powered up and running.

The tragedy was, having spotted a frayed wire going to a pin of one of the valve holders, the pin then disintegrated when I tried to clean the remnants of old wire off.

My question is, how do I replace the valve holder? It looks to be riveted in which immediately presents me with problems and the replacement I found online doesn't look to be the same shape (it doesn't have the two 'wings' either side for riveting).

Martin

Nickthedentist · 5th May 2015, 7:25 am

Martin,

You can sometimes repair the valveholder, by taking an unused contact from one of the other valveholders and fitting it in place of the damaged one.

Nick.

Martin Bush · 5th May 2015, 7:45 am

interesting. Is that an easy procedure?

Nickthedentist · 5th May 2015, 7:49 am

Sometimes it can be.

It also depends on whether you have any unused contacts to steal!

Do post some good pictures so we can see what type of valveholders are used.

N.

Martin Bush · 5th May 2015, 7:57 am

I think it is a B8A. It's certainly a Rimlock type. I only have pictures from below and I'm at work but will try this evening.

HamishBoxer · 5th May 2015, 8:28 am

There is normally an unused pin.A bit of care will transplant it.

Martin Bush · 5th May 2015, 8:31 am

I will take a look. I think my enthusiastic efforts to clean the pin up didn't help in the end. Although when the pin came out it didn't look the right shape - maybe it was damaged when the set was assembled and I just helped it along.

Martin Bush · 5th May 2015, 10:32 am

I've tried to attach a couple of picture, although I don't think they will be too helpful. I will take some from above the chassis tonight.

The ones attached homefully show the frayed wire and then the holder minus the pin.

hansomcommon · 5th May 2015, 10:50 am

By the look of the photo there is still enough of the pin to solder a fresh wire on to, then normal service resumed.

paulsherwin · 5th May 2015, 10:56 am

You are welcome to an ex equipment B8A valveholder FOC if the worst comes to the worst. Send me a PM if you need it.

Martin Bush · 5th May 2015, 11:02 am

Thanks for the kind offer Paul. I will see how I get on and may be in touch.

Martin Bush · 5th May 2015, 11:18 am

Quote:

Originally Posted by hansomcommon

By the look of the photo there is still enough of the pin to solder a fresh wire on to, then normal service resumed.

I think what is left is inside the holder itself. One photo shows the pin pre and the other post disaster...

Herald1360 · 5th May 2015, 12:12 pm

The rectifier valveholder should have a few unused pins. Careful straightening should allow one to be pushed out and refitted where needed. Probably best not to try rebending it once in position, the solder blob on the joint will stop it from coming out again.

G6Tanuki · 5th May 2015, 6:21 pm

You may be able to repurpose a pin from another valve-socket, but if it's one of the stamped-brass-fork type by McMurdo these seem to suffer from a strange embrittlement [probably due to the load of the valve-pins] which causes one leg of the fork to go crystalline and then snap off at the base.

Other brands seem less susceptible - presumably a different brass alloy, or maybe they more-optimally radiused the stress-concentrator at the base of the fork?

Martin Bush · 5th May 2015, 7:07 pm

It looks like I owe you chaps a pint...

I was in the workshop taking some pictures to show you the damage from both sides and I spotted some spare pins. I fiddled a bit and managed to move one over.

One minor bungle later involving a wire and the set works again. So now I am back where I was this time yesterday, but with some useful knowledge.

Thanks again...

Orthicon · 5th May 2015, 7:08 pm

Martin,
I had a similar problem where the valve sockets had gone very brittle on a A144 I was restoring.
Just us a hand drill to drill out the 2 rivets that attach the valve holder to the chassis.
You wont even have to drill all the way through, as soon as the rivet head is gone, the rest of the rivet should then be easily removed. Then it's a relatively easy job of installing a new valve holder (B8A) and rewiring it. New Valve holders are still obtainable, but make sure the repacement one is ceramic as they are much more robust.

Ian.

Martin Bush · 5th May 2015, 7:12 pm

Hi Ian

I have a hand drill, which now looks like a good buy...

And you have answered the question I was still keen to know the answer too as I am sure I will have another mishap.

When fitting the new holder do you need to rivet again or will nuts and bolts with washers suffice?

Martin

paulsherwin · 5th May 2015, 7:32 pm

Nuts and bolts are fine unless the cosmetic appearance is unusually important.

It is worth buying a Dremel style tool if you plan to work on old radios. A cheap copy will be fine for occasional use. An electric screwdriver with a snap in chuck is also useful at times.

5th May 2015, 7:09 am	#1
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Ekco A144 valve holder replacement Hi all Yesterday was a day of triumph and tragedy. The triumph was getting my Ekco A144 powered up and running. The tragedy was, having spotted a frayed wire going to a pin of one of the valve holders, the pin then disintegrated when I tried to clean the remnants of old wire off. My question is, how do I replace the valve holder? It looks to be riveted in which immediately presents me with problems and the replacement I found online doesn't look to be the same shape (it doesn't have the two 'wings' either side for riveting). Martin

5th May 2015, 7:25 am	#2
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,846	Re: Ekco A144 valve holder replacement Martin, You can sometimes repair the valveholder, by taking an unused contact from one of the other valveholders and fitting it in place of the damaged one. Nick.

5th May 2015, 7:45 am	#3
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement interesting. Is that an easy procedure?

5th May 2015, 7:49 am	#4
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,846	Re: Ekco A144 valve holder replacement Sometimes it can be. It also depends on whether you have any unused contacts to steal! Do post some good pictures so we can see what type of valveholders are used. N.

5th May 2015, 7:57 am	#5
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement I think it is a B8A. It's certainly a Rimlock type. I only have pictures from below and I'm at work but will try this evening.

5th May 2015, 8:28 am	#6
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Ekco A144 valve holder replacement There is normally an unused pin.A bit of care will transplant it. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

5th May 2015, 8:31 am	#7
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement I will take a look. I think my enthusiastic efforts to clean the pin up didn't help in the end. Although when the pin came out it didn't look the right shape - maybe it was damaged when the set was assembled and I just helped it along.

5th May 2015, 10:32 am	#8
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement I've tried to attach a couple of picture, although I don't think they will be too helpful. I will take some from above the chassis tonight. The ones attached homefully show the frayed wire and then the holder minus the pin. Attached Thumbnails

5th May 2015, 10:50 am	#9
hansomcommon Pentode Join Date: Jan 2014 Location: Alton, Hampshire, UK. Posts: 170	Re: Ekco A144 valve holder replacement By the look of the photo there is still enough of the pin to solder a fresh wire on to, then normal service resumed.

5th May 2015, 10:56 am	#10
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Ekco A144 valve holder replacement You are welcome to an ex equipment B8A valveholder FOC if the worst comes to the worst. Send me a PM if you need it.

5th May 2015, 11:02 am	#11
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement Thanks for the kind offer Paul. I will see how I get on and may be in touch.

5th May 2015, 12:12 pm	#13
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Ekco A144 valve holder replacement The rectifier valveholder should have a few unused pins. Careful straightening should allow one to be pushed out and refitted where needed. Probably best not to try rebending it once in position, the solder blob on the joint will stop it from coming out again. __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

5th May 2015, 6:21 pm	#14
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: Ekco A144 valve holder replacement You may be able to repurpose a pin from another valve-socket, but if it's one of the stamped-brass-fork type by McMurdo these seem to suffer from a strange embrittlement [probably due to the load of the valve-pins] which causes one leg of the fork to go crystalline and then snap off at the base. Other brands seem less susceptible - presumably a different brass alloy, or maybe they more-optimally radiused the stress-concentrator at the base of the fork?

5th May 2015, 7:07 pm	#15
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement It looks like I owe you chaps a pint... I was in the workshop taking some pictures to show you the damage from both sides and I spotted some spare pins. I fiddled a bit and managed to move one over. One minor bungle later involving a wire and the set works again. So now I am back where I was this time yesterday, but with some useful knowledge. Thanks again...

5th May 2015, 7:08 pm	#16
Orthicon Retired Dormant Member Join Date: Aug 2011 Location: Cambridge, UK. Posts: 97	Re: Ekco A144 valve holder replacement Martin, I had a similar problem where the valve sockets had gone very brittle on a A144 I was restoring. Just us a hand drill to drill out the 2 rivets that attach the valve holder to the chassis. You wont even have to drill all the way through, as soon as the rivet head is gone, the rest of the rivet should then be easily removed. Then it's a relatively easy job of installing a new valve holder (B8A) and rewiring it. New Valve holders are still obtainable, but make sure the repacement one is ceramic as they are much more robust. Ian.

5th May 2015, 7:12 pm	#17
Martin Bush Octode Join Date: Jan 2015 Location: Oxfordshire, UK. Posts: 1,910	Re: Ekco A144 valve holder replacement Hi Ian I have a hand drill, which now looks like a good buy... And you have answered the question I was still keen to know the answer too as I am sure I will have another mishap. When fitting the new holder do you need to rivet again or will nuts and bolts with washers suffice? Martin Last edited by Martin Bush; 5th May 2015 at 7:14 pm. Reason: badly phrased

5th May 2015, 7:32 pm	#18
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Ekco A144 valve holder replacement Nuts and bolts are fine unless the cosmetic appearance is unusually important. It is worth buying a Dremel style tool if you plan to work on old radios. A cheap copy will be fine for occasional use. An electric screwdriver with a snap in chuck is also useful at times.