EA50 with 2 top connections? - UK Vintage Radio Repair and Restoration Discussion Forum

Ed_Dinning · 8th Apr 2015, 7:24 pm

Hi Gents, a friend has a Lecher line assembly that appears to use 2 identical valves (one for each line) connected to it.
These plug into a B3G (EA50) style base, but there are connections for 2 top connectors; additionally the valve length appears (from the spacing of the parts) to be a bit longer than that of a standard EA50.
Any one any ideas? No references in the Keith Thrower books.

Thanks, Ed

Cobaltblue · 8th Apr 2015, 8:06 pm

EC53 maybe?

Cheers

Mike T

Ed_Dinning · 8th Apr 2015, 8:32 pm

Hi Mike, thanks for that, its not a valve I'd seen before and as there was not one fitted I had no idea what it could be,

Ed

Jeremy M0RVB · 8th Apr 2015, 8:38 pm

NR88 et al - see http://www.tubecollector.org/nr88.htm

Jeremy

Tractorfan · 8th Apr 2015, 9:35 pm

Hi,
I've got one of these kicking around here somewhere. I've often wondered what it was used for.
Cheers, Pete.

Jeremy M0RVB · 8th Apr 2015, 10:16 pm

FYI CV1197 / EC53 does get a brief mention in Keith's 'History of the British Radio Valve to 1940', page 79 - I really must get these books off the shelf more often!

Skywave · 9th Apr 2015, 1:57 am

If you are experimenting with the EC53, a word of caution. The two wires emanating from the top are anode and grid: do not get them connected-up in a cct. the wrong way round! The consequences of doing that will wreck the valve.

Don't ask me how I know that, please : thanks!

Al.

Alan Stepney · 9th Apr 2015, 7:40 am

They work well on 70cm/s.

G6Tanuki · 9th Apr 2015, 7:51 am

I recall seeing one of these used in a WWII-era calibration oscillator allegedly used as part of the Joan/Eleanor portable aircraft beacon test-sets.

Tractorfan · 9th Apr 2015, 8:44 am

Hi.
I imagine that it would be very easy to put it in the holder the wrong way round. Especially if the red mark has chipped off over the years, as I think has happened to mine. I've no immediate plans to use it anyway.
PS. Just a thought. I wonder how it would perform at audio frequencies?
Cheers, Pete.

Herald1360 · 9th Apr 2015, 1:06 pm

Quote:

Originally Posted by Alan Stepney

They work well on 70cm/s.

That's about 1.6mph! Aren't they supposed to be fast valves? OK in a hand held, perhaps......

Ed_Dinning · 11th Apr 2015, 5:56 pm

Hi Gents, I thought this was a piece of university teaching equipment that had been made by the techs, but it could be as you describe G6. Do you have a picture?

Jeremy, I might just see if you have a couple of EC53's tomorrow.

Ed

8th Apr 2015, 7:24 pm	#1
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	EA50 with 2 top connections? Hi Gents, a friend has a Lecher line assembly that appears to use 2 identical valves (one for each line) connected to it. These plug into a B3G (EA50) style base, but there are connections for 2 top connectors; additionally the valve length appears (from the spacing of the parts) to be a bit longer than that of a standard EA50. Any one any ideas? No references in the Keith Thrower books. Thanks, Ed

8th Apr 2015, 8:06 pm	#2
Cobaltblue Moderator Join Date: Dec 2010 Location: Exeter, Devon and Poole, Dorset UK. Posts: 6,866	Re: EA50 with 2 top connections? EC53 maybe? Cheers Mike T Attached Thumbnails __________________ Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk

8th Apr 2015, 8:32 pm	#3
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: EA50 with 2 top connections? Hi Mike, thanks for that, its not a valve I'd seen before and as there was not one fitted I had no idea what it could be, Ed

8th Apr 2015, 8:38 pm	#4
Jeremy M0RVB Hexode Join Date: Jul 2003 Location: Leeds, West Yorkshire, UK. Posts: 458	Re: EA50 with 2 top connections? NR88 et al - see http://www.tubecollector.org/nr88.htm Jeremy

8th Apr 2015, 9:35 pm	#5
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,183	Re: EA50 with 2 top connections? Hi, I've got one of these kicking around here somewhere. I've often wondered what it was used for. Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

8th Apr 2015, 10:16 pm	#6
Jeremy M0RVB Hexode Join Date: Jul 2003 Location: Leeds, West Yorkshire, UK. Posts: 458	Re: EA50 with 2 top connections? FYI CV1197 / EC53 does get a brief mention in Keith's 'History of the British Radio Valve to 1940', page 79 - I really must get these books off the shelf more often!

9th Apr 2015, 1:57 am	#7
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: EA50 with 2 top connections? If you are experimenting with the EC53, a word of caution. The two wires emanating from the top are anode and grid: do not get them connected-up in a cct. the wrong way round! The consequences of doing that will wreck the valve. Don't ask me how I know that, please : thanks! Al.

9th Apr 2015, 7:40 am	#8
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Re: EA50 with 2 top connections? They work well on 70cm/s.

9th Apr 2015, 7:51 am	#9
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: EA50 with 2 top connections? I recall seeing one of these used in a WWII-era calibration oscillator allegedly used as part of the Joan/Eleanor portable aircraft beacon test-sets.

9th Apr 2015, 8:44 am	#10
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,183	Re: EA50 with 2 top connections? Hi. I imagine that it would be very easy to put it in the holder the wrong way round. Especially if the red mark has chipped off over the years, as I think has happened to mine. I've no immediate plans to use it anyway. PS. Just a thought. I wonder how it would perform at audio frequencies? Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

11th Apr 2015, 5:56 pm	#12
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: EA50 with 2 top connections? Hi Gents, I thought this was a piece of university teaching equipment that had been made by the techs, but it could be as you describe G6. Do you have a picture? Jeremy, I might just see if you have a couple of EC53's tomorrow. Ed