“Solid-Tube” rectifier replacement - UK Vintage Radio Repair and Restoration Discussion Forum

Phil G4SPZ · 10th Dec 2019, 11:53 pm

I found two of these within a box of mainly used ex-TV valves recently donated. I’ve never seen anything like it before and I thought I’d share it with you!

Phil

Argus25 · 10th Dec 2019, 11:58 pm

Quote:

Originally Posted by Phil G4SPZ

I found two of these within a box of mainly used ex-TV valves recently donated. I’ve never seen anything like it before and I thought I’d share it with you!

Phil

These were moderately popular and quite common in USA made TV's, they are simply a high voltage silicon EHT rectifier to replace the usual valve one. There are some octal versions too that replaced the 1B3.

linescan87 · 11th Dec 2019, 12:12 am

Looks like a EHT rectifier disguised as a valve, haven't seen one of those before. Thanks for sharing.

turretslug · 11th Dec 2019, 12:24 am

Interesting that a US manufacturer should choose to encompass Pro-Electron (i.e. largely European market) coded devices with no mention of equivalent US-type codes- does this mean that there was little European production of this type of device?

joebog1 · 11th Dec 2019, 12:43 am

If I remember rightly, these EHT rectifiers consist of many many tiny discs of selenium arranged in a tube. I "have" somewhere a stripped down version which is a phenolic tube containing the discs. If I can find it, I will post pics.

Joe

Refugee · 11th Dec 2019, 1:45 am

Thorn 1500 triplers used to be tubes of little discs like that.

G6Tanuki · 11th Dec 2019, 9:44 am

I've seen quite a few similar 'solid-state valve-rectifier replacements' - though mainly the versions made by International Rectifier as a substitute for the classic HT rectifiers in amplifiers, receivers etc.

Ed_Dinning · 11th Dec 2019, 10:03 am

The original types were in a phenolic tube and were developed in WW2 by STC I think.
Lots were on the surplus market and used in scopes etc .

I have a couple of the later unis as pictured by the OP, but these were industrial types and on more massive bases

Ed

Phil G4SPZ · 11th Dec 2019, 12:56 pm

Thanks for the info, everyone. I’m donating one of these to the National Valve Museum, and will keep the other just in case!

As far as testing one of these goes, I doubt that a multimeter would apply sufficient forward voltage, but a Megger wouldn’t cause any harm!

Graham G3ZVT · 11th Dec 2019, 5:35 pm

Those would have been handy when the heater winding (half a turn of EHT cable round the LOPTX core) burnt up on an RBM chassis.

I've never seen one before, and like Turretslug I'm intrigued by what's written on the box.

Advert for the home market here. pg45 of the magazine, or pg 47 of the PDF

HERE

they are 12-Pin-Compactron and octal

usradcoll1 · 12th Dec 2019, 2:57 am

It's been ages since I used one. In a few sets the HV rectifier punctured through the insulation, as stated before. I told the customer that it was the cheaper way to go. I carried a few of them with me. both kinds.
Dave, USradcoll 1. I quit servicing 30 years ago, except my own equipment.

Argus25 · 14th Dec 2019, 7:35 am

That was the one, shown on page 47 that I mentioned previously on this thread that replaced the ubiquitous 1B3 and I had seen a number of them before in American sets. They really only became available because of advancements in high voltage silicon rectifiers. They are completely unlike the other type of multi-disc pile high voltage stick seleniums that came a decade or more before them.

There were some American companies that were ahead of the game in the task "replacing valves with semiconductors" .

Other notable examples were Teledyne with the Fetrons that replaced the ECC83 and the 6AK5 and VMI (Voltage multipliers inc) that turned out to make the world's best high voltage silicon rectifiers, extensively used in the Aerospace industry. If you ever see a VMI made rectifier suited/rated to your task, buy it, it will never let you down.

One of the first efforts was obviously to replace the valve HT rectifier, and for example there are also "Silicon 5u4's" Last lime I looked they were still selling these at Surplus Sales in Nebraska. Have a look on this page, just silicon rectifiers potted in a base:

http://www.surplussales.com/Collins/CollAssor.html

Station X · 14th Dec 2019, 11:14 am

Three posts moved to a new thread here:-

https://www.vintage-radio.net/forum/...d.php?t=162164

Maarten · 14th Dec 2019, 3:21 pm

Looks a bit like https://www.vintage-radio.net/forum/...180#post942180 though the brand name is different.

10th Dec 2019, 11:53 pm	#1
Phil G4SPZ Dekatron Join Date: Apr 2005 Location: Bewdley, Worcestershire, UK. Posts: 4,748	“Solid-Tube” rectifier replacement I found two of these within a box of mainly used ex-TV valves recently donated. I’ve never seen anything like it before and I thought I’d share it with you! Phil Attached Thumbnails __________________ Phil Optimist [n]: One who is not in possession of the full facts

11th Dec 2019, 12:12 am	#3
linescan87 Heptode Join Date: Mar 2014 Location: Meath, Ireland Posts: 551	Re: “Solid-Tube” rectifier replacement Looks like a EHT rectifier disguised as a valve, haven't seen one of those before. Thanks for sharing. __________________ All the best, John Joe www.youtube.com/c/ojnojirishvintagetvandradio

11th Dec 2019, 12:24 am	#4
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,394	Re: “Solid-Tube” rectifier replacement Interesting that a US manufacturer should choose to encompass Pro-Electron (i.e. largely European market) coded devices with no mention of equivalent US-type codes- does this mean that there was little European production of this type of device?

11th Dec 2019, 12:43 am	#5
joebog1 Banned Join Date: Jun 2015 Location: Mareeba, North Queensland, Australia Posts: 2,704	Re: “Solid-Tube” rectifier replacement If I remember rightly, these EHT rectifiers consist of many many tiny discs of selenium arranged in a tube. I "have" somewhere a stripped down version which is a phenolic tube containing the discs. If I can find it, I will post pics. Joe

11th Dec 2019, 1:45 am	#6
Refugee Dekatron Join Date: Apr 2012 Location: Worksop, Nottinghamshire, UK. Posts: 5,553	Re: “Solid-Tube” rectifier replacement Thorn 1500 triplers used to be tubes of little discs like that.

11th Dec 2019, 9:44 am	#7
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,996	Re: “Solid-Tube” rectifier replacement I've seen quite a few similar 'solid-state valve-rectifier replacements' - though mainly the versions made by International Rectifier as a substitute for the classic HT rectifiers in amplifiers, receivers etc.

11th Dec 2019, 10:03 am	#8
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: “Solid-Tube” rectifier replacement The original types were in a phenolic tube and were developed in WW2 by STC I think. Lots were on the surplus market and used in scopes etc . I have a couple of the later unis as pictured by the OP, but these were industrial types and on more massive bases Ed

11th Dec 2019, 12:56 pm	#9
Phil G4SPZ Dekatron Join Date: Apr 2005 Location: Bewdley, Worcestershire, UK. Posts: 4,748	Re: “Solid-Tube” rectifier replacement Thanks for the info, everyone. I’m donating one of these to the National Valve Museum, and will keep the other just in case! As far as testing one of these goes, I doubt that a multimeter would apply sufficient forward voltage, but a Megger wouldn’t cause any harm! __________________ Phil Optimist [n]: One who is not in possession of the full facts

11th Dec 2019, 5:35 pm	#10
Graham G3ZVT Dekatron Join Date: May 2010 Location: Greater Manchester, UK. Posts: 18,711	Re: “Solid-Tube” rectifier replacement Those would have been handy when the heater winding (half a turn of EHT cable round the LOPTX core) burnt up on an RBM chassis. I've never seen one before, and like Turretslug I'm intrigued by what's written on the box. Advert for the home market here. pg45 of the magazine, or pg 47 of the PDF HERE they are 12-Pin-Compactron and octal __________________ -- Graham. G3ZVT

12th Dec 2019, 2:57 am	#11
usradcoll1 Heptode Join Date: Mar 2017 Location: Cedar Grove, Wisconsin, USA. Posts: 823	Re: “Solid-Tube” rectifier replacement It's been ages since I used one. In a few sets the HV rectifier punctured through the insulation, as stated before. I told the customer that it was the cheaper way to go. I carried a few of them with me. both kinds. Dave, USradcoll 1. I quit servicing 30 years ago, except my own equipment.

14th Dec 2019, 7:35 am	#12
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: “Solid-Tube” rectifier replacement That was the one, shown on page 47 that I mentioned previously on this thread that replaced the ubiquitous 1B3 and I had seen a number of them before in American sets. They really only became available because of advancements in high voltage silicon rectifiers. They are completely unlike the other type of multi-disc pile high voltage stick seleniums that came a decade or more before them. There were some American companies that were ahead of the game in the task "replacing valves with semiconductors" . Other notable examples were Teledyne with the Fetrons that replaced the ECC83 and the 6AK5 and VMI (Voltage multipliers inc) that turned out to make the world's best high voltage silicon rectifiers, extensively used in the Aerospace industry. If you ever see a VMI made rectifier suited/rated to your task, buy it, it will never let you down. One of the first efforts was obviously to replace the valve HT rectifier, and for example there are also "Silicon 5u4's" Last lime I looked they were still selling these at Surplus Sales in Nebraska. Have a look on this page, just silicon rectifiers potted in a base: http://www.surplussales.com/Collins/CollAssor.html

14th Dec 2019, 11:14 am	#13
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: “Solid-Tube” rectifier replacement Three posts moved to a new thread here:- https://www.vintage-radio.net/forum/...d.php?t=162164 __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

14th Dec 2019, 3:21 pm	#14
Maarten Dekatron Join Date: Dec 2007 Location: Haarlem, Netherlands Posts: 4,199	Re: “Solid-Tube” rectifier replacement Looks a bit like https://www.vintage-radio.net/forum/...180#post942180 though the brand name is different.