If you had to choose a range of semiconductors... - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Nickthedentist · 11th Sep 2018, 12:53 pm

Anyone remember the "universal" transistor that could be used in any application, that was described in Television magazine about 25 years ago.

It took me a few weeks to realise that it was in the April issue.

Lucien Nunes · 12th Sep 2018, 9:03 pm

I'd add ZTX653/753. 100 / 120V, 2A, 1W, 150MHz, hFE ~200 up to 500mA. E-Line package. I started using them as a pricey but good all rounder in the early '90s and still keep them on hand as problem solvers.

kalee20 · 13th Sep 2018, 9:20 am

Yes the E-line devices were (are?) really good. I used to have ZTX107/ZTX212 as my 'go to' small signal transistors, with ZTX450/550 or ZTX650/750 as higher current; and ZTX600 Darlington.

turretslug · 13th Sep 2018, 9:35 am

I'd forgotten about these gems. A really compact package (if you wanted to cram things in closer than TO92 would allow!) and a wide range of available specs, with some surprisingly high voltage or current options. Folk spoke highly of their dependability. I suspect/fear that the ZTX range would have been another victim of the takeover/closedown/rationalisation syndrome.

Radio Wrangler · 13th Sep 2018, 10:17 am

ZTX transistors were by Ferranti, then spun off as Zetex Ltd, then taken over by Diodes, inc.

Some of their rather nice parts seem to have been rationalised out of exittance, but others continue.

David

Skywave · 13th Sep 2018, 12:18 pm

Transistors that I find I use quite often are BFY90, BFR91A, 2N2905, 2N 2219A, 2N2369A and 2N4416 (N-chan. FET). The MJE340 (previously mentioned) is useful for H.V. circuits, but is complement, the MJE350, seems to be not widely known. Just need to be aware of its lower Ft compared to the '340.

Al.

G6Tanuki · 13th Sep 2018, 7:10 pm

Quote:

Originally Posted by Nickthedentist

Anyone remember the "universal" transistor that could be used in any application, that was described in Television magazine about 25 years ago.

It took me a few weeks to realise that it was in the April issue.

"Elektor" magazine [one of my favourites] had a philosophy of minimising the range of semiconductors used in their designs - so they had their TUP/TUN/DUG/DUS.

TUP: Transistor, Universal, PNP
TUN: Transistor, Universal. NPN
DUG: Diode, Universal, Germanium
DUS: Diode, Universal, Silicon.

I loved this approach: you could build their designs - with a good chance of them working - without the need to order up some specific semiconductors and incurring the then-traditionsl 1970s/1980s week's delay of the supplier waiting for your cheque for £3.25p clearing before they'd post you the parts.

Herald1360 · 13th Sep 2018, 11:18 pm

Quote:

Originally Posted by turretslug

I'd forgotten about these gems. A really compact package (if you wanted to cram things in closer than TO92 would allow!) and a wide range of available specs, with some surprisingly high voltage or current options. Folk spoke highly of their dependability. I suspect/fear that the ZTX range would have been another victim of the takeover/closedown/rationalisation syndrome.

Was that "gem" intentional, by any chance?

https://www.***********/photos/jabrophoto/6925487820

turretslug · 14th Sep 2018, 12:06 am

It wasn't consciously so, though just possibly subliminal! I suppose in terms of being a highly selected morsel of mineral appropriately set, a transistor could be described as a gem though, and a darn useful one at that.

Sad to see a shot like that, I've seen just too much industrial and technological significance turned into rubble over the years.

Radio Wrangler · 14th Sep 2018, 7:08 am

All over the world, there are millions of valves and transistors in use long, long, after the firms and the buildings which produced them are gone.

The product seems to be the only memorial to the producer.

"Gem Mill" was a glorious address to have.

Not far away in Heywood, SEI were making capacitors, ferrites and crystals in "Times Mill"

David

11th Sep 2018, 12:53 pm	#21
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,861	Re: If you had to choose a range of semiconductors... Anyone remember the "universal" transistor that could be used in any application, that was described in Television magazine about 25 years ago. It took me a few weeks to realise that it was in the April issue.

12th Sep 2018, 9:03 pm	#22
Lucien Nunes Rest in Peace Join Date: Apr 2008 Location: London, UK. Posts: 2,508	Re: If you had to choose a range of semiconductors... I'd add ZTX653/753. 100 / 120V, 2A, 1W, 150MHz, hFE ~200 up to 500mA. E-Line package. I started using them as a pricey but good all rounder in the early '90s and still keep them on hand as problem solvers.

13th Sep 2018, 9:20 am	#23
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,087	Re: If you had to choose a range of semiconductors... Yes the E-line devices were (are?) really good. I used to have ZTX107/ZTX212 as my 'go to' small signal transistors, with ZTX450/550 or ZTX650/750 as higher current; and ZTX600 Darlington.

13th Sep 2018, 9:35 am	#24
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,398	Re: If you had to choose a range of semiconductors... I'd forgotten about these gems. A really compact package (if you wanted to cram things in closer than TO92 would allow!) and a wide range of available specs, with some surprisingly high voltage or current options. Folk spoke highly of their dependability. I suspect/fear that the ZTX range would have been another victim of the takeover/closedown/rationalisation syndrome.

13th Sep 2018, 10:17 am	#25
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,901	Re: If you had to choose a range of semiconductors... ZTX transistors were by Ferranti, then spun off as Zetex Ltd, then taken over by Diodes, inc. Some of their rather nice parts seem to have been rationalised out of exittance, but others continue. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

13th Sep 2018, 12:18 pm	#26
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: If you had to choose a range of semiconductors... Transistors that I find I use quite often are BFY90, BFR91A, 2N2905, 2N 2219A, 2N2369A and 2N4416 (N-chan. FET). The MJE340 (previously mentioned) is useful for H.V. circuits, but is complement, the MJE350, seems to be not widely known. Just need to be aware of its lower Ft compared to the '340. Al.

14th Sep 2018, 12:06 am	#29
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,398	Re: If you had to choose a range of semiconductors... It wasn't consciously so, though just possibly subliminal! I suppose in terms of being a highly selected morsel of mineral appropriately set, a transistor could be described as a gem though, and a darn useful one at that. Sad to see a shot like that, I've seen just too much industrial and technological significance turned into rubble over the years.

14th Sep 2018, 7:08 am	#30
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,901	Re: If you had to choose a range of semiconductors... All over the world, there are millions of valves and transistors in use long, long, after the firms and the buildings which produced them are gone. The product seems to be the only memorial to the producer. "Gem Mill" was a glorious address to have. Not far away in Heywood, SEI were making capacitors, ferrites and crystals in "Times Mill" David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done