WANTED- Germanium NPN transistors
EEYORE, Thu Aug 17 2006, 01:06PMHello all,
I am in need of a germanium NPN transistor. I need it to make a better Joule Thief for use in my fuel cell project.
Ive looked around, cant find any...
Thanks!
Matt
Re: WANTED- Germanium NPN transistors
Sulaiman, Thu Aug 17 2006, 04:15PM
For germanium you should think positive earth;
almost all germanium bjt were pnp - especially power-types
just as most silicon bjt are npn - especially power.
Just invert the diagram;
+Vbatt becomes -Vbatt
exchange pnp for npn and vice versa
invert/reverse all diodes and polar capacitors etc.
Sulaiman, Thu Aug 17 2006, 04:15PM
For germanium you should think positive earth;
almost all germanium bjt were pnp - especially power-types
just as most silicon bjt are npn - especially power.
Just invert the diagram;
+Vbatt becomes -Vbatt
exchange pnp for npn and vice versa
invert/reverse all diodes and polar capacitors etc.
Re: WANTED- Germanium NPN transistors
EEYORE, Fri Aug 18 2006, 03:10AM
No luck with them either...Seems ebay wants around 10$ total for just a small crappy old transistor!Why do they charge 5$ to ship a transistor that needs a lab scale to weigh?Hijueputa!
Matt
EEYORE, Fri Aug 18 2006, 03:10AM
No luck with them either...Seems ebay wants around 10$ total for just a small crappy old transistor!Why do they charge 5$ to ship a transistor that needs a lab scale to weigh?Hijueputa!
Matt
Re: WANTED- Germanium NPN transistors
Dr. Slack, Fri Aug 18 2006, 11:50AM
Surely you'll get them cheaper from a regular distributor.
Using RS in the UK, they want GBP1.49 for AC128 PNP, or GBP2.89 for the complementary NPN AC127 (just like silicon, the "other" polarity is available, but it's more expensive and not quite as well specified). These parts, along with the medium power AD161/162 pair, also tend to be stocked by the "old radio repair" suppliers, as both pairs were very popular in portable (ac127/8) and table top (ad161/2) radio output stages of a few decades ago.
If you can find a 70's tranny radio in a yard sale, it will likely have a few germaniums in it.
If you *really* can't find them in the US in digikey or ratshack, I could buy one here and post it at cost.
Dr. Slack, Fri Aug 18 2006, 11:50AM
Surely you'll get them cheaper from a regular distributor.
Using RS in the UK, they want GBP1.49 for AC128 PNP, or GBP2.89 for the complementary NPN AC127 (just like silicon, the "other" polarity is available, but it's more expensive and not quite as well specified). These parts, along with the medium power AD161/162 pair, also tend to be stocked by the "old radio repair" suppliers, as both pairs were very popular in portable (ac127/8) and table top (ad161/2) radio output stages of a few decades ago.
If you can find a 70's tranny radio in a yard sale, it will likely have a few germaniums in it.
If you *really* can't find them in the US in digikey or ratshack, I could buy one here and post it at cost.
Re: WANTED- Germanium NPN transistors
Marko, Fri Aug 18 2006, 12:44PM
I have few small germaniums around here like AC550, AC551, 2SB178 and even some wierd rusian things (name is written in Cyrilic!) and they are all PNP.
And several of AD465 power germaniums (big TO3)
Most are found in all those ultra-old stuff I used to dig out from school cabinet.
And they are indeed sold at some places for repair. Getting such a little thingy from somewhere arond the world would take ages..
Marko, Fri Aug 18 2006, 12:44PM
I have few small germaniums around here like AC550, AC551, 2SB178 and even some wierd rusian things (name is written in Cyrilic!) and they are all PNP.
And several of AD465 power germaniums (big TO3)
Most are found in all those ultra-old stuff I used to dig out from school cabinet.
And they are indeed sold at some places for repair. Getting such a little thingy from somewhere arond the world would take ages..
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