Transistor Interchange Guide ? NPN Germ.Trans.

Started by HOTTUBES, October 03, 2012, 01:43:56 AM

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HOTTUBES

i'm building a Dallas rangemaster at the moment , and i have all the components but the NPN Germ. Transisitor .....
is there a sub for the Germ. Transistor , does anyone publish an interchange guide so i don't have to keep bugging
the Forum for silly questions like this ... ( man i'm such a noob !!)





Thanks for any help !!

PRR

> publish an interchange guide

You would not be able to lift it.

Anyway the most complete interchanges I ever saw didn't cover every type ever made; lots of company-proprietary types.

And what might interchange in one circuit might not work in another.

The Rangemaster is not incredibly fussy.

Doesn't Small Bear offer known-good Ge devices suitable for such projects?
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joegagan

progress isn't always progress. in 2000, ECG had not yet been bought out by NTE.

you could go on ECG's website and download a transistor crossref program. it was a primitive one-sheet style program but it worked great.  when that computer bit the big one, that program was gone from me at least.  anyone still have this program? I posted a link to the ECG site, i recall aron expressing interest , but not sure if he snagged it.

it was the forerunner to this:
http://www.moyerelectronics.com/ECG-Cross-Reference.aspx
except the downloadable program allowed you to see every part number on the onesheet. you could also use your 'find" function.

also, back then, the datasheets were still easy to find online without seeing a jillion sites trying to sell you the datasheet.
my life is a tribute to the the great men and women who held this country together when the world was in trouble. my debt cannot be repaid, but i will do my best.

HOTTUBES

Thanks for the link !!

I'm just being impatient i guess , i have the cuicuit all built , i was hoping that i had something here that might work .
I may just have to wait and order a few AC127 , NTE103 or alike ....

joegagan

well , don't go thanking me so fast. that new ECG search thingie was altered after the NTE aquisition, i all it does is direct you to what by most accounts will be an expensive, iffy part. in 12 years, for every report of a good Ge from NTE there were a dozen reports of leaky or bad sounding Ges.

that cross ref is handy to find out if a part you found is npn or pnp if it is a somewhat obscure part number. but you can do that with a meter if you have the trans in  your hand.
my life is a tribute to the the great men and women who held this country together when the world was in trouble. my debt cannot be repaid, but i will do my best.

Scruffie

Just put an NPN Silicon in there for now if you just wanna try it, should work fine.

digi2t

How about the Russian GT404 tranny. I've tried them for fuzz, and they work fairly well. You have two gain ranges; 30 to 80, and 60 to 180.

Not too expensive, and generally reliable (dud percentage is low).
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Dead End FX
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smallbearelec

Yes, I have lots of NPN germanium RM devices, and they are necessarily expensive because the stuff that hits the "magic" gain buckets is scarce. But if you are willing to experiment a bit, you can have a "perfect" RM device for not much money. GO DARLINGTON!:

https://www.smallbearelec.com/HowTos/GeDarlingtons/GeDarlingtonPairs.htm

Read the article, then check my Stock List. I offer numerous low-gain NPN devices that can be paired up with not much cobbling, and the results can be amazingly good. I'm working on a design for a pedal/kit that I will call the "Oh My Darling(ton)" that will use this idea. I hope to offer that for sale soon after the Bare Boxes get here in a couple of weeks.

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LucifersTrip

Quote from: HOTTUBES on October 03, 2012, 01:43:56 AM
i'm building a Dallas rangemaster at the moment , and i have all the components but the NPN Germ. Transisitor .....
is there a sub for the Germ. Transistor

as PRR noted, it's not fussy...you can pretty much use any ge in approx the 60 - 100 hfe range, but more importantly, keep the leakage very low.

the Russian, like digi2t  mentioned (or the common 1T308/GT308's) usually have super low leak and work great

remember the geofex guide:
http://www.geofex.com/Article_Folders/Rangemaster/atboost.pdf
always think outside the box

pinkjimiphoton

Quote from: joegagan on October 03, 2012, 01:59:25 AM
progress isn't always progress. in 2000, ECG had not yet been bought out by NTE.

you could go on ECG's website and download a transistor crossref program. it was a primitive one-sheet style program but it worked great.  when that computer bit the big one, that program was gone from me at least.  anyone still have this program? I posted a link to the ECG site, i recall aron expressing interest , but not sure if he snagged it.

it was the forerunner to this:
http://www.moyerelectronics.com/ECG-Cross-Reference.aspx
except the downloadable program allowed you to see every part number on the onesheet. you could also use your 'find" function.

also, back then, the datasheets were still easy to find online without seeing a jillion sites trying to sell you the datasheet.

bro,
do you still have it bookmarked somewhere?
if you have a link, i may be able to find it on the internet archive for you...gotten pretty good at hacking past robots.
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pinkjimiphoton

russian mp16b's are pretty good in fuzzes, too...and cheap. i think i got a bag of 50 of 'em on evilbay for about 20 bux, and haven't had a bad one yet, use 'em all over the place.
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"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!
"try whacking the bejesus outta it and see if it works again"....
~Jack Darr