Germanium investigations

[Soundhappy]

Very interesting design from one of my favorite ing-s Kirkwood Rough. Link from this site:
Watt Sucking Fireball Series
.
Seems like very powerfull Ge device?
https://pccomponents.com/datasheets/MOTO--MP500.pdf

Modern design 😀 Motorola have produced bunch of powerful Ge's

 

[poynton]

On the page 133 chapter " Class A Output Stages " Mullard e-book year1960.
Some have tube driver and Ge power output
http://www.introni.it/pdf/Mullard - Reference Manual of Transistor Circuits 1960.pdf

It's a very interesting book .... I have a copy.


Andy

 

[v4lve lover]

I dug in the shed a bit.

I dug around in the shed, and found some AUY10 germanium PNP transistors.



Ft is supposed to be 60Mhz? and only 5w PC?


I found over 50 with the same date code, are these interesting?

 

[jpatay]

Good transistors to drive powerful 1T813. AUY10 - analogue of ГT905A (USSR).
GT905A = AUY10, 2N3732, 2N2147 transistor germanium 75V USSR Lot of 10 pcs | eBay

 

[Svjatoslav]

It is a pity that Ge JFET was not made serially.
They have a good characteristic.

 

[Soundhappy]

Special soldering technique for Germanium transistors

Protect your Ge crystal
Book in Italian with useful semiconductors equivalents list etc.

download link: https://ia802808.us.archive.org/13/items/manualtransistor/Manual transistor.pdf

Source: Manual transistor : La tecnica illustrata : Free Download, Borrow, and Streaming : Internet Archive

 

[Soundhappy]

Ge topologys list
Italian Ge book: Diodi al germanio e transistori : Sistema Pratico : Free Download, Borrow, and Streaming : Internet Archive

 

[Zoran]

It is a pity that Ge JFET was not made serially.
They have a good characteristic.

this type marked as Germaium JFET?
TIXM12

 

[Svjatoslav]

It seems so.
Interestingly, the Ge-device, but works at 125 degrees.

Thank you, Zoran!

 

[Zoran]

You are welcome 🙂

 

[jpatay]

It is good to measure germanium transistors with the Chinese TS-1.
The tester even shows reverse currents.
Transistor ГT404Г:

 

[Soundhappy]

Special for Germanium soldering post #346
Tips: use of pliers and crocodile clip 🙂

 

[JR_W]

I grew up building Heathkits, back then us ham fisted solder slingers used a heat sink on the leads of every solid state device.

 

[coolnose]

I guess AD149 will be for pre or headphone only...

 

[Soundhappy]

@ Coolnose

Or in class A amplifier driver stage before large output power transistor(s) 🙂

 

[Junm]

It is good to measure germanium transistors with the Chinese TS-1.
The tester even shows reverse currents.
Transistor ГT404Г:

Yes, I've use same kind of tester but there are some limitations for some Big Germaniums. They indicate C or damaged parts or unknown parts. However measurements using DMM is good. For small signal parts Ge are okay as well as all BJT, Jfets, Mosfet, Diodes and Capacitors.

 

[coolnose]

@ Coolnose

Or in class A amplifier driver stage before large output power transistor(s) 🙂

Yes, but then we have 3 stage amplifier, almost a heretic action in the PL section ..😛

 

[Soundhappy]

@ Coolnose

Normally Ge provide less gain..
It's depend on point of view if you don't need for external preamplifier additional stages
and can use passive volume control, then 3 or 4 active stages (input impedance buffer included)
such " integrated " power amplifier stays in minimalistic class A style :^)

 

[Soundhappy]

Yes, but then we have 3 stage amplifier, almost a heretic action in the PL section ..😛

For audio Designer even impossible is possible if innovate work 😀

 

[Soundhappy]

Germanium Power Transistors etc.
direct download : https://ia802701.us.archive.org/32/...d_68742623/1969_Transistor_DATA_Book_27ed.pdf
source:
derivationAndTabulationAssociates :: 1969 Transistor DATA Book 27ed : Free Download, Borrow, and Streaming : Internet Archive
Thanks to Archive.org