GEC is the General Electric Company of England, not the one from the U.S.A. These are occasionally branded as Mullard. Full writeup on GEC / GET transistors can be found here
From what I've seen, the most common one available at the moment is the GET113. I have a few, and they're well worth a try if you see them at a good price.
GEC GET 102 - 114 GERMANIUM TRANSISTOR DATA
Type V Max Hfe P Max (mW) I Max f (Mhz)
GET102 30 100 200 1000 1.5
GET103 30 55 200 1000 1
GET104 30 55 200 1000 1
GET105 40 30 800 1000 0.9
GET106 15 55 200 1000 1
GET110 40 20 800 1000 1
GET111 60 55 200 1000 1
GET113 15 100 200 1000 1.5
GET114 15 55 200 1000 1
TRANSISTOR EQUIVALENTS
I saw many Germanium transistors produced in the 1960s in the local markets when I was on a business trip in Wuxi, China, and Hanoi, Vietnam. The models were unfamiliar to me, mostly labeled as 3AXxxx and 3GXxxx, all of them were new and unused with parameters listed on the packaging. Can I purchase those transistors by comparing them with the parameters you provided?
ReplyDeleteMost transistors used in pedals were also used in radios for IF amplification, pre-amplification or in the driver section. The transistors you mention are the same type - you never know, they might be really good to work with. If they're cheap, I'd say buy a few and see how they work.
DeleteThis might be helpful
http://www.wylie.org.uk/technology/semics/China/China.htm
Chinese germanium transistors seem to use a number of standard series (however, there are probably interesting early anomalous types of which I am unaware):
high-power PNP types in the 3AD series, starting with 3AD1.
low-power PNP AF types in the 3AX series.
low-power PNP IF/RF types in the 3AG series.
low-power PNP RF/switching types in the 3AK series.
low-power NPN IF/RF types in the 3BG series.
probably analogous 3BD, 3BX and 3BK series although I have not seen any.
probably others of which I am unaware.
Thank you for your response. I will use the parameters you provided as a reference and have my colleagues there purchase some items. I bought some AC128 transistors produced in Shenzhen, China . I will try using them to build something.
ReplyDeleteNo problem Ding. I've seen some good reports for the 3AX31C - I'll have to try some too
ReplyDelete