HISTORY:
Sustainability is the name of the game! Anything (that has been tested and still functioning properly) should be repurposed creating saving in wasted Ee and reducing the poisoning our environment when items are buried in the earth at the local tip needlessly.
Never heard of Ee? It is a concept that creates a measurement of ALL things (not just electronics) that humans have made and the energy used in obtaining the raw material, processing the materials right through to a finished product and even should include the shipping of the item to the distributors/retailers.
If you would like to know more about Ee values, please take a look HERE
This electronic component is BRAND NEW, old (very old, around 50+ years!) stock.
How long since you've seen some Germanium transistors? These were in common use way back when I was a teenager in the late 1960's, I cut my teeth on devices such as this - this was the beginnings of the "new fan-dangled" semiconductor technology around that period
Up until this time in the 1960's valves were "the" thing, then along came these little beasties!
This device has "mystery" stamped all over it! I do not know who manufactured it, there are no ID markings other than the part number (or it could even be an OEM part number) but I will describe what I have here in my hand as best I can.
UNKNOWN MANUFACTURER - Germanium Transistor
Made in an unknown country but suspect either England or USA
Circa late 1970's (50+ years old!)
Type: E53125
Batch code: 6015
PNP
Germanium junction semiconductor
TO-5 style case with the small side tab (the lead nearest this is the Emitter)
Case appears to be metal but is completely covered in a dull Black paint
On the underside however it looks all the world like epoxy resin!
The legs are all gold plated
WARNING!
If ever the new owner was considering using this device, NEVER bend the leads less than 1.5mm from the body. The packaging used in the early days of transistors was often quite delicate and if you make a bend in the lead which is too close to the body, the lead is likely to snap off!
COSMETIC CONDITION:
Amazing after all these years sitting in my spare parts drawers quite frankly!
NO physical damage
Legs are straight(ish) 27.5mm length each
NOTE: Although all transistors have never seen any solder, ONE transistor has "shorter legs" - Emitter is 27.5mm, Base lead is 24mm and the Collector is 16.5mm. Why? No Idea! I have looked very closely for tell-tale solder marks or even at the shape of the leg "cut" but it really does appear to have been prepared for use but never actually installed.
TESTING:
It would have been nice to test these with a semiconductor curve tracer to get a much better idea about suitable circuit design but alas, my curve tracer has already found a new workshop to live in! Best I can do is test it with a simple transistor tester to determine the basic characteristics of Hfe and device type.
I currently have 3 of these devices,
Hfe results were 55, 63 & 75
All are confirmed as Germanium transistors
I have written in VERY SMALL numbers the Hfe for each device under test, black pen and underneath where I observed this "epoxy like" material
