OLD Ex workshop spare parts and small manufacturing stock
Make no mistake, we are talking late 1960's ~ 1970's on this one - it has been sitting in the spare parts drawer under "what on earth will I do with this?" but now it is time to find a new home. Actually I do know that quite a number of VINTAGE audio gear, particularly musical equipment, uses these little babies.
Even as a museum piece, this semiconductor has its place in history! These short T01 red dot cases were the first all metal casing used after the Black series - the changeover occurred around the mid 1960's
These are some of my very old semiconductors, the cases are "dull" and the legs are a bit dull looking too - it happens when you get old!
I have cleaned up the legs just enough so that I could get reliable test results, results are below...
With these old devices (because I like to be sure and others have asked me for some basic testing to be done) I have grabbed a very basic transistor tester and the screen result is showing along with the device. The hFE measurement (DC current gain) has been printed onto the device casing, this is only a rough guide as the hFE will change depending upon temperature and Vce conditions.
If it is important for you to have particular devices (for matching as an example), please let me know which one(s) you would like to be supplied with, using the hFE as the reference.
MULLARD - Small Signal Transistor
Mullard
Made in England
Type: OC44N
Silver metallic outer case with the famous "red dot"
NOTE: due to the case oxidisation, two devices have the Red dots remaining and the other two you can see where the dot used to be but is no more! The manufacturer name and type number is always in the same place on the can so it is easy to figure out cbe although your handy transistor tester will do this for you anyway!
ALL devices can clearly be identified as MULLARD (although the print is faint!)
Germanium
PNP
Commonly used in low voltage, small signal output applications around 50 years ago!
Keep in mind the particularly low Vce of 15V
Manufacturers datasheets indicate a typical hFE around 45
Keep in mind that the hFE or even leakage currents are not the full story, it is HOW the transistor is biased that really matters.
Tested hFE's: 60,68,100,109 (each device has this test result printed on the side of the case)
Full part # on package (quite faint but readable) OC44N (MULLARD text) OK3
T01 case (straight line, Red dot denoting the collector)
BRAND NEW Old Stock
Clean legs, which could well do with a gentle (be very careful with these old legs) rub up/clean so that they can be soldered without issues.
*** Where the photograph shows multiple devices, this advertisement is for ONE device not all that are shown!
