2n3773 source

Disabled Account
Joined 2004
Hi, i need to find 2 good original toshiba 2n3773 to replace in a BGW amp.
I bough two from ebay and did try to charecterize them on my tektronix curve tracer, without surprise they dont match at all my good old ones...most probably chinese knock offs.
My old good ones are all hfe matched around 30, reverse leakage is all around 160-180v. I know there are several other test to characterize them.

The motorola act weird on the tracer but where actually used in this amp for years, but prefer to replace them.

so what are known good sources for theses ?
are the ones from mouser/digikey (On semi) a reliable source ?

thanks !
 

Attachments

  • 2n3773_1.jpg
    2n3773_1.jpg
    377.6 KB · Views: 157
  • 2n3773_2.jpg
    2n3773_2.jpg
    427.5 KB · Views: 159
  • 2n3773_3.jpg
    2n3773_3.jpg
    372.2 KB · Views: 155
All real Toshiba TO-3’s have that heat slug insert that the ones on the left have (marked 32 and 33). Any “Toshiba” To-3’s that don’t are fake. You won’t find Toshiba “2N3773’s” (aka 2SD873) new anywhere. I have found a handful of surplus over the years. They are good transistors, but don’t expect to find them when you’re actually looking for them.

The older Motorola’s often act weird testing Hfe at low currents. Many of the old epi-base types do. Newer ON versions are better behaved, but measure more like an MJ15003.

The BGW amps used to use selected devices, since they were running the 3773 above its 140 volt VCEO rating. It is safer and easier to just use MJ15024’s, because you don’t need to bother screening them, except a vbe or beta match if you choose to. And you’re more like to be able to match them than you will the 3773’s.
 
WG_SKI thanks very much for the details.
i saw several posts about thoses with the slug insert and was aware of the copy.
i have some MJ15024 in hand from On semi i guess i will use them instead of the copy....