Transistor substitutions?

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Sammas

Well-known member
Joined
Sep 30, 2004
Messages
547
Location
Sydney, Australia.
Does anyone know of a suitable replacement for the following?

MD708 which is a dual matched NPN transistor

&

MD984 which is a dual matched PNP transistor


I can't find anything about either of them.
 
http://www.datasheetarchive.com/search.php?q=MD708
Motorola - Semiconductor Data Library Volume 3 1974
http://www.datasheetarchive.com/datasheet.php?article=4364029

It is a very old part with no special virtue, except the Hfe is matched to 10%.

Use 2N3906 and 2N3904, or ANY cheap transistor. Buy a 10-pack, on-tape is nice. Odds are that two modern transistors from the same wafer will match to nearly 10%. If you think it matters (it may not), test the Hfe of several devices and sort. If you think thermal tracking is important, epoxy the flat-sides together and put a paper cap over the pair.
 
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