[TriEmbed] Substitute transistor

The MacDougals paulmacd at acm.org
Sat Dec 18 14:01:58 CST 2021

I replaced the transistor with an exact match from ebay and a couple of electrolytic caps (at Carl’s suggestion).

The display is still dim.  Oh well.


---> Paul



From: TriEmbed <triembed-bounces at triembed.org> On Behalf Of The MacDougals via TriEmbed
Sent: Friday, November 26, 2021 9:11 PM
To: triembed at triembed.org
Subject: [TriEmbed] Substitute transistor


My microwave display suddenly went very dim.  I opened it up and found a discolored

spot on a circuit board feeding the display (see attached image).  That component is

marked B1238, so I assume it is a 2SB1238, which is obsolete.



Medium power transistor( 80V, 0.7A) 2SB1189 / 2SB1238 Features 1) High breakdown voltage, BVCEO= 80V, and high current, IC= 0.7A.

2) Complements the 2SD1767 / 2SD1859. Absolute maximum ratings (Ta=25C) Parameter Symbol Limits Collector-base voltage VCBO −80 Collector-emitter voltage VCEO −80 Emitter-base voltage VEB O −5 Collector current IC −0.7 C.


Anyone want to help me find a replacement?

I dug through my Dad’s stash of old electronics and found a TIP30B, which looks like it might work.



---> Paul


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20211218/ec86b599/attachment.html>

More information about the TriEmbed mailing list