George White wrote in a message to Greg Mayman:

 GW> What I did hear of was the LOP switching transistor that caused one
 GW> manufacturers TV sets to go up in smoke. The developers used one
 GW> manufacturer, the factory purchasing got a better(?) deal from
 GW> another company. Unfortunately the secondary characteristics were
 GW> not the same, and not good enough, so Poof!, the set went up in
 GW> smoke... We approved both the device _and_ the suppliers. Puchasing
 GW> could not use an unapproved supplier...

I was reading the newsgroup sci.electronics.repair not all that long ago
and this sort of thing is _still_ going on.  Apparently the letter that's
at the end of the part number for Japanese transistors specifies a beta
range,  and using the wrong one in some repairs can still get you into
trouble.  This is complicated further of course by the low volume you're
dealing with in repair situations (where shipping and handling and other
charges can and sometimes do exceed the cost of the part itself),  and the
attempts by some manufacturers to "retain control" of the repair
process -- something that's not going to happen anyway and which is going
to backfire on them often.



 GM> No, what he needs is one that goes from uniploar to bipolar. The
 GM> 1489 receiver chip converts bipolar into unipolar.

 GM> The 1488 quad RS232 transmitter is the one to use. Of course it
 GM> inverts the signal, but that need not be a great problem.

 GW> Oops! Of course...

It still shouldn't be a problem.  This is just something that the design
needs to take into account.

I must admit,  it never would have occurred to me to use this chip for the
purpose,  but I don't see why it wouldn't work.

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