Re: Looking to Cross ref a Diac & Triac set

In article <46256ABB.11328C3B@xxxxxxxxxxx>,
rabbitsfriendsandrelations@xxxxxxxxxxx says...


Tim wrote:

Hello again, I have a circuit for an electronic Variac that uses a Diac
and Triac to control the output. It looks like a glorified dimmer
circuit. Anyways it uses part # MAC2-4 for the triac and MPT-28 for the
trigger diode (diac). I haven't been able to cross reference these
puppies on the net. I hav checked the usual sources, but came up empty.

They're ancient, that'll be the problem !

Graham


Hmmm, this circuit was drawn in 2005, August 18th to be exact. It's
strange that the guy used old parts in the design. It also appears that
he has spec'd and drawn a triac, but the pins are marked cathode, anode
and gate, like an SCR. I think it should have MT1, MT2 and gate for a
triac.

The schematic is here;
http://homebrewradio.tripod.com/id58.html

- Tim -
.

Relevant Pages

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