digital dimmer help.

[roo7flat5]

I've knocked up this circuit using a lm339 comparator and 555 timer
(AND8011/D) at
http://onsemi.com. I've used a BTA-16-600B triac, and an MOC3022 triac
trigger, which won't trigger the triac. The output waveform at the
transistor(pn100) seems o.k. and will light a led, but won't trigger the
bilateral switch. Any helpful suggestions gratefully received.

 

[John Crighton]

On Sun, 16 Nov 2003 11:54:40 GMT, "roo7flat5" <roo7flat5@dodo.com.au>
wrote:

I've knocked up this circuit using a lm339 comparator and 555 timer
(AND8011/D) at
http://onsemi.com. I've used a BTA-16-600B triac, and an MOC3022 triac
trigger, which won't trigger the triac. The output waveform at the
transistor(pn100) seems o.k. and will light a led, but won't trigger the
bilateral switch. Any helpful suggestions gratefully received.



Hello,

just a thought, test your triac on its own, using a low voltage
supply, to make sure it isn't dud.
http://www.uoguelph.ca/~antoon/gadgets/scrtest.html
http://www.repairfaq.org/sam/semitest.htm#sttth
Regards
John Crighton
Hornsby