simple cmos lfo is too good to be true

Started by BigTexas, December 19, 2005, 10:30:39 PM

Previous topic - Next topic

BigTexas

hi y'all, found this cool simple single/dual triangle lfo hoping i could fix it up to work with some guitar pedals but it hasnt quite worked yet.

i made the mistake of making TWO of these on perf before i went and tried it out on a breadboard. the schematic comes from a paia related modification found here: home1.gte.net/res0658s/fatman/4069_lfo.html

it uses half of a 4069ube ... i was trying to get it into a little vactrol with the 4069 pushing my led inside of it. I cant get it to flash or do anything! it seems to either want to be dead or completely lit up. please help! also note i never had a 1.3uf capacitor but i tried .1uf, .22uf, 2.2uf, and up as well as switching the elec caps even though i believe the schematic says the positive should go towards to lfo's output. Thanks!

gez

It's probably latching.  Make the 100k smaller - the resistor that connects from '6' to '1' in the schematic - try the next value down.
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter