tremo-kill

[vendettav]

hey guys, been thinking on this idea for awhile, and tho i can't seem to put it in a circuit format yet but the idea is:
to take a 55 chip and wire it as a metronome and put a transistor switch in the end that shunts the signal to the ground when on so having a on/off tremolo, I'm guessing if you put pots for both R1 and R2 you can have a nice auto kill but with a different lenght for kill and normal position.



on the other side, I don't have much knowledge on transistors as switches so if anybody is willing to give me some info (I read some stuffb ut didn't get much out of it) I could may be try out this idea?? thanx

[vendettav]

ok so the idea is to put a 10k resistor at the lug 3 (taking the piezo and anything following the lug 3 on the scheme i put up in my post out of course) that goes to the Base of a npn tranny. the emitter of the tranny goes to the ground and the collector is connected with a 300ohm resistor going to the +9v. this way when 555 is giving a voltage out the npn is open and shunts collector to the ground. Now connecting input and output to the collector will shunt output to ground when npn is on, so this way we get the square wave tremolo, so finally adding a cap at the output to filter out DC hum and the circuit is ready. tho i wonder if 555 will make any noise in there

anyways what do you guys think??

[smallbearelec]

The biggest issue with using a 555 in any sort of trem is preventing it from imposing "ticks" on the audio when it switches. It's been done successfully, but it takes careful attention to both circuit design and board layout. The CMOS version of the chip is a better choice. Search past Forum threads on the subject and get out your breadboard. You may also want to look at the design of my Tremulous Bear in Projects on smallbearelec.com.

Regards
SD

[deadastronaut]

yep.. the 555 is notorious for ticking..

try dropping the voltage into it...i stuck a 2.2k from 9v to v pin....that worked ok..on a cmos ts555cn....depends on the project though i guess!...

just a thought...

[anchovie]

DC hum

Hum is a waveform and therefore AC.

[vendettav]

DC hum

Hum is a waveform and therefore AC.

ah well yeah sorry, I actually didn't know. but then should i say DC noise?


Yeah I've heard that CMOS is the better choice, Tho i only have a NE555 if im not mistaken.

Oh well guess I'll be better off breadboarding one now

hope i can get some time today

[vendettav]

hmm i got the thing going. did the job really but A. it drops the volume a bit for some reason and B. it doesn't really KILL the signal entirely
now i dont know what it could be for. oh and C. of course it ticks >_<

any ideas on A and B at least?