tiny tremoloOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

[Derringer]

Rick's saying in series with the LED, not the LDR

which  would limit the brightness of the LED, which I'm thinking would serve as a depth control, but would also decrease max volume as the resistance was increased because the LED wouldn't reach max brightness. But then again, it all depends on just how sensitive the circuit is ... i.e. at what brightness is most of the signal getting through.

what if the guitar signal were jumpered from input to output and the LDR was placed between the signal and ground. That way, you'd have max signal when the LED is dark, and the signal would be bled off to GND when the led lit. If you added the proposed depth control here, the volume of the output signal would be unaffected.

and I'm just thinking out loud here too ...

cool circuit Rob

[Perrow]

Thinking out loud...Led "off" means (?)megs of resistance between in/out, 5K between out in
with the LED on as "stock". With a pot in parallel you would get less resistance with LED off
and' therefore a less deep trem no? But I wonder how big that pot would need to be.
Probably larger than 1M 

That's what I said a few posts ago:

If I'm not totally mistaken, a pot in parallel with the ldr would constitute a depth mod, wouldn't it?

But I don't think it would have to be larger than 1M, I think you could get away with 500k or even 100k, sure it would mean less tremolo, but not that much less, according to the first online calculator a 5k and a 100k resistor in parallel is 4.67k I don't think that would be too much

[Perrow]

what if the guitar signal were jumpered from input to output and the LDR was placed between the signal and ground. That way, you'd have max signal when the LED is dark, and the signal would be bled off to GND when the led lit. If you added the proposed depth control here, the volume of the output signal would be unaffected.

and I'm just thinking out loud here too ...

cool circuit Rob

Oh, that's an idea. Think the jumpered signal would have to have a resistor as well to get a 5k ohm to ground to bleed off enough signal, maybe this is where the input buffer comes in to boost the signal enough for this to work. I like this idea as it doesn't affect the "on volume", I like the other idea for its simplicity , and how much does 5k resistance do for the volume?

For a more complex solution, how about a dual gang "balance pot" to blend between the untremoloed (how about that for a word) and the tremoloed signal

[John Lyons]

Rick's saying in series with the LED, not the LDR
Doh!, missed that one...

[Perrow]

Humored myself with doing a pcb design a la tiny



Had to remove the rate led ground from the board to remove a row. It's getting to the point where you can sticky tape the board to the side of your 3pdt    With effects this size we're getting to where dual effect in 1590A's is possible.

As for in pot in series with led, I didn't think you could dim leds that way, can you? (edit: thinking about it well yes you can)

ps. If somebody cares to etch this design I'd be interested in one. I've only gotten to where I design pcb's, not to the point where I actually etch them  

[Barcode80]

Humored myself with doing a pcb design a la tiny



Had to remove the rate led ground from the board to remove a row. It's getting to the point where you can sticky tape the board to the side of your 3pdt    With effects this size we're getting to where dual effect in 1590A's is possible.

As for in pot in series with led, I didn't think you could dim leds that way, can you? (edit: thinking about it well yes you can)

ps. If somebody cares to etch this design I'd be interested in one. I've only gotten to where I design pcb's, not to the point where I actually etch them  

I'll etch it sometime in the next couple of days. PM me your address and I'll mail you one.

[Perrow]

I'll etch it sometime in the next couple of days. PM me your address and I'll mail you one.

Thanks, I'll post a slight update to the design tonight (about 12-14 hours away).

[deadastronaut]

wow a pcb already!...nice work guys.

definately needs a depth mod though!...i'll try the 100k on the led idea!..should work i think..
anyone else tried it yet?....

edit: yay!..it works...dims to nothing too. excellent!!!!!....

it only works on the end of the 100k pot though!!!!.....i'll ttry a different value on it....

[frequencycentral]

I have been thinking about the depth pot idea (100k pot in series with the LED). The way you've got the LDR configured, my depth pot idea would affect the 'on' volume as well as the 'off' volume. I think? However, instead of running the audio through the LDR, connect the input and output together and run the LDR from the input/output to ground - like a pulldown resistor. That way the LED in series with a 100k depth pot will just affect the depth and not the 'on' volume.

[deadastronaut]

cheers rick , i'll try that..

just tried it with a 1k linear  pot...i get the full range over the pot and it dims brilliantly now......

it almost goes completely off to bright ok...

[Perrow]

Update coming faster, moved in and out to top. Just slightly annoyed at the rate led connection  



Edit: if someone comes up with a modified schematic, I'll give that a go as well.

[deadastronaut]

nice...could just jump the led ground!!!..

the 1k pot idea works...but im sure its changing the speed slightly too when turned up/down....

[deadastronaut]

aha..i tried ricks/derringers idea...used the ldr as a pull down resistor...

join in/out with ldr to ground....put 1k pot in series to the led....brilliant works a treat!!!!...

so hold off on that pcb perrow!!!!...

heres the updated vero layout with depth....works ok guys...thanks for the ideas..!

[deadastronaut]

i'll do a sounclip of this later , will have to wait till it gets dark....
still havent shrink wrapped it yet!!!
its 4:15am here!!!!..few hours to go

[deadastronaut]

heres the clip guys....top tip though use a 3mm led for the enclosure speed rate led...
i wrapped the led/ldr...

the 5mm was being drained too much.

works great..can get really subtle too...i still liked the original chop too though..might make that  switchable!!!!!!

http://dl.dropbox.com/u/7464107/tinytrem2.mp3

im a very happy bunny...

[daverdave]

It's pretty square. I wonder if you could add in a smoothing cap to round out the waveform?
Sounds cool for more angular trem, nice!

John

You can get a kind of triangle wave off the charging cap, a bit of an exponential curve on it, not sure how big it'd be though. Should be easy to wire a swicth in to select between them.

[John Lyons]

So a larger cap there in place of the 47uf then?
Something that take longer to charge and makes the
angle less steep, Is that correct?

[Quackzed]

Question: if the ldr is going to ground, does that mean the input and output impedence varies with the r of the ldr?
If so, you could potentially drive it with something that needs a high impedence input and get a wah/filter sound out of it?
just an idea that popped into my head.
sounds great btw.
1 chip 1 resistor 1 cap
1 ldr and 2 led's

[Perrow]

With the ldr to ground as a drain cap, couldn't a depth pot be added in series with the ldr? More minimum resistance drained to ground = less depth.

I'll hold on the next version, even though I got two of them ready, one even smaller than before

[deadastronaut]

@john i tried a 100uf and it just makes the speed rate longer....havent got a scope to see waves etc..

@ quackzed...i like the idea of that!!!...that would be very cool indeed....but i lack knowledge on how to achieve such an effect..  

@perrow...tried that...works really well too...