ON/OFF Timer for an Auto Killswitch/Stutter Pedal?

[Jasonmatthew911]

you could do as simple as this:
http://www.diystompboxes.com/smfforum/index.php?topic=99839.0

on the tremolo part, thats a "brute force" attenuator, bad design and unpredictable interaction, but seems like its what you are asking for.

It can be done into many degrees of better, we have already sahred some hints and experience

Thanks for the help...Would you recommend this SunTrem circuit over the first Tiny Trem circuit that was posted in 2010 with just the rate pot?...One thing I'm not sure of with this SunTrem circuit, is the connection of the LDR...I noticed in the Tiny Trem version, that the LDR side has one leg to input and the other to output, and in this SunTrem schematic, it seems that both input and output are both connected to the same leg of the LDR...Does it make a difference?...Also, I suppose that the LED closer to the LDR would be how I should connect the LED side of my VTL Vactrol, right?...And the other LED above in the schematic would be for the enclosure to show the rate speed, right?...Do you have any idea if there is volume loss compared to the bypassed signal with this SunTrem or the 1st Version of the Tiny Trem, or will I have to add a pre-amp stage?...I know I can just start breadboarding to see what works and what doesn't, but I'm just trying to save time by asking all you experts first...hehe...I really do appreciate all your responses.

[cpm]

The "bad design" part is because the LDR in that SunTrem acts like half of an attenuator network (aka volume pot), the upper side of that "virtual pot" is the previous impedance, which may be quite different from a guitar pickup to different values of output impedance from other pedals. Additionally, it will also change with input impedances of following stages (pedals or amp). So.. a mess of uncertainties

Take the breadboard and test the 555 part until you get the LED controllable in the desired range.
From then on, you can try different circuits for the audio path with the LDR

[Jasonmatthew911]

I finally ended up breadboarding the Tiny Trem circuit and it seems to be working as intended, as long as I use it by itself or in front of other pedals as the first effect in the signal chain...As soon as I connect an overdrive or fuzz before the tiny trem, it seems like the Tiny Trem circuit gets completely ignored, like it gets bypassed or something, cuz you won't even hear the clicking sound in the background...To me it seems like when my distorted signal gets to the input of the LDR it just goes right through the output unaffected by the LDR/LED/555 circuit, since the input and output are connected to the same leg of the LDR on my breadboard...I have no dpdt switch connected at the moment...I'm doing all testing by connecting my overdrive pedals directly into the Breadboarded Tiny Trem circuit...This behavior makes no sense to me, as I've seen this type of effect connected after most pedals and the stuttering is very noticeable on any effect before this, as it should be turning all other effects on and off that are before it...This kind of effect should work best around the end of the signal chain, but right now for me it's only working as the first effect in the signal chain.....Does anyone have an idea why this is happening or what my issue is?

[Jdansti]

I suspect that it has to do with the separate grounds in the TT.  For an exercise and learning, you might want to get a piece of paper and draw out how the grounds are connected (or not connected) through your pedal chain with the TT at the beginning and also in the middle or end. I'll do the same on my end because I'm curious. I'll check back with you.

[Jdansti]

What happens when the OD pedals are in bypass mode?  Do you still lose the chopping action?

Edit:

Are you using the same power supply (i.e., with the same power ground) for your TT and your other pedals?  If so, try running the TT with a 9V battery and the other pedals with the power supply and see what happens.

Ok, I've got a couple of drawings which hopefully represent most of what you've got.

The TT first:




The fuzz first:


If the TT's LDR is not grounded to the same "ground" as the main signal, this might be why it's not chopping when it's placed behind another effect. But if that's the case, how is the signal ground making it to the amp?  The only way that I can see this happening is if the power ground is providing the path through the effects. But if thats true, then it wouldn't chop at all when it's in the lead position... But...

The drawings are probably not exactly what you have, but maybe they'll help if we make them the same as your conditions.

[J0K3RX]

If you just want a stutter effect why don't you just install a momentary button on your guitar




Really cool...
https://www.youtube.com/watch?v=AlLxag9W4lU

[Jasonmatthew911]

What happens when the OD pedals are in bypass mode?  Do you still lose the chopping action?

Edit:

Are you using the same power supply (i.e., with the same power ground) for your TT and your other pedals?  If so, try running the TT with a 9V battery and the other pedals with the power supply and see what happens.

Ok, I've got a couple of drawings which hopefully represent most of what you've got.

The TT first:




The fuzz first:


If the TT's LDR is not grounded to the same "ground" as the main signal, this might be why it's not chopping when it's placed behind another effect. But if that's the case, how is the signal ground making it to the amp?  The only way that I can see this happening is if the power ground is providing the path through the effects. But if thats true, then it wouldn't chop at all when it's in the lead position... But...

The drawings are probably not exactly what you have, but maybe they'll help if we make them the same as your conditions.

For now I tested them with separate power supplies, so for the power they aren't really sharing the same GND, but they have the input/output GND in common....As long as I have the TT first it chops the other effects, but if I put it after any other effect, it gets bypassed only when the other effects are ON...If I bypass the effects before the TT, then it starts chopping again...So it works on it's own no matter where it is in the signal chain, or it works as the first effect in the chain, but basically if I have any effect engaged before the TT, then it doesn't chop at all...This is odd to me....I'll try running them both on the same supply later and see if it reacts differently I guess...Do you have a better idea now of what could be happening?

[Gurner]

From recollection, the Tiny trem works only on high Z sources...as soon as you put an effect inline (in front), your signal then becomes Low Z & it's effect is somewhat nulled.

[Jdansti]

^ Re: hi/lo z, would this be related to signal amplitude going into the TT?  For example, a high gain pedal's output amplitude could be much higher than the guitar's. A way to test this would be to dial down the volume of the OD pedal in front of the TT and see if it starts chopping.

Another related thought is that if the LDR's resistance is not low enough when its LED is on, a "stronger" signal is getting past the semi-short to ground. (Sorry for all of the non-tech language). A way to test this would be to replace the resistor on the LED with a 1k pot (or trimmer) and slowly dial the resistance down, causing the LED to get brighter, and see if it starts chopping. Keep in mind that you might blow the LED if the resistance gets too low. You could place a 300R resistor in series with the pot to protect the LED.

[Jasonmatthew911]

From recollection, the Tiny trem works only on high Z sources...as soon as you put an effect inline (in front), your signal then becomes Low Z & it's effect is somewhat nulled.

There must be a simple way to change this, right?...Because I noticed that the Idiotbox Cyclops Mono stutter is a circuit based on the simple 555/LDR/LED combo and I saw many demo videos where the idiotbox Cyclops and Mad Doctor Stutter were placed after other effects and it still chops the signal very well.

[Gurner]

There must be a simple way to change this, right?...Because I noticed that the Idiotbox Cyclops Mono stutter is a circuit based on the simple 555/LDR/LED combo and I saw many demo videos where the idiotbox Cyclops and Mad Doctor Stutter were placed after other effects and it still chops the signal very well.

Couldn't find the schem for that circuit.

I'd describe the tiny trem as more of a polite kill switch (it's working in a similar way) vs. a conventional way of  modulating signal volume.

Think of a volume pot being turned down/up with your hand (with the output being on the wiper lug) - that's what I'd call conventional tremolo.

Now think of a High Z signal being loaded down heavily by switching in/out a low value resistor - that's what the tiny trem is doing.

[smallbearelec]

For a working 555-based LFO:

https://www.smallbearelec.com/Projects/TremBear/TremBear.html

SD

[cpm]

From recollection, the Tiny trem works only on high Z sources...as soon as you put an effect inline (in front), your signal then becomes Low Z & it's effect is somewhat nulled.

There must be a simple way to change this, right?...Because I noticed that the Idiotbox Cyclops Mono stutter is a circuit based on the simple 555/LDR/LED combo and I saw many demo videos where the idiotbox Cyclops and Mad Doctor Stutter were placed after other effects and it still chops the signal very well.

yes, put a buffer to achieve a known impedance for the following stages

[Gurner]

From recollection, the Tiny trem works only on high Z sources...as soon as you put an effect inline (in front), your signal then becomes Low Z & it's effect is somewhat nulled.

There must be a simple way to change this, right?...Because I noticed that the Idiotbox Cyclops Mono stutter is a circuit based on the simple 555/LDR/LED combo and I saw many demo videos where the idiotbox Cyclops and Mad Doctor Stutter were placed after other effects and it still chops the signal very well.

yes, put a buffer to achieve a known impedance for the following stages

If you put a buffer in front of the tiny tremolo, that won't work as it'll make the High Z guitar signal, a low Z signal (which is the actual issue here  ...i.e. putting an effect pedal  before the tiny tremolo essentially makes your guitar's signal signal Low Z)...putting a buffer in front of the tiny tremolo would would then need a circuit re-design to make it work ...but then it wouldn't be the tiny tremolo - e.g. check out the component count of the tremolo SD posted a couple of posts above (& I dare say "The not so tiny tremolo" hasn't quite the same appeal!)

[Jasonmatthew911]

From recollection, the Tiny trem works only on high Z sources...as soon as you put an effect inline (in front), your signal then becomes Low Z & it's effect is somewhat nulled.

There must be a simple way to change this, right?...Because I noticed that the Idiotbox Cyclops Mono stutter is a circuit based on the simple 555/LDR/LED combo and I saw many demo videos where the idiotbox Cyclops and Mad Doctor Stutter were placed after other effects and it still chops the signal very well.

yes, put a buffer to achieve a known impedance for the following stages

Kind of weird that the Tiny Trem wasn't designed with this in mind, because normally you want a Tremolo effect to be around the end of the signal chain....Also, I don't completely understand how a buffer would help this, if putting an overdrive pedal before it is kind of the same thing, isn't it?...Also weird that the TT works fine as the first effect going into others, it still chops the signal, but anything ON before the TT just bypasses the TT...

[Gurner]

Also weird that the TT works fine as the first effect going into others, it still chops the signal, but anything ON before the TT just bypasses the TT...

It's not so weird ....your guitar signal is high impedance & the tiny trem can 'drag it down' with its modest LDR (i.e. shine light on the LDR its resistance goes low & loads the guitar signal), whereas the same LDR in that configuration can't drag down a signal coming out an active device (opamp etc)

[Jdansti]

CALLING DEAD ASTRONAUT........



Rob-Would you please let us know if your Tiny Tremolooooooooo works in any position in the pedal chain (or try it if you haven't already)?

[Jasonmatthew911]

Also weird that the TT works fine as the first effect going into others, it still chops the signal, but anything ON before the TT just bypasses the TT...

It's not so weird ....your guitar signal is high impedance & the tiny trem can 'drag it down' with its modest LDR (i.e. shine light on the LDR its resistance goes low & loads the guitar signal), whereas the same LDR in that configuration can't drag down a signal coming out an active device (opamp etc)

The image below is a gut shot I found online of the Idiotbox Cyclops Mono Stutter pedal, unfortunately that's all I got to show, but it proves that this should work with a simple circuit...It kind of looks like it's based on the Tiny Trem circuit, though it looks like the input connects to the + side of the LED vactrol, and the output connects to one of the LDR legs, at least that´s what it looks like in the pic...Also, it does look like there is a transistor at the top...I´ve seen demos of this pedal connected after other pedals and it still chops the signal very well...Any idea how he accomplished this keeping the circuit simple?....I was really trying to make something small and simple, but effective, in order to fit in a very small enclosure I have...It just seems like there must be a simple solution for this, if that simple circuit of the Cyclops works just fine...



http://s85.photobucket.com/user/jasonmatthew911/media/Cyclops_Inside.png.html?sort=3&o=0#/user/jasonmatthew911/media/Screenshot2012-03-27at101424AM.png.html?sort=3&o=1&_suid=136562667907809878344870726312

[Jasonmatthew911]

http://i85.photobucket.com/albums/k46/jasonmatthew911/Cyclops_Inside.png

Sorry, the link to the guts of the Cyclops pedal I'm talking about is above...

[Gurner]

Your linkage...he no workee.