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DIY Stompboxes => Building your own stompbox => Topic started by: Jasonmatthew911 on March 30, 2013, 09:19:22 PM

Title: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 30, 2013, 09:19:22 PM
Hey guys, I'd like to make a simple little timer circuit that could turn a signal off and on while I press down on a momentary footswitch to create Killswitch stutter and Tremolo effects...Maybe just 1 Pot to control the speed or rate of the signal being cut off, and an LED to show the speed of the signal going on and off....I know there's a few pedals out there that do this kind of thing already, like the Perfect Square Hyperslicer, and Idiotbox Mad Doctor to name a couple, but it seems like it should be something very simple, afterall it's just something turning the signal off and on at slow to fast speeds...Does anyone here know a simple way or a simple circuit that I could implement to make this effect myself?...It seems like something simple that can be done with a 555 Timer chip, or am I wrong?....Any help would be great guys, thanks.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: haveyouseenhim on March 30, 2013, 09:38:06 PM
Burst box. I use it at every gig ;)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 30, 2013, 11:21:54 PM
Or would a 555/LDR acting as an LFO and Rate knob give the stutter effect for guitar?...If so, I suppose a transistor would have to be used to boost the guitar signal?...Or am I way off on this?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 30, 2013, 11:23:12 PM
Burst box. I use it at every gig ;)

Couldn't find much on the Burst Box....
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: mth5044 on March 31, 2013, 01:47:01 AM
You'd want a tremolo with a square wave LFO. A decent amount of the trem projects out there can do this, do a search for it on this forum. I'd look further but I'm being called to bed  :icon_redface:
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: haveyouseenhim on March 31, 2013, 01:54:14 AM
Burst box. I use it at every gig ;)

Couldn't find much on the Burst Box....

Sorry. I was being a smart ass. It was a god awful thread that happened here a while back. Didn't mean to throw you off.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on March 31, 2013, 08:24:26 AM
Hey guys, I'd like to make a simple little timer circuit that could turn a signal off and on while I press down on a momentary footswitch to create Killswitch stutter and Tremolo effects...Maybe just 1 Pot to control the speed or rate of the signal being cut off, and an LED to show the speed of the signal going on and off....I know there's a few pedals out there that do this kind of thing already, like the Perfect Square Hyperslicer, and Idiotbox Mad Doctor to name a couple, but it seems like it should be something very simple, afterall it's just something turning the signal off and on at slow to fast speeds...Does anyone here know a simple way or a simple circuit that I could implement to make this effect myself?...It seems like something simple that can be done with a 555 Timer chip, or am I wrong?....Any help would be great guys, thanks.

Yes the 555 would be a nice fit.
Problem with square LFOs is that they produce sharp transients on the power rail, which can easily turn into noise clicks on the audio path. And a hard mute on the audio can make an annoying pop
You will need to work around those issues:
- a clean and separate current and ground routing
- a linear ramping up and down of the audio signal. Short to look like a square mute, but long enough to not make audible "thumps"..
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 11:13:18 AM
Hey guys, I'd like to make a simple little timer circuit that could turn a signal off and on while I press down on a momentary footswitch to create Killswitch stutter and Tremolo effects...Maybe just 1 Pot to control the speed or rate of the signal being cut off, and an LED to show the speed of the signal going on and off....I know there's a few pedals out there that do this kind of thing already, like the Perfect Square Hyperslicer, and Idiotbox Mad Doctor to name a couple, but it seems like it should be something very simple, afterall it's just something turning the signal off and on at slow to fast speeds...Does anyone here know a simple way or a simple circuit that I could implement to make this effect myself?...It seems like something simple that can be done with a 555 Timer chip, or am I wrong?....Any help would be great guys, thanks.

Yes the 555 would be a nice fit.
Problem with square LFOs is that they produce sharp transients on the power rail, which can easily turn into noise clicks on the audio path. And a hard mute on the audio can make an annoying pop
You will need to work around those issues:
- a clean and separate current and ground routing
- a linear ramping up and down of the audio signal. Short to look like a square mute, but long enough to not make audible "thumps"..


What do you mean exactly by linear ramping up and down of the audio signal. Short to look like a square mute, but long enough to not make audible thumps?

Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 11:36:58 AM
Does anyone have a simple schematic or layout of a 555 Square wave LFO that shows clearly where the guitar input would be?...Should I have some kind of pre-amp section or small transistor Boost circuit to make up for volume loss, or is that not necessary?....I've seen a few circuits like the Tiny Trem and the SunTrem, but I'd like to just have a rate knob, with blinking LED, no depth knob, and do I need to use an LDR/LED?...I happen to have a couple of VTL5C3's laying around...On some of the schematics I found, I'm a little confused as to how to wire my "VTL" (LDR/LED)...Can anyone explain or make this simpler for me, I just want to have a clear picture of what I should and should'nt do from the beginning...I'd rather not deal with issues that probably already have solutions....I also saw a schematic of an LM386 Distortion with a 555 section for Stutter, and I noticed it was very simple with just 2 resistors, 2 caps, and a Rate pot with LED, no LDR, Can I just build a super simple transistor Boost with a simple 555 section for stutter using these minimal amount of parts with success, or will I have issues?...What does an LDR/LED combo actually do?... Hopefully some of you guys can help me further with this, thanks.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on March 31, 2013, 11:54:32 AM
if you cut the audio to an intant silence, the waveform gets cut abruptly, and most of the time you can hear som click and pop. This may not be an issue for a fixed switch, like a bypassswitch, but i find it quite noticeable and annoying in a tremolo pattern. Ideally, it should be cut at a zero corssing, or a more simple approach: a progressive change up and down.
Some tens of milliseconds for a softer transition may be enough. But you need a device that can be controlled this way.
An LDR is suitable, because its reaction has a "slow" reaction to light by itself.
A FET can be ramped but will ned some RC filter to get the soft control curve.

Another point to consider is how deep the isolation must be when silenced. I experience that in a square tremolo, you really expect that the silence has to be absolute on the low cycle. Otherwise, you'd still hear faintly the guitar, or not so faintly if there are gain stages after it...
The two design i had done for this effect:
- A very high ratio for a resistor+LDR divider: e.g. 1k + LDR, but needs to be buffered and amplified to unity after the divider
- Using an OTA, still tricky to balance headroom and noise.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on March 31, 2013, 12:11:13 PM
What i mean with the LDR:

If the LDR has a range from 1k light to 500k dark:
- Full ON this is a 1k/1k divider. You'll need to amplify after this x2 to get unity (or pre-amplify before)
- Full OFF this is a 500k/1k divider, signal is attenuated to 1:500, quite a lot...

Pre-gain can be just a unity gain buffer
For other specifications of LDR (you can measure it) you'll need to adjust gain to get unity


(http://i389.photobucket.com/albums/oo339/cpm_04/trem.png)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 12:21:46 PM
I'm basically trying to make an Idiotbox Cyclops Mono Stutter pedal it seems....Here's a pic of the inside guts I found, I see a VTL LDR/LED, an IC (probably 555), a couple of resistors, couple of LED's, a transistor etc...Can anyone make out what's going on here, it seems very simple, but I'm not really sure what is connected to what by just looking...
(http://[IMG]http://i85.photobucket.com/albums/k46/jasonmatthew911/Cyclops_Inside.png)[/img]
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on March 31, 2013, 12:22:39 PM
http://www.eleccircuit.com/simple-pulse-generator-by-ic-555-timer/
here it says:
the output frequency will be approximately 1kHz and the duty cycle 50-50, The output’s frequency is control by R1.
f=1/(1.4*R*C).

probably you'll want something in the range from 10Hz down
take the output through a resistor to limit the current appropiately to the LED and that all for that half of the circuit

The VTL is just a LED and a LDR enclosed in one package.



Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 12:26:13 PM
http://i85.photobucket.com/albums/k46/jasonmatthew911/Cyclops_Inside.png
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 12:29:13 PM
http://i85.photobucket.com/albums/k46/jasonmatthew911/Cyclops_Inside.png

Have any idea what is wired where in that pic?....That's really how simple I'd like to do this to fit in a very small enclosure, and this Idiotbox Cyclops seems to sound good in the demo videos as well.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on March 31, 2013, 09:43:35 PM
Can I just try something like the "Tiny Tremolo" circuit and use a VTL5C3 Vactrol, or should I be using something else for the LDR?...I ask because I happen to have a few VTL5C3's laying around....Also does the "Tiny Tremolo" really need any kind of buffer or is there no volume loss?....This is the version of the Tiny Tremolo I'm talking about trying:

http://www.diystompboxes.com/smfforum/index.php?topic=87322.0http://www.diystompboxes.com/smfforum/index.php?topic=87322.0 (ftp://http://www.diystompboxes.com/smfforum/index.php?topic=87322.0)

Would this Tiny Trem circuit and my VTL5C3 vactrol give me an intense stutter like a killswitch?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 01, 2013, 01:12:28 AM
After playing with 555s I don't recommend them at all, but to answer your earlier question about how to deal with the audio path, you would use the 555 as an LFO to drive the LED side of your vactrol.  Two problems with this approach:

1) As mentioned before, the 555 would drive the vactrol, but you might have a hard time trying to get the signal going through the LDR side of the vactol to be the same volume as the bypassed signal when you press the momentary foot switch.

2) To fix #1, you could use a little preamp circuit to adjust the stutter volume, but now you'd be sharing a ground with the 555 and it's VERY difficult eliminate the popping of the 555.

My recommendation is to get in touch with Jon Patton (Midwayfair) and ask him which LFO he'd recommend. He has at least one simple LFO that doesn't use a 555. You could just use the rate pot and use fixed resistors for the depth and wet/dry controls. As for the footswitch, just use a momentary switch instead of a latching one, and wire it the same as you would any other bypass switch.

I just thought of an option to deal with the volume difference between on and bypass states. Intead of using a bypass switch, use a momentary DPDT on the LED side of the vactrol to select between the LFO output and an uninterrupted voltage from your power supply. The guitar signal would always be routed through the LDR.  The LED would either stutter when the LFO is  powering it, or it would be lit constantly when the switch selects straight power. This option allows you to have two separate grounds and would probably eliminate the popping issue. You might still want to use a CMOS 555 to suppress the noise even further.

The downside of this option is that having your guitar signal always going through the LDR might negatively impact your tone. Also, you might still have popping problems if other pedals are fed from the same power supply as this pedal.

If you get this going, you'd do us all a huge favor if you would name it the Burst Box. The Burst Box is a mythical effect that at least one person believes exists, sort of like the Yeti. It would be good to have a real pedal with this name. See this thread for a laugh when you have some time:  http://www.diystompboxes.com/smfforum/index.php?topic=76932.0 (http://www.diystompboxes.com/smfforum/index.php?topic=76932.0)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 02, 2013, 10:56:42 AM
After playing with 555s I don't recommend them at all, but to answer your earlier question about how to deal with the audio path, you would use the 555 as an LFO to drive the LED side of your vactrol.  Two problems with this approach:

1) As mentioned before, the 555 would drive the vactrol, but you might have a hard time trying to get the signal going through the LDR side of the vactol to be the same volume as the bypassed signal when you press the momentary foot switch.

2) To fix #1, you could use a little preamp circuit to adjust the stutter volume, but now you'd be sharing a ground with the 555 and it's VERY difficult eliminate the popping of the 555.

My recommendation is to get in touch with Jon Patton (Midwayfair) and ask him which LFO he'd recommend. He has at least one simple LFO that doesn't use a 555. You could just use the rate pot and use fixed resistors for the depth and wet/dry controls. As for the footswitch, just use a momentary switch instead of a latching one, and wire it the same as you would any other bypass switch.

I just thought of an option to deal with the volume difference between on and bypass states. Intead of using a bypass switch, use a momentary DPDT on the LED side of the vactrol to select between the LFO output and an uninterrupted voltage from your power supply. The guitar signal would always be routed through the LDR.  The LED would either stutter when the LFO is  powering it, or it would be lit constantly when the switch selects straight power. This option allows you to have two separate grounds and would probably eliminate the popping issue. You might still want to use a CMOS 555 to suppress the noise even further.

The downside of this option is that having your guitar signal always going through the LDR might negatively impact your tone. Also, you might still have popping problems if other pedals are fed from the same power supply as this pedal.

If you get this going, you'd do us all a huge favor if you would name it the Burst Box. The Burst Box is a mythical effect that at least one person believes exists, sort of like the Yeti. It would be good to have a real pedal with this name. See this thread for a laugh when you have some time:  http://www.diystompboxes.com/smfforum/index.php?topic=76932.0 (http://www.diystompboxes.com/smfforum/index.php?topic=76932.0)

I checked out the Burst Box thread....Good stuff!...hahaha...Thanks...
I don't mind if there is a little popping, to me this is a Lo-fi effect anyways, I think a manual killswitch does a little bit of popping as well...Does the Tiny Trem 555 circuit have more popping than a manual killswitch would?...I know I can't expect that much from a 555, but I'll still use the CMOS 555 and a Momentary dpdt footswitch...So does the first version of the Tiny Trem have the volume loss issue?....If so, do you think that the little LPB transistor boost circuit would be a good option, I would want the volume with a fixed resistor, as I just want to have a Rate knob for a very small enclosure I have...Would a 100K resistor be too much for the fixed volume of the LPB boost circuit, or will I just have to test and see?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on April 02, 2013, 11:11:18 AM
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


Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 02, 2013, 12:35:23 PM
I haven't tried the 555 tremolo without a preamp (I used the Tillman preamp) so I don't know how much the LDR by itself is going to attenuate the volume.  The trick will be to get the LDR resistance as low as possible when the LED is on. The 555 circuits are pretty simple, so it wouldn't take much to get something going on a breadboard and find out what works and what doesn't.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 02, 2013, 04:13:43 PM
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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on April 02, 2013, 04:24:15 PM
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

Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 12:11:11 AM
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?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 10, 2013, 01:07:45 AM
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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 10, 2013, 01:16:28 AM
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:

(http://i1160.photobucket.com/albums/q485/jdansti/222794E1-A216-45D2-A88E-FE22C3C645F0-4310-0000062105127B57.jpg)


The fuzz first:
(http://i1160.photobucket.com/albums/q485/jdansti/6758F34B-52FE-4D6A-B9A2-4D2F5CC52290-4310-00000620FEADB960.jpg)

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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: J0K3RX on April 10, 2013, 03:18:30 AM
If you just want a stutter effect why don't you just install a momentary button on your guitar :icon_mrgreen:




Really cool...
https://www.youtube.com/watch?v=AlLxag9W4lU
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 09:20:44 AM
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:

(http://i1160.photobucket.com/albums/q485/jdansti/222794E1-A216-45D2-A88E-FE22C3C645F0-4310-0000062105127B57.jpg)


The fuzz first:
(http://i1160.photobucket.com/albums/q485/jdansti/6758F34B-52FE-4D6A-B9A2-4D2F5CC52290-4310-00000620FEADB960.jpg)

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?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 09:36:53 AM
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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 10, 2013, 11:48:28 AM
^ 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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 12:34:19 PM
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.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 12:59:58 PM
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.

Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: smallbearelec on April 10, 2013, 01:17:50 PM
For a working 555-based LFO:

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

SD
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on April 10, 2013, 02:20:00 PM
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




Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 03:06:46 PM
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!)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 03:24:23 PM
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...
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 03:44:55 PM
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)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jdansti on April 10, 2013, 04:59:06 PM
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)?
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 05:12:04 PM
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 thatīs what it looks like in the pic...Also, it does look like there is a transistor at the top...Iīve 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])

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 (ftp://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)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 05:16:51 PM
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...
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 05:18:50 PM
Your linkage...he no workee.
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: cpm on April 10, 2013, 05:45:37 PM
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!)

true, but a known impedance makes a reliable function of the LDR (recalculating values), and lower output impedance will play well with the rest of the chain.

a simple hack would be adding an inpur resistor, to make more like a pot: the combined resistor and LDR, and the wiper on the middle junction
A sufficiently big resistor (100k .. 1Meg...) would make any precedent impedance negligible, but... it wont swing to full volume, and following impedance will make less volume indeed when paralelled. Now the problem would be dealing with a high output Z

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

So it depends on what you expect from an overly simplstic circuit, talk about tradeoffs.
I think sometime it was noted some tremolo that actuated only by adding a DC level on the output, so the input stage of a tube amp would shift bias. Thats simple and clever, but no way reliable.
 

Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 06:18:18 PM

true, but a known impedance makes a reliable function of the LDR (recalculating values), and lower output impedance will play well with the rest of the chain.


Oh, I agree, it's better to work with a low impedance signal, but adding a buffer means changing the circuit, changing the circuit means it's then not a low parts count tiny tremolo!


a simple hack would be adding an inpur resistor, to make more like a pot: the combined resistor and LDR, and the wiper on the middle junction
A sufficiently big resistor (100k .. 1Meg...) would make any precedent impedance negligible, but... it wont swing to full volume, and following impedance will make less volume indeed when paralelled. Now the problem would be dealing with a high output Z

I can't recall what the dark resistance of a typical LDR is, but I'd imagine adding a high value resistor in series with the LDR would result in a significant guitar signal volume drop? (btw: I recall mentioning in the somewhat long 'tiny tremolo thread', that rolling off the guitar's volume pot will give a more pronounced tremolo effect, because rolling down the guitar volume places some series resistance in front of the LDR)
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 06:23:43 PM
Should this be in the Tiny Tremolo thread? haha
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Gurner on April 10, 2013, 06:28:53 PM
Should this be in the Tiny Tremolo thread? haha

Well you started it...!!

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?

Shouldn't that have been?  :icon_mrgreen:
Title: Re: ON/OFF Timer for an Auto Killswitch/Stutter Pedal?
Post by: Jasonmatthew911 on April 10, 2013, 07:28:44 PM
Should this be in the Tiny Tremolo thread? haha

Well you started it...!!

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?

Shouldn't that have been?  :icon_mrgreen:

Yeah it's my fault...This thread is related at least