I was wondering if any of the photocells at futurlec are suitable replacements for the optoisolator in the schematic? Specifically I'm looking at photocell 3. does anyone read that dark resistance as 1M?
http://www.futurlec.com/Photocells.shtml (http://www.futurlec.com/Photocells.shtml)
(http://i642.photobucket.com/albums/uu144/kupervaser/230.png?t=1233685653)
datasheet for the clm50 shows 5K to 1M resistance. it can be viewed at http://www.alldatasheet.com/view.jsp?Searchword=CLM50&q=CLM50 (http://www.alldatasheet.com/view.jsp?Searchword=CLM50&q=CLM50)
any help would be greatly appreciated. thanks so much
In my experience photocells are mostly interchangeable... Slight adjustments to the circuit may be needed in the occasional case but usually you can just stick any old photocell under the sun in and it will work well.
The LED only really makes a difference based of effeciency - a superbright will need a bigger current limiting resistor to match the response of a normal LED, for example...
If your photocell is on average a lower resistance then it should be then in your schematic you can just lower the 22k resistor in the feedback path of the second op amp to compensate, if it is too high then raise it...
By the way photcell 3 says 5000k, which equals 5meg. Photocell 10 is your best match, but it is larger. Photocell 2 would be the second best match. But like I said it doesn't really matter all THAT much.
You're right, i actually meant to type photocell 2. good call on the photocell 10, i didn't even notice that one's light/dark characteristics. Thanks for the second set of eyes!
I thought I'd just reply to this old post rather than creating a new one, as it's kinda along the same lines.
Necroposting?
(http://i48.tinypic.com/120jajq.png)
Anyway... I'm building the DOD 230 from this vero: http://diy-layout.com/67 (http://diy-layout.com/67)
(http://diy-layout.com/diyl/67/render)
I'm a little bit confused how to hook up the VTL5C10 or the LED/LDR combination.
The VTL5C10 has 4 legs and I can't really see where they might go on the vero?
Is that what the green lines are about?
If I were to make my own LED/LDR combination, how would that be hooked up?
Thanks for helping out :icon_biggrin:
(http://i50.tinypic.com/2whmv0m.gif)
Like this?
(http://i49.tinypic.com/35056s9.jpg)
Hmmm that didn't work :icon_sad:
Has anyone built this one?
Well it looks like you put the vactrol in the right place, that's a good start. But no, I haven't built it.
Hmmm I'm still having no luck.
I took the octocoupler out and put in a red 5mm LED just to test it... and the LED stays full brightness even with no input!
That doesn't seem right...
Also, the VTL5C1 or VTL5C3 were suggested as suitable octocoupler replacements - but I've got a VTL5C10.
Help! :icon_confused:
> I'm a little bit confused how to hook up the VTL5C10 or the LED/LDR combination.
Me too. It would help to collect the Schematic. And also, since it seems to have morphed from two duals to one quad, the associated pinouts.
TRY this:
(http://i.imgur.com/JrMvb.gif)
Not at ALL verified.
Hmm, no luck with that either :(
Thanks though! I'll try and hunt down a schematic.
Has anyone built this thing?
> no luck with that either
What happens? No sound?
You may have multiple problems.
Try a 5K resistor (or 10K, or jumper) at "cell". Does audio pass (constantly)?
If not, post voltages. http://www.diystompboxes.com/wiki/index.php?title=Debugging
Try a naked LED at "LED". It is supposed to be dark when silent, light when medium to loud signal is applied.
the cell should be connected at Row 1 point 13 and Row 4 point 7
LED at Row 1 point 7 and Row 2 point 7
Isn't the schematic in post 1 the schematic for the vero layout, except for the IC pin numbers?
Ronan,
To answer your question,
"Isn't the schematic in post 1 the schematic for the vero layout, except for the IC pin numbers?"
Yes it is. I've looked at this a few times trying to help but it's a bit more work when the schematic has the values listed, the layout has the component designations listed, and the schematic and the layout do not match due to the retrofit of a quad op amp from two dual op amps.
Quote from: Fender3D on November 24, 2012, 09:37:19 PM
the cell should be connected at Row 1 point 13 and Row 4 point 7
LED at Row 1 point 7 and Row 2 point 7
Hmm so, like this:
(http://i49.tinypic.com/35056s9.jpg)
That's how I've got it, so it must be something else... I'll keep troubleshooting :)
Quote from: armdnrdy on November 25, 2012, 01:26:57 AM
Ronan,
To answer your question,
"Isn't the schematic in post 1 the schematic for the vero layout, except for the IC pin numbers?"
Yes it is. I've looked at this a few times trying to help but it's a bit more work when the schematic has the values listed, the layout has the component designations listed, and the schematic and the layout do not match due to the retrofit of a quad op amp from two dual op amps.
Fair enough, I'm having the same problem. Can't relate the vero to the schem since there are no values for the vero. It then becomes a crossword puzzle that I don't need. Just wanted to confirm that was the correct schematic.
Next question is, Marcus, how did you know what value components to fit to the vero, since the values are not listed, or am I missing something?
If the LED is on all the time, with or without input signal, then the output is high (pin 7 of the LM358 in the schematic). The output state depends on the difference in voltages at pin 5 and pin 6. The voltage at pin 6 is controlled by the transistor, when the transistor is off, pin 6 should be close to 9V, and pin 7 should be low, turning the LED off. That is, with no input signal, pin 6 should be close to 9V, and pin 5 should be around 3V.
This is what I've been going off:
(http://i48.tinypic.com/2vj5teq.png)
http://diy-layout.com/67 (http://diy-layout.com/67)
Marcus, I think that vero layout has errors.
R12 looks correct, but R13 should connect from R12 to ground (row 7 to row 10 instead of 7 to 9). Then R11 has to somehow connect to the TL074 pin 5 to pin 7. I don't think this was ever verified.
Edit - I would start with those changes, and it might work, if not, let us know. If it does work, let us know too :)
Quote from: Ronan on November 25, 2012, 04:13:38 AM
Marcus, I think that vero layout has errors.
R12 looks correct, but R13 should connect from R12 to ground (row 7 to row 10 instead of 7 to 9). Then R11 has to somehow connect to the TL074 pin 5 to pin 7. I don't think this was ever verified.
Edit - I would start with those changes, and it might work, if not, let us know. If it does work, let us know too :)
I just made those changes with no luck :(
When I puck a resistor where the CELL should be, The LED stays on no matter what all the time.
Marcus,
Have you ever etched your own boards? If you search the net there is a PCB available that includes all of the relevant information.
Looking at your first post in this thread, I see that you've been trying to get this thing going since May 2012. That's quite a long time for a small, easy build such as this.
You just had two very knowledgeable people (PRR and Fender3D) roll through here trying to help you, and they couldn't get it with the information supplied.
A bit of advice: Sometimes when I get the information to a project, it will not be in the optimum format. First thing I do is fix that.
Let's say as in this project the info is all there but not consistent from schematic to layout to bill of materials. (BOM) What I would do is trace the circuit out adding the missing info, component designations (numbers) to the schematic. Print out the schematic and go through the layout penciling in the component designations as you go.
Google the data sheet for the TLO74 to get the proper pinout and use the available info to:
A. Verify the TLO74 vero build
B. Verify where the VTL5C10 goes in the circuit.
If you need any more help, there are many members of this site that are very generous with their time and would be glad to help you.
Marcus, if you can give us the voltages at all the pins of the TL074, we should be able to sus it out, or at least point you in the right direction.
Thanks Ian :) This one has been bugging me for a while! It'll be my 11th build when it works :icon_cool:
Here are the voltages with no input and with a Red LED and just a jumper for the CELL
Power Supply: 9.67v
TL074CN:
1: 4.44v
2: 4.43v
3: 4.39v
4: 8.88v
5: 6.71v
6: 0.01v
7: 8.01v
8: 4.46v
9: 4.44v
10: 4.44v
11: 0.01v
12: 2.21v
13: 4.44v
14: 4.44v
Here's a bad, blurry photo :icon_lol:
(http://i46.tinypic.com/15gvv60.jpg)
The voltages on pins 5, 6, 7 & 12 don't look right. The 8v on pin 7 is going to keep that led full on.
Is pin 6 going to ground via that toggle switch ? What happens when that's the other way.
I'd also expect the voltage on pin 12 to be closer to 4.4v
Given that pin 6 is at or near ground, then the voltages at pins 5 and 7 look OK to me.
The problem is that pin 6 is near ground, either through that switch, or because the transistor is fully turned on. If the transistor is the right type and in the correct orientation, then it must have 0.6 to 0.7V or more on the base to turn it on. With no input signal, the base should be close to ground via the 220K resistor (going from base to ground).
One question, does the board pass signal from input to output as it is, with a resistor in place of the VTL?
I finally found the BOM on that fancy website - sorry about that! Its under the BOM tab :icon_rolleyes:
Ok, so I'm running it exactly as the layout, except for these changes:
Quote from: Ronan on November 25, 2012, 04:13:38 AM
R12 looks correct, but R13 should connect from R12 to ground (row 7 to row 10 instead of 7 to 9). Then R11 has to somehow connect to the TL074 pin 5 to pin 7.
I have a normal Red LED and just a jumper where the CELL should go (you can see it in the pic I posted before)
Here goes...
Quote from: Pyr0 on November 26, 2012, 08:56:38 AM
Is pin 6 going to ground via that toggle switch ? What happens when that's the other way.
Pin 6 changes between 0.00v and 0.14v when you flick the switch.
Quote from: Ronan on November 27, 2012, 04:20:45 AM
The problem is that pin 6 is near ground, either through that switch, or because the transistor is fully turned on. If the transistor is the right type and in the correct orientation, then it must have 0.6 to 0.7V or more on the base to turn it on. With no input signal, the base should be close to ground via the 220K resistor (going from base to ground).
The transistor is the one listed on the BOM.
I'm not sure which is the 'base', but orientated as per the layout, the 3 legs read
Top: 0.01v
Middle: 3.15v
Bottom: 0.01v
Quote from: Ronan on November 27, 2012, 04:20:45 AM
One question, does the board pass signal from input to output as it is, with a resistor in place of the VTL?
Yep, with a LED and a Jumper, it passes audio fine.
??? ??? ???
Good to hear the rest of the circuit is working fine, passing audio.
The middle leg of the tranny is the base, it should have no voltage on it with no input signal from the guitar.
Even with a signal going in, it will be AC not DC.
R13 should no longer be connected to the base, so it would be worth trying to find out where that 3.15V is coming from, that is causing your problems at this stage. If you can't see or find anything obvious, it might be worth removing the transistor and then seeing if there is voltage at the base. If the voltage is gone, then try a new transistor, if the voltage is still there, you need to find out where it is coming from. If/when you remove the transistor, you should have around 9V at the upper leg (collector), 0V at the base, and 0V at the lower leg (emitter). That is, if all is well. If you don't get those readings, then let us know and we'll go from there.
Quote from: Ronan on November 28, 2012, 06:13:02 AM
Good to hear the rest of the circuit is working fine, passing audio.
The middle leg of the tranny is the base, it should have no voltage on it with no input signal from the guitar.
Even with a signal going in, it will be AC not DC.
R13 should no longer be connected to the base, so it would be worth trying to find out where that 3.15V is coming from, that is causing your problems at this stage. If you can't see or find anything obvious, it might be worth removing the transistor and then seeing if there is voltage at the base. If the voltage is gone, then try a new transistor, if the voltage is still there, you need to find out where it is coming from. If/when you remove the transistor, you should have around 9V at the upper leg (collector), 0V at the base, and 0V at the lower leg (emitter). That is, if all is well. If you don't get those readings, then let us know and we'll go from there.
I've just taken the transistor (2N3904) out and replaced it with a socket.
I have a red LED and a jumper in where the VTL5C10 is supposed to go.
With the transistor out, the LED stays ON.
Here are the readings at each hole of the socket with no input:
collector - top leg: 0.02v & 1.41v (switch)
base - middle leg: 0.02v
emitter - bottom leg: 0.02v
R13 (1M) is no going from "2 Along, 7 Down" to "2 Along, 10 Down" , which puts it from the 5th leg of the IC and at the bottom leg (emitter) of the transistor.
Thanks again for your help!
What you have done is good. Looks like the R11 is causing the LED to be permanently on, because it is pulling pin 6 of the IC to ground, and it shouldn't be in that position on the vero - it is another mistake in the layout. Hopefully the last fix is - remove R11 (1 Meg resistor), it needs to be soldered between pins 5 and 7 on the IC. There may not be room on top of the pcb, if not, maybe solder it underneath on the copper side. Then the LED should be off with no signal, and anywhere between dimly to brightly lit with a guitar signal, and if so, try fitting the VTL5C10 and while praying to the pedal gods, apply power and a guitar signal and see what happens.
I've moved R11 so that it now goes from "6across-7down" to "6across-9down" which was a trace cut, but I put it through and bent it and soldered it on the IC side :icon_wink:
Still... the LED stays ON...
I'm wondering if I might need another trace cut there somewhere?
Anyway, it's late - I'm off to bed to ponder this layout and to pray to the pedal gods! haha
I've just drawn up how my build looks right now - in its "not working" state haha
(http://img6.imageshack.us/img6/6030/dod230gate.png)
Hi, I got a notice that my layout isn't working. I object to that "opinion"! :icon_cool:
(http://diy-layout.com/diyl/67/render)
DOD 230 Noise Gate (http://diy-layout.com/67)
I forgot to update the description after building one: it works, but it's not very good ... It closes too late and abrupt, not anything like the iSP Decimator, which I cloned right after the DOD. I also own a original Coron Noise Gate (MXR Clone) which behaves the same, so I guess that's common with these type of gates.
IIRC, I still have a complete print somewhere ... Do you want me to check something?
On the vero there is R13, a 1M resistor, connected to Q1's base. This does not match the schematic.
On the vero, R11, a 1M resistor connects pin 6 to gnd, does not match the schematic.
There is no 1M resistor between pins 5 and 7 of the TL074, feedback that locks the gate in or out.
There is doubt that a TL074 will deliver the output to ground that an LM358 can, which may or may not cause latch-up when power is switched on. I'm wondering if this is what is stopping Marcus' circuit now.
If the vero is correct then the schematic is wrong. Or otherwise I'm wrong. Any of these is a possibility :)
Marcus, I'll have a good look at this in the aussie morning, go from there.
I can't see any problems with your layout Marcus. As far as I can see it should work. Can you measure the following resistances with the IC out and power disconnected?
pwr to gnd, should be around 44k
pin5 to pwr, should be around 500k
pin5 to gnd, should be around 500k
pin6 to pwr, should be around 220k
pin6 to gnd, should be around 264k
pin7 to pwr, should be around 1.5 meg ohms
Here's a schem showing TL074 pinout and component designators:
(https://dl.dropbox.com/u/61170900/DOD%20230%20noise%20gate%203.PNG)
I breadboarded the opamp section driving the LED using a TL072, it worked fine.
Now that R11 and R13 are in the right places, could you measure the voltages on pins 5, 6 and 7 again, with the IC fitted, power on, and no guitar signal (as in guitar plugged in and guitar volume turned to zero - or just short the input socket).
Quote from: Ronan on December 14, 2012, 01:31:34 AM
I can't see any problems with your layout Marcus. As far as I can see it should work. Can you measure the following resistances with the IC out and power disconnected?
pwr to gnd, should be around 44k
pin5 to pwr, should be around 500k
pin5 to gnd, should be around 500k
pin6 to pwr, should be around 220k
pin6 to gnd, should be around 264k
pin7 to pwr, should be around 1.5 meg ohms
IC out, power unplugged, LED and Jumper in:
pwr to gnd, should be around 44k =
42.2kpin5 to pwr, should be around 500k =
153kpin5 to gnd, should be around 500k =
182kpin6 to pwr, should be around 220k =
no reading...pin6 to gnd, should be around 264k =
no reading...pin7 to pwr, should be around 1.5 meg ohms =
1.14MSomething is weird there...
Quote from: Ronan on December 14, 2012, 01:31:34 AM
I breadboarded the opamp section driving the LED using a TL072, it worked fine.
Now that R11 and R13 are in the right places, could you measure the voltages on pins 5, 6 and 7 again, with the IC fitted, power on, and no guitar signal (as in guitar plugged in and guitar volume turned to zero - or just short the input socket).
Pin 5 = 6.70v
Pin 6 = 0.04v (1.43v with switch flicked)
Pin 7 = 8.00v (7.87v with switch flicked)
All looks good except the 220k resistor R5 appears to be not connecting pin 6 to pin 4 of the IC. With the IC out, and no power, you should be able to measure 220k between pins 4 and 6. Until that happens, the circuit will not work.
pin5 to pwr, should be around 500k = 153k
pin5 to gnd, should be around 500k = 182k
Those measurements are fine if the switch was closed, sorry, I didn't specify the switch to be open...
R5 is somehow not connected at both ends, and that appears to be the problem. When pin 6 goes high voltage (maybe 8V give or take), then the gate will close. While ever pin 6 is below a few volts, the gate will always be open. R5 is needed to pull pin 6 high when there is no guitar signal, to close the gate.
(https://dl.dropbox.com/u/22593339/Emoticons%20and%20Emoji/dance.gif) It works! (https://dl.dropbox.com/u/22593339/Emoticons%20and%20Emoji/dance.gif)
I traced back to R5 and found that it indeed wasn't going from Pin 6 to Pin 5 - fixed that, and not it's going!
My VCL5C10 has broken off a couple of legs because it was in and out of the socket so much... I have ordered a new one, but I found a VTL5C4/2 laying around and that seems to work fine.
(https://dl.dropbox.com/u/22593339/Emoticons%20and%20Emoji/thankyousign.gif)
Thanks so much for all your help Ian and others, and thanks for making the layout Harold - hopefully this thread helps out others with this one :)
Now, the next thing is that it adds a bit of volume and a slight amount of distorted fuzz compared to the bypassed sound.
It's kinda like a "boost/fuzz/gate" pedal at the moment.
Is there a way to tame the volume boost and remove the slight distortion?
Ian,
You deserve an award for perseverance!
mwynwood,
You should present the award!
Congrats to both!
Thanks Larry, Marcus is very tenacious, I think
he should get an award :)
Quote from: mwynwood on December 16, 2012, 05:32:54 AM
Now, the next thing is that it adds a bit of volume and a slight amount of distorted fuzz compared to the bypassed sound.
It's kinda like a "boost/fuzz/gate" pedal at the moment.
Is there a way to tame the volume boost and remove the slight distortion?
If you increase R14 (10k) to 22k or 33k (just guessing) it should bring the gain back to unity. I'm not sure exactly what size to choose, it will have to be trial and error. Or temporarily fit a 25k or 50k pot in series with the 10k (R14) and find what value you need.
Be careful, if you fit a pot without the series 10k resistor, and turn the pot to minimum resistance, it will probably burn out the VTL5C4/2, and maybe damage the TL074. BTW, R14 will be different for different types of optocoupler, so if you swap out the VTL5C4 for VTL5C10 at a later date, you will probably have to readjust R14 for unity gain.
Quote from: Ronan on December 17, 2012, 01:49:51 AM
Thanks Larry, Marcus is very tenacious, I think he should get an award :)
Quote from: mwynwood on December 16, 2012, 05:32:54 AM
Now, the next thing is that it adds a bit of volume and a slight amount of distorted fuzz compared to the bypassed sound.
It's kinda like a "boost/fuzz/gate" pedal at the moment.
Is there a way to tame the volume boost and remove the slight distortion?
If you increase R14 (10k) to 22k or 33k (just guessing) it should bring the gain back to unity. I'm not sure exactly what size to choose, it will have to be trial and error. Or temporarily fit a 25k or 50k pot in series with the 10k (R14) and find what value you need.
Be careful, if you fit a pot without the series 10k resistor, and turn the pot to minimum resistance, it will probably burn out the VTL5C4/2, and maybe damage the TL074. BTW, R14 will be different for different types of optocoupler, so if you swap out the VTL5C4 for VTL5C10 at a later date, you will probably have to readjust R14 for unity gain.
Thanks!
An 180k resistor in series with R14 brings it back to about the same volume when bypassed with the VTL5C10 - I guess this means I can replace R14 with a 190k resistor.
The only thing now is a slight distortion/fuzz/farty/clicky noise that is always there.
Have a listen here: https://soundcloud.com/mwynwood/dod-230-noise-gate-problem (https://soundcloud.com/mwynwood/dod-230-noise-gate-problem)
This noise happens no matter how the switch is set, and obviously disappears when the whole effect is bypassed.
Marcus, can you measure the voltages on all the pins of the TL074 again (with the switch open, and a guitar connected with the volume turned to zero)? Just wondering, was there ever a time when this noise was not present? The sound clip is interesting...it seems to have a slow close and opening time, might be a good thing, I don't know, but there would be ways to modify that if required. That noise definitely should not be there. If you have a really strong magnifying glass it would be worth checking for dry solder joints, where it looks like the solder is not flowing onto a component leg freely.