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DIY Stompboxes => Building your own stompbox => Topic started by: pgosselin on January 14, 2018, 04:50:04 PM

Title: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 14, 2018, 04:50:04 PM
Hi all,

I've been a long-time lurker here, but have finally felt the need to join because, well, I'm stumped.

I've been building a Veroboard clone of a Boss CE-2 chorus pedal based off of this plan:

http://tagboardeffects.blogspot.com/2014/06/boss-ce-2.html (http://tagboardeffects.blogspot.com/2014/06/boss-ce-2.html)

I've been building the third one down the page, the one without the daughterboard or the Madbean depth mod. I simply want the original CE-2.
Unfortunately, I made a horrible error. Two of my jumpers got pinched together underneath the IC4 socket. When I plugged it in, the 33 ohm resistor connected to the 9v supply fried (never had a part burn up on me before). Before I fried another resistor, I traced the 9v portion of the circuit to see where it had inadvertently connected to ground causing the dead resistor. That's when I found the jumper issue. I have repaired it and replaced the fried resistor.

Before I plugged it in again, I double checked the placement of all my parts. I did find one additional error. The 10K resistor (next to the 33 ohm one I fried) was not connected to the ground strip, but was connected to the strip below it. I have also fixed that error.

Now when I plug in the pedal for testing, I get a signal through the bypass. But when I engage the pedal, I get nothing. Not even a weak or distorted signal.

The LED is on and I have checked to see that the board is getting power. I am reading 9.41v where the 9v connects to the board.

I have even tried to audio probe the board and while the audio probe works in bypass, I get no signal before the board (not even at the hot input tab on the input jack, where usually I can get a signal) or on the board. I CAN get a signal through by touching the output tabs of the foot switch and the output jack.

The input tabs on the input jack and foot switch appear to be okay. I can get continuity from the hot tab of the input jack all the way to the input on the circuit board. So the wiring looks good that far. So I can't figure out why I can't pass the audio signal through.

I am at a loss as to what I did wrong.

Did my earlier problem also fried the IC chips? If so which ones?

Here are the readings I get from the pins of the IC chips:

IC#1 (JRC4558D)
1. 8.68v
2. 8.64v
3. 8.60v
4. 0
5. 8.60v
6. 8.68v
7. 8.68v
8. 8.60v

IC#2 (TL022CP)
1. 9.16v
2. 8.61v
3. 8.73v
4. 9.26v
5. 8.62v
6. 8.72v
7. 8.72v
8. 9.26v

IC#3 (MN3007)
1. 9.26v
2. 9.05v
3. 7.81v
4. 9.04v
5. 9.26v
6. 9.05v
7. 9.21v
8. 9.21v

IC#4 (MN3101)
1. 9.26v
2. 9.05v
3. 9.26v
4. 9.05v
5. 9.04v
6. 8.95v
7. 9.13v
8. 9.26v

And here are the readings from the 5 transistors (2N5088)

Q1
E 7.33v
B 7.62v
C 9.26v

Q2
E 7.81v
B 8.32v
C 9.26v

Q3
E 7.48v
B 7.84v
C 9.26v

Q4
E 9.26v
B 8.60v
C 8.62v

Q5
E 9.25v
B 8.47v
C 9.26v

Here is a link to a gallery with photos of the front and back of my Veroboard project as well as the schematic from Tonepad:
http://s1134.photobucket.com/user/pdgosselin/library/Boss%20CE-2 (http://s1134.photobucket.com/user/pdgosselin/library/Boss%20CE-2)

I have also used tone pad's parts list. If you need to access it, you can find it here:
http://www.tonepad.com/getFileInfo.asp?id=101 (http://www.tonepad.com/getFileInfo.asp?id=101)

I would appreciate any helping insights that the much smarter people than me on this board can supply. (While I do enjoy these projects, I often feel like I am swimming in water over my head.)

And if you do see additional errors with my work, by all means, let me know.

Thanks in advance for any help and advice.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 14, 2018, 05:09:32 PM
You are missing 0V on ICs 2, 3 & 4.
Resolder the outlined joint under IC4 and check the voltages again.


(https://s10.postimg.org/v5np51rhh/CE-2_Sod1.jpg) (https://postimg.org/image/v5np51rhh/)

Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 14, 2018, 06:00:03 PM
Slowpoke,

Thanks so much for the quick reply.

Great eyes noticing the poor solder joint. I have repaired it. But I am afraid to take readings at the moment

When I plugged in the circuit board to take readings, I smelled something beginning to burn. I immediately unplugged the board. Upon inspection, it looks like that same 33 ohm resistor is starting to burn up. I checked continuity between those two long traces under IC1 and IC4 and they are again connected somewhere.I've got a short circuit in there I need to find.

Dang it, I thought I had solved that.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 14, 2018, 06:48:37 PM
The component that your are using as D3 is most likely a zero ohm resistor (a link). Yes, zero ohm links do exist.
Replace it with a diode and the short that you are chasing should disappear.


(https://s10.postimg.org/wv1uapy85/CE-2_Comp1.jpg) (https://postimg.org/image/wv1uapy85/)

I didn't edit the image properly hence the excessive black borders...oops.

Oh yes, Welcome to the forum.

Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 14, 2018, 07:01:53 PM
No worries about the black border, Slowpoke. I'm just glad to have the help.

You are correct, that is a jumper. As I researched this pedal, a lot of builders said that 12v zener diode was unnecessary if you had a regulated power supply. The diode is supposedly a relic from the days when Boss used a 12v unregulated wall wart.

But maybe the layouts of the people omitting it differed a little from this one?

Fortunately, I ordered 12v zener diode with the rest of my parts just in case. I'll swap the parts and see if that makes a difference.

Thanks again for taking a look at my post.
Title: Re: Help needed with Boss CE-2 clone project
Post by: thermionix on January 14, 2018, 08:21:22 PM
I can't follow a vero layout nearly as well as a schematic, but there's a good chance that omitting that zener means just that, use nothing in its place rather than a jumper.  I would try snipping that out, see what happens.  If you want to replace it later, just use some component lead clipping (free!).
Title: Re: Help needed with Boss CE-2 clone project
Post by: duck_arse on January 15, 2018, 09:44:27 AM
measure the resistance between pin 8 and 4 on the opamps, then, like therm says, snip that zero link, and measure resistance again. and if you are worried about voltsing up the IC's, just pull them from the sockets before you power on, and do voltage measures on the empty pins.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 15, 2018, 06:32:26 PM
Thanks for the help Slowpoke101, Thermionix and duck_arse. I'm getting closer.

I went ahead and snipped the jumper and soldered in the zener diode. I had already done it last night before Thermionix and duck_arse replied. (But I came to the same conclusion as you all: if I was going to omit it, I didn't need to add the jumper.) As things stand now I have the diode in place so I'm sticking with that for now.

The results:
-- I am no longer cooking that poor little 33 ohm resistor, but the effect is still not working right.
--However, the good news is that before, I couldn't get a signal through. Now I am getting a barely perceptible one through one through when I touch the audio probe to the hot lug of the input jack and to the foot switch lugs. It's barely there, but it's there. At random, I touched the audio probe elsewhere on the circuitboard and got a regular level signal through. So that's progress.

If by looking at my IC chip and transistor readings you all can point me in the right direction to narrow my search for more errors, here's the NEW data:

IC#1 (JRC4558D)
1. 3.09v
2. 3.09v
3. 3.09v
4. 0
5. 3.09v
6. 3.09v
7. 3.09v
8. 9.18v

IC#2 (TL022CP)
1. 8.51v
2. 3.09v
3. 3.91v
4. 0
5. 3.09v
6. 6.37v
7. 3.16v
8. 9.18v

IC#3 (MN3007)
1. 9.19v
2. 4.71v
3. 2.45v
4. .614v
5. 0
6. 4.69v
7. 3.12v
8. 3.12v

IC#4 (MN3101)
1. 9.19v
2. 4.69v
3. 0
4. 4.71v
5. .224v
6. 8.38v
7. 2.51v
8. .614v

And here are the readings from the 5 transistors (2N5088)

Q1
E 2.31v
B 9.17v
C 9.19v

Q2
E 2.45v
B 3v
C 9.19v

Q3
E 3.09v
B 2.98v
C 9.19v

Q4
E 0
B .702v
C 4.06v

Q5
E 1.112v
B 3.07v
C 9.19v

Oh and, duck_arse, I am gong to sound like a complete idiot, but how do i measure the resistance between pins 8 and 4 on op amps? Do I set my multimeter to ohms and then put a probe against each leg? Do I do it with power on or off? I would assume off.

Once again, everyone, thanks for all the help thus far. And since there appear to be so many Aussies helping me, just so you all know, the first song that plays when I audio probe is AC/DC's "You Shook Me All Night Long."  :D
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 15, 2018, 07:52:13 PM
You are making progress - no magic smoke being emitted.

Q1 - its base voltage is far too high. Should be about 4.9V - perhaps shorted to its collector.

You do have to adjust the trimmer. A good starting point is to measure pin 5 of IC1 and adjust the trimmer for 5V.
Once you have corrected the Q1 problem and adjusted the trimmer, try to see if you can get audio through the pedal.
You must have the "Vibe" switch closed. This will allow dry audio to pass. If you have dry audio - good and now onto the next problem.

IC2 (TL022) which is the LFO doesn't seem to be working - according to the voltages you posted. Have a good look for any shorts or solder bridges in that area. Make sure that you have the Rate pot correctly installed and that it actually works. Pin 1 of IC2 should go from nearly 0V and up to 8V. The speed at which it does this depends on the rate pot setting.

If all is working now you can move on to the correct setting of the trimmer. Set the "Vibe" switch to open and see if you have any audio passing through - if you do, set Rate to midrange and Depth to maximum then adjust the trimmer so that the audio you are hearing is not too distorted but is still being modified by the delay effect. Easy to do with an oscilloscope but fiddly to do by ear.

If you still have problems measure all the voltages again and let us know.

Now for that link that you used as D3. If you look at the Tonepad parts list there is no D3. It is actually listed as D7 (11V zener). If you look at Tonepad's schematic you will see that D7 is connected to the main power rail (9V) and to ground (0V). If you replace it with a link you effectively short out the incoming power and release the magic smoke. So it would have been better to have nothing installed in the D3 position. You don't really need to have the zener but it can save the MN3007 from frying if something does go wrong.

Good job on AC/DC. A great band.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 15, 2018, 10:04:37 PM
Holy cow, Slowpoke101. You can tell all that from my data! That will take me a few night to work through all of that.

Since I eliminated the vibe switch, I may have to wire one up temporarily.

Thanks for all the help!
Title: Re: Help needed with Boss CE-2 clone project
Post by: DIY Bass on January 16, 2018, 02:48:05 AM
Also, have you replaced that 33 ohm resistor since you last overheated it?  Even if you didn't smoke it I would be suspicious that it is no longer at the proper value.  At the very least check it but I would be replacing it if you haven't already.
Title: Re: Help needed with Boss CE-2 clone project
Post by: duck_arse on January 16, 2018, 09:04:48 AM
I'd like to look at your photos, but, well, botophucket. and scripts. and viva, whatever that is, eats my pc.

when measuring resistance, always power-off the circuit. the meter itself puts some known volts across its probes, and reads the result thru the resistor, so if you go adding stray volts here and there having the supply on, all your results will be wrong. I wanted the opamp pins cause I couldn't see the circuit, so opamp pins 8 and 4 [while the IC is still fitted, tho across the empty socket pins will show the same result] would have shown 0R while the link was there, and "some number larger than 0" once it was removed. the change in the reading was what I was driving towards.

and from your data - it's easy - your Vb connects to pin 5 of IC1, so we know that voltage. it also connects to the base of Q1 via 470k, so the base should be a little lower than the Vb at pin 5, whereas yours is sky high, close enough to the collector voltage as no matter. pointing to a short.

all those 3V09 voltages on IC1 should track the trimpot as you adjust it, once you've fixed the short.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 16, 2018, 10:30:40 AM
Quote from: DIY Bass on January 16, 2018, 02:48:05 AM
Also, have you replaced that 33 ohm resistor since you last overheated it?  Even if you didn't smoke it I would be suspicious that it is no longer at the proper value.  At the very least check it but I would be replacing it if you haven't already.

Yes, I did. Even with minimal charring, I didn't trust it.

Thanks for double checking me, DIY Bass.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 16, 2018, 11:40:38 PM
Quote from: Slowpoke101 on January 15, 2018, 07:52:13 PM
You are making progress - no magic smoke being emitted.

Q1 - its base voltage is far too high. Should be about 4.9V - perhaps shorted to its collector.

You do have to adjust the trimmer. A good starting point is to measure pin 5 of IC1 and adjust the trimmer for 5V.
Once you have corrected the Q1 problem and adjusted the trimmer, try to see if you can get audio through the pedal.
You must have the "Vibe" switch closed. This will allow dry audio to pass. If you have dry audio - good and now onto the next problem.

IC2 (TL022) which is the LFO doesn't seem to be working - according to the voltages you posted. Have a good look for any shorts or solder bridges in that area. Make sure that you have the Rate pot correctly installed and that it actually works. Pin 1 of IC2 should go from nearly 0V and up to 8V. The speed at which it does this depends on the rate pot setting.

If all is working now you can move on to the correct setting of the trimmer. Set the "Vibe" switch to open and see if you have any audio passing through - if you do, set Rate to midrange and Depth to maximum then adjust the trimmer so that the audio you are hearing is not too distorted but is still being modified by the delay effect. Easy to do with an oscilloscope but fiddly to do by ear.

If you still have problems measure all the voltages again and let us know.

Now for that link that you used as D3. If you look at the Tonepad parts list there is no D3. It is actually listed as D7 (11V zener). If you look at Tonepad's schematic you will see that D7 is connected to the main power rail (9V) and to ground (0V). If you replace it with a link you effectively short out the incoming power and release the magic smoke. So it would have been better to have nothing installed in the D3 position. You don't really need to have the zener but it can save the MN3007 from frying if something does go wrong.

Good job on AC/DC. A great band.

Slowpoke101,

Well, I scraped between the copper strips  near Q1 and there must have been a short I couldn't see with my magnifying glass. I got the  base voltage down significantly.  It was reading in the high 3s before I adjusted the trimmer to as close to 5 as I could get it. Now, Q1 reads as follows:

E = 4.01-4.13
B = 4.80-4.97
C = 9.11-9.15

I can't seem to get a steady voltage on Q1 or the trimmer, They kind of dance around between the numbers above. Same is true of the trimmer, it's dancing between 4.89 and 5.03. Is that normal?

I plugged in the guitar and tried to get a signal through, but no dice. Nothing's getting through.

Any thoughts?

Too soon to move onto IC2.

Thanks again for the help

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 17, 2018, 02:49:51 AM
Progress. This is good. At least the voltages on Q1 are now correct. Veroboard can be a pain for hiding shorts and broken traces. As time consuming as it is, testing each track for continuity and adjacent tracks for shorts can find problems faster than visual inspection.
From a prior post of yours I note that you have an audio probe (or something that can be used as one). You will need it shortly.

From the solder side picture of your board the soldering around the IC1 area looks as if it could be a bit better. Pin 1 of IC1 does not seem to be soldered properly and some adjacent solder joints look to be almost touching. Go over the area and make sure that it as all OK.

You don't need to install a "Vibe" switch - The original CE-2 didn't have one and the circuit works fine without it. Just install an insulated wire link from "Vibe Sw1" to "Vibe Sw2". Now check to see if dry audio passes through the effect. If it does - good, then proceed with the rest of the troubleshooting. If no audio passes test what audio signal is present on Pin 2 of IC1 and then Pin 1 of IC1. Both pins should have audio on them. Then test for audio on Pin 6 and Pin 7 of IC1, again audio should be present.
Let us know what the results are.

The dancing voltage from the trimmer...This may actually be good news (in a way). See if the speed that the voltage varies at  relates to the setting of the Rate and Depth pots. If it does vary then the LFO may be working.

The reason why we like people to post their voltage readings is that the voltages can tell the story of what is possibly wrong. Along with a schematic and some pictures of the board it becomes a lot easier to help diagnose what the problem is. It can be a lot of fun to work out what is going wrong. It's even better when the problems are resolved and someone's project is working and they are happy.


Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 17, 2018, 11:57:51 PM
Slowpoke101,

Here's where I am tonight.

1. I reworked all of the connections on IC1 and cleaned between tracks. Unfortunately, the copper has been lifting off my board right in that area, so I had to patch up a couple of the connections with some thin wire I have. I have checked continuity on each pin and it is good. I also used the multimeter to check to make sure there were no solder bridges between pins/tracks.

2. This is only the second Veroboard project I've done. Everything else has been either perfboard or circuit boards. My previous Veroboard project was Craig Anderton's phase shifter and it turned out great. So I thought I would try Veroboard again. This batch from Tayda does not seem to be as good as the last batch.

3. As for audio, I cannot get a guitar signal through. However, with my audio probe (which is connected to the headphone jack on an old MacBook), I can get audio through pins 2 and 6 of IC1. I cannot get audio through pins 1 and 7.

4. I also probed the input wire and the first capacitor and resistor, I am getting audio signals through on them, but very faintly. The audio on Pins 2 and 6 are a decent volume.

5. Why is it I can get audio signals through with my audio probe, but not with my guitar? That is very strange to me.

6. I have the vibe switch permanently closed. I realized I didn't need a switch last night. Per some instructions on the website where I got the Veroboard layout, the author said if one didn't want the vibe function, you could just move the 47k resistor at Vibe Switch 2 to the top row above IC1, bridging the cut. This effectively closes the switch.

This project is proving far more difficult than I expected.

Thanks again for all the help.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 18, 2018, 01:09:37 AM
You may not feel that you have but you have made progress.

The mod with moving the 47K resistor to the track above IC1 is elegantly simple. Better than running a wire link from one side of the board to the other.

Now, audio on pin 2 and 6 of IC1 but none on pin 3 and 7. An audio probe using the "headphone" socket on an old Mac...I assume that you mean the mic connection and that you are using the Mac as an amplifier. Make sure that your probe has a 0.1uF capacitor in series with the probe connection, otherwise any voltage that the Mac may send to a microphone may upset the circuit under test and vis versa. Audio on pin 2 means Q1 is working. Audio on pin 6 means that audio is coming out of pin 1 and making its way to pin 6. I suggest that you check for audio on the output lead were it connects to the board.

Buying quality Veroboard can be haphazard at best. The cheap boards do the job but really don't stay together when you rework any connections. Veroboard is (or was) a brand name product and the original board was of excellent quality but not cheap. A lot of the cheap stuff is OK but a lot it is not. No real control on what you get.

Once you get your audio probe installed with a 0.1uF coupling capacitor and found audio on pin 1 of IC1, see if there is any audio on pins 3 and 8 of IC3 (MN3007). Let us know how you go.


Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 18, 2018, 07:21:54 AM
Once again, thanks Slowpoke101.

I am already using an audio probe properly constructed with the .1 uF capacitor, I built it with a 1.8" male plug on the far end that goes into the headphones output jack on my MacBook (not the mic). That way, I can play music in iTunes and output it through the audio probe, touching the .1 uF cap to the various parts while the other wire attached the probe to the ground lug of the effect.

So the probing of pin 6 shows I have audio coming out of pin 1? Yet, I am unable to detect audio at pin 1 with the audio probe. Maybe I better test that area again and give it another look-see.

I will check for audio on the output lead wire where it connects to the board as well as pins 3 and 8 of IC3 tonight after work.

Thanks again,

Paul

Title: Re: Help needed with Boss CE-2 clone project
Post by: bluebunny on January 18, 2018, 08:16:02 AM
Erm, the audio probe is intended to be used the other way around: you plug it into an amplifier and probe your circuit listening for signs of the audio which you're delivering to the input jack (which might be a guitar or some other kind of sound generator).
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 18, 2018, 09:37:45 AM
Bluebunny,

Omg, I've been doing it backwards? Dang, even my backwards probe has helped me find some problems.

Definitely will be retesting tonight...the proper way.

Paul

Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 18, 2018, 01:39:35 PM
Hmm....

QuoteOmg, I've been doing it backwards?

Best laugh I've had all week  :icon_lol:. But it explains some of the results. Don't feel too embarrassed, we all started off as beginners. I should have picked up on that you were injecting signals earlier. Now why doesn't the effect amplify at Q1 when you inject a signal or connect a guitar to it. Here's why;



(https://s13.postimg.org/5a7kjnzo3/CE2_Input.jpg) (https://postimg.org/image/5a7kjnzo3/)

Change the two capacitors as shown. You appear to be using capacitors in the pF range and not the nF range. So a 47nF and a 470nF are the correct ones to use. Very little useful audio signal would make it through such small value caps.

Let us know how you go.


Title: Re: Help needed with Boss CE-2 clone project
Post by: bluebunny on January 18, 2018, 04:30:56 PM
Quote from: pgosselin on January 18, 2018, 09:37:45 AM
Omg, I've been doing it backwards?

You just invented the signal injector!   ;D

Don't sweat it - we've all done it.  My personal favourite is omitting to install the ICs, closely followed by plugging in my pedals back to front.   :icon_rolleyes:

And it gives us a chuckle, too.   :)

P.S. I get to give you your first "Like".  Now you've properly arrived, Paul!
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 18, 2018, 08:41:03 PM
Quote from: bluebunny on January 18, 2018, 04:30:56 PM
Quote from: pgosselin on January 18, 2018, 09:37:45 AM
Omg, I've been doing it backwards?

You just invented the signal injector!   ;D

Don't sweat it - we've all done it.  My personal favourite is omitting to install the ICs, closely followed by plugging in my pedals back to front.   :icon_rolleyes:

And it gives us a chuckle, too.   :)

P.S. I get to give you your first "Like".  Now you've properly arrived, Paul!

Hey, don't knock it. I fixed two pedals using the signal injector...just not this one.  :D
Title: Re: Help needed with Boss CE-2 clone project
Post by: PRR on January 18, 2018, 11:25:18 PM
> You just invented the signal injector!

Someone stole that invention over 100 years ago.

The original signal injector is a finger or screwdriver on the tube grid. Once we got AC lights, that should hum/buzz. I just saw the same trick in a 1960 electronics magazine, by guys with a benchful of fancier gear.

The tracer and injector are complementary. Just like a clogged vacuum cleaner hose. You look in the sucky end. Then you look in the end that blows. If not seen (or clogged with invisible electricity), you blow in the input and suck on the output. At least electrons don't leave a bad taste.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 19, 2018, 01:40:36 AM
We have guitar signal!  :D :D :D :D :D :D :D :D :D

Well, gents, those two caps were the problem. (Can't believe I stuck in the wrong values in not just one place, but two places side-by-side).

I replaced them and lo and behold, not only do we have a guitar signal going all the way through, we have lots of swirly goodness.

So I guess that means the last step is to set the trimmer. Any pointers on doing that without a scope? Where should I set the depth and rate knobs before adjusting the trimmer? I understand I am supposed to back off the trimmer from the place where it begins to distort? What kind of distortion are we talking about? Are we talking overdrive type distortion or that sort of artificial "ticking" sound that I hear a lot of people complaining about? When I was playing with it, I did hear that kind of distortion and was able to back it off from that and make it go away without altering the effect too much.

I can't thank everyone who commented enough for all the help, especially you, Slowpoke101. I'm not sure I would have figured it out without you all.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 19, 2018, 02:46:02 AM
You got it working  :icon_biggrin:. That is great news. You must be very pleased.

Now, adjusting the trimmer is not too difficult. You have already noted a ticking noise coming from the LFO (TL022) and that adjustment of the trimmer can help reduce it. Set the rate pot to about 3 o'clock (fairly fast but not flat out) and the depth to max (fully CW). Apply a signal (pluck a guitar string - 4th string will do) and turn the trimmer until the chorus effect drops out - note the position of the trimmer, then do the same again but turn the trimmer in the opposite direction - the chorus effect will return and then drop out again the further that you turn the trimmer - note that position. Set the trimmer midway between those two positions. This is a coarse initial set-up.

The distortion that you will hear sounds like the signal is breaking up - it is. Keep plucking a guitar string whilst slowly adjusting the trimmer. You will hear certain points that sound a little crackly - that's the distortion - and the ticking noise may become noticeable. Back off from that point and turn the trimmer the other way until you hear the crackle (and possibly the ticking noise) again. This is the same thing as what you've just done before but you are trying to get the adjustment finer and minimise the ticking noise without disturbing the chorus effect. Really the best thing to do is to adjust the trimmer so that you are happy with the signal. Once you are happy with it test it with the guitar's other strings and some chords played slowly - the adjustment point (for best audio) is frequency dependant.

If it sounds good to you it is most likely set correctly. Now to enjoy playing with your new effect.

If the ticking noise becomes annoying let us know as there is usually a way to deal with it.

Title: Re: Help needed with Boss CE-2 clone project
Post by: bluebunny on January 19, 2018, 03:33:06 AM
Initiation complete.  :icon_cool:
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 19, 2018, 10:51:17 PM
Hey guys, here are some photos of the nearly finished pedal.

Why nearly finished? I thought I had the trimmer perfectly adjusted. No distortion. Not ticking. So I mounted it in the case. As soon as I put the lid on and fire it up, all of a sudden I hear the faint ticking. If I pull the bottom panel off and go to adjust it, the ticking goes away. Any suggestions on how to eliminate the ticking? Would shielded wires on the input, output or rate or depth controls help?

Thanks,

Paul

(http://i1134.photobucket.com/albums/m612/pdgosselin/Boss%20CE-2/IMG_4024_zpsjf3waal1.jpg) (http://s1134.photobucket.com/user/pdgosselin/media/Boss%20CE-2/IMG_4024_zpsjf3waal1.jpg.html)

(http://i1134.photobucket.com/albums/m612/pdgosselin/Boss%20CE-2/IMG_4023_zpsbidutyju.jpg) (http://s1134.photobucket.com/user/pdgosselin/media/Boss%20CE-2/IMG_4023_zpsbidutyju.jpg.html)

(http://i1134.photobucket.com/albums/m612/pdgosselin/Boss%20CE-2/IMG_4025_zpsevvqjrfs.jpg) (http://s1134.photobucket.com/user/pdgosselin/media/Boss%20CE-2/IMG_4025_zpsevvqjrfs.jpg.html)

Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 20, 2018, 06:02:20 AM
My Zombie Chorus works fine, it gets ticking at extremely high setting but is not a big deal for me. Anyway, this is one of the reasons I included this CE-2 project (probably the modded version) and I don't wanna get any ticking issue this time!

I'm very interested in the solutions.

Edit:

I found this:
http://guitar-fx-layouts.42897.x6.nabble.com/boss-ce-2-ticking-td21858.html

(http://guitar-fx-layouts.42897.x6.nabble.com/file/n22205/Boss_CE2_with_mods_fjk.png)

"The mod is pretty simple if you want to add a separate voltage divider for the TL022.

(1) Remove link as shown.
(2) Add a 47uF cap to the upper right.
(3) Add two 10K resistors at bottom (gray).
"

I think that's it.
Not verified by me, but seems it is ok.

I still didn't compared well with the Sabrotone version, which has the 47uF, I don't see the two 10k resistors instead, but I guess the schematic around the TL022 seems a bit different.
On Sabrotone nobody talk about ticking issue. I probably gonna build that one, crossing my fingers. :P
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 20, 2018, 10:31:24 AM
Thanks, Elijah-Baley,

That looks easy enough to try. And if it doesn't work, I can always restore it back to the original circuit.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 20, 2018, 04:27:50 PM
In that fourm the guy solved the ticking issue, but got a pop when engage the effect. Weird.
Anyway, let us to know. ;)
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 20, 2018, 11:09:22 PM
Elijah-Baley,

I tried the mod tonight.

The pedal still works as before, but it does not get rid of the faint ticking. The ticking is definitely related to the rate knob since the ticking speed increases as the knob is turned.

Also, the revised illustration is deceptive where you add the 10K resistors. The 100n cap and the 1M resistor have to move from their original positions.

No pops whatsoever on the foot pedal.

So that means I am still looking for a way to reduce the ticking. It's only noticeable when I am not playing and volume is barely above the hiss of the amp. I can probably live with it, but the perfection in me wants to eliminate it if I can.

When adjusting the trimmer, I don't really get a lot of distortion (really only on one side) so there seems to be a decently wide area of the trimmer where the effect is strong and distortion free before the effect drops off on either side.

When I have the back off the pedal, it doesn't tick. It's only when I screw the back panel on. That makes me think it might be a shielding issue.

So, guys, are there any other strategies out there for knocking back the ticking noise of the LFO ?

Thanks,

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: DrAlx on January 21, 2018, 06:11:07 AM
Reducing ticking on that LFO.
1) Keep the rate pot wires as short as possible and as far from the audio path as possible. Worst ticking is at the highest rate setting because in that case the Rate2 wire is directly connected to the opamp output and sees the full square wave voltage swing and radiates it everywhere.
2) The bias voltage for the LFO should be set half way between the swing voltages of the square wave.  This may not be half the supply. On the lowest rate setting, measure the square wave voltage levels (on Rate3 pin), and then calculate the mid-point voltage. The schematic on Electrosmash shows a trimmer in the power supply section for setting the bias (which is labelled as 4.5v). Treat the 4.5v value as an approximation.  Its better to set it to the midpoint of the square wave.
3) There is an anti-tick mod used on some Boss pedals that involve smoothing  the square wave slightly. Mark Hammer has posted a reference on it.  It involves an extra cap and resistor. Look at the Tri-Vibe LFO as an example.

EDIT: I just looked again at the Electrosmash schematic and it seems the single trimmer sets both BBD bias and LFO bias. That is pretty horrible in my opinion.  Maybe the BBD bias and LFO bias are reasonably close to each other in that circuit.
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 21, 2018, 06:42:43 AM
Sorry to hear that, this is pretty disappointed.

Are you using the "original" layout, right? The anti-ticking mod is based on the other layout, but the schematic is pretty the same.

To understand better the position of the 10k read the schematic here:
http://www.madbeanpedals.com/projects/PorkBarrel/PorkBarrel_2015.pdf
The two 10k resistor should be R28 and R29.

Or better look also this:
http://www.tonepad.com/getFile.asp?id=101
Here you can see the two 10k resistors (R33 and R34), but this one includes even the 47uF, C20.

What is I get is that the Guitar FX layout version is based on the original schematic:
https://www.electrosmash.com/images/tech/ce-2/boss-ce-2-schematic-parts.png
Of course the JFET Switching section is exluded.
In the layout has been included some mods taken from Tonepad and Madbean's Pork Barrel schematic.

The layout with the anti-ticking mod I linked above is based on the Madbean's Pork Barrel schematic, I see the two 10k resistors but I can't found the 47uF.

This is the Sabrotone version: http://www.sabrotone.com/wp-content/uploads/2013/04/ChorusEnsemble2.gif
I know is a bad deal, but if you really can't fix your build you can try the Sabrotone's layout.
I wanna quote some comment in the Tonepad report of the CE-2.

«shileded input/output wires are a must! ie from jack to switch to pc to switch to output jack. without this i couldnt get mine to stop ticking.»

«The sound is nice. I had some ticking at first, even with shielded cable, but just by moving the pcb a bit and by using a piece of self-adhesive copper tape around the output jack solder, I removed it.»

«You have to make sure the IN wire is either shielded or away from the LFO section, or you will get some slight ticking.»

«You MUST use shielded cable between input/output from jacks to switch, and between input/output from switch to board, with only one end of the shield in each cable connected to ground!!! Otherwise, you will get LFO ticking! Without it, there was ticking all over the place, once I used shielded cable, it was TOTALLY silent, wich means that the tonepad PCB works PERFECTLY!!»

«When I boxed the thing there was a ticking noise at first, i t disappeared when I turned rotated the board 180 degrees.»
Title: Re: Help needed with Boss CE-2 clone project
Post by: DrAlx on January 21, 2018, 07:38:31 AM
So the two extra resistors in the mod listed by Elijah are just to give separate LFO bias. His diagram looks OK. Remove the long link so the LFO is not sharing bias with the audio/BBD. Then make a voltage divider from two resistors. Common point of the resistors is pin 5 if the IC. That is the LFO bias point. The other ends of the resistors go to pin 8 (IC positive supply) and to ground. You should not need to move the 1 meg or 100nF.
If you still get ticking using two 10k resistors, measure the square wave voltage at Rate 3 and see if the voltage swing is symmetrical about the bias level. In a similar LFO to this using an LM324 I found that i needed a higher bias voltage so used 10k going to supply and 12k to ground.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 21, 2018, 08:59:15 AM
I'm going to try shielding the wires and the output jack first. Since the board stops ticking once I have the back off the pedal and the board is outside of the case, that makes me think it's things being crammed into close proximity inside the case that is making it tick. It's a tight fit inside my 125B enclosure.
I don't have a scope, so I can't check square waves, etc.

I originally chose the Guitar fx layout vs the Sabrotone one because it looked like it would be a better fit inside the case. Now I'm wondering if I should have just ponied up the $16 for the tone pad circuit board. But even they seem to have ticking issues.

Oh, well, it's the journey not the destination, right? That's why we do the diy stuff in the first place. The important thing is the pedal is working. Now, I'm just refining to make it work better.

Thanks,

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 21, 2018, 01:32:32 PM
The main issue with all these LFOs is that they generate a squarewave signal. The trick to reducing the switching noise is to slightly modify the waveshape. The following picture is a partial layout of the tagboard CE2 clone with the mods included. The modification involves installing the two 10K resistors, moving a 47uF cap (and a few other parts)but the main mod is to do with IC2. A 1nF capacitor and a 100K resistor.

(https://s14.postimg.org/7y389lcb1/Boss_CE2_TBE_LFOmod.png) (https://postimg.org/image/7y389lcb1/)

Try it and see if it helps.

Just for interest's sake. The Sabro layout also ticks and the Tonepad layout also ticks (but not badly). The 100K resistor and the 1nF capacitor fixed them perfectly. Any effect that uses this style of LFO can and usually does tick to some extent.

I did send you a PM (personal message) yesterday with the picture but I was having access issues so it may not have been received.

Good luck.
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 21, 2018, 04:25:15 PM
Fine. I'm really curious about this mod.
The position of the 100k resistor is really bad. ::) I just watched quickly, I can't imagine a better position, now.

Could this 1nF-100k trick work even on Sabrotone layout?
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 21, 2018, 04:43:32 PM
The position of the 100K resistor is painful. I put the layout together rather quickly and I couldn't see an easy way of positioning it other than under the board.
The modification is based from a post by Mark Hammer. I usually put it in whenever I build something that uses that type of LFO.
It does work on the Sabrotone (?) layout - proven by forum member "ponce" late last year. Solved his ticking problem immediately.
Boss uses the mod as well in some of their older effects, eg: CE-3 Chorus. However Boss use a 10nF cap and not a 1nF cap. It doesn't really matter what value cap you use as long as it falls between 1nF and 18nF. Too small and the wave-shaping is insufficient and too high the wave-shaping becomes excessive and causes other fun issues.

You still need to use shielded cables for the input and output connections and be careful with internal cable layout - don't run the rate pot's cables directly over the input stages, etc. The cables still do radiate so care is required.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 21, 2018, 07:25:22 PM
Quote from: Slowpoke101 on January 21, 2018, 01:32:32 PM
I did send you a PM (personal message) yesterday with the picture but I was having access issues so it may not have been received.

Slowpoke101, I just looked. It made it through, but it got caught in my spam folder.  Thanks taking the time to do it!

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on January 21, 2018, 07:39:50 PM
Quote from: Slowpoke101 on January 21, 2018, 04:43:32 PM
You still need to use shielded cables for the input and output connections and be careful with internal cable layout - don't run the rate pot's cables directly over the input stages, etc. The cables still do radiate so care is required.

Unfortunately, I put the rate pot right above the output jack. I may have to shield all three of those wires, as well.

I'm going to do this in three stages. 1. shield the input/output wires. 2 shield the rate pot wires. 3. Make Slowpoke101's board mods. I'm going to test at each stage to see at what point the ticking goes away.

Fingers crossed.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 22, 2018, 03:46:15 AM
Quote from: Slowpoke101 on January 21, 2018, 04:43:32 PM
[...]
It does work on the Sabrotone (?) layout - proven by forum member "ponce" late last year. Solved his ticking problem immediately.

Do you know if the Sabrotone layout with the Mark Hammers's anti-ticking mod is posted somewhere?
Else, I guess I can mod it by myself.

When I said that the schematic around the TL022 in the Sabrotone was different frome the Guitar FX layout, it was because the pin connection are different, but their functions are the same. I don't know if I am clear, but it's nothing you still don't know, guys. :)

Quote from: Slowpoke101 on January 21, 2018, 04:43:32 PM
Boss uses the mod as well in some of their older effects, eg: CE-3 Chorus. However Boss use a 10nF cap and not a 1nF cap. It doesn't really matter what value cap you use as long as it falls between 1nF and 18nF. Too small and the wave-shaping is insufficient and too high the wave-shaping becomes excessive and causes other fun issues.

Actually, I was wondering however the Boss pedal, doesn't tick? At least I guess it doesn't tick. ???
Do that mod cause some changing in the sound? ???

Quote from: Slowpoke101 on January 21, 2018, 04:43:32 PM
You still need to use shielded cables for the input and output connections and be careful with internal cable layout - don't run the rate pot's cables directly over the input stages, etc. The cables still do radiate so care is required.

I'm not sure what do you mean. Maybe we should try to keep the rate pot wires away from other wires? Or what?

I tried to draw the Sabrotone Layout.
Tell me if there's any mistake.


(https://s18.postimg.org/f65utyw4l/Chorus_Ensemble2_-_Anti_Ticking_Mod.gif) (https://postimg.org/image/f65utyw4l/)
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 22, 2018, 07:08:38 AM
I never found a modified Sabrotone layout with the anti-tick mod. I helped ponce modify his board by sending him highly detailed step by step procedures. I can't find those details at the moment but it is not terribly difficult to do. Basically the capacitor is connected to IC2 pins 6 & 7. Pin 6 is isolated from pin 3 (which is connected to the Vref 4.5V rail set by R33 & R34). The resistor is then connected between pins 3 & 6. The end of R31 which was connected to pin 6 now has to be connected to pin 3 (Vref).

Please note: I specified an incorrect lower value for the capacitor. It should be no lower than 10nF and not higher than 39nF.

The Boss CE-2 pedal doesn't have a noticeable ticking problem due to the actual layout used and some good power filtering. However as the pedal ages guess what they start to do? Recap the pedal and it's usually back to normal.

The mod does not change the sound of the pedal in any noticeable way. All the LFO really does is wobble the clock rate slightly which gives the chorus effect.

Routing the cables within the enclosure can cause trouble. The rate pot cables are the most annoying as there is a fair amount of voltage changes carried by the cables. Theses voltages are essentially squarewave (even after the mod) which has quite significant transition noise at the leading and trailing edges of the waveform. This noise is referred to as "ringing" and is quite rich in harmonics. All of this can be picked up (received) by the effect's input amp or input & output cables. Shielded cable is recommended for the input and output cables. There is no reason why not to use shielded cable on the rate and depth pots other than it becomes cumbersome as the cable can be quite thick.

I've had a quick look at your redo of the Sabrotone layout. Very well done. I haven't checked it for any errors yet. That will be done in the morning. Quite late here at the moment.
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on January 22, 2018, 09:47:26 AM
Thanks for all these info.

I hope you can check my modded layout, though it's not so urgent for me, after your last explanation I have some doubts about my drawn.

Anyway I found a schematic of the CE-3, could be useful, I need it. ;)

I'm looking at the two 10k resistors: R46 and R50. Then the resistor R51 100k and the cap C27, it's a 47nF, I think. Are these our anti-ticking guys? :D
Title: Re: Help needed with Boss CE-2 clone project
Post by: Slowpoke101 on January 22, 2018, 02:51:37 PM
A partial circuit for reference;

(https://s14.postimg.org/c467dard9/BOSSCE3_LFO.jpg) (https://postimg.org/image/c467dard9/)

R46 and R50 (both 10K) make up the 4.5V Vref for the LFO. C27 (47uF) filters the Vref.

R51 (100K) and C29 (10nF) make up the anti-tick mod.

I will have a look at your modified Sabrotone layout shortly.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on February 01, 2018, 09:03:48 PM
Hi everyone,

Sorry it has taken me so long to post about my progress on making the ticking stop in my pedal. As I was desoldering the wires to my foot switch to replace them with shielded ones, the epoxy surrounding one of the lugs on the switch got too hot and I destroyed the switch (never had that happen before). I had to order some new switches and it has taken me over a week to get them.

At any rate, the switches arrived and tonight I wired up a new one with shielded input and output wires going from the input and outputs to the switch and from the switch to the board. The result? The ticking is completely gone. Shielding those wires made the difference.

I did not have to shield the wires going to the rate pot or make Slowpoke101's mod. Although, I am keeping copies of that mod because I might need to make it someday as the caps age. Or if I build this circuit again (highly likely), I'll just incorporate it from the beginning.

Thank you to everyone who helped me get this pedal up and running. I couldn't be happier with it. I've never had a chorus pedal before and I believe this may be my favorite effect now.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on February 02, 2018, 06:54:13 AM
Great! I'm glad to hear that.
Where do you find the shielded wires? Can you give a link or show the picture of this kind of wire? I never used it, and I'm curious.
Title: Re: Help needed with Boss CE-2 clone project
Post by: pgosselin on February 02, 2018, 08:58:05 AM
Quote from: Elijah-Baley on February 02, 2018, 06:54:13 AM
Great! I'm glad to hear that.
Where do you find the shielded wires? Can you give a link or show the picture of this kind of wire? I never used it, and I'm curious.

I picked up a spool of this very thin braided cable at Radio Shack about 30 years ago to connect the endpin jack on an acoustic guitar to the onboard preamp I built for the piezo-electric transducer pickup. Since Radio Shack is pretty much out of business, I doubt you could find it today.  Following are pictures of it so you can get a sense of scale. It is constructed very much like guitar cable. There is an inner core surrounded by an insulation sleeve, then surrounding that is braided wire and then the whole thing is covered in some kind of flexible plastic. What you do is you use the inner core for your signal wiring, but when you strip the outer casing, you carefully separate and twist all of the braided wires together then connect them to ground. The grounding wires surrounding the signal wires electrically shield them from everything else in the case. Your aluminum case, when connected to ground is one great big shield. So you're essentially shielding again inside the case.

(http://i1134.photobucket.com/albums/m612/pdgosselin/Boss%20CE-2/IMG_4031_zpso8ev79h0.jpg) (http://s1134.photobucket.com/user/pdgosselin/media/Boss%20CE-2/IMG_4031_zpso8ev79h0.jpg.html)

(http://i1134.photobucket.com/albums/m612/pdgosselin/Boss%20CE-2/IMG_4030_zpsbtrbooce.jpg) (http://s1134.photobucket.com/user/pdgosselin/media/Boss%20CE-2/IMG_4030_zpsbtrbooce.jpg.html)

So where to get this kind of wire today? Other on the board suggest just buying a cheap RCA cable and snipping off the plugs. The cable will be constructed the same. It's tricky stuff to strip, so be careful when prepping your wire.

Paul
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on February 02, 2018, 02:06:11 PM
Thanks.
It is thinner than I thought.
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on September 08, 2018, 04:29:11 PM
Hello!
Folowing the instructions of Slowpoke101 and Ponce I draw a modified Sabrotone layout. The layout is NOT verified, but the mod should work fine.
We have to check if it's drawn correctly. 8)

(https://s22.postimg.cc/ux4bf7xdp/Chorus_Ensemble_anti-tick_redraw.png) (https://postimg.cc/image/ux4bf7xdp/)

The instructions I received some time ago:

Cut the vero trace at q30 (under IC2). This cuts the trace between IC2 pin 3 and 6.
Cut the vero trace at q32. This cut isolates IC2 pin 6.
The following steps are done on the solder side of your board. The resistor, capacitor and wire link are going to be mounted on the solder side. Keep the component leads as short as possible and make sure that the leads and the components do not short to anything.
Solder the 68K resistor between IC2 pins 3 and 6. This goes across the first cut you made at q30.
Solder the capacitor between IC2 pin 7 (p31) and pin 6 (q31).
Solder the insulated wire link to IC2 pin 3 (q28) and to R31 (q33). This link restores the 4.5V line going to the depth pot.


This is the CE-3 schematic, where there are the two extra components for the anti-tick mod (10nF and 100k):

(https://s22.postimg.cc/kaai9trt9/bossce-3.jpg) (https://postimg.cc/image/kaai9trt9/)
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on September 13, 2018, 04:14:33 AM
Sorry! :o You can read "64 cuts".

From 61 cuts I added, indeed, 3 more cuts, but there's also the thin cut. (See the notes).
Title: Re: Help needed with Boss CE-2 clone project
Post by: Elijah-Baley on October 01, 2018, 05:47:50 AM
I built the original version of the Sabrotone Layout. The circuito works, no hum, no ticking. Really Sweet Chorus! ;D

As for the Zombie Chorus I can't appreciate the vibrato mode, but maybe it's just me.
Cool the Intensity mode. Maybe the speed is not so fast, but I know how I can get it faster.

I can test it just with the guitar, I can't hear any difference between guitar and bass mode. :o Is it normal?