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DIY Stompboxes => Building your own stompbox => Topic started by: tvjoda on May 26, 2017, 11:28:19 PM

Title: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 26, 2017, 11:28:19 PM
Hello, I make the ds1 and it sounds good but with very little distortion, the gain potentiometer from 0 to 8 does not make distortion and from 8 to 10 it does, but it seems an overdrive more than a distortion, is this the real behavior?

need help please, i can send values from components, pictures, audios, you name it,

thanks
Title: Re: Tonepad Boss Ds1 Problem
Post by: Agung Kurniawan on May 27, 2017, 01:03:40 AM
what value do you use for gain pot? 100k?
did this is your first time building a guitar effect?
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 27, 2017, 11:10:58 AM
Yes I am using a 100k B pot and ,no is not my first pedal, I make the rebote delay 2.5 and the tubescreamer
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on May 27, 2017, 12:07:05 PM
Hello and welcome,

Did you build the transistor version or the op amp version?
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 27, 2017, 07:17:08 PM
I choose The tl072 versión Here is a picture off The board

(https://s9.postimg.org/bzmo9nrd7/IMG_20170515_211444418.jpg) (https://postimg.org/image/bzmo9nrd7/)



(https://s21.postimg.org/uhddb383n/IMG_20170511_202411834.jpg) (https://postimg.org/image/uhddb383n/)
 Thanks guys
Title: Re: Tonepad Boss Ds1 Problem
Post by: Cozybuilder on May 27, 2017, 08:31:27 PM
It looks like there might be a couple of solder bridges. Use your magnifying glass and verify, and correct if there are.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 27, 2017, 09:09:53 PM
The picture does not have good Quality, I double check check that and whit the tester, I think the tracks are fine, but i am going to check again, thanks
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 27, 2017, 11:32:27 PM
I AM thinking to start all Over, does anyone try this PCB?
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on May 28, 2017, 01:00:51 AM
The problem may not be so big to try starting over. What I would check is that the resistors are the correct value, for example, 4.7K not 470ohms, or something like that. If you are only having trouble with the distortion boost in a kit like this, but the kit is working OK otherwise, my first guess is a resistor got switched, or maybe a transistor is in backwards.

Is C3 supposed to be empty or have a jumper wire?
Title: Re: Tonepad Boss Ds1 Problem
Post by: ElectricDruid on May 28, 2017, 01:15:53 PM
I AM thinking to start all Over, does anyone try this PCB?

Don't give up that easily! There's enough people here who can help you find what's wrong with it. It's usually something simple, although sometimes it can be hard to find.

http://www.tonepad.com/getFile.asp?id=78 (http://www.tonepad.com/getFile.asp?id=78)

But "not enough gain" is a fairly simple problem. Given the pdf has two sets of components on the same page and no simple schematic (instead, you have to "paste in" a piece to 8 awkwardly arranged connections) I can see that errors would be highly likely.

Looking at your image, it looks like you've got a link in place for R1, where the parts list says it should be empty.  You've also got a link for C3, also marked as empty. Is this right?

I'd go through the parts in detail and check each one - a bit tedious, but you'll find the mistake, and then you'll be up and running!

HTH,
Tom

 
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 28, 2017, 04:13:46 PM
Thank you Tom Ford giving me hope ,is true I thinking the board looks fine, about the r1 and c3 I removed the links but still doing the same overdrive


(https://s21.postimg.org/6dh8zbi03/IMG_20170528_162045412.jpg) (https://postimg.org/image/6dh8zbi03/)


Thank you again all people, i can make it with your help

I AM not sure about the transitors , could be a bad
transistor?
Title: Re: Tonepad Boss Ds1 Problem
Post by: ElectricDruid on May 28, 2017, 05:06:15 PM
It *could* be a bad transistor, or it could be in back-to-front, as suggested above.

Can you take a sharper/larger photo of the board so we can take a proper look?

Tom
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 28, 2017, 07:34:56 PM
Yes sure, please let me know if this photos are good
About the transistors orientation I followed the instrucctions from the draw in the schematic

If they are backwards is posible that it sound but with less distortion?

(https://s1.postimg.org/vs9pr5jy3/DSC_0221.jpg) (https://postimg.org/image/vs9pr5jy3/)

(https://s11.postimg.org/9j3fx4gnj/DSC_0225.jpg) (https://postimg.org/image/9j3fx4gnj/)

(https://s2.postimg.org/rthv7wto5/DSC_0229.jpg) (https://postimg.org/image/rthv7wto5/)

(https://s17.postimg.org/3qf94szdn/DSC_0230.jpg) (https://postimg.org/image/3qf94szdn/)
Title: Re: Tonepad Boss Ds1 Problem
Post by: graemestrat on May 29, 2017, 06:00:45 AM
Hello,

On the rear view of your pcb on the trace that runs around the edge of the board, in the corner, there is a wire poking through this trace that is not soldered.
You might want to check what that is?
Title: Re: Tonepad Boss Ds1 Problem
Post by: ElectricDruid on May 29, 2017, 09:07:15 AM
I had a look around and I couldn't see any component values that didn't look right. There's a couple I can't see on the photo, but it all looks pretty good from that point of view.

About the only thing that made a little flag go up was that you've got a green and a yellow wire bring the input onto the board. And the *yellow* wire is the ground. I'd have expected the green, and then I'd have wired it up like that at the other end and it wouldn't have worked.

Have you checked the off-board stuff? Wiring ok? right pots in the right places? (using the tone control for gain by mistake would reduce gain).

Did you use the specified 2N5088 transistors? If not, they might not have the same CBE pinout.

Have you got an audio probe? I think you might need to start tracing the signal through the circuit to find out how far it gets.

HTH,
Tom
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 29, 2017, 10:59:30 AM
Hello , yes is true, i use the yellow for the ground and the green for the input, they are connected right and the colors are wrong but it just the color
about the transistor yes i used the 2n5088.
I tested the signal and I am getting 9 volts where it should be, not sure how to keep going, could be a wrong value on capacitor or a resistence, but I checked like 20 times and I dont see the error
I am thinking that maybe the circuit is sounding as it have to be, is it good if I upload a video showing the effect how it sound?
does anyone has a video on how should sounded the tonepad ds1 with the tl072?
Title: Re: Tonepad Boss Ds1 Problem
Post by: MrStab on May 29, 2017, 11:55:38 PM
hi tvjoda,

if the problem isn't earlier in the signal path, like the transistors or something, then maybe the problem is with the gain stage. does the Distortion pot measure the expected resistance as you turn it? maybe the first 80% of the rotation is damaged, or maybe there's a problem with the 470n capacitor (C8).

other areas to check are maybe R11, R13 and C7 (http://cdn.tonegeek.com/wp-content/uploads/Boss-DS-1-schematic.png (http://cdn.tonegeek.com/wp-content/uploads/Boss-DS-1-schematic.png)). Maybe R40, too.

you could also try reducing R13 to 2k2 to see if you just prefer more distortion than the DS-1 has available. if you do this, you'll have to raise C8 to 1u for the same 72Hz response.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 30, 2017, 11:38:35 AM
Hello Mr stab, thanks for The reply I try with a new port and i used The tester to measure and The pots are looking good, i AM not sure what value change
I AM using this schemactic

(https://s10.postimg.org/9pgy7m7bp/Screenshot_20170530-123134.png) (https://postimg.org/image/9pgy7m7bp/)
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on May 30, 2017, 10:50:44 PM
What could happen if I turned the transistors?
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on May 30, 2017, 11:13:54 PM
Best just to make sure they are in correctly.
Title: Re: Tonepad Boss Ds1 Problem
Post by: stringsthings on May 31, 2017, 12:42:39 AM
I'd measure the voltages on the IC and the transistor.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 02, 2017, 02:52:26 PM
sure no problem

Battery 8.73

IC
4.35     8.73
4.35     4.35
3.78     4.35
0          4.35

Q1
E
3.22     2.73      8.73

Q2
E
0.02        0.66       0.96

Q3
E
2.83      1.95        8.73
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 02, 2017, 05:52:27 PM
The readings on 2 look a bit odd. I would check the resistors around Q2, for the right values.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 02, 2017, 09:12:39 PM
(https://s18.postimg.org/xmvba78f9/DSC_0229-_Measures.jpg) (https://postimg.org/image/xmvba78f9/)

code values

C1 : 474
C2 : 223
C3 : 683
C4 : 471
C5 : 473
R1 : blue , gray, red
R2 : red , red, red
R3 : blue , gray, red
R4 : brown, black, orange
R5 : brown, black, yellow
R6 : brown, black, yellow
R7 : brown, black, green
R8 : red, red, black
R9 : yellow, purple, yellow
R10 : brown, black, orange


Is this information useful?
Title: Re: Tonepad Boss Ds1 Problem
Post by: ElectricDruid on June 03, 2017, 09:50:47 AM
The readings on 2 look a bit odd. I would check the resistors around Q2, for the right values.

The readings around Q2 do look odd. Checking the values form your image, that looks ok, so I'd check the soldering and for shorts. It looks to me like something is shorting and pulling the voltage down.

HTH,
Tom
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 03, 2017, 11:22:23 AM
If I measure the voltage at resistance 4 at the input it gives me 8.73 and at the output I have 0.96
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 03, 2017, 02:02:49 PM
Yes. What I would do would be to consider each resistor that is attached to Q2, measure the voltage at each end, and see if it tells us that there is an open or short. Something is making that transistor not transist.

Come to think of it, Q1's and Q3's emitter are higher than their bases. Is this right?
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 03, 2017, 02:34:08 PM
Ok thanks i am going to do that, but the r4 the voltage at the end is wrong right?
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 03, 2017, 03:12:52 PM
R4, as you have labeled it, connects from +v to the collector of Q2. Both voltages line up with your voltage readings, but the collector voltage should read much higher, perhaps between 5V to 6V. This would indicate that the transistor is not transisting, and the culprit may be a wrong resistor value or a short somewhere. I would look for the short, even if you have scraped between the traces, maybe take another pass. But you should still look at voltages at each end of each resistor attached to Q2. Q1 might be suspect as well, but if there is one voltage out of spec, it might affect all of the other readings as well.
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 03, 2017, 03:23:09 PM
Now for a brief intermission:

Read this thread (http://www.diystompboxes.com/smfforum/index.php?topic=108346.0) and see if you don't see something familiar. Hint: Different manufacturers of transistors may have different pinouts. Before removing anything, check the face of each transistor and note the numbers and manufacturer, then check against their datasheet. You have built the pedal according to instructions as far as I can see, but this is an issue that pops up from time to time. We'll be glad to answer any questions that you may have along the way.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 03, 2017, 06:31:36 PM
At the end off The post that you mention he sayd

The Qs still gave the same readings, so I thought lets just flip em round (i'm finding different pinouts for the same transistor!!)

I don't know if i should do the same
It looks like he was having The same values and problem than me
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 03, 2017, 07:53:47 PM
Similar. Sometimes we move something that fixes it but we thought we were doing something else. Having a 22R instead of a 2M2 will definitely make trouble. Nonetheless, if all of your resistors and traces seem OK, I would see about getting the datasheet for your transistors just to verify the pinout. 2N5088s are pretty consistent. Do you want to take a photo of one of your transistors face and upload it for the committee?
Title: Re: Tonepad Boss Ds1 Problem
Post by: ElectricDruid on June 04, 2017, 07:50:39 AM
Ugh..same transistors, different pinout drives me crazy. I've seen the same thing with voltage regulators too, but only negative ones, so far.

Definitely worth a check. If you bought the transistors online somewhere, they should have a link to the datasheet (if they don't..well, they should!!).

Tom
Title: Re: Tonepad Boss Ds1 Problem
Post by: griff10672 on June 04, 2017, 09:11:34 AM
I'm currently doing a lot of messing around with the DS1 circuit ......... I'm pretty much a noob at building ..... but ... one thing I noticed about the DS-1  .... it does what you describe even as a stock circuit .... I've always noticed that .... totally seems like a a overdrive till you have it on 10 ...  which I always assumed was because it isn't a " hi gain " pedal .

I just got done mocking up a " very " modded DS-1 .... and am sort of having the same trouble with the level ... all the way off it's silent .. turn it up just a little and it's cranked ... and stays just as loud as I turn it up .... wondering if I have the dam pot hooked up backwards or something .

Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 04, 2017, 11:32:35 AM
I can't make a good photo off The transistor, but it says
F 408
2n
5088
[IMG_20170604_122532906.jpg](https://postimg.org/image/hzsh5y45v/)
https://postimg.org/image/hzsh5y45v/
Title: Re: Tonepad Boss Ds1 Low Output Normal?
Post by: robthequiet on June 04, 2017, 12:54:40 PM
So the search engines seem to think that it's a Fairchild 5088 from a few years back, in a TO-92. The pinout looks correct as you have it:

Datasheet: https://www.onsemi.com/pub/Collateral/2N5088-D.PDF

As our colleague griff10672 posted, this does not seem to be a unique problem. So having gone through the troubleshooting so far, I'm pretty confident that you built the thing correctly and perhaps a stray solder bridge or open connection exists, although it looks like your cleanup on the board is not bad.

If you feel like doing some surgery, you could simply move the transistors around without flipping them, so Q1 <-> Q2, for instance, carefully not to overheat them. This might auto-correct any microscopic issues with the boards or components. Also, if the voltage issue moves with the transistor, you know which one is bad.



Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 04, 2017, 01:15:33 PM
Thanks robthequiet i already did that, I changed order q1 to Q2 and the values were The same ,then i use an alternative for q2 the bc549 o something like that , and nothing, values and sound are The same , in the other thread, the guy was having the same values as my, but them when he rotated the q's the values change completly, i think that is my last bullet in this pedal
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 04, 2017, 03:15:45 PM
Well, go for it.

You might be interested in this,

http://www.diystompboxes.com/DIYFiles/up/Build_Your_Own_DS-1_Distortion.pdf

Has a lot of good information.

Let us know what happens.
Title: Re: Tonepad Boss Ds1 Problem - Low gain?
Post by: robthequiet on June 04, 2017, 04:04:32 PM
P.P.S.

So I was looking at the schematic assuming Tonepad knows a lot about circuits and definitely more than I. Nevertheless, comparing their schematic to a couple of others it struck me that a 1M biasing resistor to ground might be a bit heavy.

If you have a resistor between 100K and 470K maybe just clip it across R4 to see if you get better performance. My theory is that Q2 is possibly mis-biased.

I would also try the same with Q1, try swapping a 100K resistor for the 470K. Do one at a time so that we see the effect at every move.

These are experimental probes I would try myself, it might be wise to get a second opinion.
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 04, 2017, 04:12:33 PM
Ok i tryed changing the orientation and it sound with Even less distortion jaja

So yes i can try change some parts

Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 06, 2017, 09:44:51 PM
Hey guys, I changed the R4, C1, C4 and C5 for the values from the other list 7a7136p and is good, the sound is much better , less noise, more distortion but I feel like it could have more distortion at level 100, does anybody knows if i can make the Kelley mod to the tonepad version?
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 06, 2017, 11:16:14 PM
Excellent!  :icon_biggrin:

If you want to mod the pedal, you need to find a schematic or list of parts to change, probably both. The DS-1 is a very popular pedal to mod., so there are quite a few options. There is a build report on Tonepad by a builder called Solderman that translates the Keeley mod into the Tonepad layout, you might want to start there. There is also an article in  Premiere Guitar
 (https://www.premierguitar.com/articles/boss-ds-1-mods-1?page=2) that would be good reading. You have to be able to match the part numbers from the original box to the Tonepad layout, as the Solderman fellow has done.

Do you just want gain or do you want to change the tone?
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 09, 2017, 10:47:53 AM
More gain, I started to change some resistors and capacitor values, but I think it will not have the gain from the original ds1, so I will leave it like that and start a new pedal

thanks for all
Title: Re: Tonepad Boss Ds1 Problem
Post by: robthequiet on June 09, 2017, 01:59:17 PM
Glad to help if I can be of help. Maybe consider a Rat or a Big Muff?
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 09, 2017, 06:41:41 PM
I Was thinking in bsiab2, now i want a súper high
gain
Thanks for your help brother
Greetings from argentina
Title: Re: Tonepad Boss Ds1 Problem
Post by: tvjoda on June 21, 2017, 10:07:14 AM
Finally disarm the tonepad pedal, I seted another scheme and works perfect, very similar to the original and you can add the kelly mod, I recommend the true-by-pass version from this scheme before the tonepad

here is the link
thanks
http://www.diystompboxes.com/DIYFiles/up/Build_Your_Own_DS-1_Distortion.pdf
Title: Re: Tonepad Boss Ds1 Problem
Post by: sertan on January 21, 2021, 06:41:03 AM
Had the same problem, spent hours on it, applied some of the changes you did and solderman recommended in tonepad build notes .

In the end solved it by changing the feedback resistor (R3) of Q2 to a higher value. Making it 470k instead of 100K immediately increased the voltage of the transistor from 0.2 to 4.5V and distortion started working as expected. So if transistor stops doing its work, increase this resistor.

Now I am having another problem with final clipping not working anymore... It used to clip a lot and leds were burning when doing so, now suddenly it has stopped clipping completely, no change occurs.. Not sure it is any of the changes I introduced to fix the Q2 transistor bias problem.
Title: Re: Tonepad Boss Ds1 Problem
Post by: iainpunk on January 21, 2021, 08:56:57 AM
welcome to the forum,

its probably not that changed resistor, since it doesn't really interact with the diodes. do you have pictures of your board, the problem might become visible to experienced eyes.

does it put out sound like its supposed to?
if not, post the voltages on all the IC pins.
(https://www.amiga-stuff.com/hardware/images/DIP-numbering.gif)

cheers, Iain