Help! DS-1 mod unsuccessful...

[orni]

Maybe I could have kept my hand in my pocket, but I decided to ask for your help. If it isn't the right place to call for help please forgive me. But if it is you will make an happy man.

I replaced the diodes with LED's and all went fine.
Then I replaced C3 and it was fine too.
I finally replaced C10 and C12 and here the problem began. I have a very nice sound which I'm happy with, but unfortunately the volume and tone pots have now no effect at all. My DS-1 works like it is at full volume.

I don't know how to troubleshoot this. I verified the soldering, made sure I didn't join two tracks on the board that shouldn't be, but I am not experienced enough with modding (this is my first one).

I can live with that as I'm happy with the sound anyway but if the pots were working...

The caps are 400V instead of 50V. Could this be the cause? I wasn't very clever with my ordering.

Could someone give me some general directions on how I could troubleshoot this problem?

[Fret Wire]

What value caps did you replace C10 & C12 with?

[orni]

Both are 470pF

[Peter Snowberg]

This is a perfect place to ask for help.

The voltage rating of your new caps is not a problem.

I don't have a schematic for the DS-1.... anybody got a link?

I'm sure we can figure it out.

It sounds like a short to me. Could there be a solder spatter that landed on another part of the board? Depending on how those controls work, there is the possibility that the robbon cable between the main board and the pot sub-board has a broken connection.... just something to look for.

I can suggest more with a schematic, but right now examine the whole board surface to see if there is a little spatter of solder some place. Use good light and a magnifying glass if you have one around. I've seen solder bridges that are the diameter of a very fine human hair.

[orni]

Thanks!

Here is the topic I found with a picture of the circuit.

http://www.diystompboxes.com/sboxforum/viewtopic.php?t=27409&highlight=ds1

If you follow the line drawn by the grey wire on the left, you will find C10 & C12. The grey caps. They are aligned just in front of with this grey wire.

I used this diagram for chedcking.
I will carefully check again.

[Peter Snowberg]

Those look like they may be much larger than 470pF. What were the numbers on the sides of the original caps?

[orni]

I cannot read, it's written so small and my eyes are bad. I will buy a magnifying glass and also a voltmeter to check this board. I may have broken a line in the copper because I had to enlarge the holes a bit to put the caps in. But I would have no sound in this case, right?

[airhole]

Hey,

I dun contribute much to the forums, but I learn a lot

this I can contribute...
link to schematic Boss DS-1

courtesy of godiksennet.com

http://www.godiksennet.com/images/sch/DS1PG2.jpg

[chrisaxeman]

Hey,

I dun contribute much to the forums, but I learn a lot

this I can contribute...
link to schematic Boss DS-1

courtesy of godiksennet.com

http://www.godiksennet.com/images/sch/DS1PG2.jpg

Cheers Airhole!

Chris.....

[KORGULL]

According to the schematic I have on file, C10 is .01 micro-farad and C12 is .1 micro-farad.

[KORGULL]

I had a problem with one of those ribbon cable connection points coming loose and needing to be re-soldered. Also had something shorting out when I re-assembled the pedal and screwed the back plate down. I had to re-seat the board a couple times.

[phillip]

Yes, if you have a newer version of the DS-1, with either the BA728N chip or the M5223AL chip, C10 is 0.01uF and C12 is 0.1uF as Korgull said.  They're also those values in the older version that had the TA7316 (as in the link posted above) .  

Both of those capacitors are in the tone control section, so replacing them with smaller values will alter how the tone control responds.  It should work correctly once again if you replace the two 470pF with the original values.  You can also try sockets for the tone control capacitors to see if you can alter the "feel" of the tone control more to your liking.

Phillip

[orni]

Thanks for the info, Philip.

This evening, I went home with a magnifier glass and a multimeter.
Checked the board with the magnifier. Nothing wrong.
Could read the old caps values: it reads 473K and 103K. I suppose it's for .047 and .01 It is an old DS-1 I bought 20 years ago... Vintage.    
With the multimeter, I carefully verified all connections and found two mistakes: One track was broken because I had to enlarge the holes for the caps and the second mistake was two tracks joined by error (I think I did that one yesterday)
So now, I am a really happy man. My DS-1 has full working controls. Tone and volume are working!!

The conclusion of this is that if the legs of the caps are too large, better use sandpaper to make it smaller than enlarge the hole.

Thanks a lot four your help! I was nearly giving up and happily you were here!  :lol:  :lol:  :lol:

Hmmm... Modding virus bites me...  I think I'd like to buy another of those boxes and try another mod. Maybe I can learn enough to mod it more exactly as I'd like it to sound?
I don't know. I think I'd like first enjoy playing it. It was for so many years in the basement waiting my experiments...
Thanks again, guys. :lol:

[scottosan]

Stock on C10 is 0.01uf or 10,000pf, Stock on C is 0.047uf or 47,000 pf(i think)

[orni]

Yes. Funny, the mod I did changed one cap with the same value.