TS808 Help Please!

[dstahl]

This is my first post. So I hope I did everything ok.
  I built a ts808 via a tonepad circuit board. and now I am getting a barely audible effect coming out of it. I tried rechecking over and over for cold solder joints and resoldered anything that looked suspect. here's the details.
1.Name of the project: TS808 via tonepade
2.tonepad's schematichttp://www.tonepad.com/getFile.asp?id=81
pics of their project build http://www.tonepad.com/photoessay.asp?photoEssayID=24&sequenceNo=10
pics of my board
http://216.220.98.25/david/ts808/solder1.jpg
http://216.220.98.25/david/ts808/board2.jpg
http://216.220.98.25/david/ts808/solder2.jpg

3. and  4. followed build exactly as I could. no modifications or substitutions of what I can tell. checked that any elec caps were correctly polarity (longer leads in square holes on board) Transistors are going in the shape they are supposed to be according to the board.

used a 9 volt that measured 8.45
tried to do all these readings as best I can. it's my first time so please be gentle.

Q1 Facing writing on tran
left = 1.68
center =1.63
right =5.50

Q2
left =1.69
center=1.63
right =5.50

IC1 (or U1)
P1  2.79
P2  3.05
P3  2.75
p4  0
p5  2.75
p6  0
p7  2.91
p8  5.63

D1
A (anode, the non-band end) = 2.73
K (cathode, the banded end) = 3.00

D2
A =2.43
K =2.73

d3
a=2.70
k=2.43


that's it.
any help or suggestions would be appreciated.
thanks
-D

[Cardboard Tube Samurai]

Any reason you used such a large cap across the top of the IC? I'd be looking at swapping that for the one you have over in C1 position... I think you may have mixed the 2 up

[royzic]

hi man,

looking at your pics, some of the solder spots looks suspicious.


-check those  for unwanted connections(could be small),or cold solders.
-check the polarity of the 0.22 caps if they are tantalum
-see if the pots are connected properly

i think pin 6 shouldn't indicate 0 volts

[oldrocker]

Yes since tants are polarized make sure the plus side of the .22 caps are facing in the right orientation.  I used poly film non polarized caps for the .22 in the one I built.  Also I would try and find a ceramic 47p or 51p cap instead of a 500v. I read in another thread that could cause problems.  Is that big blue cap a .047uF or marked 473?  I'm not sure why its that large.

[dstahl]

ok. So I replaced the tant. 0.22 polarized caps with np film caps and also replaced the gargantuan 0.047 blue cap with a standard radio shack green np film cap. and now it seems like I am getting the effect out of it. I won't be able tell till I take it home tonight and play guitar through it with an amp. So, so far so good.
I am curious would not using the polarized tant. caps cause any kind change in the quality of the effect?
  Also. and this might be me jumping the gun, is a recognizable bass drop out usual when engaging the effect?
Thanks so much everyone for all your help so far. I am so grateful for this board and the helpful people on it.
-D

[Hepcat]

 Here are some mods  to try if you want to tweak the sound a little . Its for the GGG layout but probably still applicable http://www.generalguitargadgets.com/pdf/ggg_its8_mods.pdfble.  Have fun  =J=

[m-theory]

is a recognizable bass drop out usual when engaging the effect?

From what I've read, this is pretty typical with a stock TS.  There are some mods that can help, at the GGG site, and also the BYOC site.  Plenty of excellent information on mods right here in the archives as well.  Aside from those mods, I found that red LED's also make a significant impact on low end. I can definitely tell why they call using LED's a "Marshall" mod. 

[tonefreak]

Any reason you used such a large cap across the top of the IC? I'd be looking at swapping that for the one you have over in C1 position... I think you may have mixed the 2 up

That would be my guess as well.

Check:
You have a 47uf where the 51pf (cereamic) should be?
Now, where you currenly have a the 51pf... there should be a 0.1 cap there.
Is that blue cap really a .047uf? 

[oldrocker]

Quote "I am curious would not using the polarized tant. caps cause any kind change in the quality of the effect?" 

It might but it shouldn't be anything drastic if at all.  If you look at the picture on the tonepad site that you posted at the top you'll notice that that's what they used there.  Again as mentioned earlier that large orange 47 500v cap might not be a picofarad but a microfarad cap.  That should be looked into next since that would have a direct effect on the sound if it's too big.
Make sure the 47pf cap isn't swapped with the 47uF cap as mentioned by others.  This would most likely be an easy mistake.

[dstahl]

I couldn't find a 51pf ceramic from small bear, pedal parts, or radio shack. But I read that a 47pf would be acceptable. so I ordered one from small bear (a silver mica).
1 Capacitor Silver Mica 500V 10 pf. - 150 pf.  (47 pf.) @ $0.55 = $0.55
http://www.smallbearelec.com/Detail.bok?no=181 
I am thinking about changing some of the components (including tracking down a ceramic 51pf) , but first want to compare the sound to my ts9 reissue. Still haven't confirmed that it sounds like it should with a guitar. I have been testing at work using pc speakers and an ipod.
  the GGG mods and keely mods look interesting. especially the ones that will give more bass and low end.

[mars_bringer_of_war]

I'd leave the 47pf mica in. A ceramic will have a different tolerance, and the capacitance might not actually be 51pf, though it is labeled as such. Also, the mica will have a slightly smoother sound.

[oldrocker]

Looks like you should be good to go then.  Check it out when you get home and see where you're at with it.  I made this on perf a while back and I think the circuit sounds great as is.  But it's a matter of opinion.
Though it is true that mica caps can sound smoother then ceramic in a TS that may not be what you want.  Again it's a matter of opinion but I like ceramic in certain situations.

[dstahl]

Well. I checked it out at home and.....IT SOUNDS FREAKIN AWESOME!!!
So much so that I had to pull my ts9 off my pedal board to make room for this bad boy.
Thanks so much to everyone on that offered their help.