TS and Wah

[petesguitar1]

PART 1

Thankyou to all the helpers oput there. Has been great. I've now built 4 Blue Clippers and am fairly comfortable with building them! (Yay for me). I have progressed to a TS from www.tonepad.com. Using one of ZFranciscos PCBs Now I think I have done everything correctly, and have actually left the project for 2 days to come back with a clear head  . I did not want a DC Jack and have used a 3PDT switch with an indicator LED. It works fine. I have used the 3PDT wiring as described in the FAQ for bypass ground wiring with an LED.

Battery is at 8.18 V

So the switching mech from PCB is 9V in --> R22 --> LED --> Switch
                                                           -->Battery Snap (+)

I just joined the 2 wires before the resistor. Anywho, the only change was a 25k Pot instead of 20k.

There were no markings so I have labelled as follows - Looking at the parts layout LEFT to RIGHT - Resistors, then caps etc. I have also added values to help ID.

Results

   Rating      
R1   51   3.88   3.89
R2   1   3.88   3.88
R3   1   3.88   3.82
R4   10   3.85   3.81
R5   1   3.47   3.16
R6 (RB)      0   0
R7   220   0   0
R8   2M2   0   0
R9   1   1.97   2.13
R10   4K7   3.78   3.76
R11   10   3.78   3.74
R12   10   2.28   0
R13   510   3.77   2.12
R14   10   3.76   7.55
R15   510   3.76   2.22
R16   10   2.44   0
R17 (Ra)      2.23   2.44
R18   10   3.75   0

C1   0.22   3.72   0
C2   0.1   3.75   2.2
C3   51pF   3.77   3.76
C4   0.22   3.71   0
C5   1 (NP)   3.75   3.1
C6   0.047   3.71   3.76
C7   1 (NP)   3.69   2.25
C8   10   2.2   0
C9   47   3.71   0

D1      3.73   3.72
D2      3.73   3.72
D3      3.77   3.73

IC   Dot top left      
3.69   3.77      
7.44   3.77      
3.74   3.65      
3.74   0      

         


Q1   2.2   2.06   7.37
Q2   7.36   2.16   2.36


PART 2

I have been given a wah which I have true bypassed with a 3PDT switch and indicator LED. Now I'm not sure why, but the wah won't operate unless something is plugged into the AC jack. It's a Dunlop JH-1. Anyone else with this problem?

Thanks heaps

Pete

[petesguitar1]

Bump

[alderbody]

I have been given a wah which I have true bypassed with a 3PDT switch and indicator LED. Now I'm not sure why, but the wah won't operate unless something is plugged into the AC jack. It's a Dunlop JH-1.

The AC jack has three connection terminals, right?

Two of them are for +9V and one is for ground (-9V)

The two +9V terminals are not connected together because one is supposed to supply voltage when the AC jack is plugged and the other when the jack is bypassed (battery use).

I suspect your problem must be somewhere in there...   

[petesguitar1]

Thanks man, will look some more!

[petesguitar1]

Well, I've had my head in this thing for a few days, and I would really like to get it working, so I'm now offering $5 USD for the person that can solve my problem. That's $5 USD for the TS and $5 USD for the wah - Or I can buy something from Aaron and get it sent to you. 

[Toney]

 

  Ok, on the TS, you've got near full bat voltage at pin 2 and half supply where you should be reading zero (ground pin 4)

Combined with what you describe with the true bypass mod to the wah, I think the most likely place to look is a wiring error with the 3pdt or next up a solder bridge. They can be mighty sneaky and we've all done it. I use a lupe to carefully check.

The wah should be dead simple, you did the mod, right? Well, if all was working correctly previously, you simply have made an error wiring it. Ot's easy to look at the same mistake 25 times before the "aha" moment arrives. Once you've sorted the wah, I'd then to to see if you've doubled up the mistake on the TS.
One thing though, that IC may/may not be fried now, do you have another for testing?

[petesguitar1]

The problem was apparent before the T/B in the wah.

I'm a bit of a spaz - what type of redings should I be getting from the TS? I've searched and can't find them.

Thanks for your help

[Toney]

Here's a voltage guide from GGG.. http://www.generalguitargadgets.com/instructions/tscmr_inst.htm

The Wah is dead simple, if you're certain about the wiring of the 3pdt, you simply need to know how the dc jack works, establish the switch is functioning- use the continuity test of your DMM for this, and wire it correctly with the battery snap.

[petesguitar1]

The following is all in relation to my TS

Now, just to make sure my switch is right

  http://www.diystompboxes.com/pedals/images/3PDTbwiring.jpg

This how I've wired it but where the 9V+ goes into the switch (top middle) I've taken a branch off the red battery lead to also go to the PCB.

Now I'm getting no voltage whatsoever on the PCB

The bypassed state is fine, good strong sound.

Thanks

Pete

[Toney]

Broken wire or short.
Check 9v and ground.

[Toney]

I prefer the Tonepad-style wiring arrangement , switching ground to the LED in the middle lugs of the3pdt.
Check www.tonepad.com

[petesguitar1]

Lol, that's the way I first arranged it  Have gone back to that wiring and it seems to be okay. Still not working, but all the voltages are appearring now. I checked the pinout, and it looks to be correct. I'm using a JRC4558D.

[Toney]

  Ok, check the circuit ground.
Trace it backwards from pin 4 of the IC. It should be at ground. It's getting half supply. Pin 2 is getting way too much voltage.
Pin 5 however IS at ground.

Something is causing this and I presume your transistors are listed EBC?
If so you have near full bat voltage at the emmiter of Q1.
Hmm, check the orientaion of your diodes carefully too, esp the 2n400X style one.

Assuming all component values are correct, it will almost certainly be wiring, soldering or component orientation.
Check too the resister values around the voltage divider.

[petesguitar1]

Wahoooo, Pete is WAH'D up now! I know it's probably a band-aid solution, but I bridged the 2 9V inputs and the wah works a treat. I decided to replace the 3PDT as well, works a treat. As soon as I get a .068uF Cap this sucker is getting the bass treatment!

I've also ommitted the 3PDT and LED from the TS - Changed the IC for a new one - JRC4558D - and I'm now getting voltage in all the right spots on the IC, but only about half the values. (eg should be 4.4, I'm getting 2.2). Any ideas?  This is happening for all pins except ground which is 0.

[Toney]

Getting there...

I'd check that the resisitor values around the voltage divider are correct.

[petesguitar1]

Voltage divider? Sorry, I'm very uneducated

[petesguitar1]

Ok, I just changed the 51pf cap for a 47pf and the Voltage has gone up to approx 3.6 where it's supposed to. I still get no sound whatsoever.

[petesguitar1]

Should I have any voltage after the output cap? I seem to have approximately the right voltages everywhere else.

[petesguitar1]

Anyone?