DS-1 RF problems and OCD popping

[Stratomaster]

Howdy,
     I recently picked up an OCD pedal (no, this isn't another OCD thread) and it doesn't like playing nice with my DS-1.  I use the DS-1 as my primary distortion (it's been modded and sounds better than anything I've tried--I LOVE this pedal!) and layer the OCD on top for leads.  This job used to belong to my TS-9, but the OCD is much better at it.  Anyway, the OCD only pops when engaged if it is before the DS-1 in the signal chain.  Also, it makes the RF interference with the DS-1 more noticeable when the OCD is bypassed.  What's really strange is that when both pedals are on, the RF interference goes away.  I was thinking this may be an impedance mis-match issue.  If that's the case, how do I fix it?  I was also considering true-bypassing the DS-1, but it sounds like a hassle and would only solve the RF and popping problems while the pedal is off.  I'm really stumped!  Thanks in advance.

[BJF]

Hi,

The popping is likely caused by the input cap of your DS-1 floating-  connect a 1M resistor to ground from inputjack pole on the DS-1.

The OCD is true bypass and eachtime you toggle the OCD switch theinput cap on the DS-1 discharges.

RF problem: you might want to try limiting the useful bandwidth to audio by restricting the gain at HF with the firts gain transistor of DS-1 ( that's if it is an old one). There are various points that can be troublesome and you may have to experiment.

Got to run have fun
BJ

[Stratomaster]

Howdy,
     I tried the 1M resistor with no such luck.  You do mean from one solder lug (hot input) to one of the 2 other ground lugs on the same jack, correct?  What I noticed is that if I put a TS-9 in between the two, the pop decreases dramatically.  This gives me the idea to modify the DS-1 to have an always on TS-9 style input buffer.  I would just put a TS-9 in between the two, but my board real estate is precious.  Maybe I'm just not putting the pull-down resistor in correctly.  Does any of this make sense?
-Omar

[Stratomaster]

Bump-ness.

I guess the main question is, how do I install that 1M resistor.  Was I right to put it from the hot lug to the solder lug on the input jack?  Thanks!

[Barcode80]

sort of, although you probably should have soldered it on the circuit itself. solder it to a jack and about 50 plug in/pull-out cycles will likely break the connection. the reason the pop goes away when you run the ds-1 first in the chain is because the buffer stage of the ds-1 prevents it from happening. it seems the problem is with the OCD. try placing a 1M from signal input to ground on the OCD circuit. should clear it up.

[Stratomaster]

The problem with that is that the pop only happens with the DS-1.  If I put any other pedal after the OCD, it doesn't happen.  There's something else going on with this set-up, and it's driving me nuts.  Every other pedal I put after the OCD does not cause this popping.  It likely is the DS-1, but I don't know how to fix it.  Is there anything else that could be causing this interaction problem?  Back when I used my true-bypass wah and DS-1 there was no popping.  So it isn't a true-bypass issue.  Any and all help would be greatly appreciated.

[Stratomaster]

Bump 2.

[Stratomaster]

SOLVED!!!

I used the IC buffer from ggg and it worked beautifully.  Increased the RF though, but then I popped a 100pF cap across the input and ground connections on my perfboard.  Everything's back to normal, but there's a little bit of a change to the sound of my wah.  If this doesn't work out, I'll sub in the TS-9 buffer.

Just in case this happens to anyone, I want the solution documented here.

-OMJ