Ring Frobnicator question

[newperson]

Hi,
I have come back to this project after a couple years of it sitting.  It did work at some point then did not.  Now I am back to it.  I can get the trem part of it working with a weak battery or putting 3leds in there, or 2 + a dio, or a dio after the battery before the input.  I cannot get the ring mod to work.  All it does is make a tone that will adjust with the pot.  It does sounds like it is doing the effect behind the solid tone, but the tone outweights the ring mod effect.  What can fix this problem?  The small pot that mounts into the box does not seem to control anything for me.  And I really do not understand how to hook up the bias thing others have spoke about in the past with this project.  I am still new and need really slow instructions.   
Thank you for any help and all the other information on the board,
-paul.

[newperson]

any help?

[Connoisseur of Distortion]

these problems have been covered extensively. you should probably search for information... seems like a thread about this effect comes up every couple of months.

[jmusser]

When you do a search, look for MartyMart. He is the one that whipped this circuit into shape, which had been plagued with problems for a long time. Be sure you build it to R.G.'s GEO schematic, instead of the original John Hollis schematic, which has errors.

[MartyMart]

When you find my post, you'll see some details.
The LED's all have to be "the same type" 3mm standard RED worked for me.
( not ultra brights etc )
With LED's from a different "batch" I had poor results.
The "Ring modulation" is tricky, but I found a place on the pots
where the "tone/note" was as background as possible, or "tuned" to
the part you are playing, with ringmod happening on top.
Takes some "tweaking" but worth it, if only for the trem, which is
fantastic !

marty.

[newperson]

Hi,
Thanks for the reply. 

I have looed around on the board before I posted the question, and I have tried the method used by the other people.  But I am still having trouble with the ring mod part of the pedal.  Does it have to be biased with the extra pot to work? 

I can get the tremolo to work just fine with the above stated methods, it is just the ring mod that I am having an issue with.  Does the onboard pot control the tone level for the ring mod?  Should it lower the solid tone out of the effect?  Mine does not seem to do anything.  Is is possible that I ruined it somehow when putting it on the board?

-Paul.

[MartyMart]

"Yup, I was pleased to get that one right !
so, to sum up :

2X 3mm red LED
1X 3mm red LED (same batch) + 1X 1N4148
20k trim from 9v to the 3mm LED pair set for 3.2 - 3.4 volts across them
100k trim as per the schem
Done !!

Marty"

This is from my original post, the 20k trimmer gets the "bias voltage" right
which seemed to be 3.2 - 3.4 volts
The other 100k trimmer is used to fine tune the effect.
When not set right, you'll have no "trem" at all or very weak trem.
If you have tremolo working well, then the circuit is working !
You just need to adjust the "off board" pots for an optimum sound
the "tone" wont go away totally  !
I gave the unit 10/10 for trem and 5/10 for ring mod ....

Marty.

[newperson]

Hello again,
I have gotten the tremolo to work just fine, but the overtone on the ring is much louder than the effect.  The 100k pot (onboard) does not seem to change anything for me.  The tremolo effect works just the same when it is turned in any direction.  The tremolo effect is loud, clear, and has a good range of adjustment.  No complaints here.

The off board pot adjusts the pitch of the effect/overtone.  If I add the extra trim pot to bias the voltage will that help out the ring mod effect overtone?  Sorry to seem slow at this.  I am still new at this stuff.

The added bias pot will have three legs.  Where would they attach?  Will they be added on the board or between the wiring?  For example, will one of the pot's legs go the 9volt wiring before it attaches to the board, or will it just attach at the board where the +9volt side goes?  And for the other far leg of the pot, would it go to the board where the LED set goes in the board?  And then where would the middle leg of the pot go? 

I have messed around with it a bit and cannot fully understand how this attaches to the board to bias it.  A picture would be very helpful to me, or some detailed instructions.

Thank you again for your replies and helping a newbie figure out biasing,
-Paul.


2X 3mm red LED
1X 3mm red LED (same batch) + 1X 1N4148
20k trim from 9v to the 3mm LED pair set for 3.2 - 3.4 volts across them
100k trim as per the schem
Done !!

This is from my original post, the 20k trimmer gets the "bias voltage" right
which seemed to be 3.2 - 3.4 volts
The other 100k trimmer is used to fine tune the effect.
When not set right, you'll have no "trem" at all or very weak trem.
If you have tremolo working well, then the circuit is working !
You just need to adjust the "off board" pots for an optimum sound
the "tone" wont go away totally  !

[MartyMart]

OK, you have a 9v point entering the board.
The small trim pot has three "lugs" just like a full sized pot :

l  l  l
3 2  1   making a small triangle

Connect 3&2 together to the 9v rail, either bend 2 to touch 3 and solder
or use three "board holes" and a small soldered jumper to connect 3&2
connect 1 to the top of the pair of LED's, so that you can adjust
with the trimmer, the amout of current the LED's recieve.
Using a DMM, black to ground and red to this "connection" at the
LED's,  adjust trim til you get about 3.2 to 3.4 volts
Done !

Cheers,
Marty.

[newperson]

Thanks again,

I will try this tonight and see if it works.

-p.