GCP and 2 volume pedal problem

[Babymax]

Hello,
I have a GCP last version with a FV500L and a FV500H, noth connected with expression jack out and TRS cable.
First problem is:
CGP with one FV500 -> CC go from 0 to 127
CPG with both FV500 -> CC go from 0 to 125 ???
both FV500 with expression jack out have about 0 to 10K
If I connect FV500L with expression out (10K) and FV500H with patch cable in jack in and jack out (250K) i don't have the problem, why???
Second problem is:
I want to have an expression pedal with value 0-->127 and the other with value 127-->0. How reverse the polarity on GCP (or on cable)? there is no polarity switch on FV500 pedals.

Thank you for your help.
Bruno

[JohnClark]

You may have to slightly rotate the pot in one of the pedals, if you can get to it, in order to see the full 0-127 sweep. It looks as if in the full toe position that one of the pedals is not hitting the 10k pot's endpoint.

Reversing the sweep could be as easy as swapping the two outside wires on the pot, however whatever MIDI device you are controlling may be able to accomplish this via programming a custom sweep profile. It is very uncommon to need to reverse the sweep at the pedal itself when using it in a MIDI system.

[Lars Blomstrand]

Hello,

I have exactly the same problem with two FV-500L pedals. The "funny thing" is that if I connect just one a pedal the sweep goes all the way from 0 to 127 but as soon as I connect the second pedal (no matter which) it results in a full sweep limit for both pedals to only 0-125.
It is impossible to adjust the potentiometers inside the pedals but I unscrewed the pot and tested if I get the right values ​​outside the normal "traveling" but I still could not reach the remaining 126-127 anyway.

I have two questions:
1, Is the 500L version pedal a "too low impedance" for the GCP. Two pedals in parallel seams to load the reference voltage too much so that it goes down a few millivolts, resulting in an error "max" value?
2, Would a "pull up resitor" help this situation or is there some power limit resistor I could change so it comes a little more power to the pedal pot?

Kind regards,
Lars Blomstrand

[JohnClark]

Hello,

I have exactly the same problem with two FV-500L pedals. The "funny thing" is that if I connect just one a pedal the sweep goes all the way from 0 to 127 but as soon as I connect the second pedal (no matter which) it results in a full sweep limit for both pedals to only 0-125.
It is impossible to adjust the potentiometers inside the pedals but I unscrewed the pot and tested if I get the right values ​​outside the normal "traveling" but I still could not reach the remaining 126-127 anyway.

I have two questions:
1, Is the 500L version pedal a "too low impedance" for the GCP. Two pedals in parallel seams to load the reference voltage too much so that it goes down a few millivolts, resulting in an error "max" value?
2, Would a "pull up resitor" help this situation or is there some power limit resistor I could change so it comes a little more power to the pedal pot?

Kind regards,
Lars Blomstrand

In this case yes, the two pedals are pulling the reference voltage down too low. If you want to do the fix yourself, lowering the value of R22 should fix the problem.

Let me know if you run into any problems.

[Lars Blomstrand]

Hi John,

Thank you for the info.
I put a 300ohm resistor in parallel with the R22 ( 220ohm ) and that made it working.

Best regards,
Lars blomstrand