MOTM

Thanks for the information guys. I will be getting an FC-7.

I really appreciate your help!

John Broaddus



--- In motm@y..., WeAreAs1@a... wrote:
> 
> In a message dated 2/7/02 9:49:12 PM, motm@y... writes:
> 
> <<  "corelli44" <john@p...> wrote:
> 
> 
> Hello List,
> 
> 
> I have an old Volume/Modulation pedal that I got with my original 
DX7 
> 
> back in 1985. I'm trying to measure the resistance to see how to 
use 
> 
> it with the pedal interface but I'm not getting very clear numbers.
> 
> 
> I get readings between 25 and 40 most of the time with the pedal up 
> 
> or down. It does go up to as high as 150 sometimes but very briefly 
> 
> (could this be my DVM? It's quite cheap). 
> 
> 
> Also, I only get readings with leads on the very tip and behind the 
> 
> first ring on the plug. I get nothing with one of the leads between 
> 
> the two rings (and the other on either side of either ring). Is 
this 
> 
> the way the newer Yamaha pedals are wired?
> 
> 
> I'm just wondering if older pedals might have been made a bit 
> 
> differently than the newer Yamaha pedals or if they should be 
> 
> somewhat similar (if anyone has any experience with older pedals). 
> 
>  >>
> 
> The foot pedal you have is a model FC4.  The pedal they are 
currently making 
> is the FC-7.  The old FC-4 is an opto-electric pedal.  It contains 
a small 
> incandescent light bulb and a photoresistor.  Two of the TRS plug 
conductors 
> are connected to the photoresistor; the other conductor supplies DC 
voltage 
> to the light bulb.  Movement of the pedal opens and closes a small 
shutter 
> between the bulb and the sensor, allowing in or shutting out the 
light from 
> the bulb.  With no power applied to the lightbulb, moving the pedal 
(opening 
> and closing the window) won't really change the measured value of 
the 
> photoresistor (it's dark in there!).  This is in contrast with the 
newer 
> "passive" FC-7 pedals, which are potentiometer-based, so their 
resistance can 
> be varied with no power connected.
> 
> For more reasons than one, it's probably a better idea for you to 
try to 
> obtain one of the newer pedals for use with your analog equipment.
> 
> Michael Bacich