Erratic Control - JR XP652 & Comparator Interface erratic

[m0cke]

[Wayne Tarr]

You've got the dreaded noise. The interface is working as well as it can. Try a really high quality shielded audio cable and incorporate a low pass filter. To do this go to my site and download the manual I have written. This has details of a filter design. Also consider the serial interface - much better for noise rejection.

Wayne.
wt@hnpl.net www.hnpl.net/wt

[bsergeev]

Try using a shielded cable. A good source of high quality cables is your local computer junk yard. ;-)
Tails of dead computer mice work great: they have several wires (you'll need only 2) shielded by foil beneath the outer plastic insulation.
Though the source of your problems may not be noise, shileded cable always help.
I'm reluctant to write off all the problems on the noise because I tested several different TXs with the same PC and had different results: JR 622 was rock solid while couple of Futaba TXs showed horrible jitter (when used with JR 652 circuit and 6-pin DIN connector).
I know a guy who had his old JR Max4 working fine with 652-cable and he got into calibration trouble when he switched to a newer JR X-347 (with the same cable/PC).
Most likely, the duddy-connector signals vary slightly from one JR model to another.