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The Logictech 2100T supports 3 servo speeds (in the words of the manual).

1. Dedicated Digital Servo(LTS-6100G)
2. Matched Mini Servo
3. Mini Servo for general

For most of us the selection will be either (3) for an analogue servo, or (2) for a digital servo.

I have hooked up an oscilloscope to measure the pulse width and period and have found the following with ATV/EPA set to 140% as per the Logictech setup instructions, limits cleared, and with HH off:

1.
min: 720us
mid: 980us
max: 1240us
frame rate: 3.6ms

2.
min: 1080us
mid: 1450us
max: 2080us
frame rate: 3.6ms

3.
min: 1080us
mid: 1450us
max: 2080us
frame rate: 15ms

Option (1) clearly uses non-standard pulse widths so I'd avoid selecting that for fear of upsetting any connected servo.

Options (2) and (3) differ only in the frame rate.

Oddly the timings for (1) are symetrical 260ms either side of the mid-point, yet (2) and (3) are both 370us/630us min-to-mid/mid-to-max. I thought that may be an artifact of the limit setting, but the rx emits exactly the same timing.

Concerned that the framerate on option (2) might be too high (in light of comments I've read about S3154's failing using DS mode on 401's) and the cause of the failure of my S3154 servo I contacted Ripmax (the UK Futaba importer) who informed me that Futaba specify a minimum frame period of 3.33ms for their digital servos, so the Logictech timing looks good.

Incidently, Ripmax informed me that, to date, they've only had 5 S3154's returned under warranty all for failed motors. Not sure how many they've shipped, but it suggests that the number of failures is not large. Guess I was just lucky.

Steve

Last edited by Steve Evans on Thu Apr 17, 2008 8:54 am; edited 1 time in total