Sanwa Gemini - Function Question

[randhart]

Hi there!

I just got a second hand Gemini and unfortunately no manual. I was wondering what all the little dials and stuff on it means things like:

1) ultimate Proportional Efficiency Dial (ST D/R) Min to Max

2) SUB.T. Dial - L through N to R

3) E.P.A. For both Stearing and Throttle - Min to Max

4) A.R.C. For stearing Lin to Max Dial and a Mild to Quick Switch

For Throttle Lin to Mild Dial

Thanks for any help you can Give!

Regards

R

[sosidge]

I used to have one of these!

1) ST D/R is the steering dual rate. This is used to limit the steering lock if necessary for the track conditions. Start with this at maximum.

2) Sub T is the sub-trimmer. This is a "master" trim for the steering servo. use it to get the servo centred with the linkages in the car set up evenly. Then, use the normal trim for small adjustments while running.

3) EPA is end point adjustment. Start with it all at maximum. With the throttle, an electric car can be left at maximum as the ESC will set itself up. On a nitro car, it may be useful to limit the throw of the throttle servo to get the linkage just right. With the steering, it should be set to the maximum travel possible without the servo straining or the cars driveshafts grabbing.

4) ARC is the steering curve. Linear is a linear response, e.g. 50% stick will give 50% lock. When set to "quick", with the dial turned, the steering will feel more responsive around the centre, smaller movements of the stick will give larger movements of the servo. As an example, 50% stick may actually be 80% lock. Mild makes the steering less responsive around the centre, as an example 50% stick may be only 20% lock at an extreme setting.

5) Throttle ARC will make the throttle feel less responsive near neutral if set towards mild.

Here is my recommendation for setting the radio up.

Step 1: Make sure the steering linkages are set up evenly, and then use the SUB T to get the servo to a geometrically true master neutral.

Step 2: Set the steering EPA for full lock with no straining or binding on both left and right.

You are now ready to run the car.

Use the normal trim to get the car running straight. If you need to use lots of trim you have either got the sub trim in a less than perfect place, or there is a mechanical problem with the car that is pulling it to the side (transmission problem or chassis tweak).

If the car has "too much" steering for the track, you may want to turn down the ST D/R knob. A few tips - don't take away too much lock because you won't be able to get out of a sticky situation (as a minimum you should be able to turn 360deg in the tracks width), and also don't use transmitter settings to cure a bad handling car - it is still a bad handling car, just in disguise!

If the car feels "twitchy" when you make small steering adjustments, you may want to make the steering ARC "mild" and turn the knob a little. If it feels numb near the centre you may want to use the "quick" setting. Note that changing the EPA will also make the car feel like it has more/less understeer as well, this is a side effect, not the main use of it. Avoid large changes - again, you are just disguising a fundamental handling problem!

If the throttle feels too responsive at low speed, you may want to make the throttle ARC a little milder.

That is about it, it is a good radio, and the settings it has are pretty much all you need! The only thing it lacks compared to the modern radios is the precision of digital trims and a memory.

[randhart]

Thankyou for your very informative answer!