rodp2

Hi All,

First post in this forum! I have a specific problem with a servo tester (i think) but can't figure out which section to put this in so apologies for putting this in the Club House (the servo section was manufacturer specific so this doesn't really help).

I've just been trying to use a standard servo (GWS ervo, S03N STD) with a little test circuit that I bought (see picture). The circuit has some instructions with a title of 'Servo Check - Part Number 1-935'. However, it's not working right. When ever you switch it on, the servo rotates anticlockwise for a split second then stops. This happens when you are in manual or auto mode and whether you have the chip plugged in or not. Changing the position of the potentiometer has no effect either. Each time you turn it on, the servo turns anticlockwise for a split second then nothing else happens.

Do you think this sounds like the servo which is broke or the actual circuit (possibly the little IC)? I've checked the volatge is enough (4 new AA batteries => 6v) and the servo is connected correctly. In case you can't read the IC in the picture, it has the details:

12F675

I/P2CD

0305

hmmm, it's a pic - could it have lost it's programming? What do i do now?!! I don't have any other means to test the servo other than buying another tester but would be grateful for anyone's advise.

What about this one:

http://www.servoshop.co.uk/index.php...0610&area=ACCS

Another issue, I'm not actually sure whether this servo will have enough torque for what I require (but won't know until I can test it out). Can you purchase an alternate which comes in the same case size (~40mm x 20mm) and location of the spindle?

Many thanks in advance for your replies.

Rodp2

TheyDontWantMusic

http://www.hobbycity.com/hobbycity/s...dProduct=11780

there are hundreds of standard sized servos.

what are you using it for?

its possible the pic has lost its program, or was never programmed properly.

thats about all the input I can offer, sorry.

scale only 4 me

My Feedback: (158)

Why you'd spend any extra money to test out or repair a $10 servo is beyond me,,

That is a standard 48oz servo

Specifications:

Speed (at max or min control pulse width):
0.23 sec/60 degrees at 4.8V
0.18 sec/60 degrees at 6.0V

Torque:
47 oz-inches (3.40 kg-cm) at 4.8V
56 oz-inches (4.00 kg-cm) at 6.0V
Size: LxWxH (1.40 x 0.79 x 1.40) inches; (39.5 x 20.0 x 35.6) mm
Weight: 1.45 oz (41.0 grams)


good luck

KW_Counter

Does the servo work with a receiver?
If yes, the tester is shot.
If no, the servo is shot and the tester may still be shot.
Good Luck,
KW_Counter

rodp2

Hi All,

Thanks for the replies. The server is actually going to be used to control the cabin air distribution box in my Car (the normal 'plastic' shaft keeps breaking! it's a Saab 9-3 1999). I've not got any other means to test it (ie. no rc devices) and in terms of end use, I'll continue to use it with the servo tester device once working. I try to contact the manufacturer of the tester as maybe they can send me another chip but in terms of choosing another servo with the same dimensions and higher torque, there seem to be so many to choose from - I've been looking at www.servodatabase.com. I've narrowed them down to size and analogue with torque of around 10Kg/cm, but I basically think I'll need to pop into a good hobby shop close to where I live to ensure I purchase a tester that will work with it and can return / swap, if it's not good.

If anyone lives in the High Wycombe / Buckinghamshire or Hayes / Middlesex in UK and know of a good shop that sells a good range of servos, I'd be grateful for their name and details?

So it looks like I'm going to have to buy some more bits.... I now have to decide whether to buy a new servo or whether to buy the actual car specific stepper motor device(c. £30)but then I'd need to design a control unit for it which I'd rather not, based on my level of expertise in stepper motor controllers.

Cheers

Rodp2