Help with dead CT6800

[Laserhobbit]

Hi,

I have 3 xCT6800, which all seem dead, one seems to overheat wildly. Does anyone know how hard these are to fix or does anyone fix these? I am also not sure if the amp is working Ok and so even a test with someone else's amp may be useful. It just seems a shame to just skip them.

Many thanks

Steve

[edison]

Steve, Maybe badpip can help you out. He just bought a 6800 set and working amps. I,m not sure if he can help you but it might be worth a shot.

[kecked]

Check to see if the rotor turns freely. If it does next check the fuse on the scanner. It looks like a green resistor. If that is all good you likely have an driver issue. You said that the scanner gets hot. Does the scanner lock into position? If so then check for over damping. See your manual. These things are tanks and I doubt they are bad. It is almost always the fuse or the driver. Contact onestoplaser shop if you need service. I'd send you to pangolin but I doubt Sir Bill has time.

[mixedgas]

Ok there is a IR led and two photodiodes in the base of the scanner. If you have 12V in your projector, that and a 1 Kilo-Ohm (1k0) resistor will just light the position sensor led. You will need the correct polarity on the led leads. You will then see about 50-75 milliVolts or more from each of the position sensors as you move the shaft. As you turn the shaft way, the voltage will go down for one photodiode and up for the other. In the center the voltages will be weak but equal.

The coil should read 4.2 ohms +/- 10%.

Led test wiring goes to "AGC output" and "diode common."

A pinout for the scanner is here:

http://www.camtech.com/products/6800/6800HP-outline.pdf

A "D" flashlight battery (~1.5 volts) applied to the scanner coil for short periods of time should cause the mirror to "FLOP" around. This is very hard on the "D" cell.

Do not accidently short the flashlight battery to the position sensor wiring , a dead galvo may result.

Steve