Hello,
I have a Losmandy G11 Gemini 1 v4 (updated) mount bought back in 2001. It¡¯s the version with the RJ45 motor sockets. Until now I have not attempted to use the autoguiding RJ12 port but would like to get it working and invest in a cooled camera.
According to the Gemini manual, the Common pin 2 has +5V on it rather than 0V of the ST-4 standard, but in both cases to activate the drive you connect one of the direction pins to the Common pin. I have verified that the +5V is present on Common.
I currently have the mount indoors on a table. For a completely different reason I have made a simple hand controller consisting of four directional switches that connect the Common to each of the direction pins and I thought I could use this to test the autoguiding port. I also have a RJ12 tester box with 6 LEDS that light if +5V is detected. Using a ¡®Y¡¯ splitter in the autoguiding port, I have plugged in both. The Common pin LED lights and pressing each of the other switches lights the appropriate LED.
In the Setup menu, I have set sidereal tracking rate, photo mode (repeated with All Speeds) as the manual says and also a guiding speed of x0.8.
If I hold down one of the DEC switches for a long time, I see no indication on the motor/worm that it is turning. Also, the manual says that if I hold down the opposite direction switch at the same time, there should be an ¡®Autoguiding error¡¯ on the display (deluxe hand controller). I don¡¯t see this message ¨C the display is just blank. This makes me think the autoguiding port is not working. So here are some questions that I hope someone can help with:
1)????? Can I test the autoguiding port in this way? Does it only respond to short correction pulses rather than a continuous signal?
2)????? Am I missing something in the menu settings?
Assuming I get it working at some stage there are a couple of other questions:
3)????? Do all cameras with a ST-4 port have opto-isolator outputs with open collectors? (I realise that I will need some kind of inverter to connect to the Gemini).
4)????? Some cameras only have a USB. Do cables exist that are USB at one end and ST-4 at the other end and suitable for guiding from the camera or direct from a computer.
Thanks very much for any help you can give.
