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Seletek - Armadillo - Platypus,
Control cooling fans and dew heaters

(based on relays)

With the utility program "PinByPin", control of the outputs of the Seletek goes one step further. For a description of the abilities of the program, please follow this link, here we will explain how to connect the cooler fans and / or some relays for heavy dew heater bands or controllers.


For the current "2" version of the controllers, Armadillo2 and Platypus2,  all ports have female DB9 sockets, with pins 1 to 4 active - exactly the same as the Main port described here

The Seletek family of controllers be it the original Seletek, or the new Armadillo), have two DB9 connectors, each one of them with 4 power outputs. The outputs of each connector work in group, commanding a stepper motor in the most typical application (for automatic focusing or operating a filter wheel) but can also be used for other purposes.

For the MAIN port, the power outputs are pins 1 to 4, while for the EXP ports they are pins 2 to 5. Both ports have ground at the shell.

If you want to control, say, 1 cooler fans and 2 relays to switch on/off dew heater bands (you could also use a relay to switch a dew heater controller), a possible configuration, using the EXP port, could be:

•    Pin 2: power for fan

•    Pin 4: power for one relay

•    Pin 5: power for the other relay

•    Shell: common ground for the 3 items

Lunatico Astronomia

... so just a few wires and a DB9 connector (female for mating the EXP port, male for the Main one), and using the PinByPin program you can remotely or automatically (depending on delta temperature readings) control if your main mirror should be cooled or the corrector lens protected against dew!


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