Remote Telescope Appliance

Control and operation for remote telescope's support devices

Similar projects worth following
This unit integrates several support hardware items for operation of a remotely operated telescope.
The functions the device performs are:
1) supplies filtered DC power for the telescope mount
2) controls two unipolar, 5 wire steppers motors
3) provides a charger output for a DSLR camera battery
4) supplies +5Vdc for powered USB hub
5) accepts two, I2C LM75 temperature sensors
6) accepts one, DHT22 single wire humidity temperature sensor
7) provides proportionally controlled 15V Dew heater outputs based on humidity and temperature
8) supplies two +15Vdc/30W outputs for camera thermoelectric coolers

Control of the various functions is managed using and Arduino Mega and Nano.   Control of each function is split between the Mega and Nano.   

NanoAssySchematic-ScopeV5 01-15-19 pg7-7.pdf

Page 7 of the entire project. The Arduino Nano circuit card assembly. Since this portion will of the project will exclusively communicate with an ASCOM driver, it has its own dedicated USB interface. The Arduino Mega has its own USB interface. The hardware component count is kept low, with the help of code. The Arduino stepper library is used to energize the appropriately coils. N channel FETs with logic level Vgs thresholds are used to individually energize the stepper coils, keeping the part count and stepper driver cost low. In the code, to reduce coil heating when not moving, the digital outputs drive each gate low sending each FET to an open drain state. When a movement command is received, the gates are returned to their previous state before using the stepper library.

Adobe Portable Document Format - 30.84 kB - 01/25/2019 at 13:14



Functional block diagram

Adobe Portable Document Format - 26.55 kB - 01/18/2019 at 00:39


  • 1 × Arduino MEGA 2560 REV3
  • 1 × Arduino Nano V3.0 ATmega328P
  • 1 × MOSFET P-CH 60V 12A IPAK ON Semiconductor NTD2955-1G
  • 14 × MOSFET N-CH 60V 11A I-PAK ON Semiconductor RFD3055LE
  • 7 × IC CURRENT MONITOR SOT23-5 Microchip Technology HV7801K1-G

View all 9 components

  • Build done, Initial checkout

    Paul Hitchcock01/25/2019 at 12:26 0 comments

    Units done and performing initial checkouts.  Since most functions need an Arduino to function, there is a parallel effort to write and debug code.

    The Nano which supports that will support ASCOM control is functional.  The ASCOM driver has yet to be written.

View project log

Enjoy this project?



roberto wrote 06/09/2023 at 21:56 point

Hello friends. I have a project created with relays, voltage sensors, and an Arduino Nano. In this project, I use the sensors to monitor the voltage range, and if it goes out of range, the relay disconnects.

I would like to integrate it into your system, but instead of using relays, it would be better to use MOSFETs because they are smaller in size.

  Are you sure? yes | no

Paul Hitchcock wrote 01/18/2019 at 02:04 point

Oh it is a lot.  and a lot of documentation. 

This is my third one, the first and second units had limited expansion and functionality.  This one incorporates the functions from the previous two.  I wanted to ensure this one had a little extra growth.  

  Are you sure? yes | no

Dan Maloney wrote 01/14/2019 at 19:30 point

That's quite a collection of connectors! Hope we get to see what they all go to -- looks wonderfully complicated.

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates