JMI PC Focus Control

JMI PC Focus Control
Item # JM-PCFC
2 Questions(s)

Waiting List

  • Control a DC focuser motor (sold separately) from your PC through a USB port.
  • The JMI PC Focus Control replaces regular hand unit with control from a computer using a mouse, and gives greater control of speed and duration of movement than a regular hand unit.
  • It can control MOTOFOCUS, MOTODEC, NGF, RCF and other motors.
  • With JMI PC Focus Control no batteries are required.
  • There is no encoder feedback or positional display with PCFC.


What is PC Focus Control?

PC Focus Control (PCFC) replaces your focuser hand unit with precise motor control from the USB port of a Personal Computer (PC). You can use the free downloadable JMI Windows-based software or any ASCOM-compatible software. Testing shows that PCFC gives much greater control than a normal hand unit and JMI was able to get 0.0004" drawtube movement. There is no encoder feedback or positional display with PCFC. PC focus control with encoder feedback can be achieved with optional Smart Focus.

Software Console Controls...

  • Pulse-width modulation (PWM) Frequency Adjustment
  • Motor Speed Adjustment
  • Pulse Time Interval Adjustment
  • Continuous Motor Operation in Forward or Reverse
  • Mouse Controlled Time Interval Motor Operation in Forward or Reverse
  • Specified Pulse Time Interval Motor Operation in Forward or Reverse


  • 5-12 volt DC motor (works best with 5V motor)
  • Motor cable with 1/8" (3.5mm) mono plug on the PC Focus Control end
  • Windows 98 Second Edition / 2000 / XP
  • USB version 1.1 or greater (NOTE: Win98SE may need to be upgraded)
  • Human Interface Device driver (HID) usually included with the operating system
JMI Product Number: PCFC
Additional Information

Additional Information

Manufacturer JMI
Focuser Design No
Focuser or Mask Size 2" Drawtube
Focus Control Digital
Warranty 1 Year Warranty
Included Items

Included Items

  • Control Box with Integrated USB Cable (3')
  • 1/8" (3.5mm) Motor Jack (the unit is powered by the USB port)
  • Software (Free Download from JMI website)
  • Operator's Manual
Questions & Answers

Product Questions

Will this work with a Meade Zero Image Shift focuser?
I have an older JMI motor focus for my 12" SCT and I was wondering if this unit, in place of the hand control, would allow for autofocusing using something like FocusMax for Maximdl? I'd hate to replace my entire focuser if this will work for autofocus.
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