OTHER Modifying a V-Box for an optical sensor


SatelliteGuys Pro
Original poster
Feb 17, 2010
Between the North and South Pole
I am starting to rebuild the motor on my H to H mount, which only has an optical counter. I would like to eventually use a V-Box with this, which as you know, only supports a reed sensor.

Is it possible to add optical capacity to a V-Box? I am hoping that it is as easy as adding a 12v DC output.
I don't have a V-Box but dug up a schematic for one. Seems that there are different variants. If you have an input at the pulse terminals like the attachment, it should be pretty easy. Do a voltage measurement.
On my ASC-1 I use a Crydom CMX60D10 SSR. The output of it is tied to the sensor input of the ASC-1 and acts as a switch closure when the input of the SSR sees a voltage greater than 3 VDC.

I'm using a unipolar hall switch and 20 ppr magnet wheel but an optical sensor will work just fine.
Not sure if your optical sensor is a sink or source (PNP or NPN) type but either way no biggie really.
All you need to do is tap into a suitable power source that the optical sensor is designed to work with.
And in range of input voltage of the SSR.
I see the V-Box only has motor and sensor terminals so a good old junk drawer wall wart would work just fine to power the optical sensor.
Hopefully you have a multimeter. You need to get DC voltage into the + and ground of the optical and complete a circuit to the SSR input with at least 3 VDC on the sensor lead and ground of the optical.
Easier done than said. Seriously.

I chose an SSR because I have a box of them and there is no contact bounce as may be in a dry contact relay to generate pulse glitching. Your optical sensor should have a Schmitt trigger. In other words if you operated it static and blocked and uncovered the beam slowly while looking at your meter. It should snap off and snap back on. Instead of what you would see if you put your hand in front of a flashlight beam.
That's a good thing.

If you're handy and this makes sense and need more help. Toss me a beer.


  • VBox_Encoder.jpg
    77.1 KB · Views: 109
  • Like
Reactions: stecle
Thank you for the excellent detailed reply. I checked around for a SSR and they are around $75. :eek

Ebay. Definitely. Doesn't have to be a Crydom. 3-10 or so control voltage input and DC Output load in a low voltage range.
A test first would be cool. Put 5 volts on the ground and + wires. Test for + 5 VDC on 0 VDC on the output wire and ground when you block and uncover the beam.
What brand of sensor is it if it has markings?
If it's something you want to tackle I could jot down a schematic and possibly toss an SSR in the mail. You buy the beer. Any like this will work. As long as voltages and current draw are in range they last forever.


[Sonicview] Sonicview SV-4000 Editor?

AMIKO Amiko Mini 4k uhd s2 x - strengths & weaknesses

Users Who Are Viewing This Thread (Total: 0, Members: 0, Guests: 0)

Who Read This Thread (Total Members: 3)