HaulinAshe
Well-known member
I love what the Starcom PTT-03 (Push-To-Talk with VOX disable) switch does for the unit's functionality. I hate the physical dimensions and Gawdawful cable it comes with.
Starcom obviously starts with a standard S-Video cable, whacks off one end and then wires it to their little box that contains the monster push-button switch and resistor. The whole thing is just... BIG, and if you have the comm unit mounted up front somewhere, the cable is WAY too long and bulky.
Since no alternative is available from Starcom, I decided to reverse engineer the thing and make something more to my liking. Thought somebody else might want to do the same. What I found was that the PTT uses a MiniDIN-4 connector (S-video style) to attach to the comm unit. Two pins are for the N.O. (normally-open) push-button switch and two pins are for the resistor that disables the VOX function. A little VOM meter reading and here's the results:
Pins 1 & 2 - N.O. Push-button switch
Pins 3 & 4 - 1k ohm resistor ***EDIT-New resistor value based on Fred_W research.
With my previous Chatterbox comm unit, I had removed the PTT switch from its wrist band and mounted it to the clutch-side grip assembly using some black RTV Silicone adhesive. It's a nice little switch unit. I decided to adapt it to the Starcomm. You shouldn't have much trouble adapting something similar of your liking.
All you need is an S-video cable with one end connected to your switch of choice. Pins 1-2 go to the switch. You can either wire Pins 3-4 to a small (1/8 or 1/4 watt) resistor at the switch end, or if making your own cable (using wire and a replacement connector), you can wire the resistor directly to the connector pins on the comm unit end of things.
Here's a link to the Chatterbox PTT switch that I used. $14 for the switch and about $7 in parts from Radio Shack will do the job.
Chatterbox PTT replacement switch at RideGear.com
Radio Shack did not have a 2.7k ohm resistor, so I elected to use a 2.2k and two(2) 220 ohm resistors all wired in series. I simply opened up the Chatterbox switch, drilled some extra holes in the pc board to make places to thread the resistor leads, and soldered the whole thing up on that end.
The PTT function is now much more ergonomically appealing and there is no mass of bundled wire to deal with. Me likey a lot!!!
MiniDIN-4 connector plugged into Starcomm at left. Modified Chatterbox PTT at right.
MiniDIN-4 pin diagram.
Starcom obviously starts with a standard S-Video cable, whacks off one end and then wires it to their little box that contains the monster push-button switch and resistor. The whole thing is just... BIG, and if you have the comm unit mounted up front somewhere, the cable is WAY too long and bulky.
Since no alternative is available from Starcom, I decided to reverse engineer the thing and make something more to my liking. Thought somebody else might want to do the same. What I found was that the PTT uses a MiniDIN-4 connector (S-video style) to attach to the comm unit. Two pins are for the N.O. (normally-open) push-button switch and two pins are for the resistor that disables the VOX function. A little VOM meter reading and here's the results:
Pins 1 & 2 - N.O. Push-button switch
Pins 3 & 4 - 1k ohm resistor ***EDIT-New resistor value based on Fred_W research.
With my previous Chatterbox comm unit, I had removed the PTT switch from its wrist band and mounted it to the clutch-side grip assembly using some black RTV Silicone adhesive. It's a nice little switch unit. I decided to adapt it to the Starcomm. You shouldn't have much trouble adapting something similar of your liking.
All you need is an S-video cable with one end connected to your switch of choice. Pins 1-2 go to the switch. You can either wire Pins 3-4 to a small (1/8 or 1/4 watt) resistor at the switch end, or if making your own cable (using wire and a replacement connector), you can wire the resistor directly to the connector pins on the comm unit end of things.
Here's a link to the Chatterbox PTT switch that I used. $14 for the switch and about $7 in parts from Radio Shack will do the job.
Chatterbox PTT replacement switch at RideGear.com
Radio Shack did not have a 2.7k ohm resistor, so I elected to use a 2.2k and two(2) 220 ohm resistors all wired in series. I simply opened up the Chatterbox switch, drilled some extra holes in the pc board to make places to thread the resistor leads, and soldered the whole thing up on that end.
The PTT function is now much more ergonomically appealing and there is no mass of bundled wire to deal with. Me likey a lot!!!
MiniDIN-4 connector plugged into Starcomm at left. Modified Chatterbox PTT at right.
MiniDIN-4 pin diagram.
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