Kenwood RC-D710 input voltage

[Jay911]

Hi all,
Now that I've finally replaced the control head on my TM-D710A, the older one (which just has some volume/squelch knobs broken) would seem to make an excellent TNC for use with various radios like my Wouxun KG-UV2D, or even a Maxtrac, as hinted at with this document: D710 Display on any HT

The part I'm a little tentative about is the implication on that web page that the control head/TNC only takes 10VDC. My intent was to not use the PG-5J interface unit shown on that page but to make my own cable as shown later on the same page, from just an old RJ45 cable, with leads for power and for RX/TX.

It is looking like providing power of greater than 10V (i.e. a 12V cigarette lighter plug) is unadvisable.

Should i just bite the bullet and get a PG-5J and make my interface cables out of mini-DIN connectors (one for the Wouxun and one for a Maxtrac), or does anyone else have other suggestions?

 

[kb2vxa]

A control head is not a TNC but I see what you're trying to do. Being the voltage regulator chip seems to be in the radio and not the head you'll just have to find out what voltage the other radio feeds it. Head circuitry usually works on 8 volts (10 absolute max) so that base is covered but control functions could be a nightmare not knowing which pin goes to what, all radios are not the same. Then there is the question of how control functions are handled, control voltage ranges and all that, the mystery deepens.

 

[Jay911]

The RC-D710 is both the control head and the full TNC for a TM-D710A radio. It's known to be used as a TNC interface for pretty much any radio you can hook up mic/PTT & speaker connections to - per the link in my first post.

That link indicates that the PG-5J provides "10 volts at about 360 mA" to the CH so I guess I have to either provide that exact power & amperage or get the PG-5J. The latter is seeming like the better solution since it has powerpole connectors and just takes 13.8 in.

 

[AK9R]

Jay, what I don't understand is how does a TM-D710 control head know that it's now an RC-D710 TNC? The link you posted, which is to Bob Bruninga's web site, includes a wiring diagram that shows how he connected to the RJ-45 connector on the TM-D710 head. But the functions of the RJ-45 pins shown in the diagram are completely different from the pin-outs in a TM-D710.

At this point, I suggest you contact Bob directly. His email address is at the top of this page:

APRS: Automatic Packet Reporting System

 

[KE4NYV]

We offer an alternate interface for the D710 head. Our interface uses the popular PowerPole for power connection and our price is lower, too.

http://www.rpc-electronics.com/710interface.php

We have been selling these for about five years now and the feedback has been great!