The Radio Information Board

Like the subject says, does anyone have either written information or a schematic of said cable that can be provided?

TIA for your help!

is it the one that uses the RJ45 jack to interface w/ the radio?
I have a schematic for it that works well and is cheap to make.

The KPG43 is used for programming the TK690/790/890 series. Assuming they are programmed through the mic connector, the connector is round with 14 compression-type contacts and has a special long shank screw to fix it to the mobile radio's front panel.

I dont know about the pinouts for that one but it should work with my design.
Ill draw it up later when I have some time.

You are right, it program's through the mic connector. Many of the lines on the mic connector are on the 25 pin D on the back of the radio. I'm hoping to be able to program it through that.

Let me know if you find a schematic.

I bet you could program it through the back. I am pretty sure that all Kenwood does is use a MAX232 equivalent to convert the serial +/- 12v to TTL for the radio. However I don't know if any other pins other than TXD and RXD are required.

Birken

Sounds like you may be right, Birken....however, I don't have the service manual so I don't have any way of knowing which pins are TxD, RxD, and ground....can anyone with a service manual for the TK890 help here?

Unfortunately, it is more than just a MAX232. There several transistors on the board, all surface mount. I have no idea how to ID SMDs, so have no way to what the specs of them are. If I could do that, I would have no problem making a schematic like I have posted on the board of the KPG22 / 4, as well as the Maxon SMP-4004C and one of Midland's cables. Can anyone help me with id'ing those transistors?

Can you take a high enough resolution photo to be able to read the parts? I might be able to help ID them.

Well, I can certainly try. Give me an email addy I can send the pics to and I'll see what I can do.

Pics sent!

did you get any more info on this ?

i am looking for what pin carries the RXD on the mic connector ?


pin 6 is the TXD - I just need the RXD line

I don't know right off. Give me a few days, and I'll see if I can't find out.

Ozindfw, did you ever get anywhere with the parts ID?

looks like TRD means transmit and receive data -

the 690 shares data on pin 6 TRD

so you need a data combiner schematic - probably a resistor and a transistor etc -

a kpg-43 schematic would be great


thanks for any help

If pin 6 is labeled 'TRD', then that's exactly what it is, 'transmit/receive data'. If I can find it (chances aren't good, I'm a disoraganized slob), I have part of the schematic of a Kenwood remote mount radio that uses such a circuit to convert the standard two-line TXD/RXD circuit from the µprocessor to a single-line TRD circuit for the comms between the head and drawer. If I can find it, I'll send you a schematic of the relevant portion of the circuit. I want to try to use the circuit in question to make a TK-350 a 'remote head' (I know it sounds crazy, but find the thread on the board about the subject, and it will make a little more sense ).