[Kenwood] Re: TM 742

[Clif Holland]

Ok, I will talk you thru this.

1. Remove the covers on the radio.
2. Remove the control head and the cover it mounts to.
3. Remove the screws on each side and remove all the band units.
4. This leaves the 2 control boards and the front chassis.
5. Unscrew the control boards from the chassis and remove them together.
6. Look at the boards as they were in the radio and you will see a cluster
of
   19 electrolytic caps on the vertical board.
7. Under the right side of the caps are a large surface mount resistor and a
    large surface mount transistor.
8. Resolder both ends of the resistor and then the transistor. Make sure the
    solder flows under the tab of the transistor.
9. Reassemble.

Usually what happens is the resistor overheats and loses contact. This
resistor/transistor pair provide 13.8v to the 2(3) modules after the radio
is turned on. When they don't work the control unit doesn't know it and
shows frequency and indicates TX but no rx or TX actually occurs.

Clif Holland,  KA5IPF
AVVid
Authorized Kenwood and Icom Service
www.avvid.com
1-800-214-5779
972-554-6801
----- Original Message -----
From: "carl" <cdr@smce.com>
To: "'Clif Holland'" <clif@avvid.com>; <cdr@pandora.be>
Sent: Monday, December 30, 2002 1:01 PM
Subject: RE: TM 742


> no, only the schematic origin in the box.
> any sugestion what the problem kould be??
> have you them elektronicley??
>
>
> Carl on1abh
>
>
>
> -----Oorspronkelijk bericht-----
> Van: Clif Holland [mailto:clif@avvid.com]
> Verzonden: maandag 30 december 2002 19:48
> Aan: cdr@pandora.be
> Onderwerp: TM 742
>
>
> Do you have a service manual to help you find parts on the board???
>
> Clif Holland,  KA5IPF
> AVVid
> Authorized Kenwood and Icom Service
> www.avvid.com
> 1-800-214-5779
> 972-554-6801
>