TH-D74 Modification of the US version

TH-D74 Modification of the US version

There have been numerous questions on the internet regarding whether the published and well detailed modification by TH-D74 Mod Extended TX Frequency is applicable to the US version of the TH-D74(A).

The usual disclaimers apply.  Please do at your own risk, and follow the laws of your country.

Removal of R761 will open up wide band transmit on the US TH-D74A:

• 136-174 MHz
• 216-235 MHz
• 410-470 MHz

Auto Repeater Shift will still function.  The Kenwood Programming Software will still work, as does the RT Systems Programming Software.

Note on the modification:  I have seen YouTube videos on the net that make this modification seem complicated, if not downright dangerous.

My experience is as follows:

Be sure to back up all programming with either program noted above.

Referring to the well detailed modification instructions of TH-D74 Mod Extended TX Frequency, I did the work on an antistatic pad, and used a magnifying headset. 

I did not disconnect the ribbon cable as noted in step 10.  Laying out the radio as seen in step 10, I used a temperature controlled soldering iron and heated the body of the resistor to soften any glue.  I then heated the left solder pad, and then quickly moved to the right solder pad, and heated it with a slightly uplifting motion.  The resistor came off easily. 

Looking with higher magnification, no solder bridges were noted.  The unit was reassembled, and a full reset was done.  The modification worked well, checked with a dummy load.

Frequency data was reloaded into the radio, and the unit has functioned well since.