Mods | Kenwood Tkm-707

The front panel is not intuitive for hams. Download the "Kenwood TKM-707 Ham Translation Sheet" (easily found via Google). It maps "CH" to VFO and "Scan" to memory recall. Once you learn the logic, it’s a joy to use.

Given the age of this equipment and its exposure to marine environments, preventative maintenance modifications are critical to preventing catastrophic component failure. Target Component / Circuit Known Issue Recommended Modification / Repair

Addressing aging components to ensure the longevity of the radio 1.2.2 . Kenwood TKM-707 Mods and Technical Adjustments Modifying the Kenwood Tkm-707 Mods

Any work involving the opening of the chassis must be done with the power fully disconnected. Proper Electrostatic Discharge (ESD) protection is necessary to prevent damaging the microprocessor and integrated circuits.

often involves "service modifications"—preventative measures to address common age-related hardware issues 1.2.2 . The front panel is not intuitive for hams

However, the TKM-707 came out of the box with maritime restrictions. To make it sing on the ham bands, you need to perform a few key modifications.

| Feature | Modification Type | How to Achieve | Result | | :--- | :--- | :--- | :--- | | | Hardware | Clip Diode D312, D313, D314 | Transmit on LSB, USB, and AM across wider frequency range, including ham bands. | | Activate VFO Mode | Hardware + Key Combo | Clip Diode D313, then press C + 84 ENT | Switch from channelized operation to continuous frequency tuning. | | Configure for Ham Use | Hardware | Set DIP switches S301-1: OFF, -2: OFF, -3: ON, -4: ON | Enables full ham band operation with dealer mode and US destination. | | CPU Reset (Clear Memory) | Key Combo | C + Power On | Clears all stored memory channels and performs a full reset. | | CPU Reset (Keep Memory) | Key Combo | ENT + Power On | Resets the CPU but retains programmed memory channels. | | Adjust Power Output | Hardware/Alignment | Internal realignment via service manual. | Potentially boost output from 150W to 180-200W PEP. | | Enable/Disable Key Beeps | Key Combo | C+80 ENT or C+81 ENT | Turn confirmation tones on or off for silent operation. | Once you learn the logic, it’s a joy to use

The TKM-707 has a reputation for slightly muffled receive audio due to aggressive IF filtering meant for noisy boats. The transmit audio is fantastic (the Kenwood "warmth" is there), but you can make it better.

While no publicly available official guide exists for the TKM-707, information from knowledgeable hobbyists suggests the modification involves manipulating an internal DIP switch block ( S301 ):

For decades, the Kenwood TKM-707 has been a stalwart of maritime communication, a rugged and powerful SSB radiotelephone trusted by sailors for its reliability. But this marine radio has found a second life on land, cherished by amateur radio operators for its robust construction, impressive transmit power, and the potential to be molded into a capable ham radio station. Its journey from a vessel's communication center to a ham's shack is made possible through a series of hardware and software modifications known as "mods."

: Provides full circuit descriptions, PLL diagrams, and maintenance procedures. Mods.dk - TKM-707 Section