While the TKM-707 has a "large efficient cooling system," it can still get very warm during long high-power transmissions.
Modifications involving the removal of internal components should only be performed with a Service Manual and proper ESD protection to avoid bricking the radio. ssb radiotelephone - tkm-707 - Manuals (Repeater Builder)
The most sought-after mod for the TKM-707 is the MARS/CAP (Military Auxiliary Radio System) expansion. By default, the TKM-707 is locked to marine frequencies and will not transmit on amateur bands. kenwood tkm707 mods
A known issue in Kenwood digital boards of this era is cold solder connections . Resoldering the main PCB and cleaning the Molex connectors can fix erratic behavior. 4. Cooling System Enhancement
You can fine-tune the beep and alarm tone levels using internal potentiometers (VR7 for beep, VR6 for alarm) if they are too intrusive during operation. 3. Essential Maintenance "Mods" for Reliability While the TKM-707 has a "large efficient cooling
Because these units are decades old, certain "maintenance mods" are required to keep them operational.
This typically involves removing specific surface-mount diodes or 0-ohm resistors on the control board. Professionals often perform this during a full alignment or capacitor replacement service . 2. Audio & Modulation Upgrades By default, the TKM-707 is locked to marine
2. Page 3. MAINTENANCE AND ADJUSTMENT. TKM-707. Adjustment 1-1. Cover removal Before removing the cover, turn the DC power supply' Repeater Builder®
The TKM-707 uses a coin-cell battery to retain memory channels. If your radio resets every time it's powered off, you'll need to replace this battery , which may require soldering.