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.
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
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)