When the marine industry shifted toward satellite communication and VHF, these robust SSB transceivers hit the surplus market at bargain prices. Enter the world of . With a few strategic hardware and software tweaks, you can transform this marine radio into a formidable ham radio shack workhorse.
| Issue | Likely Cause | Solution | | :--- | :--- | :--- | | | You removed the wrong diode. The CPU lost its band table. | Re-install original diodes. Refer to service manual for default config. | | No TX on 10m (28 MHz) | Radio’s LPF board doesn’t include 28 MHz by default. | You need to swap relays on the LPF board or add a 28 MHz external LPF. | | LSB sounds "Donald Duck" (pitchy) | The crystal mod isn’t frequency accurate. | Adjust the trimmer capacitor on the LSB crystal circuit. | | Display dim or flickering | Stock EL backlight failing. | Replace with LED strip mod (12V white LED strip cut to size). | | No output power | Dirty relay on the LPF board. | Tap relay RL1 gently with a screwdriver handle. Desolder and clean if persistent. | Part 8: Conclusion – Is the TKM-707 Worth Modding in 2025? Absolutely. You can buy a used TKM-707 for $200–$300. After the frequency expansion mod , you have a 150W SSB radio with a receiver that rivals the Icom IC-7300 in terms of dynamic range (the TKM-707 uses a double-conversion superheterodyne with a RF MOSFET preamp). Kenwood Tkm-707 Mods
After performing your mods, always test into a dummy load first. Never modify for 11m (CB) operation—it’s illegal, and the radio will bleed harmonics across entire bands. Keep it clean, keep it ham, and enjoy the sleeper classic. Have you performed a unique mod on your TKM-707? Let the community know in the comments below. | Issue | Likely Cause | Solution |