I recently purchased a Kenwood TK-380 UHF handheld radio on eBay. This is a commercial UHF FM transceiver used by public safety organizations. It will do 4W output, narrow or wide band transmission, and conventional or trunking operation.
This radio is Part-90 accepted, which means it can only be programmed via computer. Unlike commercial ham radios, regular radios are not allowed to provide the user with a means to set an arbitrary frequency from the front panel. This radio has that functionality, but it is disabled by default. By removing a surface-mount resistor jumper inside the radio, you can re-enable it.
Start by removing the battery and antenna, and then remove the two screws at the bottom of the battery compartment. This will allow you to separate the casing from the radio body, which should look something like this:
Next, remove the rubber gasket and speaker assembly by peeling it off the body and disconnecting the speaker wires:
Next, remove the top logic board with the display and the button pads. It is not necessary to disconnect the ribbon cables going to the board below.
Next, remove the bottom board’s screws and flip the board over. Note the resistor marked R144:
Remove this resistor. This can be done by desoldering it with a fine tipped soldering pencil or by force using tweezers to crush and remove it:
When you’re done, reassemble the radio, taking care to realign the rubber button caps in the front panel. Next, you must use the software to enable the self-programming mode in the radio. Once you do, you can hold down the button below the PTT button while turning the radio on to enter “SELF-PROG” mode. Navigating with the buttons on the radio is rather self-explanatory after that. Full-size images are located in the gallery.