Remove circuit board

You didn't say whether the radio still worked ok apart from the noise...

Defective components can produce such noise as can a dry soldered joint - a dry joint is a fairly common fault.

A white type noise is typical of many types of receiver when the squelch is turned down. The squelch circuit is designed to reject signals that are too weak to receive with sufficient strength to be intelligible and in doing so also blocks the background "static". On many CB and VHF type receivers the squelch level is adjustable but tends to be either preset or automatic on basic walkie-talkie type radios. Perhaps the squelch requires adjustment or perhaps the circuit has stopped working.

[PDF]Page 1 INSTRUCTION MANUAL KENWOOD ...

manual.kenwood.com/files/B62-0790-10.pdf

o Contains 60 memory channels programmable with desired frequencies and ... o Do not modify this transceiver unless instructed by this manual or by ... BASIC TRANSCEIVER MODES . ..... 1 Press [VFO] to select VFO mode. P1'I switch, and ...

[PDF]INSTRUCTION MANUAL - Kenwood

manual.kenwood.com/files/TH-D7-English.pdf

memory channel to be named using up to 8 ... Do not modify this transceiver unless instructed by ...... In VFO or Memory Recall mode, use the keypad to select a ...

Modifying the Kenwood TH-78a handheld transciever

www.welcomehome.org/rainbow/.../kenwood/kenwood-th78-mods.html

Nov 17, 1995 - (When William's early-model TH-78 was upgraded his mods (removed .... channel (if in memory recall mode) or last frequency (if in VFO mode).Missing: th234

1 try to check the volume button is not fouled.
2 try to do reset by the manufacturer. (With station stopped ,pressing the two buttons on the side station . Starts station for 2 sec. Releases the side buttons.
3 try to do the firmware update.

I am not familiar with the radio but check the squelch and be sure somebody is transmitting.

1 is the least amount of squelch and 9 is the most. 9 requires more ratio power to break the squelch than 1.

I have a schematic diagram of your unit. There are lots of pictures for you to follow on how to re-soldered your device.

Please just click HERE so that you can be in the right page.

I hope you find it very helpful.

Probably not the squelch but the speaker on the VHF. These radios are famous for crapping out when getting wet.
Try listening to the weather radio VHF ch 01, 02, or 03. depending on your location and play with squelch.. Keep in mind they do make external speakers you can hook up.

my manual ka sa kenwood th 234

first of all check the volume control see if a wire broke off. but i suspect a cold solder joint on that volume control switch. if not check the board for a small crack.

http://www.mods.dk/downloadmanual.php?RefFil=TH-234_235_Service_manual.zip&radio=

Try here,