Yaesu FT-7800 has never let me down. But in recent months, the MH-48's PTT wire has begun to deteriorate. I ordered the MH-48 PTT microphone cable through eBay and had it replaced (repaired).

Description of the problem

The thin sheath of the cable was cracked lengthwise.

The inner part of the cable protrudes out of the sheath.

At the point where the cable is connected to the radio station, where the 6P6C connector is installed, the cable separates from the connector and is close to breaking.

Buying a replacement cable

A purchase on eBay takes place with PayPal, which was linked to my plastic card earlier. The order was successfully delivered to my Russian Post office. For information -wire costs about 500 rubles, and a new PTT - from 1200 rubles.

New cable for MH-48:

Repair tool

I needed a Phillips screwdriver - I bought a set Hammer Flex 601-036

Opening the MH-48 PTT

You need to unscrew 3 screws.

Then the body opens from above into two halves.

Finally, the plastic pedal is removed, which presses when the PTT button is pressed on the micro switch of the PTT button ("Push to Talk").

Yaesu MH-48 PTT main board (click to enlarge).

Cable replacement

Disconnected the wire connector from the connector on the board.

Pinout of the old MH-48 PTT cable:

Pinout of the new MH-48 cable.

I connected the new cable to the connector and closed the PTT switch.

Tightened the screws - self-tapping screws.

Problem when assembling the PTT and its solution

If one of the screws is lost, it can be “obtained” from other devices. For example,
I unscrewed it from a portable flashlight that I had previously purchased at a hardware store.

As you can see, the thread pitch is the same. The silver self-tapping screw is not original.

Result

Checking the PTT after assembly: the number buttons work as before. Checking the radio station for transmission on the WebSDR frequency showed that there is modulation and the microphone is working.

Related publications

Control the transmission of a radio station via the COM port using RTS or DTR signals

Installing Chirp Next on an antiX bootable USB flash drive

WSJTX_improved 2.7.1 user manual

Electronic telegraph key Ultra PicoKeyer from HamGadgets

CW macros for FLdigi