Ferguson FM and DAB Digital Radio Cracked Solder

This Ferguson FM/dab radio model FRG-120D was manufactured about 2004. The radio exhibited a blank screen with its backlight on. Sometimes the radio would work (FM more than digital dab). the performance was the same with battery or mains. This problem got worse over they years.

On disassembly (easy), i noticed the movement of the ribbon cable could cause the LCD display to work occasionally, so I knew there was a bad connection somewhere.

Inspection of the ribbon cable connector using a x10 hand lens and good lighting (sunshine in my case) showed solder cracking around the meniscus of the solder. Cracking was mostly at the edges of the 13 core ribbon. These cracks were repaired the standard way by remelting the solder with a hot soldering iron and a little flux. Then all worked well.

Normally solder cracking occurs on the pins of hot component (thermal fatigue), but here I think it was due to the ribbon cable being too short and a clamped-on heavy ferrite ring putting stress on the connection especially when the radio was moved around (mechanical fatigue).