Hi guys ,i have a dmr ex77 works ok but no display on its front panel,does   it have a fault or is it a firmware upgrade that will fix it,thanks in advance for your answers,russell.

You'll almost certainly find it's an o/c picofuse, possibly on the power supply board. It'll be pale brown in colour. Look for large print on circuit boards pointing to it, something along the lines
"FP401 400mA". It's common in the Panasonics.

thanks Bill,will have a closer look,have just discoverd that it has no tv signal and has had a drink of coke,causing some isolated corrosion.