Help with dead HT1250

WA6PMW · #1 (**permalink**) 03-09-2013, 11:54 AM

I have a low split, UHF HT-1250 that won't power up.
Does anyone have a parts layout pdf or can someone tell me where the
board mounted fuse is ?

spanz · #2 (**permalink**) 03-10-2013, 6:30 AM

On the GP680 european version of the HT1250, the 3 amp surface mounted fuse is on the underside of the board, you have to unscrew board from metal chassis, look close to the +ve battery connector is the small fuse, sometimes blue in colour. The board layout and components vary depending on the age as they changed layout slightly over the years. Hopefully the HT1250 is the same. Marked as F501 on the board.

If the fuse has not blown then sometimes resoldering the volume/on-off pot soldered connectors restores power....sometimes the supply goes bad betwen fuse and on-off switch due to multi layer board connector failure so a wire link between fuse and on-off connector proves this (marked 4 and 5 on image)
Pic attached higlighting the fuse. Hope this helps..

cabletech · #3 (**permalink**) 03-10-2013, 10:33 AM

Are you sure the battery is good?

WA6PMW · #4 (**permalink**) 03-10-2013, 11:46 AM

OK, the fuse is good. I re-soldered the terminals on the on/off switch. I checked and I do have continuity from
the Batt. Term. through the on/off switch. I didn't mention before I have a UHF and a VHF with the same systems. They sat for about a year. When I tried to use them they are both DOA. Tried 4 battery’s each with about 8 volts. Still DOA.

spanz · #5 (**permalink**) 03-10-2013, 1:06 PM

A failed firmware flash upgrade can brick the GP series and when this happens it can give appearance of a dead radio. Very occasionally reflashing the firmware brings them back to life. Again this is based on the similar euro GP6xx series which I believe are essnetially the same as the HT750/HT1250 but with more memory.