Charger for HT750/GP340 series - green light after 1 minute

g8tzl2004 · Post by **g8tzl2004** » Sun May 21, 2006 8:16 am

I have recently acquired a fast charger for the HT750/HT1250/GP340 series handheld - model number HTN9000B

After about 1 minute , the charger switches from the "steady red" to the "steady green" (fully charged) LED.

I suspect the fault could be in the sense circuit. I tried a known duff battery and I get the "flashing red" (unrechargable) LED , so the charger seems to be able to sense a duff battery.

I measured the voltage across a good battery when it is inserted into the charger. The voltage gradually increases to around 10v , at which level the green LED comes on. Every few minutes , I think I can hear a low level "buzz" which lasts 0.5 seconds coming from the charger!!

I think this could be a common fault with the charger - any idea what the fault is and how to fix it?

Thanks

g8tzl2004 · Post by **g8tzl2004** » Mon May 22, 2006 8:50 am

Any thoughts on why the charger goes green after 1 minute?

Thanks

Post by **wavetar** » Mon May 22, 2006 3:47 pm

I'm assuming you've tried multiple known good batteries with the same result. I've seen several cases of the A/C adaptor going bad...only putting out 15-18 volts with no load when it should be closer to 22...cause your problem.

Todd