[MeidadRaz]

hi all
 
i realy need your help with my HM-801.
Since yesterday suddenly my baterry is not charging and now it is empty so i don't have access to my HM-801.
 
I check my charger with a volt-meter and got on both pins a measurement of -9.0V.
Each pin of the charger connector to the HM-801 has an inside and outside areas, i measured each pin with the positive probe on the outside and the negative probe on the inside of the pin
 
Is there a problem with my charger? i would expect the measurement to be +9v and -9v.
I repeated the measurement several times to verify the results.
 
please help me to identify the source of the problem:
1. is it a problem with my charger?
2. is it a problem with my HM-801 charging circuitry?
3. or is the problem with my battery? (doesn't the device should work with only the charger connected to it?)
 
and one last thing, I think my firmware is V0.21 but i'm not sure. i saw at the head-direct site that this version fixed a bug with the battery charging controller. http://www.head-direct.com/News/?act=detail&id=214
 
can any one elaborate about this bug? can it be the source of my problem.
 
thank you in advance
meidad raz

 

[Edwood]

Sounds like your battery is fine.  You're measuring one of the sets backwards, hence why both readings are -9.0V. 
 
Did you check the output voltages of the AC Adapter itself?
 
Also, take the battery out, and plug in the AC Adapter and see if the HM-801 powers on without the battery.   It should work even without a battery.  If it does not power up, then it's a problem with the AC Adapter or the HM-801 itself.
 
Although since your HM-801 is not powering up with the battery, it's likely the HM-801 itself, since the battery pretty much has a full charge
 
-Ed
 

 

[MeidadRaz]

thanks for the reply.
 
I'm sure i measured both pins the same way, i've rechecked my self several times. If someone can check his charger and verify for me that the voltage on the two pins should be oposite (+9V and -9V) i'll be greatful.
 
for now it seems to me that something went wrong with my charger is the best guess, though i can not explain why or how it can happen the suddenly both pins have the same polarity.
 
I think i will order a new power supply, my other option is sending them both my player and power supply and i don't want to wait that much for the whole process.

 

[Edwood]

Yes, the voltage is differential.  One is +9V the other is -9V.
 
The battery pack is the same way.  It's actually two batteries inside. Hence the 4 contacts.