
HT600, P200 and MT1000 quick charge battery information
10/99 by skipp may nospam4me@juno.com

Hello there,

This package contains three different format copies 
of the HT600, P200 and MT1000 internal rapid charge 
battery circuit. Presented in saved bitmap (bmp), 
gif and pdf files from a scan of my original hand 
drawn diagram. 

I had a batch of bad HT600 batteries that I cut open 
to see what's going on inside. 

There are 8 long AA similar type 1.25 vdc Ni-Cad 
cells in series. Four foil contacts on the rear and 
two on the top of battery. 

Details:  Inside finds the batteries soldered to the 
bottom of the pack on the flex foil circuit board. 
There is a thermistor on the negative battery lead to 
pin one of the back plane connector, the battery at 
pin 2 directly. The value drops from around 10K at 
room temp to much less with heat. Probably used to 
indicate battery heating near the end of the charging 
cycle. The negative lead on pin 2 is routed to the 
radio negative supply pad on the top of the pack.

A surface mount chip component is soldered from pin 2 
to pin 3. This chip part has a resistance of 3.3K ohms. 

The positive lead from the Ni-Cad pack is routed via a 
flex foil from the bottom to the top of the pack, then 
soldered to the radio supply positive pad.

Pin 4 of the rear panel contact pads is routed via flex 
foil to the top of the battery. A semiconductor is in 
series with the foil to terminate on the radio supply 
positive pad. Probably for reverse polarity protection.
There also appears to be a small chip cap in series 
with the semiconductor.

Email me if you have questions.

enjoy
skipp