bc200xlt battery-pack

Hi all,

First post here and sorry to drag up an old thread.
I have a 200xlt that I bought new as a kid and it's still in amazing condition. Of course the battery back needs some attention. I discovered while attempting to charge the nicad pack that after 10 hours it was what I would call extremely hot.
I took it apart as the plan was to replace the cells. Before I went ahead and replaced the cells I wanted to look closer at the charging circuit board in the battery back to see if anything was obviously damaged with the high temp seen earlier. Visually it looked ok, except for the larger blue resistor. The legs of which look dark and corroded. I connected the wall wart and tested the voltage at the regulator. Input voltage from the wall wart is 18vdc, regulator is passing 10vdc to the battery pack. Looks good from what I can tell. I also discovered that the blue resistor may have had a cold solider joint. Unfortunately, and I'll assume from heat the color code is all but gone except what looks like brown as the first color and gold as the last.
So my question is, does anyone know what the value of this resistor is supposed to be? I've searched high and low for a picture or a schematic to figure it out but I've been unsuccessful, and I'd really like to get the old gem working again.
Any help would be greatly appreciated.
Thanks

I moved your post to its own thread.

The Best I Can Tell

I have my original BC200xlt I purchased new back Christmas 1988. I had one old pack here without batteries. I unsoldered the resistor on one end and lifted it up off the board and it reads 27.7 ohms on my digital meter on the 200 ohm scale. Reading the colors on the resistor is a challenge but it looks like red,brown,black,gold. But I am not sure. I took some pictures on my phone if you wish to pm me. Hope this helps. Mike.

Mattm123 said:

Hi all,

...
I took it apart as the plan was to replace the cells.
Any help would be greatly appreciated.....
Thanks

Click to expand...

I hope you are putting in NiMh cells. No need to change anything in the internal circuit.

Ooops?

bb911 said:

I hope you are putting in NiMh cells. No need to change anything in the internal circuit.

Click to expand...

I opened up my pack and the NIMH pack was from the NiCd Lady (since retired). I found a 21 ohm resistor soldered across the original resistor, along with a smaller resistor partially behind both. I couldn't recognize the color of any of its' rings.

Thanks Mike! That helps a ton! I measured this on when I removed it and it's measuring 23 ohms. I'm pretty sure what I'm seeing is a gold band on mine as well. For sake of a few cents I'll replace it.

As for replacement cells I will be using NiMh and they arrived yesterday. 2200mah 1.2 flat top with solider tabs. Should I haven gotten a smaller mah rated cell? My understanding is mah won't cause a higher current draw, just a longer charge time. The cells internal resistance shouldn't change?

Any thought and experiences appreciated.

Thanks everyone for the help. I replaced the resistor with a 1/4w 22 ohm and 6 22mah cells. Scanner works great and the excessive heat problem is gone.