Bren-Tronics Inc. has redesigned the internal electronic circuitry to the BB-2590 which does not allow early models of McDowell Research MRC-85 and MRC-86 chargers to charge the battery. McDowell Research has developed upgrade kits to our MRC-85 and MRC-86 chargers that will allow our chargers to charge the redesigned battery. The following upgrade kits are now available:

MRC-7020-1 for the MRC-85

MRC-7020-2 for the MRC-86


Affected Chargers:

MRC-85:
Chargers with serial numbers below 1900 DO NOT charge the new battery and require upgrade kits in order to charge the new battery.

Serial numbers 1900-2199 need to be checked for charging board circuitry Revision "C". If boards are not Revision "C", the charger requires upgrade kit. If the circuit boards are Revision "C", the charger will charge the new battery.

Serial numbers 2200 and above have the Revision "C" charging circuitry and will charge the new battery.

MRC-86:
Chargers with serial numbers below 1300 DO NOT charge the new battery and require upgrade kits in order to charge the new battery.

Serial numbers 1300-1499 need to be checked for charging board circuitry Revision "C". If boards are not Revision "C", the charger requires upgrade kit. If the circuit boards are Revision "C", the charger will charge the new battery.

Serial numbers 1500 and above have the Revision "C" charging circuitry and will charge the new battery.

Checking the MRC-85 boards for Revision "C" charging circuitry:

1. Remove twelve (12) screws holding control panel in place.


2. Remove control panel and place face down on a flat surface.


3. Inspect the component side around the edges of the board on all 6 charger boards for "MRC4020-02-01C". If the "C" is any other letter then order and install upgrade modules.

1. Remove six (6) screws holding control panel in place.


2. Remove control panel and place face down on a flat surface.


3. Inspect the component side around the edges of the board on both charger boards for "MRC4020-02-01C". If the "C" is any other letter then order and install upgrade modules.