On 2018-02-26 11:00 AM, Corby wrote:
Also I usually remove a battery A2 and install two shottky diodes on the
underside of A2s chassis jack.
Non-battery units have an A2 that just has these two diodes on it.
On mine, I didn't bother with schottky diodes, I just used half of a
bridge rectifier that I bolted to the chassis. Removing the battery
charger version of the A2 board also removed a significant amount of
heat from the unit. That board runs quite warm!
Another interesting point about removing the A2 board is that in
addition to freeing up a card slot, it frees up the transformer winding
that was used for the battery charger. Maybe use that to build a 5V
supply for some new add-on. The A2 board was rated for ~25V @150 ma or
~3.75W. At 5V, that's 0.75A. You'd probably have to use a switching
supply. Extra care would be required to make sure that the supply's
switching noise didn't degrade the unit's performance.
Ed
On 2018-02-26 11:00 AM, Corby wrote:
> Also I usually remove a battery A2 and install two shottky diodes on the
> underside of A2s chassis jack.
>
> Non-battery units have an A2 that just has these two diodes on it.
On mine, I didn't bother with schottky diodes, I just used half of a
bridge rectifier that I bolted to the chassis. Removing the battery
charger version of the A2 board also removed a significant amount of
heat from the unit. That board runs quite warm!
Another interesting point about removing the A2 board is that in
addition to freeing up a card slot, it frees up the transformer winding
that was used for the battery charger. Maybe use that to build a 5V
supply for some new add-on. The A2 board was rated for ~25V @150 ma or
~3.75W. At 5V, that's 0.75A. You'd probably have to use a switching
supply. Extra care would be required to make sure that the supply's
switching noise didn't degrade the unit's performance.
Ed
