Hi Guys!

I have done a similar work to the LinnDrum's power supply PCB.
A couple of months ago I got a Linn with leaked batteries already
damaging the PCB.

So I decided not do solder them directly to the PCB again.
I bought battery-holders vom RS components (www.rsonline.co.uk)
,Stock code 489-891, and mounted them directly to the PCB.

If the batteries are dying again I just buy some and replace
it directly without touching any solder pencil.

I populated the sockets with industrial 600mAh cells.
There is a 1K resistor which charges the batteries far too weak.
I replaced it with 100 Ohms.

With a RAM voltage of 5.3 volts and a battery voltage of 4 volts
during recharge this will charge the batteries within 60 hours from
empty to full, means it will prevent them from overloading.

So if the unit is not used for longer time it is necessary to
switch it on for 3 days every 3..5 month.

If you like I will place a photo of my work here.

If there was more time I would have replaced and redesigned the
entire power supply board with a -dU chargeer which recharges the
batteries quickly in max. 3..4 hours, but at the time this seems
to be too much effort for this machine.

BTW: Your description here is 100% right.
The negative poles of the batteries have to be right.
This is for the power supply board poulated with
the Lambda TO3 heatsinked metal can voltage regulator.

There are others which use a National Semiconductor
TO3 voltage regulator. They may be different.

For any questions please write to quantenspalter@...
or quantumsplitter@....

--- In Linndrum@yahoogroups.com, "Dave" <djretro83@...> wrote:
>
> Alex, you are absolutely correct. When replacing the batteries
ALL of the POSITIVE sides
> should be facing LEFT and the NEGATIVES face RIGHT. Bruce told me
that all of the early
> LinnDrums used to have a battery holder that went + - + and then
they switched to
> soldering it directly.
> Again, the battery placement is:
>
> +****************-
>
> +****************-
>
> +****************-
>
> I've also switched the one battery in my own LinnDrum.
>
> I am sorry for the misinformation. I would also like to make the
following corrections:
>
> V8 juice really is 1/8 gasoline
> and
> Ted Koppel really is a robot
>
> If your a Simpsons fan you'll get the joke.
>
> Dave :-)
>