Archive of the former Yahoo!Groups mailing list: Vintage Simmons Drums (UK) Users Group

OK, me again, with insomnia, hence the somewhat slow brain...

I checked the schematics and noted that the two components on the + side
of the battery is in fact "just" the mentioned resistor (37) and the
diode (30) already in place.

http://www.electronic-obsession.se/studio/simmons/mtm_battery_circuit.jpg

So I cannot see any need for another diode. Please correct me if I'm
misinterpreting anything.

/j.


jesper skrev 2011-12-29 05:00:

> Hi WT,
>
> so, basically just between the PCB solder point and the red wire in my
> photo? To block any voltage from reaching the battery? Any critical
> value or would any decent diode do?
>
> thanks,
> /j.
>
>
> WT skrev 2011-12-29 00:50:
>> I would just put a diode in series with the + side of the Lithium-cell.
>>
>> How you do it depends on where you put the Lithium-cell.
>>
>> WT
>>
>> ----- Original Message -----
>> From: "jesper"<jesper@...
>> <mailto:jesper%40electronic-obsession.se>>
>> To:<Simmons_Drums@yahoogroups.com<mailto:Simmons_Drums%40yahoogroups.com>>
>> Sent: Wednesday, December 28, 2011 10:57 AM
>> Subject: [Simmons Drums] MTM and change of battery
>>
>> > Hi list,
>> >
>> > I thought I should change the battery of my latest MTM today. But since
>> > I was stupid enough not to make notes or take pictures when last time
>> > doing this I dug out one of the other units to have a look.
>> >
>> > No. 114 had it's battery changed by the former owner and as far as I
>> > remember I copied the work in my other MTM. Apart from the removal of
>> > the old battery and the insertion of a AA-sized Lithium dito I can only
>> > see one change: the lifting/removal of resistor 37. I did the same on my
>> > other MTM and both works well, both functions and memory.
>> >
>> > Here's a shot of what can be seen inside no. 114.
>> > http://www.electronic-obsession.se/studio/simmons/mtm_battery_mod.jpg
>> >
>> > So techs, let me know if this is wrong. Should I lift diode 30 too?
>> > Anything else? The schematics aren't the best and I'm no master at
>> > reading it anyway. :)
>> >
>> > Happy holidays,
>> > --
>> > electronically yours, jesper
>> >
>> > - -- --- ---- ----- ---- --- -- -
>> > www.electronic-obsession.se
>> >
>> >
>> > ------------------------------------
>> >
>> > Yahoo! Groups Links
>> >
>> >
>> >
>>
>>
>
>

--
electronically yours, jesper

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