quattro digest, Vol 1 #2998 - Radio Power w/battery disconnect

[Huw Powell]

> Assuming that the cigarette lighter is non-switched, supplying the lighter with a power plug that has a 12 source in it would keep the radio memory. It would actually be interesting to see if the electronic memories (and clock and ECU memory) could be supported by something easier, say 9V or if needed, two 9V in parallel. If so, run to Radio Shack, buy one of those cigy lighter sockets and a couple of 9V battery snaps and a couple of 9V batteries, wire the ground (cigy lighter shell half) of the 9V to negative of the 9V's, the center to the + side, voila!, non-volatile radio memory when you need to pull the battery. Total cost, about $5. Of course, the question is, will 9V hold the memory?
>
> Note, be careful if this is the set-up. Until the battery is disconnected, it will TRY to re-charge the 9V batteries at 12V. This may cause a problem for 9V batteries that can't be recharged. Too bad there aren't any small 12 batteries that have a little real current (photo batteries just don't have enough).

Probably easier and cheaper to just buy one.  The "product" should have
a diode in it to prevent the attempted 12v charge of the 9v battery.

I picked one up, but all I have to worry about are radio station
presets, so half the time I forget to use it anyway, and the other half
I can't remember if it worked!

--
Huw Powell

http://www.humanspeakers.com/audi/

http://www.humanthoughts.org/