How could I keep the Radio in my truck from losing it's memory?

Question

Alright, I drive a tractor trailer for a freight company. Of course, there are no radios in the truck. What we(drivers) do is build a box with speakers and a car radio mounted in it. There are bannana plugs on the dash to get power from. Now The only problem is that everytime you shut the truck down the radio will lose it's memmory (presets, Volume level, etc). I could get an analog radio but that is just out of the question. I was thinking more along the lines of a secondary power source. Like connecting a 9V battery connector to the memmory wire so when the truck is off it will still hold it's memmory. Seeing that the radio won't work without this wire being hooked up to the trucks power I would have to incorporate a diode of some sort so I don't fry the battery. What kind of diode should I use and Where should I put it in the circuit? I can't mess with the truck, so whatever I do has to be done in my radio box. Thanks for any info....

Answer 1

I don't see why hooking a 9 volt battery to the memory wire when you remove the radio power supply wouldn't work. They sell connectors to connect a 9 volt battery through the cigarette lighter to supply current to memories while you change the battery in a vehicle so the memories aren't lost in different car functions which include radio memory among others. You might want to wire a switch in the circuit so it isn't on all the time. Check out: http://www.autodax.com/products/toolsequipment/kas295a.htm ...Good Luck...

Answer 2

I don't know if it would work as a 9v battery is pushing the limits of the lower end of a radio's design and may or may not work in retaining memory (espcially as the voltage drops below 9v)

Some people use small batteries from a lawn mower (seen it done in small horsepower pull rope engined boats mainly) or really technical people and more safety worried get the pulls out of emergency lights or medical equipment that are 12 v batteries and are sealed and if enough capacity (such as the small lawn mower) to power the radio also (the sealed ones are expensive but can be found at stores such as batteries plus also)...

just have to wire a wire to charge the battery occasionally. (hooking it up to a small trickle charger will work)

Answer 3

You should have 2 power wires in the back. Red and orange usually. One is hooked to an accesory that turns off with the ignition. Run the other to something like the lighter or something that remains hot while the vehicle is shut off. Or just run the main one to a line that remains hot and turn the radio on and off manually.

Answer 4

i dont think you need a diode
hook up your memory wire/clock wire
to the posative ofthe 9 v battery
and a wire to the ground for the radio
if you plug in the 9 v battery just before you unhook it from the truck you should be ok 10 seconds or less I dont think will hurt a 9 v battery
try it good luck

Answer 5

You don't even need a diode. Just connect a small rechargeable 12V pack inside your box, which is connected to your power connections appropriately. When you disconnect the truck's power from the box, the pack will sustain the voltage to your box. When you connect the truck's power to the box, it will simply charge your pack, plus power your box.
Note, be sure that power is OFF on your box before disconnecting truck power from it, and stays OFF until you reconnect truck power to your box.

Answer 6

Run it off the same jumpers in the dash or overhead that your CB is hooked to. Then tell your company owners to stop being such tight wads and put radios in the trucks. What do they expect you to do? Sing to yourself? It's lonely by your self.

Answer 7

run a jumper wire direct to battery power off the truck good luck