6 v to 12 v for car radio memory
My friend has a 1950 Chevrolet pickup truck. He is using a transistor radio powered by a booster module to get 12 volts from the 6 volt battery. To maintain the radio memory there is a wire from the radio that wants to see 12 volts continually. The truck came with the radio and booster and a three wire device that claims to be necessary for the radio memory. As in many restored old cars and trucks, the body and interior work is usually good but you will be surprised at what people do to the electrical system. There is no hook-up data on the three wire mystery component that has a black wire, a red wire and a light green wire. I assume that this is some kind of low current DC to DC converter to supply the memory in the radio. Does anybody have any idea how to hook this up or what is inside?
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Re: 6 v to 12 v for car radio memory
Mystery Component solved!. We were thinking that the 3 wire component was perhaps a miniaturized DC to DC converter to give 12 volts DC to the radio memory from the truck 6 volt battery. Instead, the full power for the booster is connected to the radio and the memory lead on the radio. It seems that when the radio is off, the memory requires very little current, perhaps 8 ma or so and the booster is connnected to the battery at all times and not through the ignition switch. The 3 wire component is just a 6 volt relay so that when the ignition is turned on it switches the 12 volt output of the booster to the radio input power so the radio can function wehn turned on. The memory wire of course is always connected to the booster output so the radio remembers the stations selected and bass and
treble settings. The 3 wire relay uses the difference between the 12 volts from the booster and the 6 volts from the car battery for the coil to pull the contacts to power the radio. Of course it is not really necessary, the booster output can be connected to both the radio power input and the memory wire. However, the manufacturers of this setup indicates that the three wire device, referred to as a type of memory module is neccessary if the radio has a memory capability, sells for $30. My guess is these cost about $5 or so.
Joe
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