Converter issue

[yaknowthatguy]

Alright gang, I have an idea what I'm looking for, but have had no luck in finding one. I think they exist....but no dice so far.

What I'm looking for is a 24-12v stepdown converter that will run my stereo and ham radio (I wont run the Yaesu at max power), BUT that has either a small battery for memory preservation on the radios, or that I can combine with a small battery and a charging circuit. I've heard of converters that do this, but can't find one. My pinz will sometimes sit for a few weeks, so a converter wired battery direct is a bad idea... plus I'd rather not bypass the master switch. I already have a converter that will handle 30a, so if I can adapt the battery to this it would be ideal.

If someone has a good plan for this, or can suggest a specific product, I'd love to hear about it. I can follow a schematic and make something, I just don't have the skills to write one up for this - and dont know where to find an off the shelf converter that would do this.

Many thanks in advance.

[undysworld]

I seem to remember a post, a LONG time ago, about someone who used a rechargeable 12v for this. You'd have to search the earlier posts. I'd think such a battery could be disconnected via a relay, for periods of long storage. Perhaps whoever posted that previously will respond.

[Jimm391730]

I've heard of people using a 9V battery just to back up the memory. Never done it myself, but I expect you would put the 9V+ to the memory lead and the 9V- to the radio ground.

Memory retention draws very little power (in most radios) so the 9V should last many months... but it is easy enough to try. When you decided to change the 9V you just leave the radio running as you swap batteries, no data lost.