[G.Michael]

$65
This is a nicely made unit. 
Two inputs: Battery and Battery Charger
Output: Battery Voltage
In it's simplest operation, connect the cables and put the left switch in the OPERATE position.  When you're finished, put the switch in the CHARGE position.  (I didn't pay much attention to the FLOAT switch, because I used a CTEK charger, and in my experience CTEK chargers are pretty smart about no overcharging batteries.)

Includes all three cables.  You can see the types of connectors in the photos. 
Connections on the switch box, from left to right in the third photo:  12VDC output, battery charger input, and (hardwired) battery input.

Battery and charger are not included. 

[jjss49]

this is cool... so you actually just use a car battery on the other end of this, and then use the dc output plug into computer streamer, dac, tt motor, what have you, is that correct?  is there a regulator in this that doesn't allow the car battery to surge current and damage the equipment downstream?  or does the 4a fuse basically handle that?  in your use, has the fuse blown and need replacement at all?

thx

[G.Michael]

I assume that it's a battery and some switching... except that I don't know know how the "Float' works to reduce the charging voltage going to the battery.  I got this from a friend of mine who said he had it custom made (which I think means he overpaid for it), and then never used it much. 

I never examined the internals of this--in part because years ago I built one of these myself and never used any regulation, and the only surge protection I used was a fuse.  Big batteries have good regulation, anyway.  I also put a voltage doubler in the one I built, and used the 24VDC output to power a small ClassD amp.  I never had any problems with it.  And I just figured that this one that I'm selling is similar, except for the "Float" bell and whistle. 

I'd say that if you want to get into battery supplies, it's nice to have a  switch box like this one. 

[G.Michael]

Price reduced.

[G.Michael]

Bump... and substantial price reduction.