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eHam Forums => Misc => Topic started by: WB8ISG on February 03, 2008, 06:52:28 AM



Title: 12v battery constant voltage maintainer
Post by: WB8ISG on February 03, 2008, 06:52:28 AM
Does anyone remember the article in QST describing a device that is used when operating off a 12V supply that keeps the voltage constant?  The circuitry keeps the voltage constant even as the battery discharges (to a pont!).  A ham had built this and began to sell them commercially--around $125 I think, and it was discussed in QST in just the last year or two.  I have gone crazy trying to find it!  Any help here would be much appreciated...Thanks!


Title: 12v battery constant voltage maintainer
Post by: NA0AA on February 03, 2008, 11:52:21 AM
W4RRY has the original battery booster, but MFJ now sells one as does another individual ham.

Yes, they work as you describe - it's a mini switching power supply that boosts the battery voltage to 13.6 or so by drawing more amps and converting 'em to volts.  But they do let you wring every last watt out of your lead by keeping your radio working down to the 10.5 volt dead-zone.


Title: 12v battery constant voltage maintainer
Post by: WB8ISG on February 03, 2008, 03:32:14 PM
Thanks so much for your help!
Bryan


Title: 12v battery constant voltage maintainer
Post by: W3RPM on February 23, 2008, 04:21:18 PM
Is a diagram available for those that want to build it or possibly scale it up to supply more current?