Charles, You can't "convert" a 28 VDC Astron power supply to a lower voltage, unless you replace the power transformer and regulator board, and possibly the pass transistors. Since the Astron linear power supplies use a series-pass regulator design, the pass transistors could burn up if expected to regulate at full design current but at half the rated voltage. That said, you CAN install a 14 VDC regulator board (or modify the 28 VDC regulator board with components suitable for 14 VDC) and run the power supply at less than half its rated load. I would never do this, because the value of a good, high-capacity 28 VDC power supply is always much greater than one that has been hacked to operate at a lower value.
Before you decide what to do, call Fred (the Tech Support guru at Astron) and ask his advice. Go to the Astron web site for the phone number. 73, Eric Lemmon WB6FLY --- In Repeater-Builder@yahoogroups.com <mailto:Repeater-Builder%40yahoogroups.com> , "Charles Lowery" <clow...@...> wrote: > > I purchased a Uniden 28 volt power supply today on ebay. It lookes like the Astron LSRM-25A or 35A both front and back (I assume Astron made it). Without seeing it, I assume it works OK (cost $2.00 + shipping). Has anyone converted one of these to 12 volts? I have no schematics for it and can not find one on the net. If converted what would be the available current? > > Charles, NM4V
