wrote

Gotcha, but I don't see why anyone would choose to power their receiver
off such a battery. There are plenty of sealed lead-acid and gel cell
batteries on the market that are safe for indoor use and that produce
negligible emissions.

Steve

Hi Steve, I power two transceivers (1 VHF, 1 HF) off a 12vdc deep cycle
battery, and the Drake R8B is powered from the computer's UPS. Other radios
and tuners that can accept external DC get it from non-switching DC power
supplies. Price was somewhat of an issue in a battery that is required for
both normal and stand-by use, and the only reasonably priced deep cycle's
were vented lead-acid types. Once a month I use a powerful charger and only
in an outside vented area. But the 1 amp float charger produces very little
gasses and would not overcharge unless left on for days with no draw on the
battery. For some very high operating temperature receivers such as the
older Icoms, external DC is the only way to go, unless you can provide
constant air movement over the radios. It has zero effect in reducing noise
in my opinion, but heat is the enemy of all electronics and definitely
shortens their lifespan. Unless the receivers have a narrow-band
stabilizing ceramic oven oscillator option, the receiver will drift less
when external DC power is provided.

Jack Painter
Virginia Beach, Virginia