how do i build a isolator to charge a small 12 volt battery powering an xm radio. with xm plugged into car battery severe ground loop. xm ru nning seperate battery no noise. how do i isolate small gel cell from big battery noise, and still charge it. what would a diode circuit look like?
Thanks
2006-09-03 06:03:02 · 5 answers · asked by gary p 2 in Cars & Transportation ➔ Car Audio
To build one, you need some REALLY high powered diodes (75-100 amp range). The didoes would be connected back to back (anodes together) with the connection point being ran from the charging system. The other ends (cathode) of the diodes would be connected to each battery's hot side. The diode networks MUST be in a box that also serves as a heat sink, as the diodes will get very hot. All grounds should be made to the same location.
Alternator system┐
battery────|<───┴──>|──battery
cathode──|<──anode
2006-09-06 13:11:06 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Get one at Radio Shack or any RV or marine supply outlet (ships store) or any auto sound shop.
BTW, batteries do NOT make "noise". Charging systems do sometimes. A battery isolator is not going to help you with that since the battery will be in the circuit when the engine is running. You need a filter to get rid of the noise, not a battery isolator.
A battery isolator isolates the battery and the accessories that it feeds when the engine is off. This is only to prevent the powered accessories from draining the main battery. An XM radio by itself draws so little current that you'd have to run it for days to drain the main battery.
2006-09-03 13:13:47 · answer #2 · answered by Bostonian In MO 7 · 0⤊ 0⤋
that doesn't sound like a ground loop, more of rectify, alternator noise, maybe a power filter would be lots better, ask at a CB or Ham Radio store for inline power filters.
2006-09-03 13:09:00 · answer #3 · answered by Master U 5 · 1⤊ 0⤋
Just go buy one from Radio Shack.
2006-09-03 13:05:29 · answer #4 · answered by troythom 4 · 0⤊ 0⤋
yeah the first one
2006-09-03 13:10:28 · answer #5 · answered by m_c_b_1979 2 · 0⤊ 0⤋