J
Jonathan Kirwan
- Jan 1, 1970
- 0
Jonathan Kirwan wrote:
Losing 50% of your power at every connection? Commercial transmitters
would all be on fire.
My thinking, when saying what I said, came from something along these
lines:
http://www.trendcomms.com/multimedi...Copper/Theme/Chapter2/Impedance Matching.html
I apologize if I misrepresented that idea.
15 volt drop at 10 amps is WAY HIGH. Hope the insurance guy doesn't
find out about it after the house burns down. My house wiring is crappy
and it loses less than 1/3 of that.
I measured roughly a 15V drop, running a power saw in a room at the
far end of a home. The run of wire to that end of the home, including
various loops around the walls and via various connectors, appears to
have been around 100 feet each way. The wiring in the walls was 14
gauge aluminum. Not sure what the actual draw was from the saw, but
it was enough to drop about 15V. The reason I bothered with any
measurements at all was because the lights dimmed quite substantially.
Bugged the hell out of me.
I disagree about treating the wires as perfect conductors -- even for a
newbie. That is how the dreaded ground loops get started. It can make a
big difference even on signals as 'trivial' as 1V P-P video into a 75
ohm load. Most newbies treat 'ground' as an afterthought while to me,
it is the most important thing to get right from the beginning. Power
regulation/distribution comes next.
I can't imagine trying to understand a schematic by first replacing
every wire with some complex representation of its impedance and then
trying to fathom it. We will just have to disagree with each other on
this point.
By the way, I took courses on the Tektronix campus back in the 1970's
and this is how they also taught me to examine schematics. It's a
thinking method not of my own concoction.
Jon