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Lynn Coffelt
 
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Default what size wire to use for 30amp 12v circuit ?



So, now your saying your theory only applies to certain radios? Then

you
shouldn't make blanket statements like you did. You mislead the average

joe
who reads this newsgroup. It is not common knowledge and while it may

be a
"fact" for "one" radio, it is certainly not a "fact" in general. I

disproved
your statement on the Icom 735, and today I disproved it on the SEA222,
Icom-710, Icom-802, SEA235 and a Yaesu FT-897. I'm not disputing the

fact
that minimizing voltage drops on an HF installation is of prime

importance.
I just think you are way out of line making such a statement and

claiming it
as a commonly understood fact.

Eric


Eric, just how did you disprove this? Using the same setup that you
used in your original experiment? Well, now, why don't you try modifing
your setup and put 30Ft of #14 Wire from your very stiff powersupply to
the radios.
Now try the putput power test again, and come back and tell us all
what you find.

You see Bill Forgey, the Retired Chief Engineer at SEA, and I, did all
of these experiments years ago in the SEA Engineering LAB, and concluded
that yes, this was the case. One of the reasons that more headroom in
the HF Amplifier sections was a prime design factor in the SEA 322-330
Series Radios, but which still did not completely resolve the problem of
trying to operate a 20+ amp Current draw, thru a less than steller
Power Wire.


Bruce


Car audio caps can always beef up the supply transients needed for solid
state SSB and stereos.

greg


You bet! the big capacitors (condensers, really) were often used here to
help SSB rigs "whistle" or "five, five, five" up near ratings. In fact the
internal big filter capacitors in bench test power supplies contributed
trouble pinpointing the problems bringing rigs up to snuff. When the DC
power wire resistance caused momentary voltage drops in a real world
installation, the Simpson 260 couldn't see what the voltage actually was
during PEP peaks. Just a little needle quiver. (forget the digital VOM....
it read all over the place) When you finally sweated and groaned the old
Tektronics scope (me..... Heathkit) up on the ship/boat, the cause of
channel changing, low power and tuner lock-up became clear. Once in a while
a quick BIG cap across the SSB power terminals just before we took Bob Z
aboard would do the trick.

I enjoyed your Peeair story, Bruce, I know Don must be rolling over in the
grave. (I did like Don's little active (Dymek?) antenna, though, to get the
WEFAX antenna up and away from the digital noise disaster in the pilot
house)

Old Chief Lynn