Well.. a million thanks for that. Quite a cool history lesson as well. So
now I'm looking for an SEA tuner... LOL...

Listen, that all makes perfect sense but just to clarify, a.) now I know why
that triton did so poorly when tested. We calc'd 1/2 wavelength for the
longwire, and b.) Again, for continuity and clarity of this thread for
future surfers...... what then, considering our discussed auto-tuners, would
be the optimal length for a longwire that would be used for amateur/MARS,
3-30MHz?
Pick 1/2wavelength on say 2.8Mhz and just cut it? Or calc 1/2wavelength on
the lowest and add 5% or some arbitrary odd number??
Which plan will offer the least chance of dropping a 1/2wl further up the
band on a desired frequency?
thanks,
Woody


"Bruce in Alaska" wrote in message
...
In article imYki.1884$YH3.394@trnddc08, "Woody"
wrote:

Yeah, I noticed the same thing with the motorola triton, another
antique....
maybe the newer ones aren't so quirky?
W

Interesting you should notice that. The original Binary Switch Lump
Constant Autotuners were those designed for the Triton Series MF/HF
SSB Radio's, from Motorola, by Bill Schilb. When he left Motorola
and came west, to Northern Radio in Seattle, he brought that technology
with him and introduced it to the MF/HF Marine Market. First at Northern,
which never did anything with it, and then on to SEA, thru the
ex-Northern Engineering Team, that followed Dick Stephens, from
Northern, to SEA, as Northern was sinking into oblivian. The first
Marine Product with this technology, was the SEA-1601 Autotuner, Designed
by Bill Forgey, and Mark Johnson. A sucsession of improvments followed
culminating in the SEA-1612B Autotuner. This is the model that SGC
copied, for their original product, including the Firmware that still had
the SEA Copyright, compiled in the code. Most of the later Binary
Switched Autotuners are, either Copied, or Reverse Engineered,
adaptations of the SEA1612B System. All these tuners NEED a Low
Impedance RF Ground to work against, as well as a Longwire who's length
is SPECIFICALLY set up to put the 1/2 Wavelength Point in a non used
portion of the Spectrum. They will NOT tune within 2% of the Natural
1/2 Wavelenth point of the Longwire connected, where Antenna Impedances
near Infinity.

There has been considerable work done, over the years, on making this
type tuner, drive Balanced Antennas. Some have used a 4:1 Balun,
directly across the tuner Output, with limited sucess. Some have
decoupled the Tuner from it's Coaxial Feedline, Power, and Tuner
Indicator Lines, by running them thru a Bifilar Wound Torroid at
the Tuner end, and then putting the tuner in the Center of a Dipole
cut for the Lowest Desired Frequency of the System. This type has proved
a better system than the Balun, but I have used both at Limited Coast
Stations thruout Alaska, and most are still in operation today.
G & L Marine Radio in Seattle, once designed an SEA-1612B based Autotuner
that had two Tuner boards, one for each side of the Balanced Antenna,
that ran off a single MCPU and Detector System, and just latched
the same Data into both boards. I never actually heard how well Don Sr.
got it to work, but always thought that it was an interesting concept.

Bruce in alaska
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add a 2 before @