[Elecraft] Re: mobile (long)

[Todd Fonstad]

Dave Pomeroy,  K7DNP, wrote "Can anyone describe their experiences with auto
mobile with the K2/100? I'm wanting to mobile and I'm also wanting to build
another K2. "

I've run mobile with my K2/100 (SN 1130) and the companion KATU/100 for
about a year. This comes after a hiatus from HF mobiling of about 32 years!
(My last rig was the Heathkit SB-101 with the high-voltage transistorized
power supply mounted on the engine side of the fire wall). I have a 1995
Plymouth Voyager with a 4-magnet mount atop the roof with the short-masted
Hustler 3-band resonator adaptor. I usually have the 15, 20, and 40 meter
resonators attached but have also used 17 and 80 meters on occasion.

The K2 works superbly on the road. I've used it extensively on several long
trips from my home here in Wisconsin to such destinations as Wyoming, Texas,
and Virginia. Ninety-nine percent of my contacts are on CW. I find it
extraordinarily easy to use CW while"on the fly" .... too bad the logging
isn't as facile! I've worked quite a bit of DX, even on 40 meters (wow ....
was it easy getting into EU and Asia from the Chesapeake Bay area!). Most of
my long-trip contacts are a diversion to pass the long hours. Running
counties on the County Hunter's net (mostly on 14.565) really gets my
adrenalin working ... better than a cup of coffee to stay sharp! In
addition, I have competed in three state QSO parties as well as other
activities such as the CW MARAC (County Hunters) test from the van. In all,
I've probably logged two thousand mobile contacts in the last year.

The receiver is rock-solid, even on bumpy roads (some of those are called
"Interstates"). Since doing the temperature compensation modification, the
receiver stays right on frequency. The ATU is indispensable and allows wide
excursions within bands when necessary with good results. The noise blanker
is outstanding and has been able to remove all but the last vestiges of
engine noise on 40 meters and everything on the other bands, including 80
meters. I usually keep the  XFIL on the widest setting (1.5 kHz) to catch
callers who are off frequency. In the state QSO parties, I interface the K2
with my laptop's NA program to control frequency and mode as well as to send
exchanges (that's with another driver or, if I'm solo, when I've pulled off
to the side .... LOL!). I've received quite a few compliments on the quality
of the K2 signal, and many ops are surprised to have just made their first
contact with a K2 mobile.

I run #10 stranded wire (insulated!) from the battery (where both lines are
fused) directly to the rig. I have wound some of this line near the battery
around a large type 43 toroid "donut" in an attempt to cut down on
engine-generated QRN. I also employ a toroid near the base of the antenna
mast, winding some of the RG-58U coax around it to attenuate common mode
currents.

There are two minor challenges that I've faced. One is that here in the
"frozen tundra", 45 miles from Lambeau Field, we have cold temperatures much
of the year. It is not uncommon to turn the rig on at the start of a drive
when the temperature is 45F (that's our annual mean temperature!) or lower
to find that the PA cooling fan is running and that the rig won't transmit.
The "PA HOT" warning is also displayed. The quick fix is to reset the CAL
tPA function from where it has mysteriously migrated up to the maximum value
back down to around 20C or so. BTW, I've used the K2 at temperatures inside
the van that have been as low as -11F. There was a slight delay while the
rig awakened from hibernation ... the display was initially weak and the
receiver audio non-existent, but the rig worked normally within a couple of
minutes.

The second is the problem of mounting the K2. The Heathkit SB-101 had an
auxiliary mount (I still have the rig and the mount) that allowed the radio
to slide onto it and couple the RF, audio, power, etc. connections
automatically. Without this arrangement, we are challenged to devise our own
mounting systems. I won't go into a description of how I've worked around
this problem, but I would be happy to send some low resolution images to
anyone wanting to see two or three of these solutions. Beware ... "purists"
need not apply <g>.

Mobiling is just one of the several ways that building and operating my K2s
(one QRP, the other QRO) have serendipitously led me into areas of the hobby
that I had long-since abandoned or had never been able to participate in
with my other rigs.

Considering mobiling with the K2? Go for it!

73
Todd
N9NE
Oshkosh, WI