[Elecraft] KX3-2M extended receive?

[Mike Morrow]

Steve wrote:

> My basis for my comments is backpacking. I ask those that are consider the
> multi-mode operability of the KX3 as being the sole reason wideband receive
> is not feasible and that an HT must be required to supplement that which the
> KX3 does not cover if you have ever gone backpacking. That doesn't mean a
> short day hike or walking a mile to a camp site for the weekend, I am
> talking about packing everything you need for 2 or more days covering 20+
> miles.

Portable operation out in the boonies has been more than 95 percent of my HF
ham operation since completing military service 33 years ago.  (I wasn't able
to do much hamming in the service, even though I held a license long before.)

My backpacking lineup since 2000 has been the K1 for HF, and some small HT
for VHF/UHF coverage.  I've used the VX-3R since 2007.  The HT is set to cover
FRS, local law enforcement in the area, game warden frequencies, local park
and/or forest service frequencies, aircraft unicom, plus the odd ham repeater
and simplex frequency.  I research and make use of all available frequency
data for the region I'm in.  It can be useful.  Power for the K1 is a 4.5 A h
SLA battery, plus a reserve 10-AA cell pack.  I also always carry a small AM-FM
radio.

> Have you experienced that and the different challenges associated with
> packing for treks like that? Have you felt the affects on your body after
> a trip like that?

Er...yes...many time in the last third of a century.  If you want a real workout,
come to the Sipsey Wilderness in north Alabama since several EF4 and 5 tornadoes
tore through it on 27 April 2011!

> ...every pound you add is that much more weight you have to carry with you
> the whole time.

True, and that's why what you say later indicates that you are making life hard on
yourself, without cause, when you state:

> ...on past trips I have taken my FT-857D on 3 day backpacking trips covering
> in the 18-24 mile range through the Appalachian mountains. The set up I have
> for the FT-857D complete is right around 15 lbs.  That's a LOT of weight.

You're absolutely correct.  That's an *insane* amount of weight for even an
overnight trip.  Your equipment choice would be among the very last I would
choose.  Let's look at some choices, popular or otherwise:

Radio          Weight (lbs)  Volume (in^3)   Receiver Current (amps)   
FT-857D            4.7           113                 0.8
FT-817ND           2.6            52                 0.35
K1                 1.5            64                 0.08
KX1                0.7            19                 0.04
KX3 (prelim)       1.5            43                 0.15
 
IMHO, the FT-817 and FT-857 are totally inappropriate for serious backpacking
due to unit weight, the outrageous current consumption just on receive, and
most significantly, the size of the power source (unless you've got a couple
of furry helpers such as WG0AT has.)

BTW, the VHF coverage of the 817ND does not reach the NOAA channels, and
the VHF coverage of the 857D does not cover the frequencies most often used
in the national parks, forests, rivers, etc.

> Therefore by packing lighter and smaller the enjoyment of your adventure
> goes up and the effort, wear, and tear on ones body goes down.

One might reasonably suggest, based on the particulars in the above table,
that selecting a rig appropriate for backpacking might be helpful.

> The FT-857D covers everything I need in one box - its a single rig solution
> and that out weighs the added weight.

The 857D is **monstrously** heavy for backpacking!  Almost five pounds!  And
stunningly energy inefficient.  It's a mobile rig.  Then there's the battery.
I can't imagine carrying such a thing plus its battery on any sort of portable
trip.  I really really can not.  I haven't done anything close to that since
I carried the AN/PRC-25 FM backpack radio in service.

> That will give you an idea of what its like.

Thanks.

> Adding extra gear to a backpack is probably the number one rule to avoid.

Number one rule is "select the appropriate equipment"!

> Adding an HT at a couple lbs is bad enough by itself,

Do you know how large a wide-range HT like the VX-3R is?  With spare battery
pack it's five ounces, and less than 6 cubic inches in volume.  You're worried
about that???  Leave out one granola bar. :-)

> I personally couldn't care less about the public service and MARS frequencies
> above 2m, its the NOAA weather channels...

But there are hams who have legitimate need of operating (transmitting) outside
the ham bands as part of a service function.  To cover completely all US service
MARS VHF-FM frequencies, the KX3 two-meter module would need to function between
142 and 150 MHz.  That's an expanded capability (if any is to be realized) with
far more potential public service value than providing NOAA weather channel
coverage.

> ...the rig will fill a unique niche...a CW AND SSB rig on HF in a compact,
> light, and well thought-out package.

Well, it'll be one-third the weight and volume, plus one-quarter the receive
power consumption of what you're using now.  You'll fell positively unloaded,
even if you carry an HT and five battery packs. :-)

You never described the size, weight, and maximum service time of your battery.

I actually broke both bones in my lower left leg on a solitary wilderness hike
in 1998...but that's another story altogether, and it didn't involve any radio
(not even cell phone) technology.

73,
Mike / KK5F