Hi Brad. I've recently been struggling with the same question regarding the
K2. I acquired mine via trade back in September, and then built the KPA100
and KAT100, and began evaluating it as my primary rig. I operate primarily
CW, with some SSB, RTTY, PSK31 on all bands 160 through 10. I use an
Ameritron AL-800H amplifier with up to 1500W output as necessary. I have
very little interest in QRP work at this point, but was attracted to the K2
after hearing so many reports on how well the receiver "hears". After
nearly 4 months of constant use, I've still not made the decision and will
share with you the problems I've run into and things I don't especially
like. If your operating habits don't run parallel to mine, many of these
items won't apply to you at all.
Before getting into the dark side of things, let me say that the K2 receiver
is everything they say it is when it comes to weak signal CW work. I'm
talking about the ability to copy Asian stations on 160 meters in the early
morning hours without the benefit of Beverage antennas. On my old trusty
Icom 765, there are many days when I can hear them in there, but just can't
copy more than a letter or two every now and then. With the K2, the same
stations might be nearly solid copy. The signals don't sound any stronger,
they're just more copyable.
Now for the other stuff. If one is thinking of simply sitting the K2 on the
desk, hooking up all the interconnects, and operating the station as you did
with your old rig, you may be troubled by one or more of these items.
1. ALC: There is no provision on the K2 to interface with the ALC line from
a linear amplifier. ALC benefits are argued like politics, and there are
perfectly valid points on both sides. Here's one you don't often hear: If
you're using an amplifier with a low drive requirement such as I have (pair
of 3CX800s, with grid protection circuitry), ALC feedback from the amp can
be put to good use in limiting the drive. With the K2-100, if you forget to
turn back the power and hit the key, the grid protection circuit is
activated, disabling the amplifier. Since slightly different drive levels
are often required on different bands to drive the amp to full output, this
can be a real pain. Yes, ALC can be useful on CW!
2. Software support: While folks will tell you (as the recent QST review
did) that you can simply define the K2 to logging and control programs as a
Kenwood (570 preferred), many of the programs simply won't correctly
interface with the K2 without unusual operator action. For example, the
logging program DX4WIN will talk to the K2 pretty well as a Kenwood.
However, if you mouse on a DX spot in DX4WIN, sometimes the K2 mode will be
set incorrectly ( mousing on the spot TWICE sets the correct mode). I
understand that this is not seen as a K2 problem, but you won't have that
problem with DX4WIN with a Kenwood rig. I've found similar situations with
other software and the K2. I expect the differences to eventually be worked
out as more and more software includes correct K2 support.
3. Digital modes: The K2 doesn't provide for FSK, but works just fine using
AFSK. However, that means that DX spot frequencies for RTTY will not be
accurate. There is no fixed level audio out from the K2 for input to the
sound card. K2 users have offered a couple of mods to remedy that one.
4. Power Supply Hum: To me, this is a very troublesome issue. Depending
upon the characteristics of your particular DC power supply, you will most
likely need to provide an appreciable separation between the K2 and the
supply. I started with the Astron RS-35M next to the K2, and had problems
with rough CW notes on receive and had to separate the two by more than
three feet before the hum modulation on transmit was gone. I believe the K2
documentation recommends a minimum of 24" separation. I've owned a few
Astron supplies and note that they exhibited various amounts of leakage
flux, so your experiences with this one may vary wildly. Of course, a
switching mode supply circumvents this issue entirely, and if you don't
chase DX on 160 (where the switcher noise may become a problem) it's a
perfectly good solution.
5. The flashing annunciators on the display that inform you that you are in
RIT, XIT and/or Split mode are difficult to see at a glance. A very popular
modification adds an LED to the front panel to indicate those modes and I
can't imagine living without that one.
6. Driving an amplifier: The K2, with its current level of firmware in the
K2 and KPA100, can have real problems when activating the antenna relay in
many amplifiers (and I'm NOT talking about QSK mode). The K2 is very fast
at switching to transmit and bringing up the RF output when you hit the key.
Faster than some amplifier relays, so the K2 momentarily sees a high SWR as
the RF level rises into the open circuit of the still-transferring relay.
The K2 properly senses the high SWR and immediately kills the output power.
This doesn't happen EVERY time of course, and you might not even notice it
happened if you have the headset on. You'll still hear the sidetone. When
it does happen, you have to either turn the K2 off and then on, or run the
power control all the way down and then up to where you had it. A
forthcoming firmware upgrade solves this problem completely, but you may run
into it if you acquire an older K2 without the change. Elecraft was VERY
quick to react to this problem when reported and to provide a solution.
7. Audio: The audio level from the K2 is anemic when compared to many other
rigs you'd use as your primary rig. With the built-in speaker, I found it
adequate, but it needed a bit of external help when driving my 8 ohm station
speaker. This isn't a major issue, but can be puzzling if you don't expect
it.
8. Power rollback with rising SWR: The K2 will begin to rollback the output
power at fairly low SWR levels (mine began around 1.5:1). This can be a
problem when driving an amplifier if it's one that has bandswitch positions
that are shared between two bands (notably, many Ameritron amps). You may
be able to adjust the amp tuned input to achieve a better compromise SWR
between the two bands. Again, a forthcoming firmware upgrade for the KPA100
resolves this by raising the SWR level at which rollback begins to occur.
That completely solves the problem.
9. Loss of power when changing bands: When you change from one band to
another, the K2 will not produce full output for a few dit times when you
first hit the key. So, if you're contesting, change bands, and then send
your call in response to a CQ, you might find the first letter of your call
is incorrectly received because the leading code element is not heard. It
was explained to me that the K2 does not remember its ALC settings from band
to band and recalculates the correct level the first time you hit the key on
a new band. As long as you're aware of it, it's a very minor problem and
can be avoided by just hitting the key once quickly when changing bands.
The K2 will likely retain its place on my desk primarily because of the
excellent support from both Elecraft and other K2 users. Its idiosyncrasies
are much more tolerable if you've ever owned an Italian sports car. Yep - I
think I can hear that K2 calling you, Brad.
73, Floyd - K8AC
----- Original Message -----
From: "Brad Hedges" <***@nc.rr.com>
To: <***@mailman.qth.net>
Sent: Monday, January 19, 2004 9:29 AM
Subject: [Elecraft] Just how good is the K2?
Post by Brad HedgesI have read all the reports. I have seen where various contesters use the
K2. I have even SEEN a K2 <grin>
But I just have a hard time getting over this six pound box the size of,
well, small.
I am in the market for a new primary rig for the shack. I'm getting a pretty
substantial tax refund, and short of an Orion, I can get *almost* any rig I
want. I have pretty much settled on a Yaesu FT-1000 MP Mk V Field, or a used
TenTec Omni VI+ if I can find one, but there is still that voice that says
"K2".
I need some pretty hard convincing. I just built a K1, and while I have yet
to get the transmitter pumping, the rest of the rig is every bit what I was
looking for.
But it's not a "primary station rig" - at least, not for me.
Help?
Thanks,
Brad
K0BHC
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