New Elecraft Rig: KH1 (Part 3)

Continuing the discussion from New Elecraft Rig: KH1 (Part 2) - #100 by LZ1WF.

Previous discussions:

Does anyone know why the KH-1 has not been designed to work on the 28 MHz band as well?

73 Karel

2 Likes

I’ve heard Wayne saying on some interviews that it’s a compromise. They couldn’t fit more bands in this small design considering all constraints such as having a tuner and keeping the same batteries as in the KX2. Wayne also claims they built the smallest ATU ever to make it fit in the KH1.

2 Likes

Thank you, that makes sense.

The main reason to choose exactly these KH1 bands, in the words of Wayne, N6KR:
As for the KH1, its five bands must be adjacent to each other given the band-pass and low-pass topology we used.

4 Likes

So the bandpass and low pass filters span two or more adjacent bands to minimise parts count (build cost), size and weight. 40 to 15m is a 14MHz span (21-7). Adding 28MHz would make it a 21MHz span, must have been to much of a stretch. And it would have added parts to the ATU as well. Bit of a pity, but they’ve done a remarkable job as it is.

3 Likes

For the early adopters of the Elecraft KH1, as the format of the internal TX log is now known, I updated the KX2 / KH1 log converter to generate a Fast Log Entry (FLE) draft log for this transceiver too.

Comments and suggestions welcome.

https://www.on6zq.be/w/index.php/SOTA.ELECRAFT2FLE

3 Likes

Would it be of some value for a KH1 user to do a “Human Factors” comparison of all of the KH1 functions vs. the same functions on the KX3, in terms of the number of commands (key presses, etc.) to accomplish the same function?

1 Like

Candid questions:

  • What is the objective of the exercise ?
  • How should it be done ?
  • Why “vs KX3” and not vs other rigs used for QRP CW operations ?
2 Likes

Thank you for your questions!

-objective of the exercise: any time that a piece of equipment is used in possibly-adverse conditions, such as, for example, a SOTA activator wearing gloves; holding the rig in one hand; sending CW; logging with the other hand, the equipment must still be designed for relatively easy use. A similar example for public safety portable radios would have the radio to be usable by a firefighter wearing gloves (e.g.: radio having larger knobs) and changing channels or sending a function (e.g.: “man down”). A minimum of user actions, easily-accomplished, is desireable.

-how exercise done: list the user functions of the KH1 (e.g.:CW message send, from memory) and provide a sequence of user-actions to accomplish each function. Repeat for another radio of choice. Compare.

-why “vs. KX3”: just an example, from the the same company (Elecraft). My point here was to see how the same company handled the Human Factors design in scaling to a palm-sized device. Analyzing other rigs would also be interesting, especially going-forward, as other similar, palm-size rigs are released.

2 Likes

You might find this interesting:

1 Like

Thanks for suggesting this reference, Christophe.
The author of the included video admits that it is not “an in-depth” comparison, but was interesting, nonetheless.

My original question becomes even more compelling when we compare the KX2/KX1 for each units’ “number of Controls”. Please see the “Controls” line/row in the referenced document: “KX2/KH1 Features Comparison Chart”:

KX2: 12 switches, 4 knobs
KH1: 4 switches, 2 knobs

With the KH1 having only 1/3 the switches and 1/2 the knobs of the KX2, there must be more “button-pushing/turning” for implementing certain supported KH1 functions. Hence, a more-complex Human Factors design, right?

2 Likes

I own and have used the KX2 and KH1 (and MTR3) extensively. I have also used a KX3 extensively. The basic controls that you typically use during an activation are very easy to use on the KH1 and compare favorably to the KX2/KX3. I have used the KH1 with gloves on, and had no trouble. The user interface is very well designed.

Also… the KH1 has 6 switches, because both the knobs can be pressed in.

3 Likes

Thanks for your commentary, Josh. Spot on, for my original question!

So, am I to understand that there are no KH1 functions that require ANY MORE inputs than their KX2/KX3 counterpart functions?

2 Likes

The basic stuff you would use for an activation are roughly the same. Change freq: rotate VFO knob. Change band: button press to access, up/down buttons to change (on KX2 it’s button press then rotate a knob). Change code speed: button presses (up/down), on KX2 you rotate a knob. Initiate ATU match - button press on both KH1 and KX2. Send keyer memory: two buttons presses (same on KX2). Change power level… irrelevant on KH1 =)

Using RIT requires two button presses on KH1, and only one on KX2.

2 Likes

Josh,
Your last post answers my question, directly. Thanks!

1 Like

Preferences in how a radio functions vary from person to person. I prefer the ergonomics of the KH1 to the KX2. I frequently stand next to the antenna holding the radio in one hand while operating with the other. The KX2 is heavier and turned 90 degrees making it tiring to hold. Weight, bulk, and shape of the KH1 better fits the way I operate SOTA. I home-brewed a folding protective cover for my MTR5. It folds open to support a log just like the KH1 now does. But the KH1 is easier to hold, the paddle better positioned to use, and the KH1 has memory making actual logging pretty much unnecessary. The KH1 log memory feature is much larger than the KX2 enabling several activations in a row. It is important to mention the screen. Unlike other radios I have used, this screen is easy to read in bright sun, shade, with sunglasses, and at night. Compare holding the KX2 with my home made logging tray attached to holding and operating the KH1 in photos below. - Fred KT5X / WS0TA


7 Likes

Fred,
You’ve expanded on the KH1 usability, and the SOTA community will benefit from your observations. TNX de Sevim, WB8BHN

3 Likes

Probably strange question.
Is KH1 already available for purchasing within Europe?