[Elecraft] [KX3] "HF Pack Lite": Remote control of KX2 via UP/DN buttons on the MH3 mic

[Wayne Burdick]

Gets me out of the house, that’s for sure. I’ll be happy to send you the new code.

Wayne
N6KR


> On Sep 11, 2017, at 12:47 PM, Howard Hoyt hhoyt at mebtel.net [KX3] <KX3-noreply at yahoogroups.com> wrote:
> 
> 
> Wayne,
> 
> That is just plain cool, kudos!
> 
> Howie - WA4PSC
> 
> 
> 
> On 9/11/2017 2:27 PM, Wayne Burdick n6kr at elecraft.com [KX3] wrote:
>>  
>> Use of an HF radio while walking, or at least while standing (perhaps taking in a view of the great outdoors), is generally referred to as “pedestrian mobile.” Some operators even add /PM to identify as such.
>> 
>> Two common forms of pedestrian mobile operation include:
>> 
>> 1. HF Pack: This usually implies a radio carried in such a way that the front panel can be used and the display viewed at all times. Often a substantial antenna is used, as well as a large battery. This style of operation may require a specialized backpack and other hardware, and is reminiscent of military field communications.
>> 
>> 2. HT-Style: This is as simple as it gets. Attach a whip antenna to your hand-held radio (e.g., KX2 or KX3), connect a trailing ground wire, and off you go.
>> 
>> I’m interested in a third form that’s somewhere in between the two:
>> 
>> 3. HF Pack Lite
>> 
>> This is similar to HF Pack, in that the radio is worn in some fashion, but it’s optimized for light weight and simplicity. For example, it might involve:
>> 
>> - placing the radio inside a small day pack, sling, or waist pack
>> - using the radio’s own internal battery
>> - a very lightweight antenna, such as a telescoping or flexible whip
>> - simplified user interface, with just essential controls
>> 
>> Combining all of the above, you get a minimalist station that allows for a lot more freedom of movement and won’t wear you out because it’s so lightweight. HF Pack Lite is also ideal for those (like me) who wish to remain under the radar during urban hiking.
>> 
>> I recently made progress on my own HF Pack Lite station that others may benefit from.
>> 
>> First, I found a great way to carry the KX2 or KX3: I’m now using a Patagonia Atom 8L Sling, purchased at REI. This bag is very small, has an internal compartment for the radio, and has a zipper that allows the antenna to emerge at the top. Being a sling, it has roughly the aesthetics of a “quiver,” with a single strap you place over your neck and shoulder, like a camera bag. The only modification I made was to add a grommet at the bottom through which I pass the mic cable, earbud cable, and ground wire. I’m considering making a little harness for these to speed up connect/disconnect.
>> 
>> Next, I’m working on a firmware release that will allow extended radio control via the MH3’s UP/DN buttons. Initially this will be added to the KX2, then to the KX3 after field testing.
>> 
>> Here’s how it works:
>> 
>> Each time you press the mic’s UP and DN buttons together, you advance through a set of mic-based operating functions. At present, these include:
>> 
>> VFO control (default; this is what the UP/DN buttons already do)
>> Key (hand key or keyer paddle using UP/DN buttons)
>> Filter bandwidth (a few per-mode discrete selections)
>> AF gain
>> ATU tune
>> Band
>> Mode
>> 
>> Morse code audio feedback is used to report the selected function. If you go through the selections rapidly, the Morse characters are truncated, so with a little practice you can quickly navigate to the function you want. Functions are arranged from most often to least often used.
>> 
>> Other subtleties:
>> 
>> * Anytime PTT is pressed, the menu resets to VFO control (a safe default).
>> 
>> * Whenever the mic menu is used, all regular front-panel controls are locked out, preventing their accidental adjustment. (Thanks to Matt, W6NIA, for this suggestion.) All controls are unlocked if you power down and back up.
>> 
>> * A long hold of the UP/DN buttons puts the KX2 into a “standby” mode, at about half of its normal current drain. Another press of the UP/DN buttons restores normal operation.
>> 
>> I started testing this yesterday. The small sling pack is a joy to use compared to bulkier backpacks. It stays in place surprisingly well, and with just a KX2 (1 lb with internal battery), it’s easy to forget you’re wearing it. The mic controls are very intuitive in both CW and SSB modes. 
>> 
>> One thing I have yet to find is a 4 to 5 foot ultra-flexible whip to replace the MFJ-1820. Ideally it would cover multiple bands. The MFJ whip is light enough, but it doesn’t coexist well with trees and doorways, and it’s still a bit too obvious for my taste. (See “under the radar,” above.)
>> 
>> In short, HF Pack Lite is a great way to indulge in a bit of radio while burning some calories, birdwatching, sightseeing, or engaging in post-apocalyptic Neighborhood Watch.
>> 
>> Comments or suggestions welcome. 
>> 
>> 73,
>> Wayne
>> N6KR