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I'm a relatively new ham (licensed a couple of years ago, occasional activity on 70cm and 2m, mostly repeaters). I'm looking to extend my ham experience and am interested in digital and packet modes.

I'm interested in APRS. The main reason is to update my location when I'm off to wilderness, which is often. But outside of Europe and North America, I see that there are not many APRS digipeaters around. Let's say I want hike for days in Central Asia or the Himalayas. What options do I have? Is there some portable HF rig I can carry? When I'm in some deep narrow valleys, is there any hope of updating my location?

Any experience or suggestions will be helpful.

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  • $\begingroup$ In areas as remote as that, you'd be better off subscribing to one of the commercial satellite-based services. Otherwise, you'll have to provide your own infrastructure by dropping repeaters along your trail like breadcrumbs. $\endgroup$ – Dave Tweed N3AOA Sep 5 '16 at 12:52
  • $\begingroup$ I guessed so. But my question is more like- let's say I start my trip from a big nearby city (let's say a few hundred km away). I may be able to arrange a digipeater (what is a good digipeater for such case anyway?) in some place there. Would I be able to send packets there from the hills, or narrow valleys? What kind of setup would I require? Probably HF, but I'm not sure and what kind of rig would I need? Or do you think this can't work at all? $\endgroup$ – hamster Sep 5 '16 at 12:55
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So you want to broadcast your location using backpack-portable equipment from deep in a narrow valley hundreds of miles from civilization. I'll assume that you would also like the ability to get a message out when necessary. These are very demanding requirements. I don't think that there is any inexpensive, 100% reliable way to do what you seem to want, but here are some alternatives to consider.

Option: Morse code QRP (low-power) transceiver

Pros:

  • Radio, battery, and antenna can be under 1.5 lb / 0.75 kg
  • Radio can be inexpensive if you're willing to homebrew it
  • Simple equipment, therefore hopefully reliable
  • Can hold a conversation, rather than just delivering a simple message
  • Can normally communicate out to about 1000 miles / 1600 km with ease
  • No computer required
  • Very power-efficient

Cons:

  • Results depend on propagation to some extent
  • Morse code knowledge and QRP skill required

Option: satellite phone

Pros:

  • Theoretically works from anywhere

Cons:

  • Expensive
  • Fragile equipment
  • Battery hog

Option: PSK31 over HF

Pros:

  • No Morse code experience required
  • Easy propagation to about 1000 miles / 1600 km

Cons:

  • Results depend on propagation to some extent
  • Amateur radio skill required
  • Some sort of computer required; computer is fragile and battery-hungry

Option: APRS via ISS

I'm talking about APRS using the International Space Station's digipeater (or another satellite's). (more information).

Pros:

  • Potentially send APRS messages from anywhere!

Cons:

  • Skill required
  • Need a fragile gain antenna
  • Need some sort of computer for satellite pass information and packet generation
  • Difficult for one person to aim the antenna at the satellite and operate the radio at the same time
  • Need to get a short packet out during a very brief satellite pass
  • Depends on a single digipeater in orbit, which may be hopelessly congested

Option: Personal Locator Beacon (PLB)

PLBs are similar to EPIRBs used at sea: a simple, rugged commercially-made transmitter that is designed to transmit an urgent MAYDAY message. When a PLB is activated, generally a Search And Rescue (SAR) team is called out.

Pros:

  • Reliable and rugged
  • Simple to use
  • No subscription required

Cons:

  • Can't use it for routine updates
  • If a SAR team responds, the user may be liable for the cost of the rescue attempt

Option: Satellite Messenger device

A Satellite Messenger is a simple commercially-made device that allows the user to send text messages via the Iridium or Globalstar satellite network.

Pros:

  • Reliable and rugged
  • Simple to use
  • Can send regular non-emergency updates

Cons:

  • Subscription is required
  • The "jury is still out" on how well they work, according to the REI article

Other options

  • WSPR: I wouldn't choose this option, because there is no good way to send a MAYDAY / SOS
  • Winlink: I wouldn't choose this one either, because it requires a strong signal, which would require a big battery and larger antenna

Personally, I would choose the QRP Morse code transceiver (with a PLB or a Satellite Messenger as a backup), but I already have experience with Morse code QRP. This is a skill, which takes some time to learn, that would need to be acquired and practiced in civilization before you head out to the middle of nowhere. But it's the method that uses the simplest equipment and the least power. By the way, for any of these methods to work reliably you would need to hike out of the narrow, deep valley.

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  • $\begingroup$ Very interesting. Thanks. If there's no need to send out a message but just the location, I find WSPR attractive. This is also close to what I was looking for. But your description of CW has piqued my interest. You said it doesn't need heavy equipment. Could you give some suggestion on what sort of transceiver, antenna and keyer one should start with? What do you use for QRP? $\endgroup$ – hamster Sep 6 '16 at 19:51
  • $\begingroup$ If you wanted to use a commercially-made radio, then a Yaesu FT-817 or an Elecraft KX1 or KX2 would be a good choice. (I'd prefer the KX1 for being the lightest and most battery-efficient, but the KX2 or FT-817 allow more bands and modes.) There are also QRP kits galore. Those radios all include keyers. For an antenna, I would probably use a wire 10m - 15m long, with a counterpoise wire or two, and an external QRP antenna tuner. Or maybe a doublet made out of two pieces of wire with a popsicle-stick spacer in the middle, if there were lots of trees. So many options... $\endgroup$ – rclocher3 Sep 6 '16 at 20:19
  • $\begingroup$ The KX1 and KX2 look great. I think it's a hassle fixing up antennae when you're outdoors or in trouble. You do them when you are in leisure. So a quick way to update location for your family/friends would still need a portable but easily usable antenna. I'd have to try all these things before I can make more comments, but do you know if the antennae described here (g4ilo.com/wonder-wand.html) would work with CW and transceivers like KX1 and KX2? $\endgroup$ – hamster Sep 6 '16 at 20:33
  • $\begingroup$ The antennas I'm talking about are wires thrown over tree branches that take typically 10 minutes to set up, depending on how useful the trees are. Without trees, you need some sort of self-supporting vertical. A vertical that uses a 1.25 m whip won't be very efficient at all. The more efficient the vertical, the heavier it is. Buddipole make a good vertical, but I don't know that I'd want to take it backpacking. $\endgroup$ – rclocher3 Sep 6 '16 at 20:39
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    $\begingroup$ You sound like you're pushing the limits of what's possible pretty hard... In wilderness, in central Asia, I'd want some capable traveling companions and a couple redundant communications methods. I wouldn't go solo with just one radio: that's good enough for being 50 miles into the wilderness, not 500. But maybe that's just me. $\endgroup$ – rclocher3 Sep 6 '16 at 20:58
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Apart from matured and highly reliable commercial satellite-based services, WSPR can be another 'DIY/experimental' alternative for broadcasting your location from wilderness. See examples for balloon, photo and ocean floater, photo.

WSPR is an very low speed mode with 2x to 3x dB SNR advantage over many other digi-modes. Range of a few hundreds to a few thousands km are possible with a few watts, or less, of HF transmission power.

A global network of receiving stations are already setup.

EDIT: If broadcasting position and/or maintaining telecommunication are essential for 'safety' reasons, mature commercial satellite equipment should be used. As said, WSPR is 'DIY/experimental'.

Some satellite system uses a large number of LEO (Low Earth Orbit) satellites (Iridium etc.) and would have better coverage probability for partially sky view obstructed locations. Satellites can appear at higher elevation (near Zenith), multiple and time-varying sky positions. If you wait a while, one of the many satellites may move to a position in sky with direct line-of-sight toward you.

Depending on where you are on Earth, those use equator geo-sync satellites (Inmarsat etc.) demand "much more openness" sky view as satellite may appear at fixed and lower elevation (toward South and toward horizon) positions.

Even LEO satellite may have better coverage, no satellite works at too deep and too narrow valleys.

Examples of mature commercial equipment for 'safety' (non DIY/Hobby) uses 1 2 3

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  • $\begingroup$ This seems very interesting. The activity map on the WSPR website however is full of reports from Europe, North America and Australia. Maybe I could try it from "real" wilderness- do you know of some good getting started guide to this protocol, esp things like what sort of rig I need, and how can I quickly test it with my existing equipments? $\endgroup$ – hamster Sep 5 '16 at 21:11
  • $\begingroup$ You may contact equipment seller and also end-users for experience and how-to setup. Equipment shop.qrp-labs.com shop.qrp-labs.com/index.php?route=information/contact. Suggest asking the seller to see if a customized software is needed and an external power amplifier for a few watts. The floater operator is a highly experienced ham, email zl1rs@yahoo.com $\endgroup$ – EEd Sep 6 '16 at 5:05
  • $\begingroup$ I found some useful information on G4ILO's website. Here's the page on WSPR: g4ilo.com/wspr.html (WSPR - Distant Whispers). His website has other info on the antenna and transceivers for QRP operations like this, which is also useful in the wilderness. Here is another page with similar details: amateurradio.com/a-wspr-handy-walkie (A WSPR Handy-Walkie) $\endgroup$ – hamster Sep 6 '16 at 9:39
  • $\begingroup$ Another low-power (need external a-few-watts HF power amplifier in your case) solder kit with full Arduino open source appnotes.etherkit.com/2016/04/10-milliwatt-si5351a-wspr-beacon github.com/etherkit/Si5351Arduino github.com/etherkit/JTEncode gist.github.com/NT7S/2b5555aa28622c1b3fcbc4d7c74ad926 30meters band generally good for day and night fair operation. $\endgroup$ – EEd Sep 6 '16 at 10:06
  • $\begingroup$ Thanks. What is a good handheld (or very portable) HF (or all band) transceiver? I have read about some Yaesu models (857, 817, 897, 450), with different power ranges- is there a good resource/webpage about this as well? $\endgroup$ – hamster Sep 6 '16 at 11:29

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