Loops can be very efficient, but small loops sold by most antenna companies are just too short. Best for 20/30/40m would be a 19ft perimeter loop.

Gil.

??  21 x 3.14159=.....wow, that's a lot of copper! 

Oops, I meant perimeter, not diameter!

Good looking loop Jon. Now you can get fairly cheap vacuum capacitors from Russia, not much more than a good air capacitor.

Gil.

Certainly, but 1A on receive is still an enormous current draw when you're operating on batteries. If you're operating close to your car or have some means of transportation, that's great. We are talking mainly about prepping here though, and in such an application, that radio is not a good choice IMHO. To power it, you need a larger battery and a  larger solar panel. Even the new battery chemistries aren't that small if you want a reasonable operating time. If you need to hike out of a situation on foot with a backpack, your 891 and its associated equipment will end up in a ditch after a few miles... For a camp radio, maybe, with a solution like OH8STN uses. He is the only one I have seen who came up with a workable solution, but still, I would not want that extra gear size and weight.

Gil.

The FT-891 is a great alternative as you can just leave it at 5 w and if you need more just dial it in. You dont need 100w or the 25A draw when you can make contacts at 20watts with a good antenna like a linked dipole

Certainly... But the 891 burns 5A at 5W output. My MTR burns 0.7A at the same power output... Not to mention the 35mA on receive...
Gil

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Gil.

Definitely, as they are, those modes are of little use for our purpose. The technology used though could be modified to allow chat, drop messaging and SOS emergency beacons, maybe. There are modes that do some of that... I still need to further investigate FSQ, but none were really engineered for survival radio.

The complexity problem remains... There just aren't enough tablet applications for radio. A laptop in my book is too much trouble and an extra failure node. It would be interesting if a Chinese manufacturer would combine an Android tablet and a 5W HF transceiver. The programmers would get to work then.

All that said of course, being able to reliably communicate with a simple $50 CW  radio is hard to beat, even with the new high performance modes. I'll investigate anything interesting, but if the SHTF, I know what I'll grab first...

BTW, the only other electronic device I might want aside from a radio is a solar pocket calculator...

Gil.

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Excellent points Ray. I think the future of portable digital will be tablets, then integrated systems... If only someone made a tablet with a built-in HF transceiver! I wish there were more programmers developing digital software for Android. You can get PSK, but not much else...

No doubt the new digital modes are very efficient. I just saw a guy on FB post an image of a series of WSPR spots with one milliwatt! With a few thousand-mile spots!

But of course, Morse is simpler and gets the job done in most cases 

Gil.