Rescuers attempting to retrieve a cave explorer made use of a QDX-M built for the 2200 meter band (136 kHz) which, evidently, will allow communications through solid rock.
The rescue was successful and can be read about here:
According to Hans:
"There is a request to make the QDX-M firmware operational down to 88 kHz which is where the UK and European cave rescue services have an allocation. I will try to get that done in the next week or two.
Me, I slept well that night... Well for 3 hours at least, after I worked on fixing the YOTA youngster's QMX+'s until 4am..."
I'd like to know what type antenna was used for the operation.
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At 0:55 you see kind of a square antenna. I guess that the wire around it is many windings of wire. Interesting though. Tnx for the video John. 73, Bas
ReplyDeleteI guess they lug one of those into the cave as well? The whole thing has captured my curiosity about LF/VLF. I'll bet Hans will soon be offering a 2200m QDX-M to the masses...
Delete73,
John
Its a loop antenna for VLF.
DeleteIn the meantime, Multus SDR has 630M and 2200M radios on their menu. I have also been thinking about these bands lately but the last thing I need is more radios, I haven’t even gotten my Anan 10E online yet!
DeleteIt's too bad all this SDR stuff wasn't available back in the days when LowFER's were a thing on 160-190 kHz. You didn't have to be a ham to use it but the only mode was CW with a 1-watt max output.
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