HFU HF Underground

General Category => Huh? => Topic started by: ThaDood on July 13, 2023, 1757 UTC

Title: Market Makers” Want to Expand Their Use of Shortwave?
Post by: ThaDood on July 13, 2023, 1757 UTC

Seen on SWL'ing, but on RW as well.   https://www.radioworld.com/tech-and-gear/market-makers-want-to-expand-their-use-of-shortwave   Interesting PROP Maps there.

Title: Re: "Market Makers" Want to Expand Their Use of Shortwave?
Post by: ~SIGINT~ on July 14, 2023, 0043 UTC

If you are technically inclined, be sure to download a full copy of the petition found at the following URL:
https://www.radioworld.com/wp-content/uploads/2023/07/5b410673-0cbd-467b-8ea9-06d7808c7924.pdf (https://www.radioworld.com/wp-content/uploads/2023/07/5b410673-0cbd-467b-8ea9-06d7808c7924.pdf)

There is some very interesting reading and charts with regards to propagation, noise figure etc ... and the use of VOACAP for the modelling.

Title: Re: Market Makers” Want to Expand Their Use of Shortwave?
Post by: ~SIGINT~ on July 15, 2023, 0158 UTC

P.S. Don't believe everything you read from the coalition who put the petition together. They are out to make a buck and bamboozle the FCC with their slick technical submission which reads like a University term paper.

Case in point ...

Quote

It used several frequencies, with 20 kW transmit power and a transmitter bandwidth of 10 kHz.

The image bellow is of a typical HFT. No where near 10 kHz transmitter bandwidth. Try more like 60 kHz transmitter bandwidth. Operating in a non-interfering portion of the bands ... I don't think so, at least not in this case.

(http://www.milspec.ca/board/img/2023-07-14_214430.png)

Title: Re: Market Makers” Want to Expand Their Use of Shortwave?
Post by: Charlie_Dont_Surf on July 19, 2023, 2310 UTC

Quote from: ~SIGINT~ on July 14, 2023, 0043 UTC

If you are technically inclined, be sure to download a full copy of the petition found at the following URL:
https://www.radioworld.com/wp-content/uploads/2023/07/5b410673-0cbd-467b-8ea9-06d7808c7924.pdf (https://www.radioworld.com/wp-content/uploads/2023/07/5b410673-0cbd-467b-8ea9-06d7808c7924.pdf)

This gave me a chuckle (bottom of page 6 into 7):

Quote

Given these limitations on use of the 2-25 MHz Band, it comes as no surprise that
the introduction of innovative 2-25 MHz Band technologies for private sector use has languished
for decades. Indeed, the Commission’s Universal Licensing System (“ULS”) illustrates the
extent to which the 2-25 MHz Band is under-licensed. Of the 21,507 active licenses in ULS for
2-25 MHz Band frequencies, only 61 are licensed for Industrial/Business Pool use pursuant to
Part 90.9 In contrast, of the 215,980 total licenses in the 450 MHz Band (450-512 MHz), there
are 163,624 active licenses for Part 90 Industrial/Business Pool use.

Without discussing any technical reasons why the number of licensees might be as it is and casting aside the differences between HF and UHF, the assumption must be that the 2-25 MHz band absolutely should be jam packed.

Title: Re: Market Makers” Want to Expand Their Use of Shortwave?
Post by: ~SIGINT~ on July 31, 2023, 0244 UTC

Quote

Operating in a non-interfering portion of the bands ... I don't think so, at least not in this case.

I just captured this image of an HFT on the back door of DDH 9 (11039 kHz) and who knows what else in between. DDH 9 is still punching through good readable. Both 20 kHz wide data / control HFT channels are clearly visible.

(http://www.milspec.ca/board/img/2023-07-30_223123.png)