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Comment Re:Poor summary (Score 1) 468

I scanned that article and found no reference to why 13.56 MHz is a 'magic frequency' with regard to methane. With a wavelength of 22.1+ meters, it wouldn't have any sort of resonance with methane. In fact, the article goes on to talk about bond lengths and distances on the 10^-10m range, which is more like laser frequencies. My bet is that 13.56 MHz was chosen because it is a very popular ISM frequency for which there is plenty of COTS hardware.

Comment Re:Yeah, but how to get sleep (Score 1) 180

Any decent prospective partner would understand. It's better to sound a little like Darth Vader than snore like a freight train.

Funny story - a female friend, my wife and I spent 3 weeks in Scotland, and this was the first time I'd taken my CPAP on a trip. We spent the night in Edinburgh on Prince's Street (the Old Waverly, I think it was). I was relegated to the outer bedroom, and the ladies got the one with the two beds.

I was shocked out of my mind the next morning when I opened my eyes to see some guy in the room with me looking like he had the creature from Alien on his face. I hadn't realized when I went to bed that there was a full-length mirror on the wall next to the bed. Naturally that was me in my CPAP mask.

Comment Re:Yeah, but how to get sleep (Score 5, Interesting) 180

If he has sleep apnea, it can lead to a marked increase in his risk for heart attacks. With severe sleep apnea, your body senses your blood O2 saturation dropping and wakes you up in a panic thinking you're dying (seriously). That sort of 'night of 1000 deaths' leads to high cortisol levels and all sorts of other nasty things. I assume you probably already have, but urge him to at least have a sleep study done - that may show him that a simple CPAP machine can return his sleep patterns to normal. It quite literally saved my life.

Comment Re:Food exists, but you can't have it (Score 1) 419

The average (median) American eats 1.03 kg per day...

That's per per meal, right? ~sarcasm (Also a healthy dose of guilt - I'm one of those that would burn for years if you stuck a wick in me).

1.03 kg/day with a 70/30 split for calories from carbs+protein vs fat comes to 4944 calories/day. There must be a heck of a lot of fiber in their numbers.

(164.8 g of fat * 9 cal/g = 1483.2 cal from fat. 865.2 g protein or carbs * 4 cal/g = 3460.8 cal from protein or carbs).

Comment Re:I agree with the end goal, Bruce (Score 1) 89

If it's strong enough you can see SSB. Given the bandwidth, the power is spread pretty thin (it's hard for me to imagine I said that - SSB is wide? Being narrowband was a selling point over AM and FM. How far we've come!).

For the record, I'm also a digital kind of guy, and have made a fair number of JT9-1 contacts recently as well as being an FSK441 lurker.

I think we're in fierce agreement. One of these days I hope to work you on the air. 73, Bruce!

Comment Re:I agree with the end goal, Bruce (Score 1) 89

Thanks for the reply, Bruce.

You said, "CSMA doesn't work that well on HF. Sometimes you should be able to share a frequency with distant operators even though they fade in and out, etc. However, it makes sense if you are doing automatic link establishment."

The reason I mentioned a listen-before-transmit was to try and mitigate the unintentional-yet-preventable interference that would undoubtedly occur if SSB and data modes where thrown together cheek by jowl. All it would take would be a DXpedition working split to cause havoc. In the case of an SSB DXPedition, I'd hope that the human ops would be listening on their tx freq to prevent them from transmitting over a data QSO. This does not always happen, I realize. Given that some?/many?/most? data operators have the audio turned down and are busy looking at their rx freq on waterfall instead of actually listening, they could unintentionally QRM an SSB signal as they go "UP UP UP" with the VFO to be heard.

I agree your proposal is ambitious, but I think it's probably the right thing to do given the surge in popularity and utility of the newer data modes.

Comment Re:Be careful... (Score 4, Informative) 89

...it could be fertile ground for experimentation...

It is a fertile ground for experimentation! You need look no farther than the recent influx of extremely spectrum-efficient modes developed by K1JT. He's developed modes tailored for most any propagation mode/band including meteor scatter, moonbounce, etc.

The newest of the lot, the JT9 modes, are capable of decoding signals as far as 42dB into the noise!. The fastest JT9 mode takes 1 minute per transmission but can decode at a S/N of -27dB - that's noise with 500x the power of the signal.

Take a look at the WSPR page - on it you can access a database of WSPR transmissions, some of them at amazingly high km/Watt ratios.

Comment Re:I agree with the end goal, Bruce (Score 1) 89

vlm,

I agree completely. The current 'gentleman's agreements' (aka voluntary band plans) do work and can continue to do so as long as they're also amended to reflect the new bandwidth-based FCC rules and are still recognized by the FCC in instances of interference. A quote from Riley Hollingsworth: "Band plans are voluntary in nature," Hollingsworth acknowledged in each of the similarly worded letters. He said the FCC depends upon voluntary compliance because it minimizes the necessity for the Commission to be called in to resolve amateur problems. "Where interference results from band plans not being followed," Hollingsworth continued, "the Commission expects substantial justification to be shown by the operators ignoring the band plans."

According to this Wikipedia entry, region 1 already has a bandwidth-driven bandplan and hints that the RSGB's plan (that the UK gov't accepts as official) will too.

The IARU's suggested bandplan for region 2 already has suggested bandwidth limits and encourages member states to adopt it.

Comment I agree with the end goal, Bruce (Score 3, Interesting) 89

The end goal of moving toward more spectrally-efficient digital modes for all forms of communication is laudable, but I think that there still needs to be some 'semi-official' protection for the traditional SSB phone modes while they're still in widespread use. Most robust digital modulation schemes are fairly immune to interference from adjacent SSB voice transmissions; unfortunately the converse is not true - my Mark I ears are not immune to nearby digital interference. As long as we still have band plans that encourage the separation of all digital modes from the analog modes, I fully support your proposal.

A question, though: How does spread-spectrum fit into your bandwidth-based plan? Do you consider the bandwidth to be what's used by each individual chip or the SS signal over all its carriers?

How do you feel about introducing a CDMA-esque automatic listen-before-transmit rule for computer-based digital modes, particularly with the growth of unattended stations?

PS - There's a typo in item 79 in the 20m, 6kHz section of the proposed bandwidth table - you have the lower limit as 1.150 MHz instead of 14.150 MHz.

73 de K4DET

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