New MF/LF ham bands - with a catch...

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majoco

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Bearing in mind of course that EIRP is a notoriously difficult thing to measure especially at low frequencies - usually done by calculation as you (CF) have done. Perhaps the "E" should stand for "Estimated" rather than "Effective".

I wonder why they went for EIRP anyway, when Field Strength in µV/m is more easily measured - but of course at 2200m you'll need a calibrated quarter-wave antenna........ :)
 

majoco

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CF - your horse paddock sounds like an ideal site, perhaps good for a "Marconi Special" - his first antenna at Poldhu.....
 

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SCPD

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Hi Majoco--
A neat picture of the Poldhu station's aerial. I don't think my ambition is anything like Marconi's :) ..... and I can take a warning from history.. and his experience-- That one collapsed before it could be tested... so did the first American station's.
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There has been considerable speculation as to what frequency Marconi used in his first Transatlantic transmission**. Marconi himself was always vague about it, though analysis of the antenna design (the frequency determining parameter) lead consensus to 850 Khz.
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I have been fascinated by the early history of radio- I have a great aunt who was one of the first "Marconi Girls"-- as she called herself. Thru family histories from my grandfather (SK, also a ham)- I have gleen'd a lot about those early days of Spark Gap.
And though I know the physics behind Spark technology, I would be lost if sat down with the Morse key in front of one of those transmitters..... just what little 'tricks of the trade' did they know to make them 'talk?' I'd love to try it, however.
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I have several "QSL" cards from my aunt- Victoran era postcards, very unlike the types exchanged today- but with details of conversations between operators -informally made. Apparently the Marconi company frown'd on such activities, but did little to discourage my aunt or the other 'girls.' They seem'd to like to jump up above 300 metre's- away from the usual traffic frequencies- when time was slack, and chat briefly... the first true 'hams.
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Yes, that EIRP issue is a bugger. I haven't access to a calibrated meter for 2200.... I don't know of anyone one who has- or anyone who could make the difficult measurements at that frequency that would be meaningful. So I am going with my computer models- since at the very low efficiency of my antenna, whether its input is 500 or a 1000 watts, really won't make much difference- a few db's won't raise many eyebrows... though I'll stand by my calculations if anything "official" becomes necessary.
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I drove out to the pasture to take a quick look about- there is a foot of snow still on the ground, and higher drifts beside the hut.... it will be a few more weeks....
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...................................CF
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________________________________________

** https://www.ieee.ca/millennium/radio/radio_differences.html
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Below is Fleming's original drawing of the Poldhu spark transmitter
 

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majoco

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Make a spark transmitter! Wow - comparatively easy to do...

Spark Transmitter

....but the complaints from the hams down the road!

Another article suggest that although the intended wavelength was around 135kHz, reception was actually on a harmonic - and about 12kW power.

My Dad worked for Marconi Wireless Telegraphy Co. as it was called from 1936 or so to the late 60's. He had something to do with the prototype design and construction of the Type "A" Mklll suitcase spy radio along with a neighbour Fred Turner G3VI at Chelmsford New Street works. I have one here that still works although I haven't tried it recently.
I did my spell with Marconi Marine 1964 to 1969 until I realised the promotional ladder had only one rung!
 
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majoco

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Oops, here's the pic I intended to add but dem phat phingers got in the way....
 

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SCPD

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Spark Gap... (smiling) ---- I have a confession.
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While I would love to sit down to a real Spark station-- one right out of the early 1900's, --------adjusting the spark, setting the wavelength,---- trying hard not to get electrocuted--- I have (and this is the confession) ----- Play'd with Spark Gap- as in: On-the-Air type play'd with.
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This was quite a few years ago, in a land far-away---- way outside the bounds of any agency that may have objected. It was during a period of down time on a project-- we had burned out a test radar and where awaiting some replacement parts--- that I and some engineers decided to experiment with "Spark.'
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An idle mind is the Devil's playground.
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It was the combination of a tropical setting, some techno-geek's midnight discussion-turned-to- SparkGap, -- fuel'd by Drambuie, .... all this lead to a-- "Lets try it."
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On our island, the US Navy- the previous occupier, had left a small warehouse full of things to get in truble with.. namely aircraft ignition coils (we won't mention the 25mm aerial distress flares... :) )
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We wired up a transmitter, feeding the primaries with key'd AC. The coil's secondary, with the spark gap, fed a tank circuit dipped to ~1000 Khz-
A secondary coil around the tank fed a Pi network, to giving us a bit of 'filtering' to better notch the 1000 Khz. A long wire, semi vertical antenna, and a longer counterpoise ground completed the setup.
Tune up was easy.... In 'key down,' we tuned for the strongest signal, as received over a portable AM radio. Someone decided to look at the transmitter on a spectrum analy'zr and found our signals suprisingly narrow-- it only wiped out a few hundred Khz's +/- 1000Khz , at a range of a hundred feet.
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"Not bad," we figured.
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Fortified with more Dambuie, and a UHF handheld to report back to 'Base,' the range about the island was explore. Signal strength varied from "590" to "~540" (note the Zero for tonal quality.... but what else is to be expected? this was Spark !) Range; over a one and a half miles.
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A second transmitter was constructed a few days later. This was take by a Zodiac to a nearby island in the atoll, and a "station" was established. Range: now about 3 miles. With portable AM radios for receivers: a QSO (!), between two separate Islands----we were just like Marconi!
More Dambuie!
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No offical callsigns, of course... signal RST's: something like "52-3 by Zero."
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We did it ! ................. QSL cards?... they are still in the mail.
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******Your Tax Dollars, Hard at work******
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_______________________________________________
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On a more serious note;
That's a great photo of the spy transceiver. Majoco, and your family history behind it. :)
When I look at that radio, I can just imagine being a covert partisan-- hiding in a Paris attic,-- tuning it, hoping to make my contact to the UK...... The Nazi's, all the while DF'ing me .... a death sentence if I'm caught.....
Oh, how I can close my eyes and imagine it! ......Smashing!.... :)
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.............................CF
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_________________________________________
Hey, guys, I tried to stay on topic--- this did discuss something MF/LF? :)
 
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majoco

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On our island, the US Navy- the previous occupier, had left a small warehouse full of things to get in truble with
In the mid - 80's we were tasked with removing the American caretaker from Canton Island, sort of halfway between American Samoa and Johnson - to replace him with a caretaker from Kiribati. The runway was just about shot, the mangroves had ripped up the crushed coral surface allowing us just enough length to come and go. All the US guys had been pulled out about 7 years beforehand and it was a bit like the Marie Celeste - a ghost town. It had been a mid-range tracking station for missile firings, huge dish antennae, support equipment, de-salination gear, workshops, sheds full of rusty GMC 6-wheeler trucks, racks of electronic stuff, mainly HP, even the Motorola handhelds still in their cradles up in the tower, turned on and ready to go, GPU's all lined up on the tarmac. The outgoing caretaker had a 40 gallon drum of crayfish that he wanted to take back to US Samoa - fortunately we were strictly weight limited - the smell was pretty bad! I would have loved to have taken a barge and cleared out all the stuff there! Oh, well, another opportunity to be a millionaire comes and goes!
 

krokus

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Reading all this reminds me of touring the VLF transmitter, at my first duty station. There was nothing small about that place.

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n9mxq

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Seems to be another wrench in the works. From todays ARRL Letter. Been following this thread, but not participating..No way I've room for an antenna that would work on these
Important Notice -- New MF and LF Bands are Not Yet Available to Use!

The new 630-meter and 2,200-meter bands are not yet available for Amateur Radio use. The effective date of the recent FCC Report & Order (R&O) granting these allocations has not yet been determined, and until the start date has been set, it is not legal under an Amateur Radio license to transmit on either band.

The fact that the new rules contain a new information-collection requirement -- notification of operation to the United Telecoms Council (UTC) -- complicates the matter of determining an effective date. According to the FCC R&O, the Office of Management and Budget (under the Paperwork Reduction Act) must first approve the information-collection requirements in §97.303(g)(2), which must be in place before radio amateurs can use the new bands.

Once that happens, the FCC will publish a notice in The Federal Register "announcing such approval and the relevant effective date," the R&O said. ARRL will announce the UTC notification procedures and the effective date to use these new bands as soon as these are known.
Guess there's no need to listen down there quite yet ;-)
 

SCPD

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Well, now THAT's a fine How-Do-You Do !!
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Thanks for the heads up N9MXQ. :)
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I called my contact at the FCC and he said, basically the same thing-- "Hold your horses, Lauri !."
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Now I've got my neighbor delivering the tower section next week, and my Cowboys lined up to place the bloody thing........ I'm going ahead anyway,
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Heck...** if it all doesn't pan out I'll string Christmas lights from it and let the horses be entertained by the twinkling bulbs..... Lauri's Folly.. :)
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.....................CF
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** I used a bit harsher 4 letter word ;)
 
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SCPD

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Thanks for the kind sentiments, MXQ... ;)
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I really should have research'd the legal status better before I jumped off, full scale, into this 2200 metre project.
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I know that's its just a matter of waiting for all the Bean Counter's to dot the "i's" and cross the "t's" ----
But I work in this stuff---- I should have known better.
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I am afraid at times, I take on the attitude of a character in one of my favorite old movies- a chap named Gold Hat. His name is unknown, but this character isn't.... he lives on, decade after decade... Remember him saying to Humphrey Bogart:
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:......................" Badges ?..Badges?!... we don't have to show you No Stink'in Badges !!" **
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I forget sometimes that there is a vast portion of the radio spectrum regulated by another Federal agency.... Ah Well......... I will be patient..... :)
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Thanks again
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...............................CF
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._________________________________________
** The treasure of the Sierra Madre (1948)
 

n9mxq

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If I had the space, and funds, I'd be in the same boat.. Just itching for the authorization to xmit...
 

majoco

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Perhaps the clue lies in the very first sentence of the "SWLing Post" article....

Hams in the U.S. will soon have two new bands on which to operate, experiment and contribute to the collective knowledge of “the radio art.”

"Soon" is a comparative word, in this context probably just before the second coming.
 

SCPD

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My 2200 project will continue, despite this little setback.... Its just a matter of time before the band is officially released in the US ....(Sayeth the born Optimus.... :) )
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In the meantime, I'm having the tower base and guy anchors pour'd next week, and the tower placed as soon as the concrete is stable. I've got the components to wind a large ceramic loading coil for the 'top hat'......but I don't see any urgency to go much beyond that right now....Besides, I've a garden to plant and some mountains to climb :)...Spring has finally ! arrive in these mountains!
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Telemetry is my middle name- and when ("If"...???...laffing) 2200 is released I'll have a 900 Mhz link ready. I'll likely install and test that link soon. The immediate plans call for nothing more exotic than a slow speed CW beacon-- if my friend back in New Mexico can hear it, I might actually converse- though I don't like Morse. Digital is definitely in its (questionable ?) future.
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So Guys, until I have something more is to say, I'm closing on this 2200 topic.
.......I'll leave you with a photo of the ultimate old fashion'd Low Frequency transmitter-- suitable for portable or mobile operation---smiles ;) **)
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................................................CF
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_____________________________________________________
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This is an Alexanderson Alternator , located in Grimeton, Sweden. It is still operational..... frequency 17Khz. Every year its put on the air briefly for test transmissions- call sign SAQ. I visited it several years ago... a real neat example of the transistion from the mechanical to the electronic in radio. Also a beautiful, functional example of what is now the popular art form; "Steam Punk."
 

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N4GIX

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Thanks, C-F! Here is a very interesting article with one listener's experiences with receiving SAQ, along with a photo of the antenna array.

SAQ - Alexanderson Alternator
The radiating system is massive as well. It is composed by six 127 meter high masts.
The masts are placed at 380 meter intervals and at the top of the 46 meter high masts, long crossarms are attached in order to carry the 12 wires feeding energy into the six vertical radiating elements.

More info here about both SAQ, but also the one the USAF had operational until circa 1960 at Marion Massachusetts, call sign AFA2.
http://jproc.ca/radiostor/aalt.html

Further describing the antenna at SAQ as 2,280 meters (1.42 mi) long. Wow!
 
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TomServo

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I'm fascinated by all things LW but this will be a no-go band for me. My local utility uses PLC on their high tension lines and those run less than 250 feet from where I live. They blitz the band in a lot of places. Amateurs get the band on a "secondary basis" to PLC, so there's no way I could do this legally.

Oh well. There are several active users of the bands already, via experimental licenses. I haven't heard anything yet but I do listen from time to time with WSPR.
 

SCPD

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Tom , one thing you might consider is researching if there are any remote receivers available to hams, and listen there. I have access to a number of government remotes, and plan on using them, though my transmitter location has virtually Zero noise on 2200.
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There is also something of a rule added to these frequencies; about being so-close to certain types of power lines-- notifying the power companies... possible 1 km distance between things..... that may limit your ability to transmit.
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Like you alluded to; this is a band for the not-so-faint-at-heart-- it will be populated (count them on your fingers) by experimenters (and fools, like me... :) ) for however long it takes to send us fleeing back to the high'r frequencies.
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............................CF
 

SCPD

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A Coyote 2200 update.
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The tower is up--- all 45 feet of it, sans the top loading coil. The transmitter is set and the borrowed amplifier - connected. The matching circuit is a simplicity of design... a huge coil with a very large variable capacitor... most likely to be replaced with something better.
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I took it briefly out of the 2200 ham band to a nearby NTIA frequency I can access and ran a brief test-- 2150 watts into the antenna, a narrow band frequency shift test signal..
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And.....
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Bingo! .............. RST 569 at ~250 miles.
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Now it can all sit until the day 2200 is officially released. That will give me time to work on that top hat loading coil. Besides, we've a Spring blizzard blowing up on the mountain, and it will be awhile before I'm back in Colorado..... it can sit--
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On another note: in talking about my "Folly" with a colleague, he reminded me that frequencies below 9Khz are not regulated. Yes, I know- that is Really Low-- but-- experiments are being run there all the time and surprising thing occur.... plus, there are no rules...
I throw that out for what its worth-- plus don't discount the 160-190Khz allocation under Part 15--
The VLF and VeryVeryVLF's are a blossoming experimenter's playground.
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So-- awaiting Spring to finally settle in... and the FCC to act.................. :)
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.................................CF
 
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