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

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majoco

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...and I thought you were going to let this sleeping dog lie... for a while anyway!

Sounds like good fun :)
 

zz0468

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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.

That's outstanding. Have you calculated what your ERP and antenna efficiency is? Base loaded, I presume, with that huge coil...
 

SCPD

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Oh, I couldn't do all that installation without at least trying it out-- albeit briefly... ;) ....(laughing.)
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A telephone call got a 48 hour release to use a frequency slightly below 137...not that I was putting anyone out- the frequency has no occupants...
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A couple more calls to my friend set up a listening post in New Mexico.
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Thus far I have done nothing with any telemetry to the transmitter, so I had no way, yet, of being at the transmitter site and remotely listening to its signal- However, my friend on her mobile ('cel) patch'd me back to the site, giving me feedback as to what she was hearing.
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On the night before my returning to New Mexico, we ran the test. We wait'd until after dark, the temperature outside the hut was a balmy 8 degrees F, electric space heaters brought the inside to a tropical 60 or so. The blizzard of the past several days had blown itself out-- it was a clear, windless night- the sky- crystalline- with a million stars against the Milky Way.. In other words, a bloody cold night to be out on a mountain side!
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I brought the tower into approximate resonance- tuning initially at 100 watts- straight continuous carrier. My friend report'd she could "hear something" (note the highly scientific method utilized here :) )
I increased the power to ~ 1Kw-- everything was holding together (ie; no sparks or arc's) but then, at full output--- all hell broke loose- With blinding crashes, the tuning circuit flared into a beautiful blue corona- looking for all the world like a Jacob's Ladder.... taking my breathe away ! ....when back'd off to 2Kw it became stable, but now I could hear crackling sounds outside the hut.
Looking at the tower and the large copper strap that connected it to the inside; practically every sharp point had a small corona sparkling in that clear, silent night. I can only guess at the RF voltage of my Tesla Coil. Those discharge surfaces,-- to be addressed this summer.....
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Now my friend was reporting a definite, clear signal... "a 5 to 6" (RST)-- again, note high degree of scientific precision. At his power level, I later model'd the ERP at 3.5 watts-- approximately 5db's above what would be allowed on 2200. I did not attempt that evening to calculate what the power output would have to be to achieve the 1 watt ERP limit for the ham band- but it was proven a signal could be heard from 0.1 Kw upwards.
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We then called it a success; -- I shut everything down-- and headed home to a roaring fireplace. :)
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........................................CF
 
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SCPD

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I have received a few inquiries about where my 137 Khz "Folly" stands - so here's my Official Update. :)
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I had to return the borrow'd 3 KW amplifier- which is just as well- the thing was way overkill besides weighing a tonne. Fortunately the power supply was separate- but I still needed help moving the bloody thing about.
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In its place I have the indefinite loan of a lab amp that covers the same frequency range- its a lot smaller and of lower power. This one is rated at 1.5 KW CCS duty using a pair of odd duck PA's, two 4CX350. I've one set of spares, but have no source, or $- for others. As their life span goes, so goes the "Folly."
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I decided to leave the antenna (tower) alone- with no further improvements.... ie: nothing better than the well casing and the secondary irrigation pipes for its ground counterpoise. I figure that being able to run high power, even for a calculated EIRP of 1 Watt from a 0.16% efficient antenna I have power to spare- I can "Brass it Out," so to speak- making up in watts what the antenna lacks in efficiency.
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Thus I have also decided to forgo any top loading coil or top hat counterpoises. Even at 40 feet in height, --> I don't work on towers<-- :)
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There are two 900Mhz telemetry units ready to run this remotely---- both sitting in boxes.... though I did mount one of the antennas- on the side of the well/transmitter hut.
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The rancher who leases my land says his burros, mules and horses just love hanging out about the tower's base- goodness knows why. Maybe it has something to do with my suggestion that he string up the couple of lines of white LED Christmas tree lights I gave him- they make the site look very festive at night-- if I were a burro that would be the placed I go too....... :)
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So there it all sits- awaiting either the day 2200 opens-- or I loose interest (rapidly occurrng) in this whole deal-- and leave it to the mules.....
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:)
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...............................CF
 
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majoco

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The rancher who leases my land says his burros, mules and horses just love hanging out about the tower's base- goodness knows why.

The same reason as the bullocks like the flagpoles on our rifle range - scratching posts! Everything else has got an electric fence around it!
 

RFI-EMI-GUY

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Could these longwave stations be configured to do something useful in addition to being a beacon? Like a low speed mesh network using a packet protocol. It would be cool to send tweets and have a list of nodes that carried the packet. Imagine a TEOTWAWKI situation. "Calling Citizen Z at Northern Lights , this is Atlanta, we got Zombies, over".
 

SCPD

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I never envision'd my 2200 setup as a beacon.. but I am afraid that seems to be what the band is destined for- at least for the considerable future. I feel there will be a dearth of people able to put a usable signal on it- that the vast majority will be the casual listeners with mediocre -to- worthless receiving capabilities..... and Please !, I say that in all charity, for most will not have suitable receivers/quiet locations/proper antenna/low frequency savy- and so on.... that's not to mention the very very few that will have transmitting stations that will be worth a hoot.
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160 metre's is a good example here. Anyone who has devoted time to it knows it is quite unique. The Enigma Band, I like to call it**
Propagation modes and results there can be phenomenal***, but few have the proper stations- or the interest- to find this out. Just tune across the band any evening- sure there are usually people there- but you are unlikely to hear anyone complaining about QRM. Now multiply that by an exponential and you'll have 2200.
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I jump'd on 2200 as a lark.... perhaps too much of a lark- though I am out very little $$ wise- so far...
I have proven this transmitter of mine can be heard quite well-- out to at least 250 miles- and knowing L/VLF very well, I'm confident it is capable of much more. When and if 2200 ever goes active, I plan to run it on QRS CW-- not the real slow stuff of the weak signal realm- but something someone could converse in. I don't like CW, but it will probably be the one mode easiest for many to use-- with a computer to encode/decipher for me. If I can't hear you with a signal worth an "RST" report- I can't hear you.
Transmissions will most likely take the form of Lonnnnng automated CQ's, very close to 136Khz- listening remotely in full duplex/QSK-
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We will see what happens.... there is definitely a operator Burn Out factor here to consider.
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Meanwhile, the Burros keep watch over the transmitter hut. I have some fencing to go around the tower and cable guys when things (may) go active- The RF arc's from the antenna at 1 Watt aren't noticeable like they were at 3.5- but I don't want my burro buddies burned ... and Majoco, you are right- they love to scratch themselves on the tower, and for some reason, chew on those tower cables............ :)
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................CF
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**I can't take credit for this term- I borrow'd it from this interesting article on 160 years ago.
http://solar.spacew.com/cq/cqmar98.pdf
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***160 is a favorite of mine- its true groundwave is the only thing I can depend on, that gets out of the mountains back home.
 

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SCPD

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DateLine: August-2200 Project Comes to a close.
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Kind'a premature, yes, but the heart of the "Folly"- the high power'd amplifier- I need long term for something else, so it was removed,-- with no plans to replace it.
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The JUMA exciter I fear will not be sufficient by itself. With the amplifier and 8-900 watts I can achieve the 1 Watt ERIP.. with the exciter's 50 Watts alone this becomes pathetic. Still, at some time in the future I may just put it on the air as a CW beacon-only.
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The Burro's, however, think the tower is a neat scratching post.... and so it will remain as theirs..... :)
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.....................CF
 

SCPD

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Ahhhh.. they moved far faster than I would have hazzard'd to guess!
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Thank you for the notification, PRC :) --
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I went to the the UTC site and in less than 2 minutes submitted my application. They say to allow 30 days for their decision, but since my transmitter will be miles from any power grid this shouldn't be a problem.
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Maybe I'll get the amplifier back, for as it is, with the exciter alone will only radiate an estimated EIRP of < 200 milliwatts... that almost fits into a Part 15 category (not quite, but it seems like it) -- but the experiment will continue!
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Again, a big Thank you !
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....................................CF
 
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RFI-EMI-GUY

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Is there any restriction as to what amateur classes can operate this band?

Sent from my SM-T350 using Tapatalk
 

SCPD

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Hi RFI... :)
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As far as my reading of the rules, its like the WARC bands- General and above .... :)

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...................CF
 

RFI-EMI-GUY

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Thanks CF. Another incentive. As far as the distance from power lines, is that to minimize mutual coupling and thus turning your tuning coil and nearby HV transmission line into a transcontinental dipole?

Funny I see no restriction on its proximity to electric fences or barbed wire fences.......

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SCPD

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The power companies use their lines for system data transmission. I guess if you already have the system infrastructure, use it.
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I know nothing about this technology, except it makes bloody hash out of my vehicle's AM radio reception practically everywhere I go -- I like to listen to KOB (KKOB) here in NM and KOA and KHOW at home in Colorado. Around here we have some super high voltage pylons that radiate the most unusual chorus of buzz's, chirps. whistles and burps . Fortunately I live far away from them- but they can't be avoid'd when driving anywhere- much to my unbridled annoyance (and if anyone could love that sort of noise it should be me ...lol)
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From the little I know, the power companies fear ham transmissions interfering with these signals. Again- I know nothing about power line signalling- but as an RF engineer, I can't see how this could be much of an issue at amateur power levels - Still, they don't want any ham activity that might cause problems.
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This is their requirements, as the primary users of these frequencies, and are pretty mild---> letting them know the frequencies and if the transmissions will be within a certain distance of their lines.... this can be fill'd out on- line in a few minutes:
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http://utc.org/plc-database-amateur-notification-process/
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Personally I don't think the power companies have much to worry about from hams. Few will try the new bands, fewer still will be able to muster the power necessary to make them work- and once they do, will find them barren waste lands for any activity.... not everyone will fit into this dismal profile-- but for 2200 especially; it won't be much of a 'hobby band.'
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Hmmmmm.... I would like to know why the power companies don't use other other ways for system controls.
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I'm sure they have good reasons- but I wouldn't hear them for the chirps on my AM radio. :)
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.................................CF
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AK9R

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From the little I know, the power companies fear ham transmissions interfering with these signals.
When power companies started rolling out broadband Internet over power lines (BPL), hams screamed bloody murder about the interference to the "standard" ham bands.

Now, hams are being given access to frequencies where they might cause interference to the power companies.

Anybody else see the irony of this?
 

SCPD

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An irony?...Indeed!... but these are the Big Boys and if you want to play in their arena some concessions must be made... ;)
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I can understand them, however. They see the risk as a ham station, right next to one of their pylons, with efficient 60 metre tall antennas pour forth a zillion watts into the Grid on 137 kHz's. Even though the legal limite is only 1 Watt EIRP, they see a risk. I won't go into how unlikely that would be for the average ham to effectively radiate 1 Watt to begin with, and vertically polarized at that- let alone induce that RF into a 300KV hortizonal set of wires up +80 feet. I know of hams that aren't the brightest bulbs in the chandelier , but I don't know of any stupid enuff to erect a tower close enuff to THAT to be much of a problem. Darwin address'd those guys in their tender infancy.
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Like I wrote in a few posts ago, my enthusiasm for this project has ebb'd. I haven't installed the telemetry or remote controls yet. The original 1KW amp will have to be 'reborrow'd' if anything meaningful is to happen. Still, I will put it on the air, QRP, for a few tests, since I've invested this much energy into the "Folly."
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I have even been thinking of reprogramming the exciter, dropping its power, and placing it on AM- in the 160-190kHz Part 15 band, playing continous stream'd music-- the '80's-- ("Blondie" is my favorite... :) )
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............................. "Radio Lauri, LongWave--- 186 on your AM Dial !!......" :)
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Smiles
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.......................CF
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SCPD

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I think you sum'd it up for me Krokus...
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There's a line from one if my favorite movies (I won't bore with the title) -- it goes something like this ;
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"You meant to do the right thing for this towne, Honey-- but maybe the world just doesn't need another golf course."
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...........And just what the ham world doesn't need, -- Another Beacon
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___________________________________________________________
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There is also another little caveat to a beacon on 2200. There is no provision for unattend'd operations..... (Part 97.203 limits them to certain bands, 10 metre's and above- plus there is a 100 Watt limit; though this Part says simply "100 Watts'- nothing about whether this is input, output- to say nothing of EIRP.)
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I'm not about to turn on a remote beacon that has to be 'attended' and sit beside it while does its thing.... especially out in a snowy horse pasture ..... :)
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I'll give this band a shot on QRP-- if it looks promising (though I have tested it on a non-ham frequency and have a pretty good idea what it can do DX wise)-- if promising, I'll get the amplifier back and complete its wireless remoting.
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I want this thing to actually "talk' to other stations- so I will use (computer assist'd ) CW. A lot of "if's."
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So far the UTC authority has been silent on my application for authorization-- a good sign.
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________________________________________________________________________________
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I'm sure I would be more enthused if I could play music over it as an unattend'd beacon--- :)
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....................................CF
 
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spongella

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LF - Try Listening in Now - Interesting Band

Exciting news about these new bands, even if you only have receive capability. Check your receiver or transceiver, you might have coverage. Signals have been on LF for decades, such as aeronautical/marine radiobeacons from 200 - 530 kHz. Listen for slow code identification for each, and if there is a constant tone in between id's then it's from Canada.

Originally this band was popular with mariners who used marine radiobeacons for radiolocation, using RDF radios. Haven't heard any of these marine beacons even though a few are still around on 285 - 315 kHz. Some even had AM wx info, miss those old beacons.

RDF radios, pretty much no longer manufactured can be bought on the second-hand market and have large rotatable ferrite antennas to hone in on beacons and can be a great addition to the shack.

You can also listen to Differential Global Positioning System beacons (DGPS) from 285 - 315 kHz. From what I understand these are old decommissioned marine beacons retrofitted for DGPS. ID them by a constant warbling tone. MultiPSK can decode them, and that's fun especially on cold winter nights when the band is much less plagued by QRN.

NAVTEX (Navigational Text) transmissions on 518 kHz can also be copied and decoded using free on-line software. Lots of marine wx info and warnings on these and again in winter LF opens up for better reception so try a hand at that. An alternate frequency for international NAVTEX is 489 kHz.

Not sure if LowFers are still on 160 - 190 kHz, these are license-free stations, usually with CW ids. Have not heard any lately.

Lastly are the Euro broadcasters, never heard one yet here on the East coast but surely others have.

A fun band.
 

SCPD

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No. I did not forget this topic....I said I'd be back..... :)
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The thirty plus days are up and past, and I never heard from the UTC.... so accordingly I can operate on 2200..... free and clear.... :)
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I went home this weekend- back to Colorado where,-- if anyone has follow'd my 2200 metre "Folly" they will remember that I have a station there.
Its at a remote ranch location-- a 45 foot antenna out on a mountainside in horse and burro paddock with a JUMA tranceiver, all installed in a hut shared with a deep irrigation well pump.
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Before leaving New Mexico I enlisted my friend Barbi to try our first ever 2200 metre "QSO."
We were to meet on 136.136khz (I choose that frequency- cute, No?... :) ).... slow speed CW , QRSS, if necessary.. computer generated and decoded... nothing fancy at all.
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My station was a paltry 50+ watts-- Barbi- sitting warmly ensconce beside her fireplace in New Mexico, using her codes, dialed up a transmitter site at an "undisclosed location" (but within 300 miles of me). We would co-ordinate over 'cel phones.
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"Remember, one watt ERP, Barb"
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"Of course it will be one watt !... you think I don't know that?"
...............(was I hearing a bit of laughter there??...)
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" I know the transmitter site you'll use.. dial it back, Girl Friend !....." :)
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So at the appoint'd hour we made contact-
Lauri, freezing her rear end off up in her burro pasture: Barbi, with her lap top in front a warm fireplace.
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The final score.... Lauri RST 5- 0 to 1 -9................... Barbi RST 5-9-9 ++ something over 20dbs.
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"Are you QRO, Barb??!"
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"But of course I am ! (tee hee!)"
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________________________________________
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So, my first ham 2200 contact. Now I can retire on my laurels. The weather is getting too nasty to play with this setup any more this year--- maybe in the spring I'll continue and hook up the 900 meg remote access.
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But it worked !-- and though my station's output in ERP power was in the milliwatts- (I can't/won't speak for Barbi)------
.......... it was a sweet success !
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...............................................CF
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