Starting in April 2017, I will conduct a new quarterly column in CQ magazine entitled, "MF/LF Operating: Life Below the AM Broadcast Band" where I discuss a number of topics to enhance operating on 630-meters and 2200-meters. The column will be published in April, July, October, and January and the first article is an introduction along with some tips to help prospective operators get started, with a focus on receiving strategies. I will tackle common transmitting antennas in July and generating a signal / making power in October. My hope is to also begin discussing the concept of radiated power in the October column but we will see how far I get. This topic is deep enough that it may require its own dedicated article. Send me an email at the address above if there is a topic you would like to see handled in the future.
The archives from the MF and LF presentations at Hamcom 2016 can be found here: http://njdtechnologies.net/hamcom-2016-mf-and-lf-presentations/
It was an honor to be interviewed by Eric, 4Z1UG, on the "QSO Today" podcast about my ham history and 630-meter activities. It can be heard at http://www.qsotoday.com/podcasts/kb5njd
Wondering why my 630-meter station might be off the air at any given time? Check the lightning map. WG2XIQ is QRV all year around but because of my high elevation, tall antennas and the prolific lightning storms in Texas, I pick and choose my battles carefully. If WG2XIQ or the 472 Grabber are QRT right now, it will be QRV again when it is safe. Thanks for your patience and understanding!
Lots of additional information at my website: http://njdtechnologies.net/ . Special thanks to Larry McFarland, KY5S, for making it possible.
Visit my new 472 kHz medium wave screen grabber page at http://njdtechnologies.net/472-grabber/
This is one of the full -band screen grabs showing WG2XIQ (yellow) followed by WG2XXM (line) in addition to another signal around 477.9 khz
KB5NJD / WG2XIQ operating position as of Summer 2014
I have completed 9-Band DXCC, DXCC MIXED/PHONE/CW, 5-Band WAC with 160m and 30m endorsements, WAZ CW, and WAS CW. I have also completed 160 meter WAS and 160 meter DXCC on CW. I have also actively worked on 160m WAZ in the past and lack just a few zones. Also numerous awards for CW Sweepstakes, IARU HF World Championship, Low Band Monitor WAC, The Stew Perry Topband DX Challenge and Texas QSO Party.
My current passion is medium wave operation on 630 meters as a Part 5 experimental station with the callsign WG2XIQ. Station details below.
I was first licensed in 1989 and have held an Extra class license since 1990. I also hold General Radiotelephone and 2nd Class Radiotelegraph commercial operators licenses (with radar endorsements) and do some engineering consulting work as time allows. I'm currently working on a PhD in Physical Chemistry and have a fascination with heavy and super heavy elements and their synthesis.
I operate CW almost exclusively, but do operate a few digital modes on 630-meters. I like QRQ (Fast) CW and find myself ragchewing more and more these days. I prefer my Bencher iambic paddle, which I originally purchased from QRP Hall of Famer Jim Cates, WA6GER, when I was a young ham but also own a Vibroplex standard original bug. SKCC# is 13739 if we happen to QSO when I am using the bug. I also have a Heathkit 1410 paddle/keyer combo that feels very nice and I use that with my 630-meter station.
Primary transmit antenna for 630-meters is an 80 foot tall vertical with 300 foot top loading wire over 150 - 100-ft radials. The vertical is resonated by a motorized variometer controlled from within the ham shack. A matching network is in place to allow the system to also be used on 160-meters. Antenna base current monitoring of the 630-meter vertical is done remotely from the hamshack. Short beverages in popular directions, K9AY Terminated loops, multiturn resonant loops and coaxial shielded loops are used as low band receive antennas.
I enjoy MF and LF propagation research and have spent a significant amount of time playing with WSPR, an automated beacon system on steroids. Learn more at http://wsprnet.org/drupal/
I recently went back to paper logs for everyday QSO's. Its just more enjoyable for me to be able to thumb through those logs and review contacts. I still use electronic logging for contests and even transcribe the paper log to electronic logs if I or someone else need an LoTW QSL. I still prefer getting snail mail QSL cards. Its an amazing feeling of accomplishment when you go to the mail box and that card is there from some far off place. Its also the final courtesy for any QSO.
Main HF station: Yaesu FT-1000 Mark V Field, Ameritron AL-811, various ICE bandpass filters and receive processing systems
Portable station: Elecraft KX3 with a variety of portable antennas including End Fed's and doublets for routine portable operations. I've also been building and experimenting with small, portable magnetic loops. For ease of setup and tuning, in addition to really solid on-air performance, this setup is tough to beat on the high bands. Performance has been surprisingly good on the low bands as well. Mag loops are certainly worth a look if you are looking for a high performance portable solution. I also have plans to use the KX3 as a driver for a portable 630-meter operation in the future. Maybe even kayak mobile. I really enjoy the outdoors and operating portably. Having participated in portable ops originally in the early to mid-90's while working on my undergrad, for some reason I stopped and relegated myself to operating primarily in the ham shack for nearly 20 years. It's really nice get back out in the field where it feels like Field Day everytime I set up. One very new experience for me is pedestrian mobile. Use of low cost Walmart "waist packs" (formerly known as "fanny packs"), one can easily carry a small battery and rig like the KX3 in addition to a light, portable antenna (vertical or mag loop is common). Performance has been very good so far and I always look forward to hiking and running stations on CW at the same time. You can see me in action at http://njdtechnologies.net/hf-pedestrian-mobile-at-cedar-hill-state-park/ . Perhaps there is room for 630-meter pedestrian mobile in the future...
630m station: Receiver: Yaesu FT-920 and a HeathKit HD-1420 VLF upconverter with a homebrew bandpass preamp or a direct connection to the receiver (no external upconverstion). Transmitter PA: single IRF540 MOSFET running class-D, max output 125 watts. A zero degree hybrid combiner is also available to allow two separate, identical IRF540 amps to be combined for nearly 250 watts of power to the coax (approximately 10 watts max ERP possible on current antenna system). Output is actually controlled by separate variable, current-limited power supplies. One way of operating CW is via homebrew CMOS-based VFO with 3.6 MHz LC that is buffered and divided by 8 to give 12v P-P at 472kc-479kc to drive main PA. PA/VFO are GW3UEP's design http://www.gw3uep.ukfsn.org/index.htm. Transmit downconverter for CW and PC-based digital modes uses a 3.2 MHz LO and RF from the FT-920 between 3672kc and 3679kc to generated a difference frequency of 472kc-479kc utilizing a 2N3904 transistor as the mixer. This is a variation on the design of G3XBM http://sites.google.com/site/g3xbmqrp/Home/472khz-transverter . Thanks to the ITU, the ARRL, and the 630-meter research group for their efforts to make this new band possible in the near future.
I have written many articles chronicalling the construction and operation of my 630m station and would be happy to make those available on request. I am also available to speak at your club meeting or convention. Just email me to discuss scheduling.
On May 1, 2013 I began using the MF Solutions 630 meter transmit downconverter as my primary signal source on 630-meters for CW and PC-based digital modes. Developed by John Molnar, WA3ETD/WG2XKA, this board has drastically improved spectral quality and can produce 20-22 watts with a 12v and 2 amp power supply. Additionally, the board's output easily interfaces with my larger PA. The kit utilizes few parts and has a number of very low cost add-on options, including a GPS-disciplined LO input port. I am a very happy end-user. Contact John Molnar directly for details at WA3ETD@gmail.com. Also check out John's webpage for information on his station at https://wg2xka.wordpress.com/
On February 25, 2014 my original MF Solutions transmit downconverter was retired to backup status and replaced with a new MF Solutions downconverter that has the 10 MHz external reference option installed (pictured above). The addition of a Trimble Thunderbolt GPS Disciplined Oscillator has stabilized my output frequency tremendously. Rather than chasing two moving targets (FT-920 oscillator freq + crystal LO freq on the original downconverter), I now only have to worry about the stability of the FT-920 oscillator. When warmed up, the FT-920 shows to be about 15-20 Hz high using the stock oscillator which is fine as long as it is predictable. Removing the instability of the crystal LO in the downconverter by adding the thunderbolt has been very nice when operating the low baud rate computer-based digital modes. This system is also used to generate CW signals.
For Christmas 2013 I received a Hans Summers "Ultimate 3" DDS/Arduino QRSS kit. This kit, including LPF for 630m and 2200m and GPS module, as well as the arduino, DDS board, and display were under $70 shipped. This is a neat little kit and gives me some opportunities to play with very low S/N modes that I don't otherwise have the stability to operate. While I still consider the MF Solutions converter and GW3UEP QTX based system the basis of my QSO operating, this neat little kit covers all bands from 0-40MHz and adds another option to my tool kit. Square wave outputs make driving an amp a breeze but the LPF allows you to put a virtually pure sine wave on the air from 300mW to 2.5 watts with the additional PA FETs and higher PA voltage. Details at http://www.hanssummers.com/
Effective 9/12/2012 Part 5 experimental license WG2XIQ is on the air between 465-478 kHz
WG2XIQ grant was renewed June 10, 2014. Modification was filed on July 7, 2014 to increase frequency range to 465-480 kHz, allow 10 watts ERP on all modes, and add 62HJ2B as an operating mode (PSK-31). Modification granted on August 12, 2014.
WG2XIQ grant was renewed again on July 12, 2016 until September 1, 2018.
Typical 630m frequencies include:
CW calling / CQ frequency: 474.0 KHz or 474.5 KHz are common here stateside. Many stations in EU operate near 472.5 KHz.
WSPR: 474.2 KHz USB Dial Frequency + 1400 - 1600 Hz
JT9: 474.2 KHz USB Dial Frequency + 1000 - 1200 Hz
Note regarding WSPR: It is not enough to simply set the radio on 474.2 kHz and open the WSPR 2.11 program. The proper band must be selected AND the text boxes marked TX and Dial on the left hand side of the window must be accurately populated in order to allow the decoder to listen in the correct portion of the passband. Set "Dial" to ".474200" and "TX" to ".475700". Even if the band is very noise, resist the temptation to use filters and noise blanker. The program has algorythms in place to deal with noise. Using these can inject artifacts into the signal which can prevent decodes. The system really can hear signals weaker than you can hear. ALSO, 99% of the problems that people have with WSPR is that their clocks are not properly synchronized. WSPR needs a very accurate PC time. Windows Internet Time update, even with the registry hack implemented to update hourly, is not very accurate because of the high degree of failed updates that occur and there is no process for retrying another time server address automatically. Consider using a program like Dimension4(http://www.thinkman.com/dimension4/features.htm) or Meinberg NTP (http://www.meinberg.de/german/sw/ntp.htm), both available free online.
Check out the ARRL's 600m research group at http://500kc.com/ .
600 meter research group mailing list: http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com
File a 630m reception report: http://w5jgv.com/enterlogs.htm (Note: Its a good idea to email me a direct report also, particularly if you are requesting a QSL card - thanks!)
Check out the ON4KST "2000-630meter kHz chat" where many of us arrange skeds: http://www.on4kst.org/chat/index.php
Read the ARRL's account of my 2014 TX --> VK Transpacific transmission on 630-meters: “US to VK Transpacific Reception Reported on 630-meters”
Why not see what your existing antennas can hear on MF? You would be surprised what works sometimes. Or have a look at these links with info on receive loops and preamps:
VE7SL's lowband notebook: http://members.shaw.ca/ve7sl/
G4FRE/WW2R's table top, multiturn RX loop: http://g4fre.blogspot.com/2013/10/building-477khz-loop.html
K9AY's Terminated loop page: http://www.hard-core-dx.com/nordicdx/antenna/loop/k9ay/k9ay_orig.pdf
Looking for some information on antenna calculations associated with 630m? Check out the website of Neil, W0YSE/WG2XSV: http://w0yse.webs.com/wg2xsvpage.htm
Check out the 630-meter BSEF 8-circle array constructed at the NO3M/WG2XJM contest station: http://no3m.net/index.php?page=600m-8-circle . This monster fills 30 acres!
Here is the most recent addition to the WG2XIQ receive arsenal - the VE7SL multiturn RX loop with single turn pickup (See VE7SL link in the above section to get to Steve's site for further details). This is nothing more than a parallel tuned circuit with an isolated pickup consisting of about 15 turns, each 19 feet long with 1 inch spacing. A parallel capacitor bank of around 250 pF resonates the system. I use a relay to short across the loop while transmitting to avoid the generation of high voltages in the vicinity of the transmit antenna. While this loop does exhibit a bidirectional pattern, it does not seem to couple to surrounding objects like the K9AY loops do, negatively impacting the pattern. In the shack, a W1VD MF optimized preamp based on the W7IUV design helps bring the receive level up above the internal noise of the receiver. This is a high performance preamp based on the 2N5109 and offers about 20 db of gain and a noise figure of around 2.5. So far I am very pleased.
Interested in getting on 630m now? Its only $65 for a 2 year renewable Part 5 experimental grant! Contact me for details on the very easy and quick online filing process! Most people don't realize just how easy it is!
Using scopematch, I can resonate (X=0 or close to it!) my 630 meter TX antenna by adjusting my remote control variometer so that voltage (top) and current(bottom) are equal phase on the scope (ELI the ICEman is applicable here!) Equal magnitude of the waveforms means that the real part of the impedance is 50 ohms. This concept is applicable for any RF spectrum. Its much better info than an SWR meter and more accurate than most consumer-grade antenna analyzers. Details at http://myweb.tiscali.co.uk/wgtaylor/LFTA.pdf
How I came to be a Ham
As I was first licensed while in high school in the late 80's, I am very fortunate to have learned directly from a large number of very experienced real radio men. I would not trade that experience for anything in the world and most of them are silent keys now and are truly missed. My primary elmer was Jimmy Miles, KA5V (he is still alive, living on the golf course in Gatesville, TX from what I understand). Jimmy was a top of the Honor Roll DXer, complete with well equipped station and tall tower at the highest point in north Texas. He was the perfect radio role model for me. His son was one of my close friends so one day while I was over at their house, I asked about ham radio - I had wanted to be a ham since elementary school when I saw a film strip (remember those?) at school about it. My uncle, an electronics man in the Navy and CBer, encouraged me to do it as well. Within a month I had learned the code at 5 wpm and the Novice test material. Jimmy had gotten another ham, Bill Smith, KO5Y (SK), and we sat at his kitchen table as I took a hand written novice exam. The test was literally written on a lined, "Big Chief" note pad. There were no multiple choice questions - this was all fill in the blank.. I was up to the challenge because I was passionate about what I was doing and being a kid, I knew everything HI! After acing the written test, Jimmy sat me down in front of his TS-840 for the code test. I had to copy the W1AW 5 wpm code practice. I was ready for the test, but I was nervous. Somehow I fought through the test and Jimmy and Bill were satisfied (a lot more to this story to be expanded upon later). I was going to be a ham! I remember the day my novice ticket showed up. I was working as a student intern at the Superconducting Supercollider's forward development complex in Desoto, TX that summer and rushed home daily to check the mail - it took about 6 weeks then! Remember the 1980's movie "A Christmas Story" where Ralphie is waiting on his "Little Orphan Annie" decoder pin to arrive in the mail? It was like that. I opened the envelope from the FCC and was in awe of the official FCC document, complete with smeared carbon imprint from the impact printer. These were not nice laser forms like we have today. These were only a step up from a mimeograph sheet! I actually had a hard time reading my call sign at first but a little effort revealed that I was KB5NJD and I knew I would be for the remainder of my life. I worked phone on 10m and remember my first QSO was KC4ASM in TN. He sent me a QSL card on a 3 X 5 note card as he did not have anything else at the time. I was very appreciative. I also operated 15, 40 and 80m CW because I was preparing for the general code test (13 wpm). I loved 80m Novice CW on a cold winter night using the Swan 500CX. I had been bitten by the DX bug and had also heard the DFW traffic net on the Dallas repeater while listening on my scanner. In fact, hearing that 2m net piqued my curiosity about traffic handling. This was something I wanted to do. After a few months I upgraded to Technician and could check into the traffic net. I learned a lot and it was not too long before I was a net control station. I wanted to be a net liaison for the HF nets but they operated outside of my operating privileges so I started working hard on the general upgrade. Like before, I had no problem passing the theory. And no, I did not memorize the material like so many do today. Those were different times and I was a homebrewer with a lot of positive technical influence surrounding me. I struggled getting over the 10 wpm hump, however, but finally passed the 13 wpm code at a test session at Hardin Electronics in Fort Worth one monday night. That was an interesting test session. There were several of us sitting in the back room waiting to take the code test. I was the youngest followed by 3 or 4 old men. The code test started and I felt like I had solid copy. Judging from what I wrote down, that was the case. I got the test and nothing looked right! I knew I had the right answers! I emphatically raised my hand and said, "uh, this is the wrong test!" The old men and testers kinda laughed and insured me that I was wrong. I emphatically stated again that it was the wrong test and they looked at what I had copied and agreed... The sad part is that one of the guys had already turned in his test. He had guessed on all of the answers and I don't recall if they gave him the chance to try again. I, however, aced the code test and had greatly expanded my privileges. I was very active chasing DX on phone and CW, acting as an NCS station in the local 2m NTS net and functioning as a liaison station on HF for the Texas CW Net and Texas Traffic Net. Being a high school student about the enter college, I have no idea how I had time for all of this! A few months later, I passed the Advanced exam, which I consider to be the hardest of all ham exams. As an avid CW operator and someone with technical experience, I was ready a month later for the Extra exam. The theory was no problem and neither was the code. I sat across from Jim Bellamy, WB5NOF, at the TU Electric building in Duncanville, TX and we copied the 20 wpm test with no problems and we both upgraded to Extra that night. It was the summer of 1990 and was the start of a lifelong adventure. I was an armchair traveler and I was ready to get out of town... There is a LOT more to this story and I hope to chronicle those experiences and adventures going forward. I have written volumes about my personal on-air experiences and hope to some day transcribe those stories for public consumption. Ham radio is more than a hobby. It is a way of life. If you don't understand that, you just have to look harder.
Below is the first tower that I had at my parents house while in high school from which all those great DX adventures occurred. My ham life read like Bob Locher's book, "The Complete DXer". Such great times...
73 and see you in the pile up!!!
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