Hello, my name is Karl, from ‘Pennsylvania Dutch Country’ (which is actually Pennsylvania German, but that’s another story). I have gear for every US ham band from 160 meters through 900 MHz, as well as receive capability below, between, and above these bands. I enjoy DXing and ragchewing on HF SSB, and local VHF/UHF FM operating. I have a special fondness for HF AM (as well as VHF), though I don’t really have a worthy station set up yet. I also like Field Day, but otherwise am not really a contester. I am not a paper chaser; I don’t bother with awards or QSL cards (nor have I gotten into the various implementations of virtual QSL cards). I like CW, and have recently been getting back into the mode after not using it much for a long time. I did quite a bit of packet, RTTY, and AMTOR operating back in the day, but haven’t done much digital since the onset of ‘sound card’ modes (I always liked real data controllers, like a TNC or Kantronics UTU). I have the equipment for such operation (like many other things), just haven’t devoted much time to it. I’ve always really liked shortwave listening, VHF/UHF scanner listening, and some AM/FM/TV DXing here and there. I’ve also played around with weather fax, SSTV, ATV, DRM reception, LF beacon reception, decoding digital voice, and various other bands/modes.
I have recently become quite interested in SOTA (Summits on the Air), a very cool activity involving portable operation from mountaintops. So far I have only activated a few summits, though I have worked over 120 summits as a chaser, and I am hooked! SOTA is also providing the incentive which I have needed to get back into CW.
If you work me on HF or 6 meters, I am probably using my Yaesu FT-450 or FT-817 with HL-45B amplifier into the 80 meter horizontal full-wave loop at the LRTS club site (club call W3AD; more details below under resurgence of interest
). For anyone who cares, this site is just over the line in Lancaster County, a fraction of a mile from Lebanon County, in grid square FN10tf.
Mobile station: Yaesu FT-857D with SGC SG-237 autotuner and 6 foot/1.8 meter whip + Icom IC-2720H with Austin dual-band whip in Jeep Wrangler
Portable gear: Yaesu VX-7, VX-3, FT-817, Alinco DJ-G29T (the VX-7 and FT-817 are easily my two favorite radios EVER!)
I also have numerous other transceivers and receivers; these are the ones I use most often. For whatever reason, I have definitely become a Yaesu fan. Icom and Kenwood (as well as other companies) just don’t have anything interesting to offer at this point.
Outside of radio (is there such a thing?), I worked my way up from being an electronics technician to an embedded hardware and software engineer, having designed industrial control systems for various markets. More recently, all of the ‘opportunities’ I’ve found have turned out to be dead ends. While I look for work, I’ve been developing some amateur radio accessories which I hope to turn into a product line. Of course, investment is at least as hard to find as a decent job…
Other hobbies include geocaching, hiking, off-road driving, listening to EDM (especially trance, house, and techno), rifle and pistol shooting, collecting old computers and calculators, high-end LED flashlights, and using superior/alternative computer hardware and operating systems (ARM processors and Linux for example, such as on the remarkably cool Raspberry Pi). Of course, most of these tie together: I always have an HT along when I’m out in the woods, geocaching has some striking similarities to SOTA, the Jeep has an HF/VHF/UHF setup in it, and my interests in computers and radio both go back as far as I can remember.
Very early on, I recall writing a BASIC program on a TI-99/4A which displayed random data on the screen, and I pretended it was a satellite data downlink. Not many years later, I digipeated packets through the Mir space station and back to myself (for whatever reason, ISS has never intrigued me the way Mir did). I also wrote a BASIC program which turned a Radio Shack Color Computer into a repeater controller, and later a simplex repeater controller. That was while I was still in college, before I even started repairing equipment professionally, let alone designing it. I can’t say that amateur radio caused my interest in and pursuit of the electronics field (though it has certainly been a huge part of it); I’ve always just been into all of the above for as long as I can remember. Keep in mind that the entire field of electronics initially developed as a result of the pursuit of radio.
My amateur radio non-interests would include such things as D-Star, Echolink, and the like. Proprietary codecs, hideous audio quality, lack of interoperability, and dependence upon inferior hardware and operating systems as well as the internet are not hallmarks of real amateur radio. If you want digital audio, get a cell phone (which, at least on a proper GSM network, sounds better than any digital two-way format; CDMA, on the other hand, could give D-Star, DMR, etc. serious competition in the garbled, underwater sound category). If you want to talk to someone on the internet, use a VoIP phone. One significant advantage of amateur radio is its robust simplicity, all of which is thrown out the window when it becomes dependent upon overcomplication and outside networks.
Another annoyance is the proliferation of continuously active repeater link systems which tie up numerous repeater pairs with redundant, overlapping coverage of the same content-free conversations. Bizarrely, some such systems automatically shut down at night; I suppose emergencies only occur during business hours or something. Makes one wonder if such systems have anything to do with fulfilling the mandate of amateur radio or providing any useful service, rather than merely feeding someone’s ego…
SDR definitely has major potential as a way forward, as long as it is implemented properly. Making it dependent upon inferior mass-market hardware and operating systems (Intel processors and Windows for example) is the opposite of a way forward. Besides the stability and reliability issues, I much prefer a radio to look and feel like a radio, not a black box connected to a lowly PC. Computers are useful accessories for radio communications, but I would rather not have a hard drive crash or virus (or myriad other failures) compromise basic radio functionality. Not to mention, waiting for a radio to boot up is simply absurd.
I have mixed feelings about eSSB. Good audio is always a nice change, but it seems somewhat pointless to run massive amounts of audio processing gear on SSB, which doesn’t have a carrier to quiet the noise between speech components the way AM does. Additionally, the excessive bass components which are often present make correctly tuning an SSB signal much more difficult, and can detract from readability depending on conditions. Good quality AM, on the other hand, is one of the most pleasant things I’ve ever experienced on radio.
HOW I GOT STARTED
I was interested in amateur radio for years before I finally got my ham license at age 14. I always knew I was going to become a ham, I just didn’t know when. A local club advertised a Novice class, finally giving me the opportunity to get involved. I upgraded to what was later known as Technician Plus immediately thereafter. I had a lot of fun on 10 meter SSB with a modified Realistic TRC-458 base station CB rig, and 2 meter FM with crystal-controlled radios and then a Ten-Tec 2591 synthesized 2M HT (one of the worst transceivers I have ever used!). Unlike some people, I will also admit that I was pretty heavily involved in 11 meter CB operation around that time, and had a lot of fun with that as well. That band, despite its obvious shortcomings, is still somewhat nostalgic to me.
About 5 years later, while in college, a member of the club in that town offered study sessions for the General class upgrade. I attended those, and did lots of CW practice on 10 meters with another local ham, getting to where I could copy 15 WPM pretty solidly. I went to a VE test at a hamfest, and jumped from Tech Plus to Advanced. I passed the Extra theory as well, but never got my CW speed up to 20 WPM. It took about another 15 years until I finally got around to the Extra upgrade. My call is still my original Novice call sign.
RESURGENCE OF INTEREST
I’ve gone through various phases and levels of activity, though I have always made a point of having an HT with me and mobile VHF/UHF radios in my vehicles even when I wasn’t particularly active. More recently, I have also had an HF mobile setup, though I haven’t done much operating other than local VHF/UHF activity. We’ve also had a decent setup at our radio club site on a local mountain (W3AD
, the Lancaster Radio Transmitting Society, http://www.lrts.org/
), but I hadn’t done much operating overall from there for years either.
That all began to change during the winter of 2012/2013. N3TUQ and I started to discuss what we could potentially do to improve the HF station at said club site. We had been using a 75 meter dipole fed with ladder line, along with an LDG autotuner and balun. It worked reasonably well on most HF bands, but it had trouble tuning up on some bands, it received a lot of noise, and it created RFI problems. We wondered what more might be possible.
We came up with the idea of a rectangular horizontal loop, approximately a full wavelength long on 75 meters. We figured out that we could install it in a slightly different location than that of the dipole. We hoped that this would cut down on noise and RFI issues, as it would be farther from the power lines, towers, guy wires, main operating building, and the equipment shelter containing repeaters and other equipment.
Some research turned up CNC machined Delrin insulators called Ladder Snaps, which would allow us to construct open-wire feedline from 14 AWG wire, which should outperform the ladder line. We also decided to use proper antenna wire and rope from DX Engineering. The plan was hatched, parts were ordered, and then we waited for decent weather. Even before it arrived, some of the undesired trees and brush which had overgrown the area where we wanted to place the loop began to be cleared.
MAKING IT HAPPEN
The following spring, we assembled a group and got to work. Before long, we had the envisioned loop constructed and installed at roughly 20-25 feet/7 meters. One intriguing characteristic was made possible by a special Delrin insulator from the same supplier as the Ladder Snaps: the entire antenna and feedline are constructed from a single, contiguous piece of wire. There are no joints or splices anywhere. The new open-wire line is suspended by ropes, keeping it away from all metal and other objects from the feedpoint all the way to the operating building. Inside, it connects to the balun, and from there about one foot of Teflon coax leads to the tuner, minimizing loss in that critical (and often overlooked) area. We also put extensive effort into cleaning up other potential noise sources at the site. Most of the computer networking hardware has been moved into the shelter with the repeaters. Most switching power supplies have been eliminated, with much of the site running from several banks of 12 volt batteries (which also back up the repeaters), with a single large switching supply (with an added EMI filter) inside the shelter to charge them.
The results of this effort have been nothing less than spectacular. I have operated HF from this site on many weekends since installing the loop, and not even trying terribly hard, I have already worked all 50 US states and over 150 DXCC entities. All of these contacts were made with no more than 100 watts (many from my FT-450), while some were made with just 5 watts from my FT-817, and others with an HL-45B amp boosting it to 50 watts. It has become common to break through pileups, and I have received many reports like ‘big signal’. The elevation of this site (roughly 1170 feet/356 meters above sea level) certainly helps, but the antenna still outperforms anything else we have ever tried up here. It tunes up more easily and consistently on virtually every band from 160 through 6 meters than the old dipole ever did. It also does not appear to have any significant directional characteristics, as I have worked DX all over the globe. At one point, I was told that I had the strongest signal on the entire 20 meter band by a European station with an SDR display. Perhaps even more amazing is the fact that I have worked Europe on 75 meter SSB with no trouble in August and September. I never dreamed that such was possible without transmitting 1500 watts into phased arrays or Yagis and receiving on Beverages. More recently, winter conditions actually let me work Europe on 75 meter SSB with 5 watts from an FT-817!
The loop is amazingly quiet on receive. 20 meters in the summer (barring something like a thunderstorm or power line noise) often has an S0 background noise level. I’ve simply never experienced anything like this; that’s likely why I have done more HF operating in the last several years than I probably did total in the previous 25 years. That activity level is also what prompted me to update this page, as people are actually looking me up here now. 😉
MAJOR RFI DISCOVERY
I made an interesting discovery as a result of trying to minimize the receive noise at this site. We used to take it for granted that there was simply a lot of noise everywhere, as there were so many switching power supplies strewn about and so on. We figured that’s just how it was, and we had to live with it. Now, the bands were actually quiet for the most part. However, there were still certain frequencies where significant noise spikes were present. One in particular got my attention, and became the focal point of my investigation: a strong, rough carrier near 14.273 MHz. Tuning around, I noticed similar signals on other frequencies. I found a pattern: they occurred at regular intervals of approximately 61.06 kHz. I started calculating and tuning in other multiples, and soon realized that the same signals recurred across much of the HF spectrum.
TRACKING IT DOWN
Listening on a handheld receiver and shutting down every possible source of RFI in the entire site did not eliminate the signals. We determined that some of them were actually coming from a neighboring site used by another amateur club. After much research and experimentation, I finally found the source of the signals: 100BASE-TX, otherwise known as 100 megabit wired Ethernet networking. Not any particular device, but the standard itself. I found a spectrum graph of a 100BASE-TX transmitter, and it shows broadband noise from the bottom of HF through at least 150 MHz, with the strongest peak around 15 MHz. No wonder I first found it on 20 meters! I now also know the mechanism by which it radiates: the use of unshielded Ethernet cable of any grade lower than good Category 6. Cat 5 or 5e cable is not sufficiently well balanced to contain these signals, and by its very nature performs a differential to common mode conversion.
I have since confirmed this in numerous installations, both commercial and residential, with a very simple (in retrospect) technique. Take a handheld radio with HF receive coverage and a VHF/UHF rubber duck antenna, and tune it to 14.275 MHz AM (I typically use a Yaesu VX-3 and a Maldol Active Hunter antenna; any similar setup should provide similar results). It may be necessary to open the squelch on the radio. Hold the antenna next to an Ethernet cable with an active 100 Mbps connection on it, and there is virtually guaranteed to be a strong signal present. Move the antenna along (and perpendicular to) the cable slowly, and the signal will increase and decrease in strength several times per inch of cable. This is literally a result of each individual twist in the twisted pair converting some of the differential signal into common mode radiation. The worst offenders can be heard for some distance away from the cable, even with such an intentionally insensitive receive setup. Note that shielded Cat 5 or 5e (if properly terminated), as well as quality unshielded Cat 6, do not generate nearly as much interference. This also totally explains the various reports I’ve heard over the years of ‘wireless routers interfering with 2 meter HTs’ and such. It has nothing to do with the wireless aspect; a wired 10/100 switch does exactly the same thing. It should also be noted that I tried extensive experiments with ferrite cores and grounding; no combination of the above (not even 8 cores on a single 6 foot patch cable) made any significant difference in the radiation from the cable. Think of the cable as being similar to the leaky coax which is often used to radiate signals along its length intentionally inside tunnels and similar settings.
I conclude from my research and experience that unshielded Cat 5 or Cat 5e should absolutely never be used for anything higher than 10 Mbps Ethernet, especially in an environment where any type of HF or VHF receiver will be used. Note that gigabit Ethernet generates a similar overall spectral profile, though with different modulation characteristics; it appears to generate more of a broadband hash than discrete carriers, but still causes interference.
I recently discovered that even some unshielded Cat 6 cable is capable of radiating considerable RFI. As already dictated by common sense anyway, shielded cable is simply the only way to go to assure a clean installation.
Further research has revealed the origin of the 61 kHz spacing between the RFI carriers. 100BASE-TX uses a 125 MHz clock, which is divided by 2047 in a scrambling circuit. This is intended, ironically enough, to reduce EMI by spreading the signal across a wide portion of the spectrum, rather than generating very strong peaks at frequencies such as 31.25 MHz (125 MHz / 4) which would otherwise be generated by the MLT-3 coding scheme used. 125 MHz / 2047 = ~61.064973 kHz, which totally explains the spacing of the offending signals.
Additionally, I have found similar carriers offset by 1/2 of the expected 61.06 kHz spacing in certain portions of the spectrum. This appears to be particularly pronounced in the upper HF and VHF region.
I have written eHam reviews of various radios and accessories. Here are direct links to some of my favorites:
I’ve also written reviews for various microphones, older HTs (Yaesu VX-5 and Standard C558A), the SGC SG-237 tuner, and others. Stay tuned for more as time permits.
This is a work in progress, and will be updated as I have the opportunity. I plan to add pictures, and possibly move some of the content to my own web page; I just wanted to put the info out there in some form as a starting point. Hopefully someone finds some of this to be interesting and/or beneficial.