Posts Tagged ‘amateur’

Just Get On The Air! (A Makeshift Temporary Dipole Shortwave Antenna)

It might not take as much antenna as you may think would be necessary to make two-way contacts on shortwave radio (as an amateur radio operator putting an HF transceiver on the air). However, often, makeshift antennae are effective enough to be viable–just look at all the contacts many amateur radio operators make with their low-power (QRP) rigs (transceivers) using short, helically-wound, mobile antenna sticks. If they can work magic with such inefficient antenna setups, surely your effort at an antenna would pay off to some degree. Right?

Of course, I want to make a proper dipole out of this example antenna. But, while I wait for the rest of the parts I need to complete this antenna project (pulleys and a ladder, and maybe a potato launcher), I’ve put this makeshift antenna on the air, with it just high enough so that I can enjoy some time on the shortwave bands.

With this antenna, I’ve made successful two-way voice and Morse code contacts (QSOs) with stations in Europe and across North America. I am able to tune it on the 60-, 40-, 30-, 20-, 15-, 17-, 12-, and 10-Meter bands. Reverse beacon detection picks up my Morse-code CW signals, especially on 40 meters (the band on which it is tuned physically).

The bottom line: just get something up in the air and start communicating. Improve things over time. You’ll have much fun that way.

73 de NW7US dit dit

Software-Defined Radio: Try Before You Buy? You Might Like It!

Sure! You don’t need to have a software-defined radio (SDR) before you start learning how to use the technology; there are a few different paths you can take, exploring and learning about SDR.

One way to gain some experience with SDR without spending a dime is to install a free software package for the very popular, non-Linux, operating system (that starts with ‘W’), and give SDR a test drive. If you like it, you might consider getting your own hardware (like the SDRplay RSPdx, for instance), and connecting it up to your computer and running this software, too.

Why I Dived Into SDR

I have always loved radio, ever since the early 1970s, when I discovered shortwave radio. In the last couple of years, I’ve had an increasing interest in the world of SDR. When I am working, but away from home (remember those days, before Covid?), I want to sample news and programming from around the world, but through shortwave. The way to do that, I found, is by using the various SDR options which allow a person to tune a remote receiver, and listen.

I also find working with the waterfall of a typical SDR-software user interface rewarding because, instead of blindly searching for signals in a subband, I can see all of the received signals on the scrolling time representation of a slice of frequency. Simply select that signal on the waterfall, and the radio tunes right to it.

I often connect to different SDR radios around the world, to catch all manner of shortwave signals, from maritime, military air, trans-oceanic air, or coast guard radio traffic, or other interesting HF communications including amateur radio CW and SSB signals. Occasionally, I also check out VHF and UHF signals from around the world. All of that, while instead an office building that is not suited for shortwave radio reception.

I’ve now decided to give back to the community; I’ve added my SDR receiver to the collection of receivers located around the world on the SDRSpace network of SDR radios.

My new SDRplay RSPdx software-defined radio receiver is live, via, using the SDR Console software (Version 3).

The receivers are online whenever I am not transmitting and when there are no local thunderstorms.

Antenna Port A is connected to a wire antenna (a horizontal 100-foot wire that runs out from my house’s chimney to a tall tree; about 10 feet of that wire is oriented vertically, where the wire passes through a pulley and then is weighted down so it can move with wind-driven tree movement), while Antenna Port B is connected up to a VHF/UHF discone.

Both antenna systems have an AM Broadcast band notch (reject) filter reducing local AM Broadcast-Band radio station signals by about 30 to 40 dB. I need to use these because the very close KLIN transmitting tower is just miles away and those signals overwhelm the receiver. When I use the signal filters, the local AM Broadcasting signals no longer overwhelm the receiver.

In the following video, I first explain my SDR setup, and in the second half of the video, I tune around the radio spectrum, using the software to control my SDR receiver.

A Couple of Questions

After watching this video, WO9B wrote an email to me. Michael asked of me two questions, summed up as:

1. Your SDR window has the IF screen on top. How is that accomplished?

2. Your AM Broadcast filters; more info, please. I live in the area of mucho broadcast stations and that looks like something I could use.

In the following video, I demonstrate how I changed my layout of the SDR Console software. And, I mention the AM Broadcast Filter for SDR Receivers (the hardware filter is found here:

To Use My Receiver

Download the latest version of SDR-Console from – there is a 32-bit and a 64-bit Windows installation package.

The 64-bit installation package may be downloaded from one of these three sources:

1. Google
2. DropBox
3. Microsoft!AovWaZDu7Hrd3U-yqK1bs3wuaFw2?e=o4nKeh

The 32-bit installation package can be downloaded from one of these three sources:

1. Google
2. DropBox
3. Microsoft!AovWaZDu7Hrd3U4mJiiRtI9lm70s?e=HDG4ZX

Install the SDR Console package according to the directions given. Once you have the software installed, you will want to add my server. It takes some work to get familiar with the software, but there are online FAQs on how to begin.

One guide on how to add a server to the list from which you can pick may be found, here:

I worked on getting all of the bugs worked out of my installation before making the video. It did take some work, and reading up on things. But, the software is solid and a good contender against SDRuno, and HDSDR, and, this way I can share it online with you.

My server is known as, ‘0 NW7US‘ — it will be online when I am not using my antenna systems for transmitting. It will be offline during thunderstorms, or during times when I must use the systems for transmitting.

Look for the 0 NW7US server.

Software-defined radio is a great way to hear all sorts of communications, from local AM broadcast stations, FM stations, VHF Air Traffic, to shortwave radio stations including amateur radio HF communications.

Thank you for watching, commenting, and most of all, for subscribing; please subscribe to my YouTube Channel: Also, please click on the bell, to enable alerts so that when I post a new video, you will be notified. By subscribing, you will be kept in the loop for new videos and more.

73 de NW7US

.. (yes, this is an expansion of an earlier post… forgive the redundancy… thank you) ..

Check Out My New SDRplay RSPdx Software-Defined Radio Receiver – Live!

My new SDRplay RSPdx software-defined radio receiver is live, via, using the SDR Console software (Version 3).

The receivers are online whenever I am not transmitting and when there are no local thunderstorms.

Antenna Port A is a wire antenna (100′), while Antenna Port B is a VHF/UHF discone. Both have an AM Broadcast band reject filter, reducing local AM Broadcast signals by about 30 to 40 dB. I need to use these because the very close KLIN transmitting tower is just miles away and those signals overwhelm the receiver. When I use the signal filters, the local AM Broadcasting signals no longer overwhelm the receiver.

Let me know what you think. Enjoy!

To use my receiver:

Install the latest version of SDR-Console which can be downloaded from

Install SDR Console according to the directions given. Once you have the software installed, you will want to add my server.

It takes a little to get familiar with the software, but there are online FAQs on how to begin.

My server is known as, ‘0 NW7US‘ — it will be online when I am not using my antenna systems for transmitting. It will be offline during thunderstorms, or during times when I must use the systems for transmitting.

Software-defined radio is a great way to hear all sorts of communications, from local AM broadcast stations, FM stations, VHF Air Traffic, to shortwave radio stations including amateur radio HF communications.

Thank you for watching, commenting, and most of all, for subscribing; please subscribe to my YouTube Channel: Also, please click on the bell, to enable alerts so that when I post a new video, you will be notified. By subscribing, you will be kept in the loop for new videos and more.




From Lightning Comes a New Icom IC-7610 (First Transmission)

Wow. What a radio!

One of the most useful (and, to me, amazing) features of this Icom IC-7610, is the IP+ function, which, when turned on, improves the Intermodulation Distortion (IMD) quality by optimizing the direct sampling system performance. This function optimizes the Analog/Digital Converter(ADC) against distortion when you receive a strong input signal. It also improves the Third-order Intercept Point (IP3) while minimizing the reduction of the receiver sensitivity.

In short: I was listening to an s-0 (i.e., no strength-meter movement) weak signal of a DX station, when right adjacent to the frequency came an s-7 signal, wiping out my ability to copy that weak signal. I turned on the IP+ and the distortion of the adjacent signal disappeared, and once again, I heard the weak signal IN THE CLEAR! WOW!

This video is a quick capture of my running the Olivia Digital Mode on HF, on the 30-Meter band. The transmissions are of a two-way Olivia digital-mode radio conversation between station K8CJM and station NW7US on 12 November 2019 (UTC date). K8CJM is located in Dayton, Ohio, and I am located in Lincoln, Nebraska. I’m running the radio at full power. The radio is rated as being able to handle 100% duty cycle at full power. The radio ran cool, no significant heating.

A few months ago, a lightning strike took out my ham radio station. The antenna was NOT connected, but I did not unplug the power supply chain and my computer from the wall. The surge came in through the power mains, and fried my uninterruptable power supply, the interfaces between my PC and radio, and fried the radio. Thankfully, all of that was covered by my homeowner’s insurance policy, less the steep deductible. My insurance covered all of the blown items, and that provided me this chance to obtain a repack version of the Icom IC-7610. I bought an extended four-year warranty.

CAUTION: Check the documentation of your transceiver/transmitter. NEVER run your radio’s power out at a level that exceeds what it can handle in reference to the duty cycle of the mode you are using. Olivia, for instance, is a 100-percent duty cycle mode. Morse code is NOT quite 100% duty cycle. Nor is SSB, a mode that operates with a duty cycle much lower than 100%. Your radio’s manual should tell you the specifications regarding the duty cycle it can handle! If you run more power than your radio can handle with the given duty cycle of the mode in use, you will blow your radio’s finals or in some other way damage the radio! Beware! I’ve warned you!

Compression and ALC!?

Some have noted that it appears that I’ve left on the Compression of the transmitted audio. However, the truth is that compression was not being used (as is proof by carefully taking note of the zero meter movement of the Compression activity). I had the radio set for 20-Meter USB operation on the Sub VFO. Compression was set for standard USB operation. Note also that the radio was transmitting USB-D1, which means the first data/soundcard input to the radio.

Also, some people complain about my use of ALC, because, in their view, ALC (automatic level control) is a no-no for data modes.

The notion that one must NEVER use ALC when transmitting digital modes is not accurate.

Multi-frequency shift keyed (MFSK) modes with low symbol rate–such as the Olivia digital modes–use a single carrier of constant amplitude, which is stepped (between 4, 8, 16 or 32 tone frequencies respectively) in a constant phase manner. As a result, no unwanted sidebands are generated, and no special amplifier (including a transmitter’s final stage) linearity requirements are necessary.

Whether the use of ALC matters or not depends on the transmitted digital mode.

For example, FSK (Frequency-Shift Keying; i.e., RTTY) is a constant-amplitude mode (frequency shift only). In such a case, the use of ALC will NOT distort the signal waveform.

PSK31 does contain amplitude shifts, as an example, therefore you don’t want any ALC action that could result in distortion of the amplitude changes in the waveform.

On the other hand, the WSJT manual says that its output is a constant-amplitude signal, meaning that good linearity is not necessary. In that case, the use of ALC will NOT distort the transmitted signal-amplitude waveform. You can use ALC or not, as you choose when you run WSJT modes, or Olivia (MFSK).


Nowhere in this am I advocating running your audio really high, thinking that the ALC will take care of it. I am not saying that. I am saying that some ALC is not going to be an issue. You MUST not overdrive any part of the audio chain going into the transmitter!

Transmit audio out of the sound card remains at a constant amplitude, so there will be no significant change in power output if you adjust your input into the radio so that the ALC just stops moving the meter, or, you can have some ALC meter movement. You can adjust your audio to the transmitter either way.

If the transmitter filters have a significant degree of ripple in the passband then you may find that RF power output changes with the selected frequency in the waterfall when there is no ALC action. Allowing some ALC action can permit the ALC to act as an automatic gain adjustment to keep the output power level as you change frequencies.

Linear and Non-Linear

Regarding linear and non-linear operation (amplifiers, final stages): While a Class-C amplifier circuit has far higher efficiency than a linear circuit, a Class-C amplifier is not linear and is only suitable for the amplification of constant-envelope signals. Such signals include FM, FSK, MFSK, and CW (Morse code).

If Joe Taylor’s various modes (in WSJT software) are constant-envelope signals, than class-C works, right? At least, in theory.

Some Additional Cool History

The digital mode, Thor, came out of DominoEX when FEC was added. Here is an interesting history of FSQ that seems to confirm that FSQ is like MFSK, so no problem with a bit of ALC.

The following is from

History – Let’s review the general history of Amateur MFSK modes. The first Amateur MFSK mode developed anywhere was MFSK16, specified by Murray Greenman ZL1BPU, then first developed and coded by Nino Porcino IZ8BLY in 1999. Before MFSK16 arrived, long-distance (DX) QSOs using digital modes were very unreliable: reliant, as they were, on RTTY and later PSK31. MFSK16 changed all that, using 16 tones and strong error correction. Great for long path DX, but nobody could ever say it was easy to use, never mind slick (quick and agile)!

Over the next few years, many MFSK modes appeared, in fact too many! Most of these were aimed at improving performance on bands with QRM. Most used very strong error correction, some types a poor match for MFSK, and these were very clumsy in QSO, because of long delays.

The next major development, aimed at easy QSOs with a slick turnaround, was DominoEX, designed by Murray Greenman ZL1BPU and coded by Con Wassilieff ZL2AFP, which was released in 2009. Rather than using error correction as a brute-force approach, DominoEX was based on sound research and achieved its performance through carefully crafted modulation techniques that required no error correction. The result was a simpler, easier to tune, easily identified mode with a fast turn-around.

DominoEX is widely used and available in many software packages. A later development by Patrick F6CTE and then Dave W1HKJ added FEC to this mode (THOR) but did not add greatly to performance, and at the same time eroded the fast turn-around. The final DominoEX- related development was EXChat, a version of DominoEX designed specifically for text-message style chatting. While completely compatible with DominoEx, it operates in ‘Sentence Mode’, sending each short over when the operator presses ENTER. EXChat was developed by Con ZL2AFP and released in 2014.

Back in 2013, Con ZL2AFP developed an MFSK mode for LF and MF which used an unusual decoding method pioneered by Alberto I2PHD: a ‘syncless’ decoder, which used a voting system to decide when one tone finished and another began. The first use of this idea was in JASON (2002), which proved to be very sensitive, but very slow, partly because it was based on the ASCII alphabet. The new mode, WSQ2 (Weak Signal QSO, 2 baud) combined the syncless decoder with more tones, 33 in total, and an alphabet specially developed by Murray ZL1BPU, which could send each lower case letter (and common punctuation) in just one symbol, resulting in a very sensitive (-30 dB SNR) mode with a 5 WPM typing speed.

In the subsequent discussion in late 2014, between the developers ZL2AFP and ZL1BPU, it was realized that if the computer had enough processing power to handle it, WSQ2 could be ‘sped up’ to become a useful HF chat mode. This required a large amount of development and retuning of the software to achieve adequate speed was involved, along with much ionospheric simulator and on-air testing used to select the most appropriate parameters.

Tests proved that the idea not only worked well, but it also had marked advantages over existing HF MFSK modes, even DominoEX. As expected, the new mode was found to have superior tolerance of signal timing variation, typically caused by multi-path reception, and would also receive with no change of settings over a wide range of signaling speeds.

So this is how FSQ came about. It uses the highly efficient WSQ character alphabet, IFK+ coding, the same number of tones as WSQ (33), but runs a whole lot faster, up to 60 WPM, and uses different tone spacing. The symbol rate (signaling speed) is modest (six tones per second or less), but each individual tone transmitted carries a surprising amount of information, resulting in a high text transmission speed. And it operates in ‘Chat’ (sentence) mode, which allows the user to type as fast as possible since they type only while receiving.

The ability to send messages and commands selectively has opened a huge array of communications possibilities.

What Makes FSQ Different

Incremental Keying – FSQ uses Offset Incremental Frequency Keying (IFK+), a type of differential Multi-Frequency Shift Keying (MFSK) with properties that make it moderately drift-proof and easy to tune. IFK+ also has excellent tolerance of multi-path reception.

IFK was developed by Steve Olney VK2XV. IFK+ (with code rotation) was proposed by Murray Greenman ZL1BPU and first used in DominoEX. IFK+ prevents repeated same tones without complex coding and provides improved rejection of propagation-related inter-symbol interference. In the context of sync-less decoding, the IFK+ code rotation also prevents repeated identical tones, which could not have been detected by this method.

Efficient Alphabet – In FSQ, a relatively high typing speed at a modest baud rate comes about because the alphabet coding is very efficient. All lower case letters and the most common punctuation can be sent in just one symbol and all other characters (the total alphabet contains 104 characters) in just two symbols. (The alphabet is listed below). This is a simple example of a Varicode, where it takes less time to send the more common characters. The character rate is close to six per second (60 WPM), the same as RTTY, but at only 1/8th of the baud rate. (RTTY has only one bit of information per symbol, 7.5 symbols per character, and wastes a third of its information on synchronization, and despite this, works poorly on HF).

No Sync – Another important factor in the design of FSQ is that no synchronizing process is required to locate and decode the received characters. Lack of sync means that reception is much less influenced by propagation timing changes that affect almost all other modes since timing is quite unimportant to FSQ; it almost completely eliminates impulse noise disruption, and it also contributes to very fast acquisition of the signal (decoding reliably within one symbol of the start of reception). Fast acquisition removes the need for the addition of extra idle characters at the start of transmission, and this leads to a very slick system. Add high resistance to QRM and QRN, thanks to the low baud rate, and you have a system so robust that it does not need error correction.


See you on the bands!

How I Reunited Two Devils Brigade Canadian and American Veterans of World War Two

In the 1990s while living in eastern Montana, I had the amazing experience of reuniting two soldiers that served in the Devil’s Brigade. They both trained near Helena, Montana.

One day, I was operating on the amateur radio shortwave Ten-Meter band, and a gentleman answered my, “CQ, CQ, CQ, this is N7PMS in Montana, Over”. I took notes of our conversation.

The next day, when again I called for any station to answer my call for a conversation, another fellow, from Canada, answered me. I learned something amazing: Both of these two men mentioned that, during World War Two, they both were in the same special forces unit, training near Helena, Montana.

One of these Veterans served in the Canadian Armed Forces, and the other in the American Armed Forces. Listen to my story, for the full details of this amazing experience I had as an amateur radio operator.

Jump to 3:22 if you wish to skip my introduction to the story, during which I give some background on when and so on:

This certainly was one of the most memorable moments in my amateur radio hobby experience! The joy of reuniting friends is good.


The 1st Special Service Force (also called The Devil’s Brigade, The Black Devils, The Black Devils’ Brigade, and Freddie’s Freighters), was an elite American-Canadian commando unit in World War II, under command of the United States Fifth Army. The unit was organized in 1942 and trained at Fort William Henry Harrison near Helena, Montana in the United States. The Force served in the Aleutian Islands, and fought in Italy, and southern France before being disbanded in December 1944.

The modern American and Canadian special operations forces trace their heritage to this unit. In 2013, the United States Congress passed a bill to award the 1st Special Service Force the Congressional Gold Medal.

Thank you for watching, and sharing. Comments are welcome: do you have a memorable moment in your radio hobby experience on the air?

73 de NW7US

My Rebuttal Regarding the Petition by ARRL to the FCC to Expand Technician-Class Privileges

This is my reply to many responses that I have been receiving on my original blog entry, located at this website,(my shortened URL: as well as to the original video, posted in that blog entry.

I wish to reply to all of those who are against the idea of expanding the privileges of the Technician-class licensee, the expansions including the ability to operate Voice and Digital in limited slices in a subset of lower-than-Ten-Meter amateur radio shortwave allocations.

It seems to me, that…

…the issue is not one of Technician-class licensees wanting more privileges, as a whole. What the ARRL is addressing is the *lack* of desire by most current Techs to upgrade.

The logic behind the idea of expanding privileges concludes that if you give them a taste of lower-shortwave propagation and excitement (by moving past the CW-only restriction on the lower tech allocations), then they *will* want to upgrade.

This logic is already proven as applicable by the fact that the General class exists! All that this proposal will do is allow the Tech to experience what could be very attractive–just like for the General.  If it worked in the past with Novice, Technician, General, Advanced, and Amateur Extra (exposing to all of HF, even if by way of a CW-only requirement), then it will work, now.  The difference is that the CW-only requirement on lower HF bands is highly restrictive because the mode is no longer needed to operate on any frequency, and, most will not take the time to learn it just to see if they WANT to explore the lower HF bands, or ever upgrade.

The bottom line is that we should make the Tech ticket more relevant. The expansion is not dumbing down, nor does it give away the farm.

I discuss this original point in the two videos that were lower down in the original post:


Thanks for reading, watching the videos, and having a useful dialog about this very important change to the amateur radio regulations in the USA.


That aside: This may, in the long term, reveal one of two possible truths:

1. There is no real need for three license classes. Two would suffice. General and Amateur Extra, or Technician (merged with General) and Amateur Extra.

2. There is no real need for three license classes. One would suffice. Make the test hard enough to cover the Extra-class material, and all material under that class, and merge everyone into one tested class. I believe that this has been tried in other countries, and it appears to work well.

I’ll be crucified for stating those ideas, but, hey, this is just a hobby.

73 de NW7US dit dit

Short Demonstration of Using Ham Radio Deluxe with WSJT-X and FT8 Digital Mode

Ham Radio Deluxe can log your WSJT-X FT8, JT65A, and JT9 QSOs, via the JT-Alert software. This is a demonstration of my use of HRD and Logbook, during an FT8 QSO,today.

As some of you know, I have had some differences of opinion regarding the selection of frequencies chosen by the FT8 creators and advocates. Regardless, I do still use the mode. Here is proof:

Go ahead and share, if you would. And, please subscribe to my YouTube channel, as I will be creating many how-to videos in the near future.

Thanks and 73 … de NW7US

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