Posts Tagged ‘WSPR’

Power regulator works as polarity protection

Step-down converter based on LM2596. Note the damaged chip

Ok, now I’ve done the test. My QRPLabs U3S runs off a 12 Volt power supply. There are two step-down converters, one for 5 Volts for the processor and another adjustable one for the power amplifier, if one can call 0.2-0.5 Watts a power amplifier. See picture of these voltage converters in this post.

I happened to make a new cable for 12 Volts which had the polarities inverted – and puff – there was a noise and absolutely no response from the U3S. I feared that I had blown the entire circuit. As my power amplifier was turned off, only the 5 Volts supply was affected and upon inspection I found that the voltage converter had a destroyed chip.

Since since they are so cheap, I had a spare. Luckily for me, the U3S worked as it should after replacement. So the LM2596 can take a reversed polarity and sacrifices itself in order to protect the rest of the electronics. Nice!

This post first appeared on the LA3ZA Radio & Electronics blog.

QRSS experiments: FSKCW and Slow Hell

These last few days I’ve been experimenting with my QRPLabs Ultimate 2 and Ultimate 3s transmitting on 7 MHz. In addition to WSPR, the modes transmitted have been FSKCW with 6 second long dots, and Slow Hell with 17 second long characters. The result as received this morning can be seen on the display from the grabber of Les, G3VYZ in Northumberland, UK. This is a stack of 6 consecutive 10 second frames as can be found on the QRSS grabber site of AJ4VD.

FSKCW and Slow Hell reception of LA3ZA at G3VYZ

My signal is on 7,039.870 kHz and has been set up with a FSK shift of 6 Hz. Power output was 0.2 W and the distance is about 890 km.

It works but the reception is much less reliable than for WSPR, which is not so unexpected. At the same time the WSPR signal was received all around Northern Europe (G, GM, DL, OON, OE, LX, LA, OY, OH, PA, SM) as well as on the Canary Islands, 3930 km away.

LF Tests From WH2NXD / NI7J


For those of you with an interest in amateur LF work, you may be interested in the upcoming WSPR test  transmissions from Ron, WH2XND / NI7J, located in Phoenix, Arizona.


One of Ron's several experimental licences allows him to run as much as 10W ERP from 68-76 KHz. To generate this amount of ERP at 75 KHz requires a lot of power and I suspect that he will still be well under his licence limitations ... amateur-sized antennas are just not very efficient on these low fequencies.

Previous experiments a few years ago, at lower ERP, produced impressive results, as shown by one of the WSPRnet maps for an overnight session on 75.075 KHz.


Ron used one of the Hans Summers U3S transmitters to generate his LF WSPR signal, amplifying it with a 400W Hafler audio amplifier. This winter's tests will be at 800W, with a W1VD FET amplifier designed for VLF.

Ron's experimental licence also covers 470 - 495 KHz at a whopping 100W ERP and 130 - 140 KHz at 50W ERP ... some serious power.

You may also find Ron's interesting and well-illustrated website description of some experimental antenna work that he has been doing on MF, LF and what it takes to resonate a typical Marconi 'T' on these bands.

MF- LF 'T' Antenna At WH2XND


75 KHz Loading Coils!

Ron has tentatively chosen late November or early December for his 'almost' VLF tests and when the date and frequency are finalized, I will post the information here on the blog.

Getting Started On The New LF and MF Bands

Finally the long wait is over! The LF 2200m band and the MF 630m band have finally arrived for amateurs in the USA! I'm sure most of you have read the fine print regarding deployment of the two bands, but if not, here is the ARRL's recent announcement.

It has been a very long wait for the FCC to implement these bands after they were approved for amateur use in 2007 and 2012 at the World Radiocommunication Conferences in Geneva. Canadian amateurs have had 630m since 2014 and 2200m since 2009 ... in the meantime, we have been anxiously awaiting the arrival of American amateurs to liven things up and to garner new interest in these bands.

Before operating on these bands, amateurs in the USA are required to register their intent via a simple web form found here on the Utilities Technology Council's website. Then follows a 30 day waiting period during which the UTC will check out your location to be sure that you are not located within 1km of any power lines that might be carrying LF or MF PLC (Power Line Carrier) control signals. If you hear nothing back from UTC within 30 days, you are good to go.

A positive outcome of registering via the UTC form is that there can be no PLC signals implemented on the lines near you at a later date! By registering your intended operating location(s), you are locking-in these spots for no further PLC development. If you have an EOC or Field Day site that you think you may want to operate from at some point, register these as well.

I think it is important that even if you do not intend to operate on either of these bands or perhaps a few years down the road, that you register as soon as possible ... the fewer PLC signals operating close to or within the amateur radio spectrum, the better, and this is one way of furthering that goal.

There has already been a vast amount of published information on both of these bands, describing transmitters, receiving systems and transmitting antennas so I won't go into much detail here regarding these topics ... and besides, it's always very interesting to search these things out yourself, learning as you go. Be assured that either of these bands will present interesting new challenges not encountered in typical HF operation, but all of the basic principles you are used to still apply ... it's just that things are much bigger down below the broadcast band!

Far and away, the best source of information for US amateurs can be found on John Langridge's (KB5NJD) NJDTechnolgies website. John has been operating on MF for several years already with an experimental licence (WG2XIQ) and is more than an expert on this topic.

His daily blog includes a detailed account of worldwide activity on 630m and makes for fascinating reading. His website provides all of the information and valuable links that you might need to plan your own LF or MF station. The information on his site, if printed out, would make a wonderful LF / MF Handbook!

My own blog and website also contain much helpful material, with a particular emphasis on Canadian activity on these bands. All of my blogspots dealing with 630m can be found here and contain enough bedtime reading to keep you busy for many nights.

If you are thinking of getting on either of these new bands, particularly 630m, here is a short Q & A that may help you through the initial planning stage of  how to get started.

What modes are commonly used on these bands?

At present, due to the low level of two-way amateur radio activity, the WSPR mode has been dominant. This is a weak-signal 'beacon-only' mode so most two-way contacts take place either on CW or on the weak signal JT-9 mode. JT-9 has been specifically designed for HF and LF / MF weak signal two-way work and can dig as deep as -27db into the noise to provide a contact that could never be completed on other conventional modes such as CW.

With the influx of new activity on these bands, particularly on 630m, I expect that most two-way work will equal or surpass the amount of WSPR activity and that JT-9 and CW will do most of the heavy-lifting.

How far can I work on these bands?

Although the erp limits appear to be QRP-sized, this is somewhat misleading ... it is astonishing what can be done. Don't think that '5W eirp' means that you can only run a transmitter capable of generating 5W. Because antennas are so inefficient on these bands, it is often necessary to run several hundreds of watts in order to achieve the legal eirp limits. The bigger and more efficient your antenna, the lower the power needed becomes. On many nights, 5W eirp will get you clear across the country on MF.

However, if you build something for 630m that only produces 25W of power, you will still have the capability of working many stations in other states on most winter evenings or mornings, as propagation, the 'great equalizer', can be amazing at times.

Presently, most stations operating on WSPR will often be detected from one coast to the other and those with excellent locations near the coast will soon be working stations down under or in Europe, either on CW or on JT-9. If you can, design and build for the maximum eirp, 1W on 2200m and 5W on 630m.

What type of transmitter do I need?

If your interests are only in CW, then the sky is the limit when it comes to design. There are numerous simple solid state transmitter designs out there, using inexpensive FETs to generate power. I'm hoping, along with many others, that there will be a considerable amount of CW activity on 630m and even a simple 25-watter should provide you with lots of  fun. There may also be some appetite for QRSS CW which can give the weak-signal digital modes a run for their money while still using a simple transmitter.

If you are interested in digital modes, such as WSPR or JT-9, the easiest way is through the use of a transverter to take care of converting your HF transceiver's capabilities to LF or HF. There are presently a few commercial transverter options available and can be found on the NJDTechnologies links page.

A good choice is the inexpensive 630m transverter produced by John Molnar, shown below and available both as a kit or prebuilt. It works well and is very popular.

630m Transverter - John Molnar WA3ETD / WG2XKA
Although not available commercially, another popular 630m homebrew design is one from G3XBM which will also provide a way to get on the digital modes. He also has a 2200m design, should your interests be focused on that band.

G3XBM -630m Transverter
Any of these simple transverters are capable of controlling a higher-powered switching FET amplifier as your station progresses.

If you want something in the 'Collins category', the tranverters (both 2200m and 630m models) produced by VK4YB's Monitor Sensors provide around 70W output and are incredibly well designed and built. I have been very happily employing a 630m model for well over a year now ... my review of the transverter can be found here.

VK4YB - 630m Transverter
I suspect that we may soon see more commercial products become available over the next year but if you are handy with a soldering iron, building your transmitter will all be part of the 630m challenge!

I would like to put on a beacon. What do you suggest?

The best and most informational type of beacon is a WSPR mode beacon. A WSPR beacon operator can always determine where his beacon is being heard, in real time, along with how well it is being heard, by watching the uploaded 'spots' of his beacon on the WSPRnet. You will have much better coverage with this weak-signal mode beacon compared to one on CW ... for every CW report received, you would likely get ten times or more that number on WSPR.

Although WSPR is a great mode for checking out propagation, it's very easy to get into the habit of nightly beaconing and not developing your station any further. If you do run a WSPR beacon, be sure to try some of the other two-way modes such as CW or JT9 and call CQ regularly ... ham radio is all about making two-way contacts!

I don't have enough property for the large antennas required, so I won't be able to use these bands.

Even if you are limited in space, you can still enjoy these bands. There are many examples of stations on small city or suburban-size lots that are consistently heard across North America on 630m. If you have the room for an 80m or 40m dipole or inverted-L, that will be enough space to work these bands. An inverted-L for example, can be base-loaded and tuned to resonance. Along with several ground radials, even a small antenna system like this will allow you to work skywave DX or be heard across the country when propagation is good. I'm constantly amazed at how well these bands propagate with very low amounts of erp. Don't let living on a small lot stop you from exploring these bands!

All I hear is noise on these bands ... how can I use them if I can't hear anything?

Growing noise floors are common to everyone and this is often the biggest challenge for LF and MF operators, especially those in densely populated regions. Armed with a little knowledge and investigation, oftentimes seemingly impossible QRN can be substantially reduced if not eliminated entirely ... even easier when the noise source is found to be in your own home! While some amateurs just give up at this stage, most will see it as an interesting challenge to be overcome and part of the many learning experiences offered by these new bands.

In addition to the informational links provided above, I have just added a new 'Getting Started On 630m' page to my website. This page has a two-part article that I recently wrote for The Canadian Amateur, our national amateur radio journal. The articles describe a simple way of getting on 630m CW as well as providing some basic antenna information and ideas.

This blog also has extensive writings involving 630m over the past few years, describing equipment used and suggestions for new operators, much of it involving homebrewing. There are several links on the right that will take you to specific blogs dealing with 630m.

For present LF and MF operators here in Canada, the arrival of our American friends to these bands is generating much excitement and anticipation. The opening of these bands in the USA will pump new life into this part of the spectrum for all North American participants and the opportunities for homebrewing and experimenting are boundless. It should be a very exciting winter!

If you have not taken the 60 seconds required to register your station on the UTC webpage, please don't neglect to do this via the link provided above. There have, reportedly, been thousands of amateurs doing this already, as it effectively locks-out their locations for any future PLC deployment that might keep them off these bands at a later date.

See you in mid-October on 630!

VE7CNF / 630m Mobile … almost.

fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
If you think 160m mobile is a challenge...



Hot on the heels of his recent 630m maritime adventure, Toby (VE7CNF), continued to demonstrate the flexibility of his small 20W 630m portable system with an afternoon of fixed 'mobile' activity from his vehicle.








Local 630m op's in-boxes received a surprise alert on Tuesday:

"Are any of you available on Tuedsay for a 630m land mobile test with VE7CNF/7?"

Toby set things up at Sea Island's Iona Regional Park, situated on the ocean's edge just north of Vancouver International Airport. This gave him a good shot to several of the local 630m ops around the local region.

When Canadian amateurs first approached RAC and Industry Canada for a slice of spectrum near 500KHz, the main goal was to secure a frequency range that would support excellent groundwave propagation for a possible future emergency data network. Whether this will ever happen or not remains to be seen, but Toby's afternoon outing, along with the recent 630 marine mobile activity certainly helps to demonstrate the potential for the band to provide reliable signals with relatively small antennas and low erp.

Toby's basic transverter is rather unique in that the transmitter's FET power mixer also passes signals backwards to function in the receive mode:

"I’ve developed a 630m band linear transverter that produces 30W of transmitter power. It has no power amplifier and draws only 175 mA from a 12V power supply. It works for both transmit and receive with no T/R antenna relays or switching circuits.

I’ve used a bidirectional high-power mixer circuit to directly take 100W of power from a 160m band transceiver and produce useful output power on 630m. For receive, 630m signals can pass backwards through the circuit and are up-converted to 160m. 

My transverter is actually the small box on the dash above the steering wheel. The gear in the back near the variometer is used only during setup to resonate the antenna. It's a signal generator and oscilloscope. The AC transformers are just an isolation transformer that I need to make the test equipment work with my 12V-to-AC inverter."

Toby VE7CNF/7 at Iona
Toby's own report on the outing:

"VE7CNF/7 Operation was from the Iona Beach area near Vancouver, grid CN89jf. The location is right beside salt water. There are no nearby power lines so rx noise was S0. Operation was in daylight, around 4 pm local time. Signals were excellent and all CW was easy copy. 

On 475.0 kHz CW I managed to work Roger VE7VV (CN88il, him 529, me 579) and Jack VA7JX (CN79kv, him 569, me 579). I heard Steve VE7SL (CN88iu) at 599 briefly, then he had a problem and we didn't complete a QSO. He gave me 599 later by email.

The antenna is about 24 ft high and the fishing-rod-and-wire top load is pulled forward about 8 ft. The matching circuit is a loading coil, variometer, and autotransformer. My Tx power was 20W TPO and estimated EIRP 75 mW. The rig was my home brew transverter with an IC-7410."



"After CW I ran WSPR for a while, 23:42 to 00:08 UTC (4:42 to 5:08 pm local). WSPRnet lists my spots as my home QTH CN89ng, but I did have CN89jf entered in WSJT-X. I got spots from WI2XJQ -17, VE7BDQ +14, VE7AB +6, VE7VV +1, W7IUV -26, WH2XGP -30 dB. I also decoded WSPR from VE7VV +7 and VA7JX +9 dB."

"This was great fun. I'll have to try more locations, and see if I can improve the equipment for easier setup. I had great copy on Roger 529 and Jack 569. Working Jack was a surprise, and his signal was excellent. Being beside salt water is magic. Rx noise was so low at that location, near Iona Beach CN89jf."



Our 'new' band continues to demonstrate its ability to offer exciting opportunities to experimenters, home-brewers and DXers alike and for those with the creative imagination to push new boundaries, who knows where one of the first frequency ranges to be used by amateurs back in the 20's might eventually take us.

I can visualize, at some point in the future, the usefulness of a province-wide 630m emergency comms network utilizing a basic 'grab and go' system based on much of Toby's demonstrated work.

If you are a Canadian amateur why not join the fun on 630m now? U.S. amateurs will be arriving shortly and when they do, things should be getting even more exciting on the new band!

Digital Revolution Or Evolution?

courtesy: KD0WTE



A recent reflector posting tended to confirm a rather intriguing trend that I have also been noticing over the past few years.



The poster lamented the fact that he often found very few or even no CW / SSB signals on the HF bands while at the same time seeing lots of activity throughout the digital portion of the bands.

It does seem like there is far less CW and phone activity on the HF bands now, than there was a few years ago and there is no question that digital activity has soared. Whether it's RTTY, PSK31, JT65, WSPR, JT9 or others, these digital signals are always prominent and, band plan or not, are slowly migrating further in the band as activity increases ... but is this the reason for the decline of traditional modes?

The digital weak-signal modes make these extremely popular for a number of reasons. Nowadays, many amateurs are living in antenna-restricted communities and are forced to develop smaller, lower and less effective stealthy antenna systems if they wish to get on the air and make contacts. Most of these modes perform well with minimal amounts of power and are capable of hearing well into the noise ... and unless you live out in the country, with well-separated neighbours, we all know that noise is increasing at horrific levels almost everywhere. These two factors alone might well explain much of the growth in digital activity.

Licencing requirements have also been slowly evolving and today, getting a ticket is much easier than it was several decades ago ... and in many cases, without the requirements of knowing anything about CW. Every month, North Americans see a large number of new amateurs, many with no code skills and possibly not much interest in acquiring them. From my own local observations, most of these new amateurs usually head straight to FM on the VHF/UHF bands and have little knowledge of or interest in HF radio. These factors must also play into the demise of activity on the traditional HF modes as well.

We also shouldn't overlook the influence that Old Sol is having on our HF bands as well. Solar Cycle 24 (begun in 2008) has been one of the poorest on record and continues to generate month after month of terribly poor HF propagation. As a young SWL who listened in Cycle 19, (the largest on record), I can vouch for the relationship between HF activity and good propagation. Those were amazing days, when 20 and 15m would stay open all night long ... even 10m would often still be open with F2 propagation at midnight towards VK and ZL! Everyday, month after month, the bands were simply bulging with activity, from end to end ... high solar flux numbers bring high activity numbers and we are now experiencing the downside effects of what happens when the sun dreadfully underperforms. The only exception to band-bulging activity today seems to be limited to major contest weekends only. Where these people go the rest of the time is a mystery.

There are surely other reasons as well for the gradual decline of traditional-mode HF activity, including the fact that the general ham population is getting older. Large numbers of stations are simply 'going away' as interest or opportunity declines and as more of the aging traditional-mode ops go 'SK'. I know of several hams that have just given-up because of insurmountable increases in their local noise floors. Our new and usually younger hams, have largely grown up in the 'digital age' and for those that do find themselves exploring the HF bands without CW skills, might logically settle into the digital modes first.

Things are changing quickly, of that there is no doubt. Last summer, on 50mHz, I noticed a large increase in the number of dedicated CW operators moving to JT65 and JT9 during openings and this summer has already seen another huge migration from one mode to the other.

Although this year's Sporadic-E season is just getting started, I have already heard many more countries on JT65 than I have on the traditional modes (Japan, Philippines, China, Formosa, Alaska, Venezuela, Cuba, Brazil). Yesterday I listened to a PY calling CQ on CW for some length, with no takers, while it seemed most of the usual west coast ops were watching the digital band. I fear that many good QSO possibilities will be lost as more stations switch to the much slower digital modes ... on 6m, many of the openings last for a very short time making CW or SSB the quickest way to complete a contact. The other problem I notice this summer is that there are several JT sub-modes and it is often difficult or impossible to figure out which mode is being used let alone having the time to switch to the other mode before signals are gone ... perhaps a case of having too much of a 'good thing'? Hopefully one mode will emerge as the '6m standard' so all are on the same page.

What will be the long-term outcome of these changes remains to be seen but I suspect we'll see more and more of our HF CW and SSB spectrum space gradually shrinking to make room for more digital activity, likely to become the dominant modes eventually.

As a life-time, almost exclusive CW operator since age 15, I find this somewhat disheartening but must admit that over the past few years, I have found my own level of weak-signal digital activity increasing by leaps and bounds. These are powerful, capable modes and offer amateurs new and exciting challenges from VLF to nanowaves. Are they as exciting as my much-loved CW? Ask me in a couple of years!

Digital Revolution Or Evolution?

courtesy: KD0WTE



A recent reflector posting tended to confirm a rather intriguing trend that I have also been noticing over the past few years.



The poster lamented the fact that he often found very few or even no CW / SSB signals on the HF bands while at the same time seeing lots of activity throughout the digital portion of the bands.

It does seem like there is far less CW and phone activity on the HF bands now, than there was a few years ago and there is no question that digital activity has soared. Whether it's RTTY, PSK31, JT65, WSPR, JT9 or others, these digital signals are always prominent and, band plan or not, are slowly migrating further in the band as activity increases ... but is this the reason for the decline of traditional modes?

The digital weak-signal modes make these extremely popular for a number of reasons. Nowadays, many amateurs are living in antenna-restricted communities and are forced to develop smaller, lower and less effective stealthy antenna systems if they wish to get on the air and make contacts. Most of these modes perform well with minimal amounts of power and are capable of hearing well into the noise ... and unless you live out in the country, with well-separated neighbours, we all know that noise is increasing at horrific levels almost everywhere. These two factors alone might well explain much of the growth in digital activity.

Licencing requirements have also been slowly evolving and today, getting a ticket is much easier than it was several decades ago ... and in many cases, without the requirements of knowing anything about CW. Every month, North Americans see a large number of new amateurs, many with no code skills and possibly not much interest in acquiring them. From my own local observations, most of these new amateurs usually head straight to FM on the VHF/UHF bands and have little knowledge of or interest in HF radio. These factors must also play into the demise of activity on the traditional HF modes as well.

We also shouldn't overlook the influence that Old Sol is having on our HF bands as well. Solar Cycle 24 (begun in 2008) has been one of the poorest on record and continues to generate month after month of terribly poor HF propagation. As a young SWL who listened in Cycle 19, (the largest on record), I can vouch for the relationship between HF activity and good propagation. Those were amazing days, when 20 and 15m would stay open all night long ... even 10m would often still be open with F2 propagation at midnight towards VK and ZL! Everyday, month after month, the bands were simply bulging with activity, from end to end ... high solar flux numbers bring high activity numbers and we are now experiencing the downside effects of what happens when the sun dreadfully underperforms. The only exception to band-bulging activity today seems to be limited to major contest weekends only. Where these people go the rest of the time is a mystery.

There are surely other reasons as well for the gradual decline of traditional-mode HF activity, including the fact that the general ham population is getting older. Large numbers of stations are simply 'going away' as interest or opportunity declines and as more of the aging traditional-mode ops go 'SK'. I know of several hams that have just given-up because of insurmountable increases in their local noise floors. Our new and usually younger hams, have largely grown up in the 'digital age' and for those that do find themselves exploring the HF bands without CW skills, might logically settle into the digital modes first.

Things are changing quickly, of that there is no doubt. Last summer, on 50MHz, I noticed a large increase in the number of dedicated CW operators moving to JT65 and JT9 during openings and this summer has already seen another huge migration from one mode to the other.

Although this year's Sporadic-E season is just getting started, I have already heard many more countries on JT65 than I have on the traditional modes (Japan, Philippines, China, Formosa, Alaska, Venezuela, Cuba, Brazil). Yesterday I listened to a PY calling CQ on CW for some length, with no takers, while it seemed most of the usual west coast ops were watching the digital band. I fear that many good QSO possibilities will be lost as more stations switch to the much slower digital modes ... on 6m, many of the openings last for a very short time making CW or SSB the quickest way to complete a contact. The other problem I notice this summer is that there are several JT sub-modes and it is often difficult or impossible to figure out which mode is being used let alone having the time to switch to the other mode before signals are gone ... perhaps a case of having too much of a 'good thing'? Hopefully one mode will emerge as the '6m standard' so all are on the same page.

What will be the long-term outcome of these changes remains to be seen but I suspect we'll see more and more of our HF CW and SSB spectrum space gradually shrinking to make room for more digital activity, likely to become the dominant modes eventually.

As a life-time, almost exclusive CW operator since age 15, I find this somewhat disheartening but must admit that over the past few years, I have found my own level of weak-signal digital activity increasing by leaps and bounds. These are powerful, capable modes and offer amateurs new and exciting challenges from VLF to nanowaves. Are they as exciting as my much-loved CW? Ask me in a couple of years!

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