QRP ARCI Spring QSO Party this weekend
2017 QRP-ARCI(sm) SPRING QSO PARTY
Date/Time:
1200Z on 8 April 2017 through 2400Z on 9 April 2017. You may work a maximum of 24 hours of the 36 hour period.
Mode: HF CW only.
Exchange:
Members send: RST, State/Province/Country, ARCI member number
Non-Members send: RST, State/Province/Country, Power Out
QSO Points:
Member = 5 points
Non-Member, Different Continent = 4 points
Non-Member, Same Continent = 2 points
Multiplier:
SPC (State/Province/Country) total for all bands. The same station may be worked on multiple bands for QSO points and SPC credit.
Power Multiplier:
>5 Watts = x1
>1 - 5 Watts = x7
>250 mW - 1 Watt = x10
>55 mW - 250 mW = x15
55 mW or less = x20
Suggested Frequencies:
160m - 1810 kHz
80m - 3560 kHz
40m - 7030 kHz (please listen at 7040 kHz for rock bound participants)
20m - 14060 kHz
15m - 21060 kHz
10m - 28060 kHz
Score:
Final Score = Points (total for all bands) x SPCs (total for all bands) x Power Multiplier.
BONUS POINTS: None available for this contest.
Categories:
Entry may be All-Band, Single Band, High Bands (10m-15m-20m) or Low Bands (40m-80m)
How to Participate:
Get on any of the HF bands except the WARC bands and hang out near the QRP frequencies. Work as many stations calling CQ QRP or CQ TEST as possible, or call CQ QRP or CQ TEST yourself! You can work a station for credit once on each band.
Log Submission:
Submit your entry online at http://www.qrpcontest.com
Contest logs are not required for entry, but may be requested by the Contest Manager if required.
Deadline: Entries must be postmarked on or before 23 April 2017.
Results: Will be published in QRP Quarterly and shown on the QRP-ARCI website.
Certificates: Will be awarded to the Top 10 Scoring Entrants.
Hopefully, I'll see you on the air at some point this weekend! (At least this year, the contest doesn't fall on Easter Weekend!)
72 de Larry W2LJ
QRP - When you care to send the very least!
Larry Makoski, W2LJ, is a regular contributor to AmateurRadio.com and writes from New Jersey, USA. Contact him at [email protected].
QRP ARCI Spring QSO Party this weekend
2017 QRP-ARCI(sm) SPRING QSO PARTY
Date/Time:
1200Z on 8 April 2017 through 2400Z on 9 April 2017. You may work a maximum of 24 hours of the 36 hour period.
Mode: HF CW only.
Exchange:
Members send: RST, State/Province/Country, ARCI member number
Non-Members send: RST, State/Province/Country, Power Out
QSO Points:
Member = 5 points
Non-Member, Different Continent = 4 points
Non-Member, Same Continent = 2 points
Multiplier:
SPC (State/Province/Country) total for all bands. The same station may be worked on multiple bands for QSO points and SPC credit.
Power Multiplier:
>5 Watts = x1
>1 - 5 Watts = x7
>250 mW - 1 Watt = x10
>55 mW - 250 mW = x15
55 mW or less = x20
Suggested Frequencies:
160m - 1810 kHz
80m - 3560 kHz
40m - 7030 kHz (please listen at 7040 kHz for rock bound participants)
20m - 14060 kHz
15m - 21060 kHz
10m - 28060 kHz
Score:
Final Score = Points (total for all bands) x SPCs (total for all bands) x Power Multiplier.
BONUS POINTS: None available for this contest.
Categories:
Entry may be All-Band, Single Band, High Bands (10m-15m-20m) or Low Bands (40m-80m)
How to Participate:
Get on any of the HF bands except the WARC bands and hang out near the QRP frequencies. Work as many stations calling CQ QRP or CQ TEST as possible, or call CQ QRP or CQ TEST yourself! You can work a station for credit once on each band.
Log Submission:
Submit your entry online at http://www.qrpcontest.com
Contest logs are not required for entry, but may be requested by the Contest Manager if required.
Deadline: Entries must be postmarked on or before 23 April 2017.
Results: Will be published in QRP Quarterly and shown on the QRP-ARCI website.
Certificates: Will be awarded to the Top 10 Scoring Entrants.
Hopefully, I'll see you on the air at some point this weekend! (At least this year, the contest doesn't fall on Easter Weekend!)
72 de Larry W2LJ
QRP - When you care to send the very least!
Larry Makoski, W2LJ, is a regular contributor to AmateurRadio.com and writes from New Jersey, USA. Contact him at [email protected].
Irony
The FCC issued Report and Order 17-33 which creates two new bands for amateur radio, 472-479 kHz (630 meters) and 135.7-137.8 kHz (2,200 meters). As ARRL reported, it is a “big win” for amateur radio. I’ve been waiting in anticipation for the 630 meter band as it’s an old yet new frontier for us. With old Sol taking a bit of a nap for the past few years and perhaps for years or decades to come, lower frequencies are where we’re going to have to play for more fun.
There are a few caveats in using these bands. The FCC is requiring radio amateurs be at least 1 km from electric power transmission lines using Power Line Carrier (PLC) systems on those bands. PLC is a technology that uses low frequency signals on power lines to perform signaling and control functions, and often meter reading. Amateurs will have to notify the Utilities Technology Council (UTC) of station location prior to operating on 630 and 2200 meters. The UTC maintains an industry database for PLC operations.
Those who were around to experience the Broadband over Powerline (BPL) brouhaha around 2003 to 2005 may recall the UTC organization. At the time BPL was billed by proponents as the next big thing in broadband Internet. Amateur radio operators and ARRL argued vigorously against BPL, citing engineering and evidence that the HF signals on the power lines radiated into the ether and interfered with HF radio operations. The FCC turned a blind eye to the issue. Luckily market forces took out BPL as a viable broadband solution due to increasing bandwidth needs and numerous failed trials which uncovered its technical difficulties and business problems. PLC and BPL are cousins, with PLC operating below 500 khz and HF BPL operating from 1.8 to 30 Mhz.
The UTC, several electric utilities, and a handful of BPL equipment vendors at the time claimed that BPL didn’t interfere with HF radio operations. The explanations and claims baffled those of us experienced in wireless and RF engineering as it’s a fact that an unshielded conductor tens of wavelengths long, conducting RF signals, will radiate energy. The math and science supported this and measurements in the field provided real life evidence.
The UTC notes the following about PLC operation:
“This Activity is established as provided for in the FCC Rules and Regulations, Part 90.35(g) (47 C.F.R. ‘ 90.35(g)) relative to PLC operation in the 10-490 kHz band, and the NTIA Manual of Regulations and Procedures for Federal Radio Frequency Management, in Part 8.3, under the heading “Notifications in the Band 10-490 kHz,” (see 47 C.F.R., Chapter III). Electric utilities are allowed to use power line carrier (PLC) transmitters and receivers for control signals and information transmission in the 10-490 kHz band without obtaining a license from the [FCC]. However, PLC users are not protected from interference from licensed radio transmitters.”
Part 90.35(g) states that PLC operates under Part 15. With the distance separation and notification requirement for amateurs, the FCC has granted an unlicensed incidental radiating non-wireless service protection from a licensed wireless service. This was essentially the case with BPL in the early 2000s with an unworkable process for resolving interference issues, and interference complaints from amateurs living in trial site areas languishing for months with no action.
With this latest frequency allocation to amateur radio and requirements for protecting PLC operations, the tables are turned. It’s the electric utility industry, that once claimed power lines wouldn’t interact with wireless spectrum, that could potentially experience interference. Undoubtedly many FCC staffers involved in BPL in the past are no longer at the agency and the electric utility industry has forgotten about the BPL fiasco and fail to realize the irony of needing to protect PLC from wireless.
All this being said, I’m not attempting to downplay or criticize the allocation of the two new bands. I think it’s wonderful and I applaud ARRL’s success. However, I hope amateurs wishing to enjoy these bands aren’t prevented in doing so. While it’s unlikely a large number of amateurs will be excluded from operating due to PLC on high voltage transmission lines, PLC systems are used in meter reading applications in neighborhood power distribution systems. Hopefully the majority of systems do not operate in the new 630 and 2200 meter amateur bands and we can peacefully coexist, unlike what occurred with BPL.
Anthony, K3NG, is a regular contributor to AmateurRadio.com.
The Artwork Of DK1IS

Recent discussion on the RSGB LF Group reflector about high-powered LF / MF amplifiers brought an interesting response from Tom, DK1IS, and his unique solution.
It's no secret that a Class D / E amplifier using switching MOSFETs is a popular and reasonably inexpensive method of generating some serious RF on the LF and MF bands. Equally well-known is their propensity to gobble-up FETs should the amplifiers encounter much reactance in their output load. Most builders include some form of protection for sudden over-current or unwanted SWR excursions which will shut down the amplifier before any FETs can self-destruct. Those that don't usually end up replacing FETs.
I would venture to guess that over 90% of the transmitters now being employed on LF or MF are using switching MOSFETs in a Class D / E design but there are some amateurs using vacuum tubes to do their heavy-lifting ... and with good results.
DK1IS's beautiful homebrew amplifier is shown below. Tom provided the following description:
Hi Wolf and group,
nice to hear that someone else is thinking about this approach! I´m
content with my homemade tube PA for LF and MF which has provided
reliable service since nearly 4 years now. Only some thoughts about this
concept - I hope not to bore all those hams who are happy with their
semiconductor PAs:
Years ago I had a MOSFET PA for LF, Class B push-pull with 250 W RF. It
worked well at constant conditions, but when I had to retune the antenna
due to larger QSY or made antenna experiments there always was the
danger of blowing up these nervous semiconductors. After 4 or 5 times
changing the MOSFETS I decided to build a new PA - with tubes! Looking a
little bit anachronistic this PA is absolutely good-natured. Designed for
broadband service on LF and MF it makes no problems when changing the
antenna coarse tuning from one band to the other even when the fine
tuning isn't done yet. With my former MOSFET-PA this would have been
impossible.
I wanted to have a linear PA - this usually means class B. You have to
decide between narrow band and broad band (like an audio-amp) design.
For narrow band you can use a single-ended PA but you have to add a
resonance circuit. For broad band you should use a push-pull PA and have
to build a suitable output transformer. I opted for broad band design
because it is usable for LF and MF without changes at the PA. With this
design and sin-driving I reach a total harmonic distortion of about 5 %
at 700 W RF on a pure resistive dummy load. With the usual narrow,
narrow band antennas on LF and MF you don´t need additional filters!
Concerning the tubes: If you take the common TX tubes with plate
voltages of several kV all output circuits have rather high impedances,
that means large coils for the resonance circuits resp. large
transformer windings and very high voltages - potentially a construction
problem. This led me to the choice of 2x 4x PL519 in push-pull, a rugged
colour TV line output tube with low plate voltage and high plate
current. In this way I came down to a plate-to-plate resistance of about
1 kOhm at 600 V DC plate voltage, where you easily can build a ferrite
broad band output transformer down to 50 Ohms. A disadvantage of this
concept is that you have to give individual bias to each tube, that
means for the first start-up you have to align 8 potentiometers
carefully to nearly equal cathode currents for all the tubes. But
according to my experience this alignment remains stable over a long
time. I have inserted 1-Ohm-resistors in each cathode line and have
brought the voltage drops to 8 cinch connectors, where I can monitor the
DC component (with external filtering) as well as the real time current.
With 4 tubes in parallel per branch of course you have to take care for
self oscillations. The extensive use of bypass capacitors, ferrite beads
and parasitic chokes in the plate lines is mandatory as well as good
grounding concepts are. The tubes don´t pull control grid current (this
would even be true in class C!) but you need 3 or 4 W RF input power due
to all the ohmic loads at the tube´s control grids caused by the
individual bias paths. On the other hand this certainly helps to avoid
oscillations. You can see some pictures of this PA at https://www.qrz.com/db/DK1IS
By the way: why not to try these tubes at class D? With DC plate
voltages of perhaps 1200 V you should get a nice QRO-PA ...
Wolf, you are right: building such a PA from scratch is a time consuming
enterprise. I didn´t count the working hours but according to my lab log
the whole project took about 9 months - an adequate time for a new baby!
It was a great experience anyway.
Good luck and 73,
Tom, DK1IS
![]() | ||
| 2x 4x PL519 Push-Pull |
![]() |
| TX, power supply, RX, exciter |
DK1IS has provided an inspiring example of what can be done using vacuum tubes ... they certainly should not be discounted as a viable method of generating your hard-earned LF / MF ERP.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].
The Artwork Of DK1IS

Recent discussion on the RSGB LF Group reflector about high-powered LF / MF amplifiers brought an interesting response from Tom, DK1IS, and his unique solution.
It's no secret that a Class D / E amplifier using switching MOSFETs is a popular and reasonably inexpensive method of generating some serious RF on the LF and MF bands. Equally well-known is their propensity to gobble-up FETs should the amplifiers encounter much reactance in their output load. Most builders include some form of protection for sudden over-current or unwanted SWR excursions which will shut down the amplifier before any FETs can self-destruct. Those that don't usually end up replacing FETs.
I would venture to guess that over 90% of the transmitters now being employed on LF or MF are using switching MOSFETs in a Class D / E design but there are some amateurs using vacuum tubes to do their heavy-lifting ... and with good results.
DK1IS's beautiful homebrew amplifier is shown below. Tom provided the following description:
Hi Wolf and group,
nice to hear that someone else is thinking about this approach! I´m
content with my homemade tube PA for LF and MF which has provided
reliable service since nearly 4 years now. Only some thoughts about this
concept - I hope not to bore all those hams who are happy with their
semiconductor PAs:
Years ago I had a MOSFET PA for LF, Class B push-pull with 250 W RF. It
worked well at constant conditions, but when I had to retune the antenna
due to larger QSY or made antenna experiments there always was the
danger of blowing up these nervous semiconductors. After 4 or 5 times
changing the MOSFETS I decided to build a new PA - with tubes! Looking a
little bit anachronistic this PA is absolutely good-natured. Designed for
broadband service on LF and MF it makes no problems when changing the
antenna coarse tuning from one band to the other even when the fine
tuning isn't done yet. With my former MOSFET-PA this would have been
impossible.
I wanted to have a linear PA - this usually means class B. You have to
decide between narrow band and broad band (like an audio-amp) design.
For narrow band you can use a single-ended PA but you have to add a
resonance circuit. For broad band you should use a push-pull PA and have
to build a suitable output transformer. I opted for broad band design
because it is usable for LF and MF without changes at the PA. With this
design and sin-driving I reach a total harmonic distortion of about 5 %
at 700 W RF on a pure resistive dummy load. With the usual narrow,
narrow band antennas on LF and MF you don´t need additional filters!
Concerning the tubes: If you take the common TX tubes with plate
voltages of several kV all output circuits have rather high impedances,
that means large coils for the resonance circuits resp. large
transformer windings and very high voltages - potentially a construction
problem. This led me to the choice of 2x 4x PL519 in push-pull, a rugged
colour TV line output tube with low plate voltage and high plate
current. In this way I came down to a plate-to-plate resistance of about
1 kOhm at 600 V DC plate voltage, where you easily can build a ferrite
broad band output transformer down to 50 Ohms. A disadvantage of this
concept is that you have to give individual bias to each tube, that
means for the first start-up you have to align 8 potentiometers
carefully to nearly equal cathode currents for all the tubes. But
according to my experience this alignment remains stable over a long
time. I have inserted 1-Ohm-resistors in each cathode line and have
brought the voltage drops to 8 cinch connectors, where I can monitor the
DC component (with external filtering) as well as the real time current.
With 4 tubes in parallel per branch of course you have to take care for
self oscillations. The extensive use of bypass capacitors, ferrite beads
and parasitic chokes in the plate lines is mandatory as well as good
grounding concepts are. The tubes don´t pull control grid current (this
would even be true in class C!) but you need 3 or 4 W RF input power due
to all the ohmic loads at the tube´s control grids caused by the
individual bias paths. On the other hand this certainly helps to avoid
oscillations. You can see some pictures of this PA at https://www.qrz.com/db/DK1IS
By the way: why not to try these tubes at class D? With DC plate
voltages of perhaps 1200 V you should get a nice QRO-PA ...
Wolf, you are right: building such a PA from scratch is a time consuming
enterprise. I didn´t count the working hours but according to my lab log
the whole project took about 9 months - an adequate time for a new baby!
It was a great experience anyway.
Good luck and 73,
Tom, DK1IS
![]() | ||
| 2x 4x PL519 Push-Pull |
![]() |
| TX, power supply, RX, exciter |
DK1IS has provided an inspiring example of what can be done using vacuum tubes ... they certainly should not be discounted as a viable method of generating your hard-earned LF / MF ERP.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].
The Spectrum Monitor — April, 2017
Stories you’ll find in our April, 2017 issue:
Going Portable with Amateur Radio Satellites
By Keith Baker KB1SF/VA3KSF
Low solar cycle productivity and plummeting propagation got you down? Keith tells us that the sky’s the limit when you start operating the amateur radio satellites. It’s a low-power mode that is also versatile. But, don’t worry, working the AMSATs doesn’t require a lot of room at home, can be fairly inexpensive to set up and you can take this part of the hobby on the road too!
Community Emergency Response Teams: Are You Ready for a Disaster?
By Alan M. Vigeant N6HPO
Community Emergency Response Team (CERT) is a nationwide volunteer program supported by FEMA that educates people about disaster preparedness for natural and man-made hazards that may impact their lives when least expected. CERT classes are offered free to the public and go hand in hand with amateur radio training. Alan tells us how effective CERT is and how we can all help.
Outernet Update: Free, One-Way Internet Now Via L-Band Satellite
By Kenneth Barbi
Outernet is the low cost, one-way Internet service that delivers radio and news feeds to nearly the entire planet for free via L-band satellite. Designed to meet the minimal needs of those without modern infrastructure (grid power and Internet access), all you need to start taking advantage of this service is a $79 kit that includes antenna, LNA, SDR radio and CHIP single-board computer. Kenneth Barbi has the latest update on this evolving service.
Computers and Ham Radio: Part 010
By Cory GB Sickles WA3UVV
From the Radio Shack TRS-80 to the Apple II, to IBM’s first PC and the inevitable first PC clone, personal computing started out as an expensive device with very limited capability. From its initially slow start in the 1970s, Cory takes us through the fits and starts of the second phase of this fledgling industry that would change the radio hobby forever.
Motorized Ku-Band Satellite Reception
By Mike Kohl
There are dozens of Ku-band satellites in the skies over every part of the world. And, while Free-to-Air satellite TV systems are very inexpensive, you miss most of the action by not being able to steer your dish from satellite to satellite. But, not all small dish motors are the same. Mike shows us the best way to motorize your own FTA satellite system.
Scanning America
By Dan Veeneman
Marin County (CA), North Dakota and Radio Shack Bankruptcy (Again)
Federal Wavelenghts
By Chris Parris
Federal Aviation Administration
Utility Planet
By Hugh Stegman
New Life Evolves on MARS
Shortwave Utility Logs
By Hugh Stegman and Mike Chace-Ortiz
Digitally Speaking
By Cory GB Sickles WA3UVV
The Ground We Talk On
VHF and Above
By Joe Lynch N6CL
New Radios and Antennas for VHF and Above
Amateur Radio Insights
By Kirk Kleinschmidt NT0Z
Morse Code: The Original Digital Mode is Still Hanging On
Radio 101
By Ken Reitz KS4ZR
Baseball on the Radio: 1921 and 2017
Radio Propagation
By Tomas Hood NW7US
An Ice Age and Disappearing Sunspots?
World of Shortwave Listening
By Rob Wagner VK3VBW
Radio Australia: A Possible Return?
The Shortwave Listener
By Fred Waterer
VOA at 75; WBCQ, RRI, and RNZI
Maritime Monitoring
By Ron Walsh VE3GO
A System for a System
The Longwave Zone
By Kevin O’Hern Carey WB2QMY
Turning the Tables: Reverse Beacon Network
Adventures in Radio Restoration
By Rich Post KB8TAD
Philco 46-350: The “Tambour Door” Portable
Antenna Connections
By Dan Farber AC0LW
HF Antenna “Comfort Zone”
The Spectrum Monitor is available in PDF format which can be read on any desktop, laptop, iPad®, Kindle® Fire, or other device capable of opening a PDF file. Annual subscription is $24. Individual monthly issues are available for $3 each.
Ken Reitz, KS4ZR, is publisher and managing editor of The Spectrum Monitor. Contact him at [email protected].
ICQ Podcast Episode 234 – Portable Power Distribution
In this episode, Martin M1MRB / W9ICQ is joined by Edmund Spicer M0MNG and Chris Howard M0TCH to discuss the latest Amateur / Ham Radio news. Colin M6BOY rounds up the news in brief, and this episode’s features is Portable Power Distribution
We would like to thank William Hester N0LAJ and our monthly and annual donors for keeping the podcast advert free. To donate, please visit - http://www.icqpodcast.com/donate
- New Ham Radio Regulations in Netherlands
- IRTS Ham Radio Publications Archive
- 21 New US Hams
- Pocket Prefix for Android
- Students in Belize Introduced to Amateur Radio
- ARRL Wants Exclusion from California Law
- 5000 Australian Spectrum Intruders
- Map of Italian Ham Radio Repeaters
Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].















