My Moonrise

This week I had several days of unobstructed ocean moonrises as the Moon peaked on its monthly northern declination track. Thanks to the recent topping of my next door neighbour's large Douglas Fir, and removal of low-hanging branches, I am now able to track moonrises a little further to the south than before and can add two more EME days that were previously blocked by the large tree. All operations are on 2m JT65B mode, using a 9el Yagi and 140W output.




When I started (April 1) conditions looked as if they should be good, with lunar perigee (Moon's closest approach), degradation (background skynoise) and declination all looking favorable, but I was in for a surprise.

The rising yellow plot indicates the Earth-Moon distance growing further apart (increasing path losses) while the red plot indicates fluctuation in daily skynoise (temperature) near the moon. The blue plot indicates declination track from north to south ... for me, the higher the better.

courtesy: http://www.mmmonvhf.de/eme.php

Listening on the first two days (April 1-2) produced a few weak signals from the larger stations only and nothing from the more common '4-Yagi' stations and, no QSO's ... something was amiss. I can only attribute this to some real-time solar flaring during this two-day period and the resultant short term geomagnetic agitation the flares produced ... but almost as if the 'switch' had been flipped, the third day proved to be much different.

On day three, five new 'initials' were worked including one new state (New York) and two new DXCC countries! Truly surprising was that two of the stations worked were using just two Yagis, with both stations answering one of my 'CQ's.

Good conditions continued for the next few days, bringing my initials count from #87 to # 95, with the following stations all going into the log, turning a disappointing start into one of the best lunar sessions I have encountered:

HA6NQ, LZ2FO (two 13 el Yagis), EB5EEO, K2ZJ (two 14 el Yagis), DK5YA, S52LM, F8DO, PA5Y, SV6KRW, UA3PTW, OK1UGA.

April's operation brought  my 2m DXCC count to 29 and states worked total to 27.

SV6KRW's 4 x 8el Array

EB5EEO's 4 x 32el Cross-polarized Array (16V / 16H)

DK5YA's 4 x 22 Cross-polarized Array (11V / 11H)

As mentioned in my last EME report, I keep wondering when I will run out of stations that are able to hear my small station, forcing me to build a bigger amplifier for a few more precious db, but with the ability to occasionally work some 2-Yagi stations, the list of potential targets has increased dramatically ... perhaps the large Fir tree was a bigger attenuator than I had thought.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.

I hope to get on!  But it looks busy - VE Exams tomorrow morning, followed by grocery shopping and some house chores.  Sunday afternoon is our monthly stint at the soup kitchen, so maybe some time in between chores and possibly Saturday evening?  I sure hope so!  I have not been on the air much lately and I'm feeling that tug to get on more.  Again, not that I'm that much into contesting; but the idea to flex some CW muscle and fatten up the log book is appealing.

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].

I hope to get on!  But it looks busy - VE Exams tomorrow morning, followed by grocery shopping and some house chores.  Sunday afternoon is our monthly stint at the soup kitchen, so maybe some time in between chores and possibly Saturday evening?  I sure hope so!  I have not been on the air much lately and I'm feeling that tug to get on more.  Again, not that I'm that much into contesting; but the idea to flex some CW muscle and fatten up the log book is appealing.

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].

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.

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

As 'day one' for U.S. amateurs gaining their new LF / MF bands draws closer, many are seriously thinking about building or modifying rigs to get on the air. I'm sure the use of switching MOSFET amplifiers will still reign supreme when it comes to decision-making time but with some feeling more comfortable with tube technology, especially when used for power amplifiers, I suspect we will see some interesting tube transmitters being employed as well. I'm sure that some will even seek to modify older tube rigs, knowing that a pair of 6146's can muster enough power to have plenty of fun on the new band as well.

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].

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

As 'day one' for U.S. amateurs gaining their new LF / MF bands draws closer, many are seriously thinking about building or modifying rigs to get on the air. I'm sure the use of switching MOSFET amplifiers will still reign supreme when it comes to decision-making time but with some feeling more comfortable with tube technology, especially when used for power amplifiers, I suspect we will see some interesting tube transmitters being employed as well. I'm sure that some will even seek to modify older tube rigs, knowing that a pair of 6146's can muster enough power to have plenty of fun on the new band as well.

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].