Tests Of New Active MW Antennas

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Tests Of New Active MW Antennas
Dallas Lankford, 11/22/2011, rev. 3/7/2012
The Quoddy Head 2011 DXpedition (at Quoddy House, the Eastern most privately owned house in the continental USA, on
Quoddy Head, near Lubec, Maine) was not primarily a DXpedition. It was a test of new antennas which I invented and
have been developing for the better part of 2011. Schematics and diagrams of some of the new MW antennas are at the end
of this article. The results of these tests have shown that the new dual arrays are superior to 1000 foot terminated beverage
antennas for MW DXing and that the quad arrays are more superior to 1000 foot terminated beverage antennas for MW
DXing. The receiver was a Perseus, the laptop was a Lenovo W520 with I7 quad core and multiple 2
nd
HD's via plug-in
caddies resembling CD drives. A separately grounded common mode choke was used at the antenna input of Perseus.
Nevertheless, before TA signal levels rose to sufficiently high levels, noise was experienced from the W520 switching
power supply unless the W520 was operated on battery power. Next time I will bring spare batteries and more common
mode chokes.
Originally the primary purpose of the 2011 Quoddy Head DXpedition was to test a dual active delta flag array (DADFA), a
(non-variable) phased dual delta flag array with high performance FET followers attached directly to the antenna elements
(no antenna transformers).
The FET followers are now available from Clifton Laboratories
.
The DADFA was
erected on the afternoon of Nov. 2 pointing 60 degrees azimuth with the "null end" pointed at Quoddy House (the Eastern
most, privately owned house in the continental USA, where the Perseus receiver was located) and with the "null end" of the
DADFA about 30 feet away from Quoddy House. Comparisons were made with a terminated 1000 foot long BOG (T 1Kft
BOG) also pointing 60 degrees azimuth with starting point about 200 feet away from Quoddy House, and the BOG also 200
feet or more away from the DADFA. The first two nights the DADFA did not perform correctly because of a wiring
mistake which was not found and corrected until the morning of Nov. 4.
Nov. 4, 2011 early afternoon: The first TA carrier this afternoon was 1521 Saudi Arabia about 1650 UTC. No audio, just
barely visible on the Perseus display. First audio was around 1730, but you could only tell that someone was talking. The
language was identifiable occasionally about 1800, so I started comparisons of the T 1Kft BOG and DADFA at 1800. I hate
to admit it, but the T 1Kft BOG won. What little audio there was, was clearer on the T 1Kft BOG than on the DADFA. But
the DADFA was not the only new antenna being tested. About 1830 UTC I went outside and converted the DADFA to a
dual active grounded delta flag array (equivalent to a dual active delta EWE array, and which I will call a DAgDFA) which
has 6 dB more signal output than the DADFA. I also added a 13.6 dB gain push-pull Norton transformer feedback
amplifier. Tests resumed with this arrangement shortly after 1830 UTC and for a short period of time the competition was
neck and neck......................... But as the afternoon deepened, and TA signal strengths continued to increase, the higher
signal output of the DAgDFA became unnecessary, so I went back outside and ungrounded the antenna elements (grounded
delta flags are EWE's, and dual EWE arrays have poorer splatter reduction than dual flag arrays).
After about 1930 UTC the comparison of the DADFA and T 1Kft BOG continued. During this "sunset transition" as I call
it, there was little difference in performance between the DADFA and T 1Kft BOG because during sunset transition the
nulls of single antennas (beverages, flags, EWE's, etc.) and antenna arrays are degraded (for reasons that none of us
understand clearly). It is only after sunset, usually an hour or so after sunset, that the patterns of directional MW antennas
stabilize to their best patterns. After sunset transition was complete, the DADFA was superior to the T 1Kft BOG on about
85% of TA signals because of the DADFA superior splatter reduction. In some cases the difference was dramatic; TA's were
heard clearly (albeit with some splatter) on the DADFA, but were virtually inaudible on the T 1Kft BOG (due to much
heavier splatter). For the remaining 15% they were about equal in splatter reduction. In no case did the T 1K BOG have
better splatter reduction than the DADFA.
THE BOTTOM LINE
The DADFA, when grounding is used pre sunset (and occasionally later as I will explain below), is a better MW DX
antenna at a good low noise coastal site than a T 1Kft BOG.
The DADFA is a beverage killer.
At places like Grayland where 700' BOG's are the longest feasible (unless you trespass on other property), a Grayland
beverage would be a more distant 3rd. At Kongsfjord a 1000' unterminated (grounds have not been successfully used at
Kongsfjord because its ground is almost solid rock) beverage for listening to the USA would be a distant 4th.
There was one occasion at the bottom end of the MW band (about 531 to, say 600 kHz) well after sunset when the S/N ratio
of some TA's was not quite as good on the DADFA as on the T 1K BOG. This may be due to the noise floor of the flag
antennas (the thermal noise emitted by the 1K terminating resistors) becoming evident at the low end of the MW band
because when I went outside and grounded the DADFA array again, the S/N ratio difference had disappeared. It was not
1
splatter that changed, but hiss. Since the hiss was slight, I see no reason to use grounded DADFA's after sundown because
the hiss did not significantly affect intelligibility. However, this effect was not observed on subsequent nights, so it could
have been propagation of IBOC or antenna pattern change which was responsible for these observations.
Want A Simple 200 Foot Long Antenna
With Performance Equal To Or Better Than A 1000 Foot Long Terminated Beverage For MW DXing?
Shortly before departing Ruston for Quoddy Head I was studying theoretical properties of WOG (= short wire on ground)
arrays using EZNEC 5 and I discovered that according to EZNEC a quad WOG array with 95 foot WOG elements had a
null pattern almost as good as a QDFA. A passive quad 95' WOG array would obviously be insensitive, but what if the 95'
elements were activated with FET followers? I tested a single 95' active WOG just before leaving Ruston, and its signal
output was equal to the signal output of a full size active grounded delta flag element. As back-up, I had shipped a complete
spare DADFA (including a 2nd pair of FET followers). I could have used the spare to implement a quad active delta flag
array and embarrass the T 1Kft BOG even more, but why beat a dead horse?
These active WOG arrays might be called QA95A and DA95A, but since they will always be active arrays, I will call them
Q95 and D95. EZNEC predicted that a D95 (dual 95' WOG array) would not have good splatter reduction, about equal to a
T 1Kft BOG. But was the sensitivity of a D95 equal to or better than a T 1Kft BOG? So on the morning of 11-5 the T 1Kft
BOG was removed, and a D95 was implemented pointed 60 degrees azimuth with 200 feet twin lead lead-ins. The spacing
between centers of the WOG's was the standard 100 feet that I use for my small arrays, so the total length of the D95 was
195 feet. The null end of the D95 was about 100 feet from the power line feeder to Quoddy House. The D95 was somewhat
further from the main power line than the T 1Kft BOG had been, maybe 200 feet. Testing of the D95 began about 1830
UTC. Some TA signals had already reached audibility, so comparison of the D95 and DAgDFA commenced immediately.
By 1930 UTC when there were numerous TA's at good strength it was clear that the sensitivity of the D95 was equal to the
sensitivity of a DAgDFA, so the D95 sensitivity equaled the sensitivity of a T 1Kft BOG. After sunset transition was
completed, the splatter reduction of the D95 could be compared to the splatter reduction of the DADFA. As expected, the
splatter reduction of the D95 was not as good as the splatter reduction of the DADFA. On the other hand, the splatter
reduction of the D95 was about the same as a T 1Kft BOG. So if you don't want to mess with masts and delta antenna
elements with terminating resistors, and you don't have space for a 1000 foot beverage, a D95 may be the antenna for you.
The Q95 Has Much Better Splatter Reduction Than A 1000 Foot Terminated BOG
The Q95 (quad active 95' wire on ground (WOG) elements spaced 100 feet between centers) became active about 1830
UTC 11-6. The Q95 showed its right stuff immediately by having better S/N ratios on some weak middle East TA DX
compared to the only other reasonable antenna I had left, a single passive (but amplifier at the receiver) flag antenna, which
has splatter reduction about equal to a 1000' terminated BOG. As is well known, single larger than usual flag antennas
called SuperLoops have been the antenna of choice at
; no European beverages in 2009, and no beverages
at all mentioned in 2010. Of course, there were frequencies where the Q95 produced clear audio, while the flag produced
no audio, but not nearly as many as I expected. Except for requiring four FET followers, the Q95 is easy to set up (no masts
required, and only 4 relatively short ground rods... I use 2 foot long pieces of half inch OD galvanized electrical conduit cut
from longer pieces using a small hand held pipe cutter... when the galvanized surface begins to oxidize I throw them away
and cut new ones). The only small antenna likely to be better than a Q95 is a quad active delta flag array.
The phaser used for the Q95 was the same phaser that was used for the QDFA at Grayland before the isolating amplifier was
added. I did not use an isolating amplifier because I had no way of knowing in advance if an isolating amplifier was needed
or not for the Q95. It appears not. Occasionally a loop antenna was made from the single passive flag antenna by jumping
the terminating resistor. After low band TA signals rose to a sufficiently high level, many TA's were heard well on the single
flag antenna, but much better on the Q95, and mostly not at all on the loop (the loop null was pointed NNW into Canada,
and SSW into the Atlantic Ocean). Clearly the Q95 does not suffer from the same low band null loss that the QDFA suffered
from at Grayland. Part of the reason may be that the twin lead from the phaser-combiner near the center of the Q95 array to
Quoddy House as only 200 feet long, while the lead in from the phaser-combiner of the QDFA to the Grayland motel room
(AKA DX central) was 300 feet long. In any case, the Q95 does not require an isolating amplifier, which makes it even
simpler than the QDFA to put up and take down, if you don't count the complexity of the FET followers.
QH 2011 Log, Update 11/16/2011
Other stations heard at Quoddy Head 2011 could have been added to the list below, but QH 2011 was not primarily a
DXpedition. It was a test of new antennas. There are enough entries in the log now to conclude that the dual active delta
flag antenna array is superior to 1000' terminated BOG's for MW DX and the quad 95' WOG array is even better.
531 Algeria
, El Ain Beida, strong and clear, // 549, around 2100 UTC, 11−4
2
549 Algeria
, Les Trembles, strong and clear, // 531, around 2100 UTC, 11−4
585 Tunisia
, Gafsa, RTT, presumed, Arab singer accompanied by middle East music 2145 11−8
612 Morocco
, Sebaâ-Aioun, sign on with national anthem 0500 11−7, followed by brief announcement, then Qur'an
chanting
639 Czech Republic
, Ceský rozhlas 2/6, various, sign off with anthem // 954 just after 2300 11−6
648 Spain
, Granja Escuela (Badajoz), very clear, //585 0100 11−6, 648 was a difficult splatter covered frequency when I
was at Quoddy Head in October 2008 using 750 foot and 1500 foot BOG's
657 Italy
, various, underneath Spain RNE 5, // 1575 about 0300 11−8
666 Syria
, Sabbura, presumed, not // Algeria 891, bits of middle East music, can't tell if the singer is a man or woman, 2009
11−6
675 The Netherlands
, Lopik, R. Maria, religious programming, very clear around 2115 11−6, Arab talker underneath, the
Q95 really kills splatter on this frequency and lets you hear underneath the dominant signal; two days later... piano interlude
with “Radio Maria” spoken twice as part of an ID about 0300 11-8 on the DADFA which also does a very respectable job of
splatter reduction
675 Libya
, Benghazi, Radio Jamahiriya, presumed, 2202 11−8
693 United Kingdom
, various, BBC Radio 5 Live, EE talkers, every night
693 UNID
Arab chanter 0052 11−6, not Algeria
702 Monaco
, Le Col de la Madone, just after 2100 11−6 an ID in French believed to be China Radio International, arm
chair listening audio quality on the Q95, much better than in October 2008 when I was at QH
711 France
, Rennes-Thourie, France Info, there every night
747 The Netherlands
, Zeewolde (Flevoland), presumed, good just before 0300 11−8, but faded at ToH
756 Germany
, various, Deutschlandfunk, German talker, OK signal, 2224 UTC, 11−4
765 Iran
, Chahbahar, chanting // 1503 about 0100 11−6
774 Egypt
, Abis, Middle East Radio, presumed, 0040 11−6 under Spain with middle East singing
774 Egypt
, Abis, Middle East Radio, chanting about 0230 11−5, // 819
783 UNID
(haven't listened to recording yet) two, maybe three stations here, m FF talker and f FF talker, very clear at times,
generally good, probably Algeria and Nouakchott, with perhaps a third female chanting in an African language, possibly
Nigeria (Nigeria was also noted on 917, but with little or no audio)
819 Egypt
, Batrah, presumed, noted in passing 11−2 about 2000 UTC
819 Egypt
, Batrah, chanting about 0230 11−5, // 774
855 United Kingdom
, Villa Farm (Ludlow), Sunshine Radio, // 1530, EZ listening rock, about 0058 11−9
882 United Kingdom
, various, BBC Radio Wales, very strong around 1952 11−6
909 United Kingdom
, various, BBC Live 5, very strong and clear, 2235 UTC 11−4
918 Slovenija
, Ljubljiana-Domzale, coo coo clock IS about 2130 11−6 followed by "Radio Slovenija" ID, and into
American accented English news read by a woman; big het from Nigeria plus other weak signal(s) on frequency, a mess
tonight on this frequency, the Q95 hears almost too well
936 Iran
, Urumiyeh, IRIB 1 regional Azerbaidjan px, // 765 // 1503, about 0000 11/9
945 France
, Toulouse-Muret, France Info, male French talker about 2200 11−7
954 Czech Republic
, Ceský rozhlas 2/6, various, various, sign off with anthem // 639 just after 2300 11−6
963 Tunisia
, Tunis, presumed, chanting up to about 2200 11−7
972 Germany
, Hamburg, NDR Info, presumed, two English EZ listening songs, German language announcers, but faded at
3
2100 11−7 so no ID
981 Algeria
, Oulet Fayet, Alger Chaîne 1, presumed, Arabic singing with drums and string instrument(s), but not the usual
middle East style, 0330 11−8
999 Moldova
, Maiac, TWR IS about 2000 11−7
1008 The Netherlands
, Zeewolde, GrootNieuwsradio, presumed, hymn-like music, Dutch announcer, about 2000 11−8
1035 Estonia
, Tartu, Radio Eli, presumed. Severe splatter at Quoddy Head, heard every night, sometimes very strong and
clear, especially on the Q95 array, definitely IDing them has defeated me. The format(s) are sometimes music, sometimes
EZ listening rock with English language singers, sometimes music of a type I am not familiar with, occasionally in
language(s) I am not familiar with (sometimes Russian), sometimes announcers (sometimes male, sometimes female,
sometimes both alternating) talking for varying periods of time, with occasional what sounds like “hifi FM” or “hifi AM”,
and occasionally what sounds like the word “Estonia.” Sometimes the announcer(s) gave song titles and singers names in
English. Thanks to a courteous European DXer who said, “The content described precisely matches my own
observations,” and who sent me a report that the Portugal 1035 kHz transmitter was turned off while I was at Quoddy Head.
1053 United Kingdom
, various, TalkSport, “TalkSport” ID about 2100 11−7, English speaking announcer talking about
sports, het on about 1054 kHz
1062 Italy
, various, // 1575, 2019 11−6, same echo from the synchros as when I was at Quoddy Head in Ocrober 2008,
strong with fast male talker
1062 Iran
, Kerman, presumed, unusual harmony chanting by two males, about 0100 11−6
1080 Iran
, Abadan, presumed, singing chanter, about 2100 11−7
1089 United Kingdom
, various, TalkSport, // 1053 English announcer talking about sports before and after 2100, about
2100 11−7
1107 United Kingdom
, various, TalkSport, // 1053, distinctive jingle at ToH 2200 11−7
1116 Italy
, various, //1575 about 2100 11−7, fast Italian talker and occasional distinctive tinkling sound
1116 Iran
, Bandar, presumed, chanter under Italy, about 2100 11−7
1134 Croatia
, Rasinovac, Glas Hrvatske, there every night
1143 Kaliningrad
, Bolshakovo, most likely the one, R. Mayak IS, 2130 11−6
1143 Kaliningrad
, Bolshakovo, most likely the one, R. Mayak IS, 0330 11−8
1170 United Arab Emirates
, Al Dhabbaya, Radio Sawa, clear, but with IBOC hiss 2021 11−7, male Arabic crooner
1179 Romania
, various, România Actualitata, IS played over and over again like a broken record around 2015 11−7 (this
one not heard at QH in October 2008)
1188 Iran
, R. Payam, 3 note IS about 2300 UTC 11−4
1188 Germany
, Reichenbach, MDR-Info, presumed, male and female German talkers, after 0400 11−8
1206 France
, Bordeau-Nice, strong as usual every night, some fading, both high and low side carrier hets not noted when I
was here at QH in October 2008
1215 United Kingdom
, Absolute Radio, strong as usual every night, some fading, I seem to recall Spain surfaced here also
1215 Kaliningrad
, Bolshakovo, Voice of Russia World Service English ID, about 2200, 11-6
1224 Bulgaria
, Vidin, R. Bulgaria IS 1900 11−6
1224 Iran
, Abadan, weak under Bulgaria, 1900 11−6
1242 France
, weak but clear about 1930 11−2
1251 Libya
, Tripoli, presumed, Arab singer with middle East music 2003 11−6
1296 United Kingdom
, Langley Mill, “... on Twelve Ninety Six AM, this is Radio XL,” just after 2000 11-6 on the Q95
1296 Sudan
, Reiba, presumed, Arabic Qur'an chanting, 0222 UTC 11−7
4
1296 Spain
, various, COPE, 2059 UTC 11−4
1314 United Arab Emirates
, Al Dhabbaya, “Radio Farda” (sounds like Radio Fardo) by female announcer, male (Farsi?)
talkers before and after 2100 11−7
1323 Cyprus
, Zyyi, BBC World Service from about 0215 to after 0230 11-9, “BBC World Service” ID about 0230 followed
by World News Report, weak but quite clear on the DADFA
1323 Germany
, Wachenbrunn, Voice of Russia, English programming, sign on with English announcement “This is the
Voice of Russia world service” 0500 11−7
1323 Romania
, Târgu Mur, Radio Târgu Mures, Romanian national anthem began with chimes at 1956 11−7 and continued
until about 2000, under Germany all the way, but nevertheless rather clear because of the slow French talkers
1332 Czech Republic
, Ceský rozhlas 2/6, Domamil, faded up at 0256:23 with national anthem already in progress, 11−8
1341 Northern Ireland
, Lisnagarvey, ID preceded by FM frequency, “... 1341 medium wave, this is BBC Radio Ulster,”
classical music 2100 and later, some male and female English talkers
1377 France
, excellent about 1930 11−2
1377 Armenia
, Gavar, VoR IS (Pictures at an Exhibition) started about 2258:50 UTC 11−5 and was repeated
1386 Spain
, Bilbao, Euskadi Irratia, // 1476, accordian music just before 2200, 11−2
1394.850 Albania
, Fllakë, TWR IS 1918 and later 11−6 being repeated over and over like a broken record
1395 Armenia
, Yerevan or Gavar (depending on which reference you consult), Radio Kavkaz/Golos Rossii, carrier
appeared distinct from Albania 1394.850 considerably before 2130, talker which sounded Russian after Albania off about
2130, clear ID about 2230 11−4 on the dual active delta flag antenna array, not as much clear audio on the DADFA as on the
Q95 array on 11−6, but the ID at 2230 is easily as good as the 2200 ID from the Q95 on 11−6. The 11−6 reception was
spotted first on the 11−6 recording and I came back to the 11−4 recording after confirming the 11−6 reception with help
from several kind people on the RealDX site. Don't you love Perseus? Programming was quite clear at times, though not as
clear for as long periods of times as on the Q95 array.
1395 Armenia
, Yerevan or Gavar (depending on which reference you consult), Radio Kavkaz/Golos Rossii, carrier
appeared distinct from Albania 1394.850 considerably before 2130, talker which sounded Russian after Albania off about
2130, ID about 2200 11−6 which I could not make out and distinctive 5 musical notes at ToH which I could not match to
any IS found on line, reappeared later about 0100 11−7, seemingly the same distinctive 5 musical notes, until 0200, perhaps
later, quite clear around 0137, ID(?) 0143, “Radio … Radio...” (the word “Radio” twice, I could not make out much of the
rest). Thanks to Paul Logan, Dmitry Mezin, Mauno Ritola, and Bjarne Mjelde on RealDX for help with this entry. The
2200 ID is “Golos Rossii” and the consensus is that this is Armenia. The 0100 – 0200 logging is consistent with Armenia
per data on the
site. Programming was quite clear at times. Outstanding DX from the Q95 antenna array.
1395 Armenia
, Yerevan or Gavar (depending on which reference you consult), Radio Kavkaz/Golos Rossii, carrier
appeared distinct from Albania 1394.850 considerably before 2130, talker which sounded Russian after Albania off about
2130, clear “Voice of Russia” ID in English followed by the distinctive 5 musical notes about 2330 11−7 on the dual active
delta flag antenna array, not as much clear audio on the DADFA as on the Q95 array on 11−6, and the ID at 2330 not quite
as good as the 2200 ID from the Q95 on 11−6, but good enough. Programming was quite clear at times, though not as clear
for as long periods of times as on the Q95 array. Receptions of Armenia 1395 on two different nights of QH 2011 with the
dual active delta flag array should convince most people that 1000' BOG's and beverages are not needed for state of the art
MW DXing.
1395 UNID
after 2200 when American country and western songs appeared, no announcer, continuing with other English
songs to at least 2237 11−6, fading in and out, competing with and trading places with Golos Rossii (Voice of Russia),
Armenia. This is almost certainly Radio Seagull, Harlingen Harbour in The Netherlands.
1404 Romania
, Vadu Izei, România Actualităţi/Radio Sighet, national anthem, about 2000 11−7
1413 Moldova
, Grigoriopol, Russian talker, then Voice of Russia ID about 2000 11-6
1422 Algeria
, Alger, sign on with national anthem about 0400 11−8, chanting before and after
1422 Germany
, Heusweiler, classical music, and then "Deutschlandfunk" ID at 2200 11−6
5
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