NP4A the Fun Way:
3-El Full-sized on 3.5 Mhz at 160 Feet

by Jeff Briggs, K1ZM
k1zm@aol.com

Author's Note: The article which follows relates what it was like to OPERATE the 1988 CQ/CW Worldwide DX Contest from NP4A while using a 3-el full-sized yagi on 3.5 Mhz at 160 feet high. Construction details, design specifications and pictures have been reserved by prior agreement to CQ Magazine and will appear in a subsequent issue of that journal.

Background...

By now, most active contesters are aware of the new 80m Yagi that has been under construction for the past two years in the Caribbean - that being the monster "dream antenna" of Pedro Piza, Jr., NP4A. In July of 1988 the antenna was completed and in short order the initial results were in -- the new array was a veritable FLAMETHROWER! Perhaps Sant, G2PU, said it best when he was overheard to have remarked "Good God man! What are you using down there? You're the loudest station I've ever heard on 75 meters!"

Last November I was invited to visit NP4A to give the new beast a go in the CQ/CW DX Contest. Since Pedro had tried out the antenna mono 80 during the SSB test in October with good results, I knew the November test would be terrific. Naturally, I accepted and ordered my plane tickets in record time!

When I reached Pedro's QTH I was more than impressed. Perhaps what appealed to me most was the fact that here was a beam with a 145 foot reflector that by itself weighed all of 500 pounds and there wasn't an inch of sag in the whole element when viewed from over a mile away! I mean, the man knows how to build an antenna. Also, the array was perfectly aligned, all elements level and aimed directly at the horizon -- not a simple feat for something that weighs over 2500 pounds!

Even though it was late at night when I arrived at NP4A (after a very long day at work) I just had to make a few contacts to try the thing out before going to bed Thursday night. One CQ generated a pretty large European pileup and after exchanging a few quick 599+ reports, I knew the contest was going to be super -- the antenna really "talked"!!

0001Z - The Race Is On!

A bit of backgound info needs to be told first in order to put things into proper perspective. Pedro and I had discussed our expectations for the test and figured I would probably make around 2000 contacts during the monoband 80m effort. Not being a K1EA computer jock (not yet anyway), I had prepared paper logs and multiple dupe sheets for the USA, Europe and the rest of the world. I guess I am a glutton for punishment as I was fully unprepared for what hit me once the clock struck 0001Z.

I picked out a spot near the band-edge and worked a few "bubs" up until the start of the contest. A UD6 called me at 2359Z and we chatted until 0001Z so he became my first QSO in the test and a nice double multiplier to start things off on the right foot! What happened after we signed I know I won't soon forget. As I let out my first QRZ, it literally sounded as if the sky had fallen in on me. There was a pile-up of European stations AT LEAST 500 deep calling continuously occupying nearly the first 5 khz of 80m cw. As some of my friends know, I have been contesting for nearly 30 years now, know the "code" so to speak and have experienced just about everything that amateur radio contesting has to offer at one time or another -- or so I thought! But, this was something else -- just not to be believed. It is hard to put into words the feeling of utter helplessness being completely overwhelmed by a CW pileup of this size. I think I completely froze for about 30 seconds trying to figure out how to deal with what I was hearing. I finally decided to split my VFOs on the TS-940 and listen up-frequency to the top of the pile which by now was around 3508 khz. I really had no choice as the bottom of the band was where I was transmitting and I couldn't go there, even though a few Eu's were calling me below 3500 as well.

The basic plan was to pick a couple off at the top of the pile, listen for tail-enders as best I could and try to establish some kind of a rate. That may SOUND easy, but it was not. The concept worked okay for about each set of 2-3 QSOs but then turned to disaster. As soon as the Eu boys figured where I was listening, all five hundred of them shifted up frequency and then, there they all were again, calling continuously. Bedlam does not do justice to what I was hearing. So, I had to jump around back and forth all over the low-end just trying to get even two letters of a call so I could intelligently go back to someone. I must admit this was embarrassing and frustrating at the same time. And, I apologize to those who were calling. I am sure it was frustrating to be calling a 599+ sixty db-over NP4A with seemingly "no ears", but that was the way it was.

The process sort of worked and I wound up with around 100 QSOs for the first hour. It was acceptable, but the pileup's size really had done a number on my rate. A smaller pile that I could have managed more effectively would probably have yielded a rate of over 150 QSOs. My only hope was to work the boys as fast as I possibly could and pray that I could diminish their numbers quickly enough to raise my rate to a more acceptable level. Again, I must say this was the first time I have ever been humilitated by the size of a pileup - but it actually happened.

The process indeed worked and the second hour was better, somewhere around 102 q's. The third was better still and eventually rose to about 120 per hour for the next 5 hours. When I hit 0800Z I figured that I had averaged roughly 115 per hour for the first eight hours of the contest. I was delighted but thoroughly exhausted. Visions ran through my head of Chuck, K0RF, operating 40CW at KP2A the year before and cruising along at around 150 per hour, as fast as he could go, for the first seven hours. I never thought it was possible to do the same on 3.5 Mhz but indeed it was!

What is also worth noting is that I was keeping up three manual dupe sheets with a mechanical pencil while all this was going on! When the last GI's and GM's finally faded out at European sunrise around 0830Z I stood up for ten seconds, shook both arms up and down for a bit to get things flowing again and was thoroughly relieved NOT to have to deal with Europe for at least another 15 hours (Hi Hi). It had been quite a run and nearly 1100 Qs were in the log, but it was sobering indeed!

When Europe dies out on 80 CW, it is time to run the states for awhile and then start looking out to the Pacific and to JA. I worked alot of W/K's in the next hour, most of whom I could not hear at all when the beam was pointed at Europe. With Pedro's new antenna the states are 25 db down when compared to a sloper headed at W1. And, as luck would have it, the Eu sigs were all head and shoulders above the USA signals. This is important since all those Eu Qs yield 3 points and the W/K's, which usually cover up many of the lesser-equipped Eu boys, are worth only two points per QSO. This may not seem all that important but in fact it is the key to the contest from a two point North American location. In order to set a new world record on 3.5 Mhz, which was my real objective, I needed to work every Eu station that moved -- and before this contest was over I think I did. Even 10 watt wonder UJ8 stations were 559 or better at NP4A on the new antenna.

Part of the strategy on 80 of course is to work runs whenever you can and the JA sunset timeframe was the next opportunity to make some three-point hay. From Puerto Rico this is a tough shot and requires good conditions in addition to a fine antenna. Unfortunately, this was not the case on Friday night of the test. When conditions are poor the JA's come out of the southwest around 200 degrees on a side-skew path. When this happens, the JA "bubs" are puny weak - around 339 - and if a bunch start calling together, you have had it. It is impossible to get even a partial call with the echo and polar flutter accompanying the signals along with the QRM.

When conditions are good, the path shifts North after JA twilight and then signals are more solid 559-579 for the better equipped stations.This "moving North" of the path never occurred the first night and I was left with an enormous pile of JA's that I literally could barely hear. There was quite a bit of Caribbean static to boot and after working about 12 JA's in a half hour period I decided it was better to pick up some more USA Q's and hope for better conditions the second night. I managed a few choice Pacific goodies as well including KX6, KG6 and a very loud YB0ARA at KP4 sunrise. After sunrise it is still possible to work the USA for about another two hours and I milked it for all it was worth finally crashing about 1230z for some much-needed sleep. By this time my right arm was really sore from writing as fast I as possibly could all night long. Never again this way - K1EA, you will be having a new customer as soon as I can buy a PC!

The Second Night......

One of the observations made at sunset Saturday answered a question once and for all that many of us in YCCC have asked ourselves over the years. That question is whether or not it is possible to be heard in Europe on 3.5 Mhz during broad daylight at the Western-end of the path. I have often wondered if antenna gain could compensate for local European QRM at their end of the path. What happens is that we can hear the Europeans well before sunset, sometimes 599+, for nearly two hours before it is possible to get them to respond. Obviously, in this situation we are beaming into the darkness through the absorption of the "D" layer and my hope was that the extra gain of the 3-el Yagi would raise my signal level enough to get the Eu's attention sooner. Well, now I know the answer; even with an extra 8 dB of gain it is not possible. I had to wait until about 45 minutes before local sunset before the Eu boys started hearing me consistently. Oh well!

Tuning around the band at 2100Z yielded a very loud EA8XS and VK6HD long path for a nice double-multiplier (Zone 29). A few Europeans started hearing me somewhere around 2200Z. About this time I became aware of a huge European pileup all calling something I could not hear. I kept coming back to the pileup but never could figure out what was going on exactly. I was to be very pleasantly surprised the following afternoon! About 2230Z I got another European run going and again this was non-stop bedlam until 0800Z. I really did not think it was possible to work so many Eu boys on 3.5 Mhz. There were a few Russian stations that I couldn't quite pull out of the Caribbean QRN, but not many! Looking back at my dupesheet I noted later that I worked about 250 Ukraine stations, over twenty UA9's, numerous UH8, UI8 and UJ8 stations in this period. About 100 G's and DL's were in the log as well. Needless to say, the antenna was "cooking"; the rate was still around 90 for most of this period and the pileups had become manageable. I found I was able to keep up much better than the night before.

Around 0745Z I worked my first JA station and this kicked off what was to become a run of nearly 120 JA's right up until sunrise; the last JA was worked at 1111Z. This time the JA's did peak out of the NW following their sunset and I was able to take the pileup by JA call areas. I started with JA1, JA2 etc and found the JA boys were extremely disciplined throughout the entire three hour and one-half run. Taking the pile by districts limited the pile to about three stations at a time, and even though it seemed painfully slow at the time, I later figured out that I was running JA's at about 55 per hour with their signal levels averaging 449! This was both fun and challenging at the same time with QRN and polar flutter making copy really tough at times.

Sunday Evening

Sunday evening proved to be the high point of this contest. Again about 2200Z (local sunset) I came across the huge pileup of Europeans calling something I couldn't hear. There wasn't much else to do so I really tried to find out what they were calling this time. After about 10 minutes I began hearing the DX station, weak but clearly copiable. It was 3W8CW about 339-349!! I started calling with the Europeans and after about five minutes I was convinced I would never make it. I remember thinking "Jeez, even with a 'cannon' for an antenna these Eu boys must be 3 s-units louder than I am in Vietnam -- this is hopeless!" Just then I heard another station start calling me. It was not the 3W8; it was much louder, so loud that I was sure it was a Eu station. I listened and heard "NP4A, NP4A de HS0A, HS0A K". I couldn't believe it as this guy was 579. I later learned it was Fred Laun, K3ZO operating. So I quickly exchanged reports with Fred, delighted for the Zone 26. Just then the 3W8, having heard the QSO, started calling ME. I quickly exchanged reports for another multiplier and a second, back-to-back Zone 26 on 3.5 Mhz. At this point I was happier than a proverbial big in you know what -- and tuning up about a half a Khz I found Dick Norton calling CQ from SU1ER. I needed Zone 34 so I worked Dick and indeed thought I was in heaven. A minute later I found an IS0 which I also needed which became my 6th multiplier in about five minutes time. An excerpt of my log at this point looks like this:

     2207Z HS0A    Zone 26

     2209Z 3W8CW   Zone 26

     2211Z SU1ER   Zone 34

     2212Z IS0... 



     6 New Multipliers  

After all this excitement had died down, I basically ran Europe until 2400Z. My last hour of the test was an 88 hour into Europe, not bad for the 48th hour on 3.5 Mhz.

The Aftermath

When I got back to New York I had a friend at work write me a simplistic duping program for my PC-XT at the office. One night in early December I spent about five hours keying all the calls into the computer and found that I had 77 dupes out of 2333 QSOs made in the test. The final line score came out at 2256 Q's, 31 Zones, 103 Countries. I found that due to the sunspot maxima I had missed Zones 01, 13, 30, and 38. I guess there was no activity from these places this time around. Too bad, it would have been nice to have made 35 zones on 80 CW. But, all things considered, I knew I had little to complain about. It had been the thrill of a lifetime and something I'll probably remember the rest of my contest "life". Most contests in time seem to blend together after awhile -- like a blurred continuum in your mind -- but this one was SPECIAL. Final score was over 800,000 points (claimed score) for a new world record which made Pedro happy, not to mention yours truly!

I suppose that in about three years time it will be possible to generate a higher score. Certainly, one could be made from a comparable station in three point country, ie: 9Y4, PJ, P40 or, perhaps at CT3 or EA9/EA8. What was especially noteworthy though about this particular effort from NP4A was that over 1500 European stations and JA's were worked in all. This means that only about 625 W/VE Q's were made. The overall point factor from 2 point territory was about 2.71 which exceeded my wildest expectations! We figured it would be tough to make a better score from North America, even at the bottom of the sunspot cycle!

Needless to say I was amazed at the performance of Pedro's new antenna. If you were at the Antenna Forum at Dayton this year you know what an impressive antenna this thing truly is. And, don't miss the CQ article and pictures when they come out later this year. Finally, would I give this another go given the opportunity? You betcha!!!

Statistical Highlights

Ratesheet

Hour  1st Day   2nd Day



00      100        98

01      102        89

02      119        86

03      120        81

04      106        86

05      121        75

06      126        79

07      100        48

08       80        41

09       37        55

10       40        56

11       39        37

12        6         4

13        -         2

14        -         -

15        -         -

16        -         -

17        -         -

18        -         -

19        -         -

20        3         -

21       30         6

22      103        78

23       92        88



Totals 1324      1009



Grand Total 2256  

QSO Breadown

Non-European DX    71

JA                123

W/VE              628

Europeans        1434



Total            2256  

Contest QSO Rate

For 34 hours operated 66.35
For 29 significant hrs 77.06 (Less 5 hours with fewer than 10 QSOs per hour)