Bilal Isotron

When Ihe box arrived in my office last Wednesday, i remember thinking: "Even Ralph Biial couldn't fit a 40-meter anienna into a package only 33" x 6Yz" x 3". . . why, that's smaller than the boxes most model airplanes come in!"

Ralph had promised to send me the latest version of this Isotron 40, a small, versatile antenna designed for limited spaces such as apartments, condos, campers, and Ihe like where it is almost impossible, for either legal or physical reasons, to put up a lull-sized antenna, It-s also recommended. from the standpoint of size alone, to serve as an emergency, mobile, or portable antenna that can be used in motel rooms, at a disaster Site, or even bracketed !o the bumper of an automobile.

"All wefl and good," f thought, "but does 11 work?"


On Friday, after work, I took the box out of the lrunk of my car and carried it into the workshop, wondering if Td be able to get it on the air before dark. When ¡1 opened Ihe bo?, the first thing I noticed was the neat packaging job done by BHaL There were two plastic bags containing hardware—good quality, plated hardware or aluminum hardware, depending on the use. i wondered if there was enough to go around; it has been my experience in the past to be shortchanged on nuts, bolts, and washers. But not this time, as you'll see.

Each component or group of components was neatly wrapped and protected with brown paper and packaging tape. There were four pre-d^illed and bent aluminum plates, one with an S0239 UHF con. nector and a small standoff insulator already mounted on it; there was a 31" length of clear plastic tubing, partly wound with #12 insulated wire, with a nice foot-long lead and terminal soldered in place, and a piece ot clear plastic tubing about 20" long, pre-drilled with holes; there were a couple of pieces of Ludtev with holes in them, a piece of V-square aluminum tubing. and several other, smaller pieces lhat I couldn't immediately identify Nothing elaborate or fancy. either—Just plain vanilla—and good old-fashioned workmanship. I began to believe that when Ralph Bilai told you something, you had better believe il, My confidence was increasing by the moment.


The instructions include diagrams, step-by-step assembly comments, and a final tune-up procedure. After reading and rereading the instructions (something l seldom do because the drawings are clear, but in this case the antenna components seemed so different in size and shape from anything I had ever seen before that I Figured that t had better read them carefully), I began the assembly. Surprisingly, it went smoothly and without any problems at all: a new first for mei Everything fit into place and ail the holes lined up perfectly with no bending: binding. or mismatches anywhere-

Good heavens! So that's what this thing looks like! {See pholo.) I couldn't imagine anyihtng that evei looked less like an antenna! Oh. well, Ralph has been at this for over five years, so I naif better trust him. He knows more about this thing than I do.

The "far" ends of the parallel rods were pre-cfrilled to accept typicat TV-mountang hardware, and the hardware itself was included: U-bolts, washers, nuts, and plates ot good, plated quality. Even the plastic bar had a dowel inserted in one end for reinforcement—the result ot experience and cut-and-try engineering.

The instructions suggested mounting the antenna on a short length of "-diameter TV-mast rubing, and I just happened to have a five-foot length in the garage. I mounted the Isotron "antenna"' to the TV mast with the help of my XYL who held things straight while I tightened the clamps. After all was square and aligned. I did the final tightening of the hex nuts, and there it was! Clearly, something different.

The weight was negligible and the wind loading laughable. Gosh, this Ihing could fit on top of almost any chimney bracket, on a mast alongside a trailer, or even in the shack tn the middle oi the floor! Yep, that's what I did. I happened to have a military-surplus wooden tripod that had been used to mount a transit. The short length of TV mast exactly fit into the central collar, so I set it up in the shack (read spare bedroom) between the beds. A ten-foot piece of RG-3/U was enough to reach the operating desk and B&W coaxial switch mounted there.

Tune-lip and Operation

Here is where things usually begin to go very wrong, with my usual luck, and I had little confidence lhat this ugly duckling would ever be a swan in spite of Ralph Bilal's confidence. Nevertheless, only 45 minutes had elapsed between opening the box and carrying the contraption to my shack. . .sort of a new record for me. Tnere it sal on its tripod, daring me to fire up the rig and see what would happen. Okay, here goes.

Wow: signals—and quite loud. too! Pulling the rig on the lowest possible output power, just enough to get a vswr reading, I was astonished to get a reading of below 2:1, and by careful adjustment of the small, parallel "tuning" plates attached to the upper and lower "diamond" píates, I was able to get a reading of below 1.5:1 at 7025 kHz, That is belter than the standard trapped vertical I had been using was able to give me, I switched back and forth between the vertical (roof mounted with 12 radlals) and the isotron 40. noticing that Ihe QRN was appreciably lower on ihe Biial antenna, whereas the received signals were not much if any different in strength. Once again, I was Impressed with this little critter. Now if It would only transmit, I'd be happy.

Proof of the Pudding

Rather than timidly call a CQt I decided to be brave and answer someone else. After all, if he didn't come back to me if wouldn't be my fault —or as disappointing — as if f had called and been found wanting. Okay, let's see. . .here's a good strong signal at 7031 kHz.. KU1G. . nice CW., . there, he's signing, . .

KU1G KU7G< de W1XU, W1XU, K. WlXUde KU1G; R, Rt Tnx cali OM; ur sigs 599, 599 hr_in Monroe, CT; name is John. Hw copy? AR. W7XU de KU1G, K.

Wow! 599 in Connecticut! Well, maybe lhat's just an exception. Let's finish here with John and try another.

At 0020Z [twenty after seven, local timo) I heard WX4L caiting CQ. A quick shout and he came back: 559 in Gaffney, South Carolina. Name is Ed. Well, that is more reasonable, I thought, but still, all the way to South Carolina on an indoor 'lump1' ain;t too shabhy!

Next, I called Steve K4CXJ in Nashville, Tennessee, and we compared antennas. The trapped vertical gave me a 569 with QSB and the Bilal Isotron gave me a 569 with no QSBt The band wasn't great, but It was active.

Along about twenty before 9 I heard Bill K2SVC in Ithaca, New York, and he gave mea 599 with some QSB. A quick comparison showed the outdoor vertical at 39

Antenas Isotron
The (sotron 40,

and ihe indoor 'Isotron at 56. Not bad, I'd settle for that any day.

After signing with Bil^ I worked Jim KXSE In Highland. Michigan. Jim said I was 599 there and claimed very little if any difference between the veriical and the Isotron, It was obvious that the band was improving and that the mid-range stations were skipping in loudly.

1 wonder if I ought to try a "local" to see what happens, I thought. There was Paul KB1 MJ^BS with his brand-new Extra-class ticket on 7024 kHz. Giving Paul a quick caEFh F got a 589 from him. He was down a bit, F thought, but the 569 J gave him was still a good report. When ne told me he was running 20 Watts to a home-brew sta* tion (nor just a transmitter), I perked up. It seems that Paul actually loves to build gear, and his receiver Is about 9 months along in development, . .with a few more to go until he is satisfied. The keying was very nice, home-brew, of course, and Paul said ne made the paddles, too!

The transmitter was a combined soiid-state vfo with a tube final. Nice, t suggested to Paul that when his siation was completed to his satisfaction, maybe he ought to write it up for a magazine.. .hint, hint! Let's hope he does,

Well, it was getting late; maybe a couple more and then to bed. Tuning around, I discovered Frank VE2GG In Dorval. Quebec. on 7021 kHz. He came right back to my call: "599, QMr,: He was about a 589 at my station. Comparing antennas, Frank mentioned to me that the Isotron was S9 + 10 dB1 whereas the outside antenna was only S9 + 5 dBf Here, the Isotron actually put out a better signal than the- regular antennai Probably skip angle, etc., but who cares? The performance of the Isotron 40 is just plain phenomenaE.

My last QSG of the evening was with Chuck N8FNZ in Detroit. He gave me a 5&9 and 1 gave him a 579 at 0354Z, six minutes before eleven o'clock local time. Chuck was using his new Icom 751 and a dipole, sloping toward Ihe east.

Well, time for hitting the sack soon, so I signed with him after a pleasanl rag-chew and switched off the rig. Well satisfied with the evening's work, I decided to try SSB on Saturday morning. After all. with 75 Watts output, CW is a lot easier to cut the mustard than phone, 1 realized, so phone would be the final proof I needed to see if the Isotron was really an antenna.

On Saturday mommg at 9:50 local time, I heard W3DWI calling CO.. His signal was loud arid I wanted to call him. but I had nol changed Ihe setting of the antenna to adjust it for lowest vswr up here on phone. Nevertheless, I decided, what the heck; I'll just call anyway: no harm if he doesn't hear me. A short two-by-two, and Ed In Chambersburg. Pennsylvania, came right back with a 5/7 report. . .very little QSB. . . nice steady signal. We exchanged the usual information and had a pleasant half-hour chat right in the midst of the Saturday morning QRM.

When the QSB took me almost out, I switched over to the outside antenna and was able to finish the QSO. So—we found out that under poor conditions, the outside BIG antenna is a bit belter than the small (tiny) indoor one. Well, what's so surprising about that? That's what one would expect . .but J was still very satisfied with the Isotron 40. Ralph hadn't lied to me yet; he hadn't overstated his performance figures; the antenna worked just as he said il would. Not only lhat. I firmly believe that if the Isotron 40 were placed at the same height as my vertical and outdoors, it would work equally well! that's a lot to say, but I think it is a true statement .. . and I'm going to prove It soon.

Later, after a long weekend of testing the antenna (during which time, nearly 1Q0 slat tens were worked on phone and GW). a pattern became quite clear Under good Conditions [he isotron 40 nearly equalled the much higher outdoor vertical Under poor conditons. il was nearly three 5-umts poorer On the average, the isotron was only one to two 5 units down compared with the vertical

It will be desirable to mount the antenna outdoors at 'he same height as the ver. ncal further comparisons I strongly belie-e based on tests so far, that it could be almost as effective as the vertical

Gtner stations contacted in the US were K4JE l&aS)j, W4LRD (579*, and W2JUF During Ihe European Fi&ld Day, we worked Ihe following foreign stations using ihe isotron 40: GN7AR/P (589j. G3WKX tmu DLflET (559), DLOOS (379jr DLBAU (55fl). G4GXK (579)h DKCTU (599) DF&CN (599), PI4RT? (599)h and GM3USL (599) Later. I heard NQ6E in San Francisco, and Bob gave me a 569. Of course everyone knows that all contest reports are not exact. but at least Ihe antenna can work DX withoul a terrific disadvantage.

Many times my signal would be 58 on the fliiof antenna and S9on the vertical. In only on* case, reported before, was the isotror better than the vertical

Almost every station contacted In the US and! Canada was very interested in knowing more about the Isotron. One operator even said he going to buy the BO-meter veiSion after hearing whai the meter version cous do. So, there you have it. fans Try one for yourself and see what you thJnk.

Th«ry of Operation

The Isotron antennas may be capacitive hais on a loading coil , because Lhai's what th^y appear to De electrically. However theri ¿i large radiating surface (according to Ralph) that wouid seem to makt ihe l&utfon antennas the equlvalGni in surface area to full size antennas, This does not imply lhai the capture area" of the laoiron is Ihe equivalent of Ihe larger antenna, however. in spite of the small 5170 131" > 18" X I2'h, approximately), It appears lo be radiating quite efficiently— something mat I had not thought possible with merely a loading coil wlUii capaoiy hat as a radiator of rf energy,

Thf"1 claimed bandwrdth between 2:1 vswr limns is 200 kHz. according to Ralph's measurements. f was able lo verity this approximately by swinging be-lween roughly 7050 and 7250 kl-ta without retumng Ihe antenna. However, for really crideai work, it would be best to retune tne antenna when moving from the low end CW portion to me high end SSB portion of the band

R^iph mentions the fact that it is necessary to tie -ery careful in adjusting. and tuning The antenna because the surround ings can affect its Impedance draslically. He gives some good counsel in the instructions about this, and several recommendations to follow in case tuning up is a problem. An rf noise bridge or similar do vice to help tuning is strongly recofh mended when setting up the fsohon lor best performance.

Olher Antennas by Bilal

Ralph Bilai can furnish a 160-meier Iso* tron an 00-meter /erston, and a 20-meter version also, t would like to say (hat Ihe one that looks most interesting to mo is ■he combination 60.r40 Isotron — actually iwo antennas tuned to the hands, mounl-ed back to-back on a single mast, and fed with ' wo separate feed lines Uvmg as t do m □ home that rests in a small clearing in ihe woods, that would really solve my antenna problem, I have used a chimney mount tor several different verticals and small beams1 so I think It would be very practical, simple, and nearly ¡deal In my location to solve the problem with Ihe Iso tron system.


I really like the isotron 40 and am going to be very interested in trying out the other versions to see «f they perform as well on their respective bands as this one does on 40 meters Ceitamly the price ts reasonable considering what you get: the 160-meter version that stands only 5 feet high and weighs only 12 pounds (smaller than mosi two-meter beams} tor S149 95 plus Si- opfng. the 0A-meter *e-'sipn at 4"feet and 7 pounds at $63.96; the *0-meler at 31 nches and 4 pounds for $5296, and tht 2frmeter Isotron, on special sale at 95. measuring only 21 inches and weighing In at a mere 3 pounds. Finally the l;5-metef version at mches and 2 pounds, goes 'Or S32.&5 Ail of these must have shipping cos is added, varying between S3.50 and

The 80/40 Special" Isotron comes for only Si 10 plus $8.50 shipping cosi and there are also IOmeter and l&meier ver sions lor hams, as well as an 11 meter version for CB

For your own Isotron, whatever It may bo, call or writs to the Bttat Company, 2, Eucha OK 74342; {918^2534094, Tell Ralph thai 73 sent you, with a strong recommendation. Reader Service number 477.

Jim Gray W1XU 73 Staff


Nothing thai simple will ever work.

Thai was my first thought on viewing tne Barker & Williamson AP-tO Portable Antenna I had seen ads In ham pubhea-tions from B & W but had aiways just glanced them.

Now. however, for the lirst t-me in 15 years i was faced with Uvmg m an apartment. I had cha^iged jobs and moved from Ohio to Wisconsin, and i discovered thai our new apartment complex allowed absolutely no outdoor antennas

My father IKSMC? a vele*an DXef of many seasons, had purchased ihe B ^ V* antenna for me as a Christmas ptesent He did his best to convince me (hat this was better than no antenna ai all I docltf* ed to give it a try. II was a eMher lhai or lace the unpleasant withdrawal symptoms associated with lack of exposure to Morse code.

The antenna had arrived In a neat little box with all of the parts inside. The parts Included a 22 Va-inch whip which lele scoped to 57 inches, coils lot 10 meters through 40 meters (including 30 meters.-, a wire counterpoise coax. and issortefl screws and bolts. (We've heard that th? AP W win load on 2 and 6 meters without additional hardware — Fd

Also included was a very clearly written instruction booklet. Then agam, the an lenna was so simple that the Instruction booklet necessarily was -orv basic and weir written.

Assembly time ^.as ^tou- 5 minutes and quired on I. a screwdriver and a e^-i-cl phers. To a seasoned DXer and thrs sec-ond-genefation ham. it swMd too good to be true.

Not content to wait until l returned id Wisconsin, put the ani^nna on the air at my father's otd homestead In Ohio. Since the weather was a little nasty nutside, we decided to clamp the antenna to a wooden table in the ham Ihack.

To make a long story short, the anienna worked, It's true we dldh't work any e*OtiC couniry on the first iry, bui our CQ calls produced solid contacts on 40 meters with hams In several easi-coast states.

Since both of us use antenna tuners tor all of our antennas, the 0 & W Indoor whip was run through an MFJ tuner with 1000 Watt capacity. The swr was virtually a flat 1,1:1.

Upon arriving back in Wisconsin, I began to have second thoughts ¿tbout the antenna loading up properly with my Tri ton 4. After atl. thai was a fugged antenna tuner we d used m Ohio. However, my wor ries evaporated when i tuned the little whip attached to a *ooden dresser m the bedroom with my DenTron Jr Monitor tuner Swr could be ad usted down to 1 - * throughout the CW portion of the 40-meter band I called CQ and worked stations trom Colorado io New York tnai first evening

Summoning up ail of my courage several evenings t^ie: I attached the 20-meter con The swr on thjs band couldi be adjusted to M i. arid I worked staiions from California to Npw Hampshire

Of course, I was very pleated and surprised by this kind of p^rtofmance irom a lime indoor whip, In addition, I telt conti-dent this little 0 4 W producl would keep me on the air even in the -ipariment-coiTh plex environment,

Needless to say, thefte some compromises and shortcomings one laces up to when using ihis kind or antenna You can't put out a booming, dominating DX signal, and you don 1 always get 599 siQ nal reports, In addition. I have not trted the whip on SSQ because \ work too^ CW I'm sure the results on voice transmissions would be disappointing with all of those i4tW [and 5-kW, loo, t suspect) sig nais on the air

Working with this antenna on CW is very simitar io working QRP it takes a little more effort to near the incoming signals and a little pal Fence when iransmit hng. too. However, the ptool is m ihe pudding. and the B & W whip has p/oved it can keep me on the air. Unless the bands are totally quiet, I can QSQ just about any lime I want to.

For example,) have worked 30 states on the 40-meter band, including California Oregon. Utah, and Maine While signal reports are not always good the tact still re mains that hams in (hose places actually heard me well enough toQSL.

The 20-meter band has been even better, and I've actually worked <i tittle DX. i have QSL cards from Haiti. France, and the Virgin Islands. I Ivjvl? many more cards from all over the United Stntps.

While I'm not saying the S & W model AP-10 antenna should be considered as a primary station radiator when better gear can be installed I am saying tnai it apparently does Ihe job il was designed to do It keeps hams in my stluation on Ihe air. I'm grateful, because I'd hate to face Those horrible symptoms of withdraw; brought on by the lack of exposure io f/o^se code.

For further detatls. contact barker i Williamson 10 Cana? Street. Brtstoi PA 19007

Rick Cochran WBSULZrt Kenosha Wl


Hart yOiJ recently purchased a new product lhai has been viewed m 73" ;t >ouna*e. writeandtem us what >gj. thmk atwui n 73 win pufcu^i- your cwr menis so .ou tan share ihem &i 3thtr hiirns. js part of our continu^g effort in bring you the cest m new product information artj reviews Send your thoughts la Hevre-w Editor. 73 ¿maretr/ flitfio'i Technic*} Journal Peterborough Nh 03-50

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