The AM PRESS/EXCHANGE
ISSUE NO. 75                    September, 1989


Send A Message To The League!

Last month, we outlined a plan of action for a unified effort to petition the FCC to follow through on its stated promise to reconsider the AM power issue before the scheduled power reduction for AM goes into effect next June.

Our first step is to attempt to get some kind of ARRL support. Headquarters officials have repeatedly denied any anti-AM bias and claim to be sympathetic to our cause, but we are reminded that it is the Board of Directors that determines ARRL policy. In the past, Directors have claimed to have heard very little from members in their Divisions in support of AM, and therefore have felt that this issue is of little importance. In addition, we have to make a lot of noise, because we have to compete with other issues for League officials' attention. They have recently been preoccupied with the 220 mhz situation, no-code, etc.

All AMers who are League members are urgently requested to write to your Division Director and ask for League support in the AM power issue. Letters should not be negative, hostile or overly critical of the League, but firm, positive and based on clear logical reasoning. Letters badmouthing the "slop buckets", "rice boxes" and "appliance operators" will surely backfire, since chances are overwhelming that your Director operates SSB with imported commercially built equipment, and does not own a homebrew transmitter.

In this article we have included a sample letter to help give our readers some ideas. It is a copy of an actual letter recently sent to the Delta Division Director. For maximum effectiveness, read the sample letter, think about the issues involved, and compose your own letter in your own words. If you lack the time or inclination to compose your own message from scratch, you may closely borrow from this sample, but at least change some of the wording, or better still, think of something that was left out and include that in your letter. Individualize your message as much as you can; don't expect a bundle of identically worded "form letters" to be taken very seriously by the Divison Directors or other League officials.

To find out who your Division Director is, look on page 8 of any recent issue of QST. Each Division is listed by state or geographical region. Once you have determined your Division, you will find the name, address and phone number of the Director and the Vice Director listed to the left.

Just as this issue was going to press, it was learned that Directors and Vice-Directors are up for election in six Divisions. Ballots have already been mailed to members, and must be returned by noon, November 20. This gives the AM community an excellent opportunity to bring up this issue not only to present Directors, but also to the candidates for election. It will be the newly elected Directors who will attend the January Board Meeting where major ARRL policy decisions will be made.

According to one candidate, in the last Delta Division election only about 1900 out of a possible 7500 eligible members voted - about 25 per cent. Because of low participation in these elections, an active AM community could have an impact - possibly deciding the outcome of a close race! Drop these candidates a line, or Xerox a copy of the letter you are sending your present Director, and let them know you plan to vote, and that you will decide after hearing from all the candidates concerning this issue. The names, addresses and callsigns of all candidates up for election are listed at the end of this article.

(Web editor’s note: addresses and phone numbers have been removed; this article is from 1989.)



Sample Letter To ARRL Division Director



Joel M. Harrison
(Callsign and address redacted)


Dear Mr. Harrison:

I recently attended the forum presented by Dave Sumner at the Huntsville Alabama hamfest. One of the points Mr. Sumner made clear was his assurance that the League is opposed to any further loss of existing privileges presently enjoyed by amateurs. I am writing to remind you that, in addition to the highly publicized loss of 220-222 mhz, still another loss of existing amateur privileges is scheduled by the FCC to take effect in less than a year.

The amateur radio power limit was changed in July, 1983, under Docket 82-624, from the longstanding 1000 watts input to the final, to 1500 watts p.e.p. output from the transmitter. Since the peak-to-average power ratio differs widely for the various modes of emission permitted under Part 97, the actual power limit was substantially changed for most of the modes used by amateurs.

The maximum operating power for SSB phone was essentially unchanged, while the limit for CW, FM and certain other modes was approximately doubled. However, the power limit for AM phone (A3E emission), because of a quirk in the mathematics of modulation theory, was reduced to one-half the power level permitted under the old rules. The FCC realized this was in reality a loss of amateur privileges, so in order to reduce the "immediate impact" of the ruling, a "grandfather clause" was included in §97.313 (b) to allow AM phone to operate under the original power standard until June 2, 1990.

In Paragraph 6 of the Report and Order of Docket 82-624, the FCC acknowledged that the most significant concern expressed in the comments was the effect the proposal would have on AM operations, and committed itself to review this matter before the power reduction actually goes into effect. "...We, therefore, have decided to limit the grandfather provisions to a period ending June 1, 1990. If it appears there is any justification to do so, we will reconsider the matter at that time."

Since 1983, we have seen a substantial increase in the popularity of AM, as rendered evident not only by AM activity heard daily on specific portions of the 160-metre and HF bands where most AM operators voluntarily confine their operations, but also by the fact that most multi-mode amateur transceivers on today's market include AM transmit capability. The fact that there is substantial interest in this mode, and the fact that the stated purpose of the FCC's power rule proceeding (a safe and unambiguous measurement of transmitter power level) can be served without taking away any existing privileges or making any amateur equipment obsolete, constitute sufficient justification for the FCC to reconsider this matter before next June.

As a longtime AM phone enthusiast, I am asking for the League's help in persuading the FCC to honor its commitment and rescind this unfair power limit reduction for which AM has arbitrarily been singled out. My suggestion is that the League work up an iron clad technical definition paragraph to replace the existing §97.313(b) grandfather clause", and prepare a well-thought-out rulemaking petition to FCC in time for consideration before June, 1990. Possible approaches include (a) making the existing grandfather clause permanent, (b) defining the output power for A3E in terms of carrier output rather than p.e.p., or (c) determining an appropriate p.e.p. output limit for A3E that would be approximately equivalent to the maximum legally attainable at present under the grandfather provision.

I wish to re-emphasize that AM operators are not asking for a "power advantage" over other modes, or special privileges of any kind. We are merely seeking to retain privileges we enjoy at the present time, which have existed for over seven decades.

The FCC argues that the 3 dB power reduction for AM would be "insignificant in terms of actual communications effectiveness." Experience has shown this not to be true, particularly on 160 metres where much of the AM activity takes place. High summer static levels and man-made electrical noise plague this band, and every available dB of signal often counts in overcoming the noisy conditions that prevail. Also of concern would be the expense of modifying existing 1000-watt transmitters to comply with the new regulation. This could require replacement of the costly plate transformer and/or extensive alteration of the RF output and modulator circuitry.

I am aware that the Communications Act requires the use of minimum power necessary to maintain desired communications. This applies to all modes in precisely the same way, and has no special application to AM. Despite the well-known communications effectiveness of CW, the CW power limit was at least doubled under this preceding. If this substantial power increase for CW could be reconciled with the minimum-power rule, then merely maintaining the existing power limit for AM would not be inconsistent with the same requirement.

I am certain I am speaking for many AM operators who are also League members, when I urge the League to actively attempt to dissuade the Commission from implementing an arbitrary reduction in amateur privileges, which cannot be shown to serve the public interest, or the interests of amateur radio, in any way whatever.

Can we count on your support in this matter?


Cordial 73,

(signed) Donald Chester, K4KYV


cc:    Vice Director Joseph A. Butler
         Dave Sumner

         The AM Press/Exchange



Candidates For ARRL Director and Vice Director Elections

The ARRL Elections Committee has completed its examination of nominating petitions for Director and Vice Director for two year terms of office beginning January 1, 1990. Ballots were ordered mailed to full members in six Divisions, as follows. For the convenience of readers who wish to contact these candidates, their names, callsigns and mailing addresses are listed below. (Addresses redacted)

ATLANTIC DIVISION
For Director:
Hugh A. Turnbull, W3ABC
Robert B. Weinstock, KN1K

For Vice Director:
Kay C. Craigie, KC3LM
James M. Mosley, W2BCH


DAKOTA DIVISION
For Director:
Richard P. Clem, W0IS
George E. Frederickson, KC0T
Howard B. Mark, W0OZC


DELTA DIVISION
For Director:
Arthur P. Kay, W5APX
Joel M. Harrison, WB5IGF

For Vice Director:
James A. Amundson, W5TRD
Henry R. Leggette, WD4Q
John M. Wondergem, K5KR


GREAT LAKES DIVISION
For Director:
Leonard M. Nathanson, W8RC
Allan L. Severson, AB8P


MIDWEST DIVISION
For Director:
Paul Grauer, W0FIR
Robert S. McCaffrey, K0CY

For Vice Director:
Lyndell C. Miller, WA0KUH
Laurence S. Staples, W0AIB


SOUTHEASTERN DIVISION
For Vice Director:
Evelyn D. Gauzens, W4WYR
Alan H. Page, KE4WO



open forum


Editor, AM Press/Exchange:

Attached is a copy of the petition I will be circulating several copies of within the Rocky Mountain Division. While there are probably numerous ways to state the same thing, my point is that AM operators have been shafted by the Commission without a word of protest by the League. I want EVERY Director to feel some heat before the next board meeting, and, while not replacing individual letters of concern, a petition is probably the easiest and quickest way for the average amateur to participate. I suggest that someone from each of as many divisions as possible take it upon himself (i.e.--volunteer his time) to handle the responsibilities within their particular division, and forward copies of the signed petitions to their Director. Think you ..... or someone else could coordinate things on a division by division basis?? I can be reached by mail or at (phone number redacted).

Best Regards,

(signed) Bill, KD0HG


PETITION FOR URGENT ACTION BY THE AMERICAN RADIO RELAY LEAGUE


To: ________________________ Director, ARRL _______________________ Division


The FCC has recently mandated a 50% reduction in the maximum power allowed by Amateur stations utilizing double sideband with carrier (AM radiotelephone) emissions, effective on June 2, 1990. This is yet another in a recent series of FCC actions, generated by Washington bureaucrats, that have taken away or restricted Amateur frequencies and other formerly held privileges. The League has not taken any action on behalf of the Amateur community on this issue.

We, the undersigned, request that the AM President and Board of Directors demonstrate their commitment to representing ALL Radio Amateurs by directing the League's Legal Counsel to take whatever actions are required before the FCC or other governmental agencies to restore the AM radiotelephone power limit to 1 Kilowatt DC input on a permanent basis.


SIGNATURE                                  NAME (PRINTED)                                        CALLSIGN
 





(MAKE FULL PAGE OF LINES ON LONG SHEET)



Please mail or pass along to any other interested amateurs for their signature. When full, make copies. Send original to your Division Director, and copies to your Vice Director and Section Manager. Names and addresses are printed on page 8 of any recent QST. -Editor



Editor, AM Press/Exchange:

The concern regarding the AM power reduction in the August 1989 issue has a direct legal bearing on my 1965 Cadillac, a favorite of the five business and family cars. When my brother, an attorney, was asked about the lack of smog control and its great gas consumption, I was told Congress can pass no ex-post-facto law; the Constitution forbids it. The KW rigs from Collins, Johnson, and, likely, homebrew KW's would seem to fall under the same protection, and FCC and members of Congress should be told.

Secondly, Congress is worried about the deficit in foreign trade. SSB sees the majority of purchases come from the far East. Further this mode has seen a demise of most of our well known American electronic industries. FCC and Congress should be reminded of this.

Thirdly, home construction and experimentation was a great inducement into radio for most of us. SSB rigs are hard to repair, and the "appliance status" likely is boring and costly for the younger generation. Rick is correct about the magical glow of mercury vapor rectifiers.

Finally, the summer noise on 75 has driven many to 20. 20 is so erratic of late that most don't know what goes on, and give up in disgust. Would it be best for the "rock-bound" boys to use 14,286 KC and those with VFO's to use, say, 14,280 KC. The "broad window" might have both favorable and unfavorable results, yet quite legal and self asserting.

Chad Johnson, W5DBA



Editor, AM Press/Exchange:

It seems to me that too many people gather on 14.285.   Most of the time is spent waiting your turn, or listening to see if someone is in there making a transmission.  Most of us should make contact with the people we can hear, and move off to another freq.  This will keep a lot of us from hanging on forever to get a turn.  Also, by spreading out, more people will become more aware of A.M.  Also, we need to drag our feet after a transmission, and listen for breakers.  I hear many who break but are passed up because no one takes the time to listen.  Also, if everyone was to go off and make an A.M. transmission with some SSB stations, more SSB people will also become interested.  I have done this in the past.  These people (most) are glad to see A.M. back again.  Now these SSBers are wanting to fire up their old A.M. gear.  What better way to get the new and old timers into A.M.   Now that we are on a roll, let's keep it going.  Let's not forget about the newcomers.  So please listen up between transmissions, and spread out on 20 meters.  The more who hear us, the more who will know about us.

73, Marty, WB2FOU/5



MODULATION MONITOR AND CARRIER SHIFT METER
JOHN MARTIN  W4KYL

I came across the following two circuits in a couple of old magazines, and I thought I would share them with the AM gang. I have not tried them myself, but I see no reason for any problems.

Circuit #1 is the Sylvania Mod-Meter of the early fifties. The input is link coupled to the final tank and with ganged switch S1 in the RF position, the 100uuf cap is tuned for any desired indication on the meter. This reading will not change unless carrier shift is present, i.e., it will not show fm-ing, drift, etc. With S1 in the AF position, the meter indicates modulation. Calibration of percentage can be done with a modulated RF generator and scope. S2 allows the positive or negative peaks to be indicated.

Circuit #2 eliminates the potentially dangerous close coupling to the final tank.  However, carrier shift indication is not included. This circuit operates on the principle that for any modulation percentage, there is a corresponding ratio between the carrier and envelope amplitudes. At 100 percent modulation, both amplitudes are equal. Calibration begins with connecting a 100 percent modulated RF generator to the ant input. With the proper coil inserted for the frequency in use, tune C2 for a peak reading on M1. Next, adjust C1 for full scale deflection of M1.  Finally, adjust R1 for full scale deflection of M2. Make no further adjustments to R1. Make additional checks at 90 percent, 80 percent, etc. At each level, readjust C1, if necessary, for full scale deflection of M1, and note the reading of M2. After calibration, a suitable table or graph can be drawn.

Please feel free to substitute newer components for the CK722 and the copper oxide rectifier.


COIL TABLE

Coil A
1.8 - 4 mc
57 turns No. 32 enameled wire closewound on 1-inch-diameter plug-in form. Tap 28th turn from ground end.
Coil B
3.8 - 8.6 mc
25 turns No. 26 enameled wire on 1-inch-diameter plug-in form. Space to winding length of 1/2 inch. Tap 12th turn from ground end.
Coil C
8 - 18 mc
12 turns No. 22 enameled wire on 1-inch-diameter plug-in form. Space to winding length of 1/2 inch. Tap 6th turn from ground end.
Coil D
15 - 34 mc
5-1/2 turns No. 22 enameled wire on 1-inch-diameter plug-in form. Space to winding length of 1/4 inch. Tap 1-1/2 turns from ground end.
Coil E
30 - 68 mc
2-1/2 turns No. 22 enameled wire on 1-inch-diameter plug-in form. Space to winding length of 1/4 inch. Tap 1-1/2 turns from ground end.



Multi-wire Lines and Matching Sections
By CARL J. MADSEN, W1ZB
Radio Engineer,
Westinghouse Electric & Manufacturing Co.,
Chicopee Falls, Mass.

From RADIO, April, 1937

Many of our amateur antenna systems and coupling circuits require radio frequency transmission lines, either as impedance matching transformers or as a connecting medium between the transmitter and the antenna system, or both.     

During a problem of the latter type, I found that I needed a line some thirty odd feet long, with a surge impedance of 200 ohms. Checking all the usual two-wire transmission line constants, I found that I needed two 1/4 inch tubes, separated by approximately an inch. Trying to hang a line of this type from the middle of a 66 ft. span of wire 45 feet in the air didn't appear to be very practical, physically. A concentric tubing line was equally impractical.  Smaller size conductor could have been used with closer spacing, but the voltages involved dictated a design with at least one inch between conductors, especially for outdoor operation.

After considerable investigation through old issues of QST and RADIO, no additional information was uncovered which might be available to amateurs. I did find the curves shown in figure 1 in technical data files of the W. E. & M. Co. The 200 ohm line problem then became very simple. A four-wire line using no. 16 wire (.060" dia.) figures out to have a separation of 1.5 inches (.03 x 50). Using 2-1/4 inch dia. celluloid rings (obtained in the 5 & 10c store) and drilling four holes slightly larger than the wire, equidistant around the ring, a light spacer of low loss is obtained, suitable for amateur application (see page 49--RADIO, Jan., 1937 for two-wire line). These can be threaded on the line, placing them on the wires near the ends, and then stretching the wires tight and sliding the spacers to the desired position. They can be cemented in place with DuPont household cement. At least two applications, and preferably three, separated by several hours, will hold the wires nicely.

Such a transmission line is flexible, and must be used under slight tension to keep the wires from twisting. Spacers should be placed approximately every two feet. The conductors of like polarity are connected together at the ends of the line, making it easy to connect to the antenna system or the usual 400-600 ohm transmission line as in the "Johnson-Q" system. The 4-wire line takes the place of the "Q bars", making a lighter matching section.

The chart in figure 1 also gives the surge impedance for several other groupings that give lower impedances than the two- or four-wire combinations. "D" is the separation of conductors, "R" is the wire radius. The construction of these multiwire combinations becomes increasingly difficult as the number of wires is increased; so unless you have lots of patience and mechanical skill, it is advisable to use the simple grouping combinations of six or less conductors.

This type of line can be used in the Collins "Multi-band" antenna system, or any application where a low-impedance line is required, at considerably lower cost and with less radiation loss.



W8ZO Estate
By Donald Chester, K4KYV

The estate of Charles A. Gault, W8ZO, Ypsilanti, MI is now on the market. Charlie's outstanding signal appeared regularly on 1992 khz in recent years, until his passing a little over a year ago. His station consisted of numerous homebrew plate-modulated transmitters, but his signal on 160 was largely attributed to his antenna system, which consisted of wire antennas strung between two base-insulated, self supported 120-plus feet tall towers, which are equipped with substantial work platforms at the top. Because of unbearable real estate taxes, Charlie's heir has reluctantly decided to put the property on the market, and all radio equipment, including the towers, must go. In hopes of finding good homes for all this equipment, AM P/X editor and publisher Don Chester, K4KYV, traveled to Ypsilanti the weekend of the Cincinnati hamfest, checked out the equipment, and took the photos for this article.

There are seven six-foot high homebrew transmitters, including at least two one-kilowatt plate modulated units. In addition, there is a collection of transmitting tubes still in boxes, numerous components such as transmitting capacitors, tank coils, variable condensers, meters, modulation transformers, workshop tools and equipment, books and magazines.

Charlie had been in radio since the 1920's, and those who know him say he never threw anything away. The collection includes many items dating back to the 20's and 30's; antique wireless buffs take note. Included in the magazine collection are QST's from 1922 through the present, in varying condition, scattered about and possibly missing some issues. There is also what appears to be a fairly complete collection of the pre-WWII west coast publication RADIO dating from 1936. There are also CQ magazines from 1945. The transmitters shown in the photographs are as follows.

Fig. 1: (right) pair of pushpull 250TH's, modulated by another pair of 250TH's, 1KW, with plug-in coils for 20 metres, in double rack. (Left, in the same photo): Another transmitter with 20 mtr. coils, in single rack, with pushpull T-55's modulated by 838's.

Fig. 2: Pair of 304TH's or TL's in pushpull, modulated by a pair of 250TH's, with 80 mtr. plug-in coils.

Fig. 3: 160 mtr. transmitter, looks like single 8005, modulated by a pair of T-55's. This is apparently the rig Charlie used crystal controlled on 1992 khz. The power rating is probably about 200 watts input. The metal cabinet is painted with antique style black wrinkle, with a hammered texture not seen on more recent wrinkle finishes.

Fig. 4: Antique 160 mtr. transmitter. 203-A's in the final modulated by a pair of 805's.  Note the style of the dials. The cabinet is metal, except for the front panel, which is entirely made of bakelite! Most of the meters are old-style Jewells.

All transmitters are built on casters, making them easily moveable. The large plate modulated rigs use the RCA 1:1 5500-ohm modulation transformers so commonly seen in post WWII homebrew AM transmitters. Not shown in the photographs are two more six-foot racks. One is a transmitter with power supply and a single 851 in the final. There is no plate modulator (CW-only or grid-modulated rig?). Another similar rack holds a low power (807 class) AM transmitter that is missing parts.

There is a 75A4 receiver in apparently good condition, but because of its location in a custom made console, it could not easily be inspected internally to determine what mechanical filters were installed or its operating condition.

Antique buffs may be particularly interested in a genuine motor-generator, apparently from the 1920's, which converts 120 volts AC to 1500 volts DC at 165 mills. This is a real classic with brass nameplates. It consists of a separate motor and generator mounted on a steel frame with the shafts coupled together mechanically.

The owner has decided that most of this equipment will be sold. While he is not giving away his father's equipment, he is not insisting on top dollar, and will accept realistic offers for any or all, preferably from persons interested in putting it to use, not scrapping it.



AN AM ANTENNA FOR REACHING THE OTHER HALF OF THE WORLD EASILY
Copyrighted, 1989
by George A. H. Bonadio, W2WLR
Watertown, NY 13601-3829

Part 8

There is a simple OTHER HALF OF THE WORLD antenna, upon which my patent has expired, which still baffles antenna engineers to explain it. However, I have it all figured out. I built a new one of new parts for $5.00. It is the supports that are expensive.

Here is the maximum possible design (there are only three dimensions) for extremely low angle propagation (requiring fewer hops, at less loss per hop), with maximum broadbandedness (with a load almost like a dummy load), of proven merit (the Army "OE254" almost copies it, and Channel Master's "Omega" is a two element version of my three element ground plane type, and their scanner vertical antenna on many chimneys, with three legs into three finger spreads, borrows from it) patent expired, a real sleeper.  Revive it.


HOW IT LOOKS (drawings)

You all have heard "unreasonable" bragging of how good "sloper antenna" work. This system uses three slopers. You have seen how "image antennas" diagramed underground explain the cancellation of the very low angles of radiation.  Not here.

Imagine a vertical doublet. Now split the wires into three strands. Spread each strand, by exactly 90 degrees away from each other strand.  Position the strands to appear to be continuous through the feedpoint, at the center as in Fig. 1.

Look down from above it and see it as in Fig. 2 with the visible distance of the wire greatly exaggerated.  Notice that the edge lines of a cube at the corners are identical with this antenna wire elements in space, 90 degrees apart from each other.

From the ground look up, lengthwise, endwise up one element.  Past the center, the opposite is obscured endwise, also.  However, the other four elements are all seen flat broadside. They look like a perfect X, with exactly 90 degrees spread between adjacent elements as in Fig. 3.

If you make yours out of coated #18 wire and clear glass insulators, it is almost invisible to a neighbor.


HOW TO SUPPORT IT

To keep the elements properly spaced, you will need a rope or kite string or a (clear nylon) fish line triangle across the tops, and another across the bottoms. Use a line with over 50 pounds breaking strength.

This pair of spacing triangles is shown looking down onto the triangles in which the nearer upper triangle is shown bolder in Fig. 4.  Notice the three 60 degree dotted angles.  That 60 degrees is the absolute maximum width of variation of tile support lines to keep the sides of the triangle tight. Try to keep within half of that angular range. The lower three element ends may either be tight, or with a weight and an offset fishline, but also within their limits of angle.  It will still work well even if you abuse the shape temporarily.

Thus, the antenna can be very inexpensive, of ideal construction, but the supports may take amateur ingenuity.

Fig. 5 shows how to dangle twin lead from a single glass insulator in the center and to bind the lead with many turns of plastic tape, draping the lead loosely to the shack.


HOW IT WORKS

It splits your signal into three equal strength amounts (because you made all of the six elements IDENTICALLY ALIKE down to the number of turns on the soldered loops on the insulators).  These three signals are substantially equal and are 90 degrees apart. Thus, the fields from each wire are independent from the other two doublets, each 90 degrees apart from each other. (Computer programs on antennas do NOT factor this in -- sorry!)

Now, it is well established that both vertical and horizontal antennas emit fields that reflect off the ground with a 180 degree reversal.  This reversal practically neutralizes the distant signals under 5 degrees, and it still causes great loss even at 20 degrees. The result of these cancellations of the strongest and lowest lobes is a lesser strongest lobe near 25 degrees.

Apparently there is no way for the earth to effectively reflect your 3D signal in a reversed polarity to neutralize your very low angle radiation. Thus, the Bonadio Space Dimension, or 3D, Antenna cannot be improved upon as it is the limits, by evolution of three other patented antennas, to the whole extremes of 3D at 90 degrees apart from 90 degrees apart from 90 degrees.  There are no more worlds to conquer.  This does it.

In Fig. 6, you can see that a two hop reflection at -10dB per reflection can cost -30dB, but one low angle hop has less loss, say -6dB, and it dominates when half way around the world or farther.  You will hear, "You're the only American whom I can hear on the band."


ELECTRICAL CHARACTERISTICS

The Bonadio Space Dimension -- or let's call it the "Bonadio 3D", has almost no reactance to trouble us with at any frequencies higher than its first (longest wavelength) resonance. Its reactance value probably does not exceed a very low +/-10 ohms. The mismatch of the feeders will generate more reactance than the antenna itself, unlike slim wire antennas.

Do not try to feed this antenna through a balun, because neither the balun nor the antenna will hold back your harmonics. See a previous story in this series for a tuner design that will tune easily, have no power factor problem, and that filters down harmonics very well.

The load will approximate 200 ohms from its longest first resonance to all shorter wavelengths.  Use twin lead, preferably kilowatt transmitting twinlead (see Belden catalogue) because it is more permanent.  However, Radio Shack has usable outdoor twinlead in a brown color.

Notice that you can tune the antenna into your receiver and peak it before using your transmitter at "tune" so that it loads easily.  Avoid tuners with differential capacitors such as the old Matchboxes, or where your feeders tap into mid-turn of coils as in Transmatches.  They can, half of the time, show you SWR's of 1:1 and still not deliver half of your power in or out as explained in an earlier story in this AM Press/Exchange series.


WHAT TO EXPECT

Excitement!  You will immediately hear DX better than you have heard it before -- and they will be hearing you, where they never heard you before.

Expect to not get reports of fading as much as you are used to getting.

Expect to have to ASK as to how signal your signal now compares with other American signals that he has just been hearing, or really his report is meaningless.

Expect to have to explain to your neighbors that this thing is really "an electric day and night passing bird counter, just disguised as an antenna".

Expect that you will have to assign some of the rest of your family to take care of all those great QSL'S.

Expect that you will need QSL's to satisfy nearby hams who hear you, but do not hear your DX.  (Yes, you will have extended ground wave also.)



BONADIO SPACE DIMENSION ANTENNA
Optimum Dimensions
Lowest
band of
operation
Each
Arm
Triangle
Side
Vertical
Space
Support
W/8’
2 mtrs 2’ 5” 3’ 4” 2’ 9” 11’
6 mtrs 7' 2" 10' 2” 8' 2" 16'
10 mtrs 12’ 17’ 13’ 7” 22’
15 mtrs 18' 25' 5" 20' 5" 29'
20 mtrs 24’ 34’ 27’ 3” 35’
40 mtrs 48’ 68’ 55’ 63’
75 mtrs
90’ 127’ 102’ 110’
160 mtrs
192’ 272’ 218’ 226’




EXCHANGE
(Contact information removed; ads are from 1989.)

FOR SALE: Tubes new boxed 805 $20 each. 813 $20 each. 814 $10 each. Octals & locktals $2 each. Dow coax relays 115v $20 each. 1 KW 115v isolation transformer $50. Variacs 115v 15 amp powerstats $50. Plate transformers, high current filter chokes 400 ma $35 each. Components for linears inquire. Levy (the tube man).

WANTED: Manuals for the Heathkit pair. MR-1. MT-1. Will pay for shipping and copying. Marty Drift.

FOR SALE: RME DB22A preselector. 540 kc - 42 mc in 4 bands. Version with grey wrinkle case and chrome tuning knob, 2 6BA6 tuned RF stages, and built-in power supply. Good physical condition and works (recently checked out), but some scratched spots on paint. No manual. $30 plus shipping. WANTED U.T.C. LS-18, LS-49 audio transformers. Also Chicago BD-2. K4KYV.

WANTED: Good used or new type 304TL tube. Advise price and condition. Bill, KD0HG.

FOR SALE: Heathkit TX-1 Apache transmitter. Heathkit RX-1 Mohawk Receiver and SB-10 Sideband adaptor. Sell as set only. $300. Call, leave phone no. if I am not home.

WANTED: Info or schematic for Elenco "Power Gainer" audio compression amp, circa 1959. John Morehead, N9HRS.

WANTED. Patterson PR-15 receiver; clean but need not work. Any wavemeters, any age or condition. Rick Ferranti, WA6NCX

WANTED: Driver transformer single plate to pushpull grids (807's) for Viking II transmitter.  Also wanted NC-300 in excellent condition. Howie Jack, W2NRM.

WANTED: Steel relay rack meter panel 5-1/2" high for (5) 3" meters. James Schliestett, W4IMQ.

FOR SALE: Johnson Thunderbolt $450. 6N2 $75 (with VFO). Ranger II $150. WANTED: 4-1000A socket, bakelite panel meters, Johnson Valiant, 830B tubes, TV-2 tube checker. Parker, W1TG.



Doctor Marty's Heathkit Service

Looking for that old Heathkit you missed building years ago? Need a manual? Want to trade, sell, buy, parting an old rig out? Need parts? Place your needs with us and maybe we can be of help. All needs will be placed on master list. In order to get master list just send large SASE to: Marty Drift.



Keep Those Articles Coming!

If you have submitted an article in the last few months, please do not assume it was rejected for publication because it has not yet appeared. Articles are not necessarily published in the same chronological order in which we receive them. Lately, because of the urgent AM power issue, space has been limited for our normal articles, and there is presently a backlog of good articles waiting for space available. We still need a steady supply of new articles or the supply will soon become depleted.



This is the AM PRESS:

An amateur radio publication dedicated to Amplitude Modulation.

This is the AM EXCHANGE:
Offering FREE ADVERTISING to enhance the availability of AM equipment and parts.

Edited and published by Donald Chester, K4KYV

NOTICE: The purpose of this publication is the advancement of Amplitude Modulation in the Amateur Radio Service, and there is no pecuniary interest. Therefore, permission is hereby expressed for the use of material contained herein without permission of the publisher, with the exception of specifically copyrighted articles, provided that The AM Press/Exchange is properly credited.