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Rhombic antenna "gain"

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Ken G Kopp

Rhombic antenna "gain"

Rhombic antennas derive their well-known gain by "throwing away" some of
the design's gain. Ditto for the infamous "inverted vee". Use is made of
the lobes from the four wires while disregarding others.

73 !

Ken Kopp - K0PP
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Mike Markowski-2

Re: Rhombic antenna "gain"

Can you expand on this, Ken, or if easier, a reference? I'm curious
what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before
the Army base was closed in 2011, and used to boom into Europe and
Russia. It was amazing. I also got copies of WWII manuals on rhombic
construction while there. You know, just in case I became wealthy with
tens of acres of land. :-)

73,
Mike ab3ap

On 9/13/19 5:57 PM, Ken G Kopp wrote:
> Rhombic antennas derive their well-known gain by "throwing away" some of
> the design's gain. Ditto for the infamous "inverted vee". Use is made of
> the lobes from the four wires while disregarding others.
>
> 73 !
>
> Ken Kopp - K0PP
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EricJ

Re: Rhombic antenna "gain"

Maybe the termination was changed in later years. I was permanently
assigned to K2USA from '63-'65 (not bad duty for a ham). We ran
thousands of phone patches to/from SE Asia on that rhombic and the 20m
monobander @ 90 feet. I used to break into QSOs between two local VKs
chatting via ground wave with that antenna. I was the only signal they
could hear.

You probably knew Mike Reason. When I was there, he was a local kid who
used to hang out at the MARS station. Great guy, now SK.

Eric KE6US

ex-K1DCK, WA6YCF, WB2PVW

On 9/13/2019 3:24 PM, Mike Markowski wrote:

> Can you expand on this, Ken, or if easier, a reference? I'm curious
> what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before
> the Army base was closed in 2011, and used to boom into Europe and
> Russia. It was amazing. I also got copies of WWII manuals on rhombic
> construction while there. You know, just in case I became wealthy
> with tens of acres of land. :-)
>
> 73,
> Mike ab3ap
>
> On 9/13/19 5:57 PM, Ken G Kopp wrote:
>> Rhombic antennas derive their well-known gain by "throwing away" some of
>> the design's gain. Ditto for the infamous "inverted vee". Use is
>> made of
>> the lobes from the four wires while disregarding others.
>>
>> 73 !
>>
>> Ken Kopp - K0PP
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> Elecraft mailing list
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donovanf

Re: Rhombic antenna "gain"

In reply to this post by Mike Markowski-2

Hi Mike,

Rhombic antennas -- with few exceptions -- were not usually designed
for high gain. They were usually designed as a compromise between
gain and typically one octave of bandwidth (e.g. 14-28 MHz).

To compound the design compromises, the r hombic termination
resistor throws away nearly 3 dB of whatever gain it might achieve.
Because of this, high gain transmitting rhombics have very narrow
beamwidth, typically 20-30 degrees.

A high gain rhombic designed for 14-28 MHz -- competitive with a pair
of stacked large triband Yagis -- might be 300 feet wide, 700 feet long
and supported by four 100 foot towers. In order to achieve this gain,
the rhombic beamwidth would be only about 25 degrees, requiring at
least a dozen huge reversable rhombics to cover most of the compass.

I visited many rhombic antenna farms many years ago (as far as I know
they've now all been dismantled). They were typically at least one square
mile sites with fifty to a hundred towers with heights of 50 to more than
200 feet. Dismantled VOA Site C in Greenville, NC is a good example,
a 1.5 square mile site with pairs of massive rhombics -- the biggest I've
ever seen -- for diversity reception.

To the extent these facilities are still operating (the vast majority are not),
the rhombics were replaced by rotatable log periodic antennas, perhaps
with higher power transmitters to make up for the slightly reduced gain.
That approach replaces a one square miles ( in some cases much larger)
with a few acres or perhaps 100 acres for very large site.

This is a good reference:

www.w8ji.com/rhombic_antennas.htm

73
Frank
W3LPL

----- Original Message -----

From: "Mike Markowski" <[hidden email]>
To: [hidden email]
Sent: Friday, September 13, 2019 10:24:32 PM
Subject: Re: [Elecraft] Rhombic antenna "gain"

Can you expand on this, Ken, or if easier, a reference? I'm curious
what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before
the Army base was closed in 2011, and used to boom into Europe and
Russia. It was amazing. I also got copies of WWII manuals on rhombic
construction while there. You know, just in case I became wealthy with
tens of acres of land. :-)

73,
Mike ab3ap

On 9/13/19 5:57 PM, Ken G Kopp wrote:
> Rhombic antennas derive their well-known gain by "throwing away" some of
> the design's gain. Ditto for the infamous "inverted vee". Use is made of
> the lobes from the four wires while disregarding others.
>
> 73 !
>
> Ken Kopp - K0PP
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k6dgw

Re: Rhombic antenna "gain"

In reply to this post by Mike Markowski-2

Mike: Rhombics can be operated either terminated or unterminated. If
unterminated, they are bi-directional with half the power in each lobe.
If terminated, the resistor absorbs half the power in the reverse lobe.
Either way, half your power goes the "wrong" way, either behind your
desired direction or heats a big resistor. They have a very low
radiation angle and a fairly narrow beamwidth which is why they're flame
throwers and very common in military and commercial stations,
particularly in the days of point-to-point radio circuits. V-beams,
sometimes called Half-Rhombics are sort of likewise only broader azimuth
patterns more suitable for maritime ship-shore telegraphy circuits. For
ham applications, Google W6AM

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 9/13/2019 3:24 PM, Mike Markowski wrote:
> Can you expand on this, Ken, or if easier, a reference? I'm curious
> what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before
> the Army base was closed in 2011, and used to boom into Europe and
> Russia. It was amazing. I also got copies of WWII manuals on rhombic
> construction while there. You know, just in case I became wealthy
> with tens of acres of land. :-)
>
> 73,
> Mike ab3ap

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David Haines

Re: Rhombic antenna "gain"

In reply to this post by Mike Markowski-2

Well, I'm not wealthy. But we do have 270 acres of forest-land covered
with nothing but trees. So a rhombic or two sounds really good, which
never occurred to me before. Thanks, Don!

Across the field from my shack, maybe 600', is a row of 90' pine
trees. More trees on either edge of the field for the vertices. And the
feed could be right at the shack. How important is symmetry?

I've been deciding how much Wireman #534 to buy, so it sounds like I
should go for at least 1000'! Still will need a lot of support line,
though.

david, in the forests of Maine

KC1DNY

On 9/13/2019 6:24 PM, Mike Markowski wrote:

k6dgw

Re: Rhombic antenna "gain"

In reply to this post by Mike Markowski-2

Mike: You will need more than "a few tens of acres" for rhombics, their
beamwidth is so narrow that you will need an array of them. The
transmit site for KOK ["Los Angeles Radio" now SK and demolished] was
probably at least a square mile, likely more. Rhombics for the
point-2-point services, horizontal V-beams for the maritime service.

VOA was partial to Sterba and other "curtain" designs. Similar to
rhombics in the gain and main lobe elevation departments, they exhibit
wider beam widths which was good for broadcast to specific areas instead
of specific cities. VOA had a large station in Dixon CA with multiple
curtains which is gone now. The one in Delano CA was still there
[inactive] last time we drove down CA99 to Bakersfield 5 or so years
ago. They do require two or more very tall towers however.

There's a trade-off equation. Rhombics are quite simple and do not
require massive towers. They DO require a lot of land which must be
factored into the total antenna cost. That land has to be kept clear of
major vegetation too. Curtains take less land but are substantially
more complex and more difficult to erect, inspect, and maintain. It
always comes down to money. [:-))

Don Wallace, W6AM, was a legend on the west coast in the 40's/50's. His
QTH was in the Palos Verde Hills [west of downtown Los Angeles]
overlooking the Pacific with multiple rhombics. At that time, transmit
power was measured by plate input power and our limit was 1 KW. W6AM
had separate Collins KW-1 transmitters permanently tuned for each band,
all the feedlines were open wire, and he basically talked to anyone he
wanted to. I got a chance to visit the station as a teenager with a
group ... had to ask my Elmer about the looong wires about 8 ft off the
ground ... beverage RX antennas under and around all the rhombics.

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 9/13/2019 3:24 PM, Mike Markowski wrote:

Jim Campbell

Re: Rhombic antenna "gain"

In reply to this post by Mike Markowski-2

In the late '50s I was stationed at a field station in Northern Germany
that was monitoring transmissions from the 'other side'. We were at a
former WWII German airfield and had an antenna farm comprised of
rhombics. I never bothered to count how many there were but I estimate
that there were more than a dozen and they were in the order of 90'
above ground. I was a ham at the time (DL4AQ) but not active.

I believe that my K2 and a low 88' doublet hears better than would a
rhombic and a SP-600 from those days. I almost can't believe the signals
I'm hearing at the bottom of the sunspot cycle with said K2 and low 88'
doublet. The old days weren't the good old days.

73,

Jim - W4BQP

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Alan Bloom

Re: Rhombic antenna "gain"

In reply to this post by k6dgw

Many years ago W1AW used to have a big (6 wavelengths per leg as I
recall) rhombic for 20 meters pointed west. It was mainly used for the
code practice and bulletin transmissions. When the new 90-foot tower
with stacked monoband Yagis was installed we ran some A/B antenna tests
on the air and asked people to send in signal reports.

We found that the rhombic was equal or better than the stacked
monobanders right on the boresight of the antenna but it had a narrower
radiation pattern. The Yagis covered the west coast better overall.

On the other hand, the rhombic was not as high (mounted on telephone
poles) and it could be used on other bands, although with lower gain.

By the way, the W1AW rhombic was unterminated as I recall. There really
is no need to terminate a rhombic unless you are concerned about
interference (on receive or transmit) in the rear direction.

Alan N1AL

On 9/13/19 4:21 PM, Fred Jensen wrote:

> Mike: Rhombics can be operated either terminated or unterminated. If
> unterminated, they are bi-directional with half the power in each
> lobe. If terminated, the resistor absorbs half the power in the
> reverse lobe. Either way, half your power goes the "wrong" way,
> either behind your desired direction or heats a big resistor. They
> have a very low radiation angle and a fairly narrow beamwidth which is
> why they're flame throwers and very common in military and commercial
> stations, particularly in the days of point-to-point radio circuits.
> V-beams, sometimes called Half-Rhombics are sort of likewise only
> broader azimuth patterns more suitable for maritime ship-shore
> telegraphy circuits. For ham applications, Google W6AM
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County

Jim Campbell

Re: Rhombic antenna "gain"

In reply to this post by Jim Campbell

We also had Elephant Cages later on. Funny no one has mentioned them. If
you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9
Also known as a "Wullenweber" or AN/FLR-9.

Jim - W4BQP
On 9/13/2019 8:28 PM, Dick Dievendorff wrote:

> Small world. I was in a similar line of work, for the Navy, using an R-390,
> but I don't think we had Rhombics. This was in the mid-60's
>
> Lots of us in ham radio.
>
> 73 de Dick, K6KR
>
> -----Original Message-----
> From: [hidden email] <[hidden email]> On
> Behalf Of Jim Campbell
> Sent: Friday, September 13, 2019 17:21
> To: [hidden email]
> Subject: Re: [Elecraft] Rhombic antenna "gain"
>
> In the late '50s I was stationed at a field station in Northern Germany that
> was monitoring transmissions from the 'other side'. We were at a former WWII
> German airfield and had an antenna farm comprised of rhombics. I never
> bothered to count how many there were but I estimate that there were more
> than a dozen and they were in the order of 90'
> above ground. I was a ham at the time (DL4AQ) but not active.
>
> I believe that my K2 and a low 88' doublet hears better than would a rhombic
> and a SP-600 from those days. I almost can't believe the signals I'm hearing
> at the bottom of the sunspot cycle with said K2 and low 88'
> doublet. The old days weren't the good old days.
>
> 73,
>
> Jim - W4BQP
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html Message
> delivered to [hidden email]
>
>

Jim Brown-10

Re: Rhombic antenna "gain"

In reply to this post by donovanf

On 9/13/2019 4:18 PM, [hidden email] wrote:
> To compound the design compromises, the r hombic termination
> resistor throws away nearly 3 dB of whatever gain it might achieve.

When our senior EE class toured Crosley's Mason, OH VOA site in 1964,
the engineers were quite proud of their modification to the design that
fed the termination power back into the feedpoint. All that remains of
that spectacular station is the transmitter building. When we toured it,
there were >25 rhombics and two Sterba Curtains. 10-15 years ago, my son
worked as the manager for a restaurant/bar on the land where the antenna
farm used to be. Several years ago, I drove by the VOA station at
Delano, CA, about 45 miles S of Visalia. At least some of the antenna
farm was still there, but inquiry told me that the transmitters were
"somewhere in South America." At the time, I had hopes of arranging a
tour for Visalia DX Convention attendees.

There are still some shore stations along the Pacific coast with
rhombics. The KPH TX and RX stations are 30-40 miles apart. There's
another RX station along Rte 1 S of Half Moon Bay, with an associated TX
station around Palo Alto.

73, Jim K9YC
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Richard S. Leary

Re: Rhombic antenna "gain"

In reply to this post by Jim Campbell

Also had an array of rhombics at Bingen, plenty of SP-600's. Used primarily for reception. Our GRC-26 used a dipole for xmt/rcv DF work. That was 55 to 58. I'd have loved to have my K3 and 3 el steppIR back then. They didn't get the FLR-9 at Chicksands until after I left in Jun 62. Got my ham license in Nov 61 while in G land but didn't operate until I got back stateside. Yeah, good ole days.

73,
Rick W7LKG (ex 293x1)

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Jim Campbell
Sent: Friday, September 13, 2019 17:46
To: [hidden email]
Subject: Re: [Elecraft] Rhombic antenna "gain"

We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9
Also known as a "Wullenweber" or AN/FLR-9.

Jim - W4BQP
On 9/13/2019 8:28 PM, Dick Dievendorff wrote:

> Small world. I was in a similar line of work, for the Navy, using an
> R-390, but I don't think we had Rhombics. This was in the mid-60's
>
> Lots of us in ham radio.
>
> 73 de Dick, K6KR
>
> -----Original Message-----
> From: [hidden email]
> <[hidden email]> On Behalf Of Jim Campbell
> Sent: Friday, September 13, 2019 17:21
> To: [hidden email]
> Subject: Re: [Elecraft] Rhombic antenna "gain"
>
> In the late '50s I was stationed at a field station in Northern
> Germany that was monitoring transmissions from the 'other side'. We
> were at a former WWII German airfield and had an antenna farm
> comprised of rhombics. I never bothered to count how many there were
> but I estimate that there were more than a dozen and they were in the order of 90'
> above ground. I was a ham at the time (DL4AQ) but not active.
>
> I believe that my K2 and a low 88' doublet hears better than would a
> rhombic and a SP-600 from those days. I almost can't believe the
> signals I'm hearing at the bottom of the sunspot cycle with said K2 and low 88'
> doublet. The old days weren't the good old days.
>
> 73,
>
> Jim - W4BQP
>
>
>
> ______________________________________________________________
>

Michael P. Rioux

Re: Rhombic antenna "gain"

In reply to this post by Jim Campbell

I still get a kick out of thinking that I worked INSIDE of the antenna! (Rota’s FLR-9)

Si vis pacem, para bellum

Mike, W1USN

> On Sep 13, 2019, at 8:45 PM, Jim Campbell <[hidden email]> wrote:
>
> We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 <https://en.wikipedia.org/wiki/AN/FLR-9> Also known as a "Wullenweber" or AN/FLR-9.
>
> Jim - W4BQP
> On 9/13/2019 8:28 PM, Dick Dievendorff wrote:
>> Small world. I was in a similar line of work, for the Navy, using an R-390,
>> but I don't think we had Rhombics. This was in the mid-60's
>>
>> Lots of us in ham radio.
>>
>> 73 de Dick, K6KR
>>
>> -----Original Message-----
>> From: [hidden email] <mailto:[hidden email]> <[hidden email] <mailto:[hidden email]>> On
>> Behalf Of Jim Campbell
>> Sent: Friday, September 13, 2019 17:21
>> To: [hidden email] <mailto:[hidden email]>
>> Subject: Re: [Elecraft] Rhombic antenna "gain"
>>
>> In the late '50s I was stationed at a field station in Northern Germany that
>> was monitoring transmissions from the 'other side'. We were at a former WWII
>> German airfield and had an antenna farm comprised of rhombics. I never
>> bothered to count how many there were but I estimate that there were more
>> than a dozen and they were in the order of 90'
>> above ground. I was a ham at the time (DL4AQ) but not active.
>>
>> I believe that my K2 and a low 88' doublet hears better than would a rhombic
>> and a SP-600 from those days. I almost can't believe the signals I'm hearing
>> at the bottom of the sunspot cycle with said K2 and low 88'
>> doublet. The old days weren't the good old days.
>>
>> 73,
>>
>> Jim - W4BQP
>>
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html Message
>> delivered to [hidden email] <mailto:[hidden email]>
>>
>>
>
> ______________________________________________________________
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ke9uw

Re: Rhombic antenna "gain"

In reply to this post by Jim Campbell

I was in the radio direction finding group at the U of IL in the early 60's which had a Wullenweber site just west of Champaign-Urbana IL 120 antennas in a circle outside a screen supported by telephone poles. The locals had colorful ideas of what it was all about. You could listen to WWVH, Hawaii and WWV in MD separately on the same frequency by rotating receive about 180 degrees. Very impressive.

Jack BMW Motorcycles
Chuck KE9UW
[hidden email]

Sent from my iPad

> On Sep 13, 2019, at 7:46 PM, Jim Campbell <[hidden email]> wrote:
>
> We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 Also known as a "Wullenweber" or AN/FLR-9.
>
> Jim - W4BQP
>> On 9/13/2019 8:28 PM, Dick Dievendorff wrote:
>> Small world. I was in a similar line of work, for the Navy, using an R-390,
>> but I don't think we had Rhombics. This was in the mid-60's
>>
>> Lots of us in ham radio.
>>
>> 73 de Dick, K6KR
>>
>> -----Original Message-----
>> From: [hidden email] <[hidden email]> On
>> Behalf Of Jim Campbell
>> Sent: Friday, September 13, 2019 17:21
>> To: [hidden email]
>> Subject: Re: [Elecraft] Rhombic antenna "gain"
>>
>> In the late '50s I was stationed at a field station in Northern Germany that
>> was monitoring transmissions from the 'other side'. We were at a former WWII
>> German airfield and had an antenna farm comprised of rhombics. I never
>> bothered to count how many there were but I estimate that there were more
>> than a dozen and they were in the order of 90'
>> above ground. I was a ham at the time (DL4AQ) but not active.
>>
>> I believe that my K2 and a low 88' doublet hears better than would a rhombic
>> and a SP-600 from those days. I almost can't believe the signals I'm hearing
>> at the bottom of the sunspot cycle with said K2 and low 88'
>> doublet. The old days weren't the good old days.
>>
>> 73,
>>
>> Jim - W4BQP
>>
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html Message
>> delivered to [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
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Chuck, KE9UW

k6dgw

Re: Rhombic antenna "gain"

In reply to this post by Jim Brown-10

Many of the VOA transmitters were 250 KW and ended up in religious SW
broadcast stations.

There was a small group of hams who either tried, or succeeded, in
getting permission to put one of the remaining Delano Sterba's on 160
[and maybe 80]. I'm not sure if they were successful, I do know that
the antenna farm you can see from the highway is significantly smaller
than I remember from the late 50's.

I think the Half Moon Bay stn was KFS. It's brother site was in the mud
flats off of the Palo Alto shoreline in the Bay, all gone now. At least
one of the KFS transmitters is now operating at KPH.

Feed the termination power back into the antenna? Conservation of
energy? [:-)

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 9/13/2019 5:47 PM, Jim Brown wrote:

> On 9/13/2019 4:18 PM, [hidden email] wrote:
>> To compound the design compromises, the r hombic termination
>> resistor throws away nearly 3 dB of whatever gain it might achieve.
>
> When our senior EE class toured Crosley's Mason, OH VOA site in 1964,
> the engineers were quite proud of their modification to the design
> that fed the termination power back into the feedpoint. All that
> remains of that spectacular station is the transmitter building. When
> we toured it, there were >25 rhombics and two Sterba Curtains. 10-15
> years ago, my son worked as the manager for a restaurant/bar on the
> land where the antenna farm used to be. Several years ago, I drove by
> the VOA station at Delano, CA, about 45 miles S of Visalia. At least
> some of the antenna farm was still there, but inquiry told me that the
> transmitters were "somewhere in South America." At the time, I had
> hopes of arranging a tour for Visalia DX Convention attendees.
>
> There are still some shore stations along the Pacific coast with
> rhombics. The KPH TX and RX stations are 30-40 miles apart. There's
> another RX station along Rte 1 S of Half Moon Bay, with an associated
> TX station around Palo Alto.
>
> 73, Jim K9YC
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k6dgw

Re: Rhombic antenna "gain"

In reply to this post by David Haines

Symmetry? The whole show with rhombics is beamwidth and elevation
angle, not really gain, which has been pointed out in much of the
literature. A "perfect" rhombic will have an extremely narrow beamwidth
in the 10 to 15 deg range at HF [and if large enough, at MF as well].
Asymmetry will distort that characteristic, and raise the amplitude of
side lobes. Effective rhombics for ham usage will require an "array' of
them with different headings. Lots of land, lots of property taxes.
Stacked, rotatable yagi's might be a better choice if your bank account
is sufficient. Trees growing inside a rhombic will slowly degrade its
performance, yet another cost. Of course, you might be able to sell the
lumber. [:-)

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 9/13/2019 5:01 PM, David Haines wrote:

> Well, I'm not wealthy. But we do have 270 acres of forest-land
> covered with nothing but trees. So a rhombic or two sounds really
> good, which never occurred to me before. Thanks, Don!
>
> Across the field from my shack, maybe 600', is a row of 90' pine
> trees. More trees on either edge of the field for the vertices. And
> the feed could be right at the shack. How important is symmetry?
>
> I've been deciding how much Wireman #534 to buy, so it sounds like I
> should go for at least 1000'! Still will need a lot of support line,
> though.
>
> david, in the forests of Maine
>
> KC1DNY
>

W2xj

Re: Rhombic antenna "gain"

In reply to this post by Jim Brown-10

A small correction. Delano, Dixon and further east Bethany were not VOA sites. They were originally private broadcaster’s sites. I can’t remember which was what but Bethany and Delano were CBS and NBC. Bethany was Crosley. Eventually VOA took these sites over as commercial broadcasters found little value in shortwave. Greenville was the only true VOA site on US soil.

The engineers who kept these sites going were heros as many of those transmitters became antiques and in some cases had to fabricate parts. That is the unfortunate legacy of US shortwave broadcast.

b

Sent from my iPad

>> On Sep 13, 2019, at 8:48 PM, Jim Brown <[hidden email]> wrote:
>>
>> On 9/13/2019 4:18 PM, [hidden email] wrote:
>> To compound the design compromises, the r hombic termination
>> resistor throws away nearly 3 dB of whatever gain it might achieve.
>
> When our senior EE class toured Crosley's Mason, OH VOA site in 1964, the engineers were quite proud of their modification to the design that fed the termination power back into the feedpoint. All that remains of that spectacular station is the transmitter building. When we toured it, there were >25 rhombics and two Sterba Curtains. 10-15 years ago, my son worked as the manager for a restaurant/bar on the land where the antenna farm used to be. Several years ago, I drove by the VOA station at Delano, CA, about 45 miles S of Visalia. At least some of the antenna farm was still there, but inquiry told me that the transmitters were "somewhere in South America." At the time, I had hopes of arranging a tour for Visalia DX Convention attendees.
>
> There are still some shore stations along the Pacific coast with rhombics. The KPH TX and RX stations are 30-40 miles apart. There's another RX station along Rte 1 S of Half Moon Bay, with an associated TX station around Palo Alto.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

donovanf

Re: Rhombic antenna "gain"

In reply to this post by ke9uw

Hi Chuck,

Its nearly impossible to hide those old Wullenweber arrays, even if they've
been dismantled for nearly fifty years

www.google.com/maps/search/bondville+rd,+scott,+il/@40.0492598,-88.3816964,440m/data=!3m1!1e3

73
Frank
W3LPL

----- Original Message -----

From: "charles j jr hawley" <[hidden email]>
To: "Jim Campbell" <[hidden email]>
Cc: [hidden email]
Sent: Saturday, September 14, 2019 1:42:53 AM
Subject: Re: [Elecraft] Rhombic antenna "gain"

I was in the radio direction finding group at the U of IL in the early 60's which had a Wullenweber site just west of Champaign-Urbana IL 120 antennas in a circle outside a screen supported by telephone poles. The locals had colorful ideas of what it was all about. You could listen to WWVH, Hawaii and WWV in MD separately on the same frequency by rotating receive about 180 degrees. Very impressive.

Jack BMW Motorcycles
Chuck KE9UW
[hidden email]

Sent from my iPad

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donovanf

Re: Rhombic antenna "gain"

In reply to this post by Michael P. Rioux

Hi mike,

Wasn't Rota an FRD-10, not an FLR-9?

www.google.com/maps/place/36%C2%B039'24.0%22N+6%C2%B021'54.0%22W/@36.6567863,-6.3663994,682m/data=!3m1!1e3!4m2!3m1!1s0x0:0x0

73
Frank
W3LPL

----- Original Message -----

From: "Michael P. Rioux" <[hidden email]>
To: "Jim Campbell" <[hidden email]>
Cc: [hidden email]
Sent: Saturday, September 14, 2019 1:26:20 AM
Subject: Re: [Elecraft] Rhombic antenna "gain"

I still get a kick out of thinking that I worked INSIDE of the antenna! (Rota’s FLR-9)

Si vis pacem, para bellum

Mike, W1USN

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Arliss

Re: Rhombic antenna "gain"

In reply to this post by donovanf

Or even longer:

https://4.bp.blogspot.com/-UkbdbLQ-ofI/V4CWpqwJ9SI/AAAAAAAAE-Q/YtV82_PGUqg3j77n0OyOxp0A1LaL1-LowCLcB/s1600/crop-stonehenge-stones-set3.jpg

73, Arliss W7XU

On 9/13/2019 10:15 PM, [hidden email] wrote:

> Hi Chuck,
>
>
> Its nearly impossible to hide those old Wullenweber arrays, even if they've
> been dismantled for nearly fifty years
>
>
> www.google.com/maps/search/bondville+rd,+scott,+il/@40.0492598,-88.3816964,440m/data=!3m1!1e3
>
>
> 73
> Frank
> W3LPL
>

123