# Vertical Aerials on MN Ships



## Worldspan (Jan 2, 2012)

Never done a cruise and not been on a cross-Channel ferry since before the tunnel opened, but I've just returned from a trip to Corsica with Corsica Ferries. 

There were various aerials on the upper deck including what must have been an MF/HF (?) vertical. Unsurprisingly there was no long wire of the type we had on Orontes in the 1950s. I know that the RN had verticals, presumably because they were less likely to suffer damage, but when did verticals come into general use on merchant ships? Were they fitted before the demise of the RO? Did some ships have both MF and HF verticals in addition to a long wire? Any comments on how they compared with each other?

W


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## BobClay (Dec 14, 2007)

One factor would be that wire aerials were cheap and easily replaced. I sailed with a few big transmitter whips, one that had to be hand cranked down for some bridges we passed under, which was quite a job.

I also have heard stories of similar whips being blown apart by lightning strikes which would be a bit of a problem compared to a bit of wire and a couple of insulators.


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## Wismajorvik (Dec 29, 2011)

Recollect some stern trawlers were fitted with 35 ft whips (Bantex/Shakespeare222 ?) which did not survive conditions in Northern fishing grounds.


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## Troppo (Feb 18, 2010)

Ships use verticals now as they are easy to replace, and the lowest tx freq they have to cover is 2 MHz, so a 10m vertical is relatively efficient.

Loaded 15m verticals with capacity top hat arms were used from the late 70s. They were very average on 500, as you would imagine. But on HF, they worked well, as they were often approaching a quarter wave.


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## Ron Stringer (Mar 15, 2005)

More comment and information here

http://www.shipsnostalgia.com/showthread.php?t=182881,

here

http://www.shipsnostalgia.com/showthread.php?t=36205

and here

http://www.shipsnostalgia.com/showthread.php?t=22764http://


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## BobClay (Dec 14, 2007)

Right Ron.

Posting links to previous posts (when we might have made after having a few) is cheating.

I propose, we shoot Ron, or if that's not acceptable, make him wear a pointy hat with a big D on it for a century ... or so.

(Jester)


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## Ron Stringer (Mar 15, 2005)

Bob,

Worldspan was looking for information about whip/mast antennas and rather than type out a load of info (similar to that others have already posted on SN) I preferred to take the lazy man's way out and just give him the links to previous postings. Remember I was a Radio Officer - never go looking for work and get ashore as soon as possible after she ties up - was the motto.

Fire away all you like Bob, you'll find I'm a hard target to hit. So far I have survived falling out of a moving car as a child, TB as a teenager, six years at sea visiting doubtful establishments, in unsalubrious places, whilst seriously under the influence of alcohol, 42 years working for Marconi, followed by bowel cancer, liver cancer, prostate cancer, skin cancer and radiation-induced colitis and proctitis. 

If you think a few bullets are going to bother me you must be living in cloud cuckoo land (or Cornwall as we call it). I'm fireproof.


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## BobClay (Dec 14, 2007)

OK, it didn't occur to me you would take it so seriously, it was meant in jest.

Consider this the end of the matter.


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## 5036 (Jan 23, 2006)

Ron Stringer said:


> Bob,
> 
> Worldspan was looking for information about whip/mast antennas and rather than type out a load of info (similar to that others have already posted on SN) I preferred to take the lazy man's way out and just give him the links to previous postings. Remember I was a Radio Officer - never go looking for work and get ashore as soon as possible after she ties up - was the motto.
> 
> ...


Tell us all what you drink Ron. I might try a few tonight.


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## J. Davies (Dec 29, 2010)

I sailed with vertical antennas on a few ships as R/O. They came to prominence in the 1980s because technology then allowed for remote-operated external tuners, or sometimes automatic remote tuners, usually mounted at or near to the base of the antenna. Prior to that the tuner was in the radio shack with open wire feeder up to wire antennas.

Verticals offer great omni-directional performance on HF because the ground plane is your steel hull connected to the perfect salt sea.

They were rather inefficient below about 2 MHz due to the short length of the vertical antenna compared with a wavelength on 500 KHz. Some ships still needed a long-ish wire strung somewhere for 500.....

Just my experiences...


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## J. Davies (Dec 29, 2010)

Just to rattle on a bit more...

Using remote tuners meant that the output from transmitter could be 50 Ohm unbalanced, so the tuner/antenna was fed with coaxial cable rather than open copper feeders. That made installation much easier : coaxial cable can be run through the ship the same as any other cable. 

The take-off angle of vertical antennas is low , which means good long-distance communications. Another advantage compared with random wire lengths which often wasted energy straight up to the clouds.

SP Radio (Sailor) and SAIT had auto-tuners mounted up on the monkey island. There must have been others.

So verticals were in use on ships built after around 1979 quite extensively, which is before the demise of the R/0.

Now in the GMDSS era all antennas are vertical, especially as there are no requirements for communications below 2 MHz.

I have definitely said my piece now....


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## MikeK (Jul 3, 2007)

We received a double lightning strike in the Indian Ocean one morning. On checking round for damage the big whip antenna was just a stump bolted to the M/Island deck, the rest was scattered round the bridge in shards ! This antenna was the highest structure on the ship and first in line to the Gods, the next was the radar scanner and the second bolt melted a little hole in that ! Needless to say just about all our communication equipment was kaput and we had one radar and VHF only for quite some time until shore help was available. As the Satnav was also a victim, out came the sextant and the chronometer !


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## King Ratt (Aug 23, 2005)

My post from Aug 2005. How about the Deichmann ((??) Klapper antenna which I observed on the British Forth in 1982?. It was a vertical loaded whip which seemed to operate on everything from 5 ton thru to 22 mhz.
RFAs used a remote base tuned whip for their Marconi Type NT204 HF transmitter aka Naval Type 640. Worldspan/Oceanspan/Reliance/Globespan all used long wires.


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## Ron Stringer (Mar 15, 2005)

BobClay said:


> OK, it didn't occur to me you would take it so seriously, it was meant in jest.
> 
> Consider this the end of the matter.


Sorry about that. I wasn't upset and took it as a joke - hence the wind-up about Cornwall. Easy to give the wrong intention when texting/messaging.


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## Naytikos (Oct 20, 2008)

Either Ron has a good memory for threads or a custom cross-reference system.

I never sailed with a transmitting vertical, but had a receiving type on the starboard Samson post on my last ship. I was impressed with it so ordered another one plus 500 feet of RG8 and mounted it on the port Samson post. Threading the co-ax back through the deck trunking and up inside the superstructure took a while but one has to pass the time somehow.

I did have the idea of ordering a ham-type three-element beam and mounting it on top of one of the twin funnels, but then realised it wouldn't survive the temperature of the exhausts.


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## Bill.B (Oct 19, 2013)

First ran into commercial vertical whips in early 80s on CP Ships Port Quebec. Worked great on HF but like Bob said was a pain to crank down. Have replaced loads, mainly Comrod AS9s due to lightning. Cable ship Global Link had two within 4 days due to strikes. Didn't seem to matter if isolated or earthed they still go hit. In low humid cloudy weather they attracted static something rotten and were a pain. Same thing in rain. Wire were much better in those conditions. The Comrods greatest weakness after a few years was the top whip joint wore out and sometimes fell off. The Europeans had the right idea and mounted them on the slant to keep it under tension. Unlike wire aerials whips were not directional.


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## Tony Selman (Mar 8, 2006)

Malcolm, I believe I answered this question previously but as you know, wine, little grey cells ..... I sailed on Maturata/GTVL for a year and also coasted her sister Maskeliya/MRSQ. The antenna (aerial) on the funnel was a transmitting whip. I have no idea whether it was one of the first but it must have been pretty early. The idea was fine in theory but transmitting aerials and funnel gases (turbine ship) are not the best of bedmates. The perennial problem of salty insulators did not help much either. They had to be cleaned quite regularly. I seem to recall that they worked best on 12MHz. Unusually for a Brocklebank ship I only sailed on her on the North Atlantic as she was on charter to Anchor Line, mainly carrying whisky from Glasgow the NE USA ports. There was not much need to go on frequencies higher than 12MHz so cannot recall performance higher than that. Brock's had a long track record of whip antennas on funnels and there is a story, true as far as I know, of one snapping off mid voyage and nearly impaling someone bronzieing on the monkey island.


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## Tony Selman (Mar 8, 2006)

I joined Maturata for the above voyage in Manchester, obviously with no funnel. I did not really think too much about this until nearing the Eastham funnel park in the dark and the thought occurred to me how the hell do I get everything reconnected. Luckily a previous R/O had spelt it out chapter and verse in the handover book and what could have been a disaster was easy.


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## trotterdotpom (Apr 29, 2005)

Not sure when it started but in the '70s, lots (most?) of German ships had a vertical aerial with a cartwheel on top of it. Presume it was a DEBEG idea - whatever, it seemed to work on all frequencies.


Those AS9 aerials, previously mentioned, were always packing in. They were a pain in the arze to wind down too., On one ship I thought I was going to have to do it with a big spanner until the proper gadget turned up down the engine room somewhere - they didn't know what it was so they put it in a locker. At least with the proper too, the lowering only took a day!

John T


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## Ron Stringer (Mar 15, 2005)

[quote=trotterdotpom;2630537]Not sure when it started but in the '70s, lots (most?) of German ships had a vertical aerial with a cartwheel on top of it. Presume it was a DEBEG idea - whatever, it seemed to work on all frequencies.[/quote]

John that would have been the _Dieckmann & Klapper MAS140_ Antenna. You can see a photo of a ship fitted with one in one of the links in my post#14, this thread. 

Took some getting used to when setting up a _Crusader _or other transmitter on it for the first time on a newbuilding - the taps/settings were quite different to what we were used to on the usual open wire antennas .


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## trotterdotpom (Apr 29, 2005)

#23 . Thanks Ron. Only used them with DEBEG gear - forget now but they may have been ITT knockoffs. Always worked fine. Mind you, I just copped whatever I sailed with. I thought you weren't supposed to alter the installation!

John T


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## Ron Stringer (Mar 15, 2005)

trotterdotpom said:


> #23 . I thought you weren't supposed to alter the installation! John T


It was during the installation that the setting-up was done, John. 

Debeg bought a lot of _Crusader/Apollo_ stations from MIMCo (they and Radio Holland were by far the biggest customers for them) and if there were problems, Muggins (or one of my team) was sent to sort them out. Most awkward were the fittings with a MAS140 mast antenna as main, with a short wire as the reserve. Getting proper tuning and matching on MF with the _Crusader_ could be a bit of a b*gger; it could be difficult to achieve the required metre-amps on the reserve while preserving the normal performance on the main antenna. It had to be a compromise. There was a lot of power in those beasties and care had to be taken if you were to avoid lots of pyrotechnics.

I remember similar problems, but not so extreme, with the _Conqueror_ range of transmitters which had even more power but had the advantage of better antenna matching arrangements. By that time the _Comrod AS9_ antenna had replaced the MAS140. I had several such visits to overseas shipyards, mainly in Europe, dealing with such affairs, including a memorable trip on builder's sea trials out of Bremen aboard the _Zim Montreal_.


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## trotterdotpom (Apr 29, 2005)

#25 . "It was during the installation that the setting-up was done, John. "

I realise that, Ron, I was referring to other R.O. comments on this and other threads. 

John T


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## Worldspan (Jan 2, 2012)

Well, I never expected such a detailed and thorough response to my query about vertical aerials! Very many thanks for all the replies.
W


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## ernhelenbarrett (Sep 7, 2006)

Had a Vertical main Tx Antenna on the Cycle/VKAC ex Norwegian "Hansa" but it
didn't last too long as the lot went overboard during excessive rolling in the Aussie Bight between Fremantle and Adelaide. Managed to make up a wire Main
Aerial using every bit of wire I could find until re-rigged with Wire Aerial in Adelaide, that ship sure could roll on a blade of wet grass.
Ern Barrett


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## richardwakeley (Jan 4, 2010)

Blue Funnel's 'Super P' class of the late 60s had vertical whip antennae, both sides of the funnel. So, as in all the comments above, HF communications were great but MF very limited range compared to the older ships with triatic stay aerials, despite having Globespan instead of Oceanspan.


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## P.Arnold (Apr 11, 2013)

Ron Stringer
Took some getting used to when setting up a [I said:


> Crusader [/I]or other transmitter on it for the first time on a newbuilding - the taps/settings were quite different to what we were used to on the usual open wire antennas .


Had same problem with the Marconi ‘Challenger’ installations with AS9 and ‘short’ wire aerials on MF. With manufacturers taps, could get 410 to 500 or 454 to 512 but not the whole 410 to 512. A little jiggery pokey with the internal positioning of taps was called for.

Can’t recall what the metre/amps regs were, but surveyors were not impressed unless you got a good indication on all MF freqs on both aerials.

Ron, sure I did mention it in an M401.! 

Was getting wiser, but clearly not.


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## trotterdotpom (Apr 29, 2005)

ernhelenbarrett said:


> Had a Vertical main Tx Antenna on the Cycle/VKAC ex Norwegian "Hansa" but it
> didn't last too long as the lot went overboard during excessive rolling in the Aussie Bight between Fremantle and Adelaide. Managed to make up a wire Main
> Aerial using every bit of wire I could find until re-rigged with Wire Aerial in Adelaide, that ship sure could roll on a blade of wet grass.
> Ern Barrett


Well, that solved the vertical aerial problem, Ern! Don't remember the ship "Cycle" - any details?

John T


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## Ron Stringer (Mar 15, 2005)

P.Arnold said:


> Ron, sure I did mention it in an M401.!


Well Pete, the Service or Installations dept person that received it never passed it on to us - but we wouldn't have been surprised if they had. All the MF transmitters that I sailed with were similarly limited - going back as far as the _Oceanspan _and _Reliance_. The _Salvor _series of transmitters had a better matching/tuning range than the others but even they had problems over the whole MF frequency band when the main/reserve antenna characteristics were widely different.

Of course when such transmitters were in production, most ships had tall masts and above-deck arrangements that made it relatively simple to rig two transmitting antennas with similar enough electrical characteristics to encompass them easily within the tuning capabilities of the transmitters. Even if this was not perfect and significant mismatch was present, reducing antenna current, the antennas were rigged high enough to achieve the required metre-amp figures). 

It was later that problems arose with meeting metre-amps requirements, and with tuning to dissimilar antennas, because antennas were no longer permitted over working decks and had to be rigged within the area of the accommodation and because only a signal mast or the funnel (both relatively low structures) were available as suspension points.

I was told that the _Oceanlink EMX_ and the (virtually identical) MF section of the _Oceanlink 400_ and _Oceanlink 800_ main transmitters) were able to accommodate such differences but I never sailed with them and no longer went out to ships when they came into service. They were self-tuning which helped. 

Nothing to do with tuning but those transmitters also used very advanced (for the time) digital techniques for shaping and controlling the modulation and keyed waveform. Meeting the 'envelope' for spurious emissions was a doddle for them - something of a struggle for all the earlier designs that required the most experienced of designers to meet the specifications in a stable and consistent manner. Once things went digital a newly-qualified design engineer could do it with his eyes shut. Pity that the age of marine MF and HF communications using Morse was coming to a close by that time!


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## Naytikos (Oct 20, 2008)

One of the interesting things about the thermo-couple meters used to measure aerial current in most MF transmitters was that they are/were easily 'recalibrated' and could be made to show whatever current was required to achieve the regulation metre-amps.


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