# Dieckmann & Klapper MAS 140 Aerial



## Ancient-Mariner (Mar 30, 2009)

Can anyone point me to a ship photo showing a good image of a Dieckmann & Klapper MAS 140 Aerial. Google is not being my friend on this one!

Thanks

Clive


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## hawkey01 (Mar 15, 2006)

Clive,

Having not sailed with something so exotic I am not sure if they are what you are looking for. Upturned umbrella, I think is a DK aerial. I have a lot of German ships in my Gallery - the Cap boats have this as do several others. Have a look through and you may well find what you want.

Hawkey01


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## Ancient-Mariner (Mar 30, 2009)

I sailed with one on GXIC (City of Durban, ACT8, Pegasus Bay, Portland Bay) and also on Alaunia/GSEN and Alsatia/GPUG - all three Marconi fitted ships, but I don't think I have a photo of my own. A photo of GXIC on the web, although showing the starboard side, the MAS 140 is either hinged down or lost in digital compression of the photo.

The description is a vertical tapering fibreglass mast, about 400mm in diameter at the base tapering to the top. At the top of this mast, besides a fibreglass whip aerial was a tubular structure with hexagonal form. From this structure were six aerial wires connected to a ring which was about a metre in diameter. This ring then being tensioned with plastic insulators and bottle-screws to ring-bolts into the base of the fibreglass mast. The overall height being 14 metres.

From a website which has no photos, the rated frequency range was 0.2 - 25 MHz. I was at first sceptical of how it would perform, having been used to conventional wire aerials, but always had good results from MF where aerial current was always >12 amp and on hf. I certainly used 25MHz when it was used by Portishead during 1980's (or was it early 1990's?).

Reason I'm interested now is that it's MF performance and strange shape, especially the top whip, would be of interest to those radio amateurs who are using the LF band on 137 kHz. Generally for LF a vertical aerial with a capacitive hat, or umbrellor is suggested; not a highly capacitive bottom half with a single whip on top! 

73's

Clive


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## Bill Greig (Jul 4, 2006)

From the description it sounds like the antenna I had on the Makaria/GPOV. Generally it was good except in damp weather as the lower insulators were smooth and not "ribbed" as normal and so they leaked the power away badly when wet or damp.
Regards
Bill


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## david.hopcroft (Jun 29, 2005)

Clive

I don't know if this is the same version you are looking for, but it is a D & K as fitted in 1963. I was RO on the Safmarine fruit reefer 'LANGKLOOF' , for two years 1965-66. This view shows it in later life laid up as the AEGEAN PRIDE, but is the best view I can find. 

It performed well with the AEI T80 Main Tx as far as I remember except that performance on 500 was not good in the wet during a gale when the top whip bent over. Not the best of times to have that happen !!

David
+


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## Pat bourke (Jun 30, 2007)

Greetings Clive,
I sailed on MV Capulet a bulk carrier belonging to Bowring Steamship, GPAW, 1978. It had a DK antenna with Crusader as main TX. Did a lot of HF work while on there. Had a lot of problems with sun spots and also interferred with radar at times. I do not have a photo of the ship unfortunately, but there is photo of a model of the ship by *"scheepswerf260*" on this site. It gives a good view of antenna. Hope this might help you.
73s

Pat.


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## Treborvfr (Feb 22, 2010)

I'm fairly sure these aerials were fitted to the BP River class ships so a trawl through a picture library may reveal what you want. If I get chance when I return home in a couple of weeks I'll see if I have any pictures of one (if I can find them).

Bob


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## Radiomariner (Nov 7, 2008)

I sailed with DK antennas a few times. I liked them. But there was that problem in high winds.
There was a nasty accident with one on a Shell Tanker:
The aerial base was fixed on to a stub pole about five feet above the deck, by a hinged plate so that it could be lowered on occasion to reduce air draught.
Sailor sitting astride mast undid the bolts holding the whole hinge assembly instead of just the bolts holding the hinged plate. I can not remember if it was a fatality or just a near one.


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## Ron Stringer (Mar 15, 2005)

Radiomariner said:


> There was a nasty accident with one on a Shell Tanker:


Slightly off thread. MIMCo supplied stainless steel transmitting whip antennas comprising three stainless steel tubes of different internal diameters that were joined by s/s compression fittings to make a 37ft long antenna. This was attached to the superstructure of the ship by two large ceramic, stand-off insulators and clamps. In service they had a series of fractures of the upper tube, close to the joint with the middle tube. The fracture looked like a classic fatigue failure. Most commonly they occurred on the faster motor ships being built in the late 1960s and early 1970s. One such failure, on a passenger ship, occurred overnight and was only discovered when the deck crew began holystoning the wooden upper games deck and found a 12ft 'spear' embedded in it (rather like the arrows in one of those adverts for Strongbow cider).

It was assumed that the cause was vibration-induced failure (memories of the DH Comet were fresh in the minds of engineers at the time). So someone introduced an an anti-vibration mount. The incidence of failures reduced on the ships where they had earlier problems but then arose on another type of ship, VLCCs.

So we got the mechanical research boys to fit several ships with vibration monitors and another group to examine the vibration characteristics of the antenna assembly itself. The first group found that the fast motor ships where there had been failures produced high vibration levels at 11-14 Hz whereas the VLCCs' peak vibrations were at 6 - 9 Hz. 

Then we got the results of the vibration and wind-tunnel tests from the other group. The antenna had basic resonance at 11.5 Hz and, when fitted with the 'anti-vibration' mounts, of 7.2 Hz. Designed for disaster!

So we stopped selling that device and offered the D&K MAS140 instead. While we still had failures of top whips, the failed item resembled a glass-fibre fishing rod, not a lethal weapon, i.e. a 12ft by 1.5-inch, stainless steel tube or javelin. We did find the shipowners to be reluctant to opt for the D&K option - the attraction for them had been the relatively low cost of the 37ft whip, which made it a cheaper proposition than providing support structures for wire antennas, and paying overtime for crew to lower and raise the wires when needing to work cargo. The D&K mast antenna was much, much more expensive. 

So most of them chose instead to sling lousy little wires around the accomodation, barely clear of the metalwork. One owner, for a class of all-aft ships chose to provide a single attachment point on top of the signal mast, from which was rigged an inverted 'V' of wires running down to two points either side of the poop. Those on board were unhappy to discover that whilst they could get reasonable communication with radio stations abaft the beam, not a lot of radiation went ahead of them. We had reports from the R/Os that on East-West crossings of the Atlantic, they had to request course changes in order to contact GKA.

The Comrod AS9 antenna, which came along several years later, was at a more attractive price and had relatively few problems yet was possibly an even better radiator than the MAS140. It was much more widely-fitted and got good reports from R/Os.

Myself, I favoured the long, long, wire strung between two high masts and a near-as-possibly-vertical downlead. Old-fashioned but couldn't be beaten.


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## Pat Thompson (Jan 25, 2006)

Greetings,

A Dieckmann & Klapper MAS 140 Aerial, wow, must get one.


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## mikeg (Aug 24, 2006)

Ron Stringer said:


> Myself, I favoured the long, long, wire strung between two high masts and a near-as-possibly-vertical downlead. Old-fashioned but couldn't be beaten.


Couldn't agree more, it worked very well. I had far too many failures with whip antennas. The only advantage I could see for fitting whip antennas was cargo ships etc. where a wire antenna required lowering during each cargo operation.


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## Troppo (Feb 18, 2010)

I sailed with a couple of AS9s.

Very good at HF...

There was one tanker on the Aussie coast with a 'traditional' nice long main antenna.

She was about 10dB up on everyone else on 5ton (using my calibrated ear..!).


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## trotterdotpom (Apr 29, 2005)

I sailed with these aerials on "River Embley" - and "TNT Alltrans" I think. Had to replace the element twice on different ships. I think I found out what was happening to them, but I forget what it was.

Lowering the aerials took ages and was a pain in the a*rse - almost as much as finding the special spanner that was used for the job. It was large and shiny and any magpie would love it in their locker just in case it was something to do with them!

Luckily, I had the brains not to sit on the bit that I was unbolting.

John T.


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## Buoy (Nov 29, 2006)

Have a look at this one from the P&O BSL OBO 'Kildare'

http://www.shipsnostalgia.com/galle...150835/title/mas-20-mf-2fhf-antenna-i/cat/all


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## Ancient-Mariner (Mar 30, 2009)

Thanks for that link Derek.

That certainly looks like the aerial that I sailed with on the City of Durban and Alsatia and Alaunia.

Must admit that in 1978 when on my first 'solo' voyage, I joined the mv Alaunia/GSEN in Hong Kong and worked Portishead on W/T from there via Japan to Honolulu and on to Los Angeles without too much effort. A bit of panic mind, but looking back, not too much effort!

Thanks again Derek

Best Regards

Clive


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## King Ratt (Aug 23, 2005)

Treborvfr is correct. I was on MV British Forth/GRUQ in 1982. She was fitted with a D & K antenna.


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## andysk (Jun 16, 2005)

Ron Stringer said:


> ... Myself, I favoured the long, long, wire strung between two high masts and a near-as-possibly-vertical downlead. Old-fashioned but couldn't be beaten.


As far as I can remember, don't the principles of physics say exactly that ? And anything else, like the D&K, the AS9 (of which IMRC fitted many in the early 1980's), and their ilk are compromises to 'fool' the transmitter into thinking there was a 'real' long wire up there somewhere ?


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## mikeg (Aug 24, 2006)

I wonder what the main reason was for largely abandoning the inverted 'L' antenna? I can understand this where some cargo vessels where it would hamper loading/discharge and possibly white oil tankers where the antenna is above the cargo tanks (any basis in this fear?). Maybe it all comes down to marketing plus a smidge of bull*h*t baffles brains reasoning.


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## Troppo (Feb 18, 2010)

The idea was to keep the antennas away from the cargo tanks on tankers and to keep the deck clear on bulkies.

Great on HF....very poor on MF....you just can't beat wire in the air at MF...


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