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SAQ - An historic radio transmitter

JimB

Super Moderator
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In southern Sweden at a place called Grimeton, is an historic radio transmitter, the only remaining example of its type.

What is so special about it?
To generate the RF, instead of the usual valves or transistors, it uses an alternator. Yes, a rotating mechanical machine.
As you may expect, the frequency is rather low at 17.2kHz.

The station was built many years ago (1920s) to provide a reliable long distance communication system in conjunction with similar transmitters at other places around the world.

The transmitter at Grimeton is preserved as a museum, but the associated antenna is still used by the Swedish Navy for use on 40.4kHz.

Twice a year, the old transmitter is connected to the antenna and run up to send a short message.
The days are Alexanderson Day (in memory of the the guy who designed the alternator) which is the first Sunday in July, and Christmas Eve the 24th December.
Tomorrows transmission takes place at 08:00 UTC (GMT in disguise).
I will be up nice and early to listen for it, having heared it several times in recent years.

For more information about SAQ, have a look here:
http://en.wikipedia.org/wiki/Varberg_Radio_Station
or here:
http://www.grimeton.info/
It may appear in Swedish, but click on the Union Flag for an English vesion.

JimB
 

Brevor

Member
Thanks Jim for the info. I have seen pictures of the Grimeton alternator but I had no idea they still ran it at times. What kind of receiver are you using to receive it.
 

JimB

Super Moderator
Most Helpful Member
For a receiver I use a converter which converts 0 to 500kHz to 10.0 to 10.5Mhz, that feeds into an Elecraft K2 amateur bands transceiver.

I do have a receiver which will receive down to 10kHz directly, an Eddystone EC958. But that is a bit lacking in sensitivity doen on those frequencies.

JimB
 

rumpfy

Active Member
This is what Marconi used. No valves then.
Marconis dream to send radio signals across the Atlantic was dependent on developing higher and higher power and in the end he did it. The transmitters were built, I think, by a company which became the 'General Electric Company'.
The Titanic was the first vessel to use the 'Marconi Wireless', and this was 1912. I imagine by 1920, the world shipping fleet was intensely interested in this new invention.
 

Ramussons

Active Member
This is what Marconi used. No valves then.
Marconis dream to send radio signals across the Atlantic was dependent on developing higher and higher power and in the end he did it. The transmitters were built, I think, by a company which became the 'General Electric Company'.
The Titanic was the first vessel to use the 'Marconi Wireless', and this was 1912. I imagine by 1920, the world shipping fleet was intensely interested in this new invention.
I think that the original Marconi transmitter and that used in the Titanic was a Spark Gap Transmitter.
The Alternator technique was adopted almost a decade later.

Ramesh
 

JimB

Super Moderator
Most Helpful Member
Yes, the original Marconi system used a spark transmitter.
Hence the now little used nick name for a radio operator - "Sparks".

So, what did I hear this morning?
The signal was not as strong as I have heard it on previous occasions, to make it copyable I had to turn the receiver bandwidth down to 100hz, (very tight!).
Even then I did not read the message 100% due to a bit of fading, also maybe a problem with my temporary VLF active antenna getting battered about in the gales which we have today.

JimB
 

dr pepper

Well-Known Member
Most Helpful Member
I beleive the bbc used those at one time, they must have all been scrapped.
 

nsaspook

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Nothing historic like SAQ , but one of my old duty stations closed last year. It was a very cool place to work in the 70's. NAR was an original.
http://keysnews.com/node/42850
When I worked there I was a 'sparky', we did mainly HF work but did have VLF comms for TACAMO support
100_0340.JPG
 
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JimB

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Most Helpful Member
Interesting, sounds like it was a nice place to work.
JimB
 

cowboybob

Well-Known Member
Most Helpful Member
nsaspook,

NAV for me also. '67 to '74. ETR with a 1598 job code. Nuc fast attack (SubFlot 6) tenders. Mostly test equipment but it included all aspects of boat electroncs (DC to radar and ECM) here in Charleston. Fine duty... (war port was San Juan :cool:).
 

nsaspook

Well-Known Member
Most Helpful Member
Interesting, sounds like it was a nice place to work.
JimB
I was a Navy RM-2313/2318 Independent Duty Radioman/Communications Systems Manager. A fancy name for guys who could repair their equipment like ET's could and create/control radio network operations using that equipment.

Our 'Navy' receiver site (where I mainly worked) was at the far end of the air base next to a mangrove swamp so that was pretty dull unless you liked to fish but we had a 'sister' station in downtown Key West that ran the FBIS Annex post that a lot of us worked for after hours for extra money on the side. Life in the 70's 'Snake Bar' filled Margaritaville was a blast.
http://www.readex.com/content/foreign-broadcast-information-service-fbis-daily-reports-1941-1996
 
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