# 25Mhz



## odobber6 (Mar 1, 2011)

Does anyone remember using 25mhz for ship communications
To Portisheadradio. I vaguely recall using this freq when sunspots
We’re at maximum. I sailed from 1970 to 1984.


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## Larry Bennett (Aug 28, 2005)

I don't think GKA had the allocated channels for w/t working on 25 MHz. However I do recall working ships crossband on 22/25 MHz a few times when conditions allowed, and certainly had some QSA/QRK 5/5 contacts on those frequency bands. The w/t transmitters could not be brought up outside of their designated frequencies, although the Quick-Tune R/T (synthesised) transmitters certainly could. It is possible that some R/T calls could have been handled on 25 MHz although I don't think the GKA frequencies were advertised. I will scour through my archives to see if any 25 MHz channels were officially allocated to GKA.
Larry +


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## Larry Bennett (Aug 28, 2005)

Gone through my old frequency lists - certainly no 25 MHz w/t frequencies allocated. However there was an R/T Channel - GKU25 (ITU Ch 2502) which transmitted on 26148 kHz and listened on 25073 kHz. Can't recall using it much, but it was there 'just in case'.
Larry +


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## Larry Bennett (Aug 28, 2005)

GKA R/T Frequencies sheet from 1993 showing the 25 MHz channel.


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## Shipbuilder (Jun 30, 2005)

I used 25mHz to Portishead Radio quite regularly for a time, but it was on the HF teleprinter service. I remember that even in Table Bay, the signal was so stong, it was like communicating with a UK coast station from only a few miles away. It continued for well over a year, but eventually, the signal strength faded out, and it became unuseable -


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## odobber6 (Mar 1, 2011)

*25mhz*

Thanks Larry
I guess I must have used 25mhz for some r/t calls back in seventies
And not w/t. Thanks for looking it up
Regards 
Denis


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## Baulkham Hills (Jul 11, 2008)

I seem to remember working Dan on 25 MHZ and also the Norwegian station Rogaland on W/T. and the calling frequency was also the working frequency. But I could be wrong about that.


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## hawkey01 (Mar 15, 2006)

I certainly cross banded 22/25mhz on WT a few times. You had to have a nice new ship with all the gear not an old MIMCO vessel with a Span 7 thats for sure.

Larry I did not remember having that 25mhz RT channel. Certainly never used it.
Did some odd things on the Aero/point to point with our QT3's and the rotatable aerial though.

Neville


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## King Ratt (Aug 23, 2005)

I worked an RT QSO way back in 1964 from the Indian Ocean direct to UK using a 25 Mhz frequency. I seem to remember having to send an Atel??? To Portishead to arrange this. QSO started with talking to a “tech” who patched me through to the phone number. My ship was the RFA Tidereach, the transmitter was the Marconi Type NT204 aka Naval Type 640. This had an output of 700 watts on a good day. The antenna was a tuneable whip. The synthesiser allowed any frequency desired to be selected.


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## odobber6 (Mar 1, 2011)

*25mhz*

Thank you all for responding to my post.
It was a long time ago and I was not really sure if I used 25mhz
But now I know I did.
Denis


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## Larry Bennett (Aug 28, 2005)

Shipbuilder said:


> I used 25mHz to Portishead Radio quite regularly for a time, but it was on the HF teleprinter service. I remember that even in Table Bay, the signal was so stong, it was like communicating with a UK coast station from only a few miles away. It continued for well over a year, but eventually, the signal strength faded out, and it became unuseable -


Just located a radiotelex frequency list from the 1980s which shows an RTT channel with callsign GKE8 - Portishead transmitting on 25390 kHz and receiving on 25078.8 kHz. Can't remember using that channel much but it must have been brought up when conditions allowed.

Larry +


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## IMRCSparks (Oct 1, 2007)

I notice in the frequency table provided by Larry that there is a 18/19Mhz band. When was this band introduced? I'm fairly sure it wasn't available on the transmitters that I sailed with in the 1980's. It does appear in a GMDSS frequency list that I found so maybe it's a GMDSS requirement? Seems like a good idea anyway to have something between the 16 & 22MHz bands.


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## Larry Bennett (Aug 28, 2005)

The new 18/19 MHz maritime frequencies came into effect on 1 July 1991 as a result of a band plan change at the ITU at a previous radio regulations conference (WRC-1987 perhaps). There were also changes to the 12 MHz bandplan at the same time. I do seem to remember some 12 MHz channels changing as a result of the new allocations.

Again, although GKA were allocated frequencies on 18/19 MHz I recall they were working R/T channels only, with no broadcasts or traffic lists on that band. 

Larry +


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## djringjr (Feb 11, 2008)

Just to chime in, Slidell Radio/;WNU put a 1 watt signal on their 25 MHz WT frequency, and I heard it loudly from off the southern coast of Chile near Cape Horn, they told me I was really loud, it was in 1982 and conditions were very good not like now. 

73
DR

David J. Ring, Jr. - ex Tuckerton Radio and various USMM ships.

N1EA


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## Jumbuk34 (Mar 27, 2019)

I worked GKA from Bahia Blanca South America on 22 Mc/s on South American Saint Lines St Merriel/MAOS. In desperation used A2 (MCW) and subsequently got a letter from PMG. ...Alright I know I'm naughty! 73s


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## gordonarfur (May 27, 2018)

never heard of 25mcs tried 22mcs a couple of times, never heard a dickey bird.


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## Troppo (Feb 18, 2010)

22 MHz was great at the top of the sunspot cycle....the Japanese stations were super strong on the Aussie coast.


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## tunatownshipwreck (Nov 9, 2005)

25 mhz was pretty good 1978-1982.


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## 5TT (May 3, 2008)

I definitely used 25mhz WT from the North Sea to Capetown / ZSC on more than one occasion. I'm guessing this would have been around 1980 and I remember it well because it was like he was sitting next door, really solid. On the amateur bands I've had much CW success on 28mhz in the opposite direction with just a handful of watts, amazing really, dead up there at the moment though.

= Adrian +


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## sparks69 (Dec 18, 2005)

I used it occasionally on W/T with an ST1400 Tx. You didn't need much power (5w I think was the minimum switchable ) or even an aerial connected on a couple of occasions !
Didn't last for long, only a few years, as previously mentioned.


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## sparks69 (Dec 18, 2005)

Jumbuk34 said:


> I worked GKA from Bahia Blanca South America on 22 Mc/s on South American Saint Lines St Merriel/MAOS. In desperation used A2 (MCW) and subsequently got a letter from PMG. ...Alright I know I'm naughty! 73s


I got a complete transcript of a long chat I had off the East coast of Canada to a mate I had on a Niarchos ship in the Mozzy Channel. Some Indian monitoring station picked me up. Replied with a humble letter of apology. Never heard anything else.


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## Rojjal (Mar 19, 2017)

In 1973 I had QSO on 25MHz with Rogaland Radio/LGB from east of Japan. This was R/T on A3, no fancy SSB on this NERA tx. Good conditions for about one hour and as 5TT said, like sitting next door.


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