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I am starting a new thread for the remarks made by Ron Stringer on "The writing on the wall" thread. I think the comments deserve their own thread.
As you know the QE2 had a remote transmitter room ( locker !) with 4 main transmitters. 3 of these were STC ST1430 HF 1kw self tuning transmitters. As I understand they as used by the Swedish military and possibly never certified for marine use. That said, they were good transmitters and never caused problems - except when used on the wire aerials. The self tuning of one would effect the tune of another already working and there was no provision for it to automatically retune, it would just drop right back in power ! The fault was the wire aerials too close together. As you know the ship was not supposed to have wire aerials but rely on notch aerials, so the wires had to be mounted close together so as not to be seen !
The other main transmitter was an IMR 1kw normal marine MF/HF transmitter that had been modified for remote MF tuning with servos mounted externally. Tuning the transmitter remotely was dreadful and took a while for a simple MF frequency change !
What is not so well know is that the remote transmitter room was actually the "official" radio room. To operate from the official radio room you had to go along to the transmiter room - a 5 minute walk along half the length of the ship and up about 3 decks. You then removed all the servos from the IMR transmitter and operated it normally. I am not even certain there was a main receiver in the transmitter room but were supposed to remove one from a rack in the normal radio room and carry it to the transmitter room !
I do think parts of the IMR design of the radio room left a lot to be desired !
I do know that planning for remote transmitters does cause many problems - I have had similar problems planning new radio rooms for stations in Antarctica. It would have been so easy to use marine equipment locally if you only operate one transmitter/receiver at a time. If you want to operate multiple 1kw transmitters as I did in Antarctica many years later - and as the QE2 needed in 1968 then you have problems finding suitable equipment. QE2 had the additional problem of having to have remote controlled MF equipment capable of operation from 410 to 512 khz. Coast stations remote MF equipment did not have to do this.
I wonder how MIMCO would have solved the problem of a QE2 fitout in 1968. I suspect they would also have gone for self tuning remote 1kw HF transmitters also. However what would they have used for a main remotely controlled marine approved MF transmitter ? It could not be located in the radio office as the receivers were there - remember this is 1968 and remotely tuned synthesised receivers were not common like they are now ! Maybe Marconi made a suitable MF remote transmitter at the time for the Royal Navy - although I suspect the RN would have used local MF transmitters located in the radio office.
In retrospect I think IMR were not proud of their MF solution, it was heath-robinsonish and would have used another marine approved transmitter had it been available.
All the best
Roger
You make a very interesting comment about your amazement that the ship ever passed survey. You are not the only one. I remember very clearly a number of radio surveyors coming on board and going away scratching there heads and saying "this does not seem right" !
As you know the QE2 had a remote transmitter room ( locker !) with 4 main transmitters. 3 of these were STC ST1430 HF 1kw self tuning transmitters. As I understand they as used by the Swedish military and possibly never certified for marine use. That said, they were good transmitters and never caused problems - except when used on the wire aerials. The self tuning of one would effect the tune of another already working and there was no provision for it to automatically retune, it would just drop right back in power ! The fault was the wire aerials too close together. As you know the ship was not supposed to have wire aerials but rely on notch aerials, so the wires had to be mounted close together so as not to be seen !
The other main transmitter was an IMR 1kw normal marine MF/HF transmitter that had been modified for remote MF tuning with servos mounted externally. Tuning the transmitter remotely was dreadful and took a while for a simple MF frequency change !
What is not so well know is that the remote transmitter room was actually the "official" radio room. To operate from the official radio room you had to go along to the transmiter room - a 5 minute walk along half the length of the ship and up about 3 decks. You then removed all the servos from the IMR transmitter and operated it normally. I am not even certain there was a main receiver in the transmitter room but were supposed to remove one from a rack in the normal radio room and carry it to the transmitter room !
I do think parts of the IMR design of the radio room left a lot to be desired !
I do know that planning for remote transmitters does cause many problems - I have had similar problems planning new radio rooms for stations in Antarctica. It would have been so easy to use marine equipment locally if you only operate one transmitter/receiver at a time. If you want to operate multiple 1kw transmitters as I did in Antarctica many years later - and as the QE2 needed in 1968 then you have problems finding suitable equipment. QE2 had the additional problem of having to have remote controlled MF equipment capable of operation from 410 to 512 khz. Coast stations remote MF equipment did not have to do this.
I wonder how MIMCO would have solved the problem of a QE2 fitout in 1968. I suspect they would also have gone for self tuning remote 1kw HF transmitters also. However what would they have used for a main remotely controlled marine approved MF transmitter ? It could not be located in the radio office as the receivers were there - remember this is 1968 and remotely tuned synthesised receivers were not common like they are now ! Maybe Marconi made a suitable MF remote transmitter at the time for the Royal Navy - although I suspect the RN would have used local MF transmitters located in the radio office.
In retrospect I think IMR were not proud of their MF solution, it was heath-robinsonish and would have used another marine approved transmitter had it been available.
All the best
Roger
