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I started out with a BTH crystal set in my early days then moved on to short wave radio .In the 50s we would place a couple of receivers side by side and the time signals from around the World would always vary.

Short Wave is a bit different as firstly it is World Wide and secondly it is notoriously unreliabe in signal propagation.

It is very easy with SW to pick up stations broadcasting time signals for CET (central European), EST (Eastern States Time) and many other time zones.

Having said that, and to avoid confusion, <_<:unsure: , many stations always gave out broadcast time in UT (Universal Time) or GMT (Grenwich Mean Time).

All sorts of wierd things happened to SW signals as they bounced around the Appleton and Heavyside layers of the ionosphere which could cause delays.

Interestingly, some of the very powerful transmitters like Radio Moscow could, given the right ionospheric conditions, create a "round the world echo" where the same signal was picked up again, albeit weaker, about a seventh of a second later, after going completely around the world! (Is that an echo then vox or a reverberation?)

The only time signal I ever relied on from SW radio frequencies was the BBC World Service.

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Does anyone remember the late 50s on Saturday mornings, if a VHF radio was placed near to the T V, the Light programe on one and BBC on the other you got a good imitation of stereo sound. Not exactly high tech, but exiting times all the same. W/E.

I don't remember it from the 1950's W/E (I thought VHF FM radio on Band II (88 - 108 MHz) only really started with local radio in the 1960's anyway.

I do remember however, first getting REAL stereo on TV in the late 60's / early 70's using exactly this principle.

I watched on TV, in black and white as it happens although it may have been broadcast in colour before we had a colour TV, a series of classical music concerts in which the BBC experimented with stereo sound as TV sound was NOT stereo at the time.

The programme itself was broadcast on BBC 2 TV, a channel which at the time was considered "new" and that broadcast "highbrow" programmes like concerts, and the sound broadcast with it was just one of the channels, - left channel if I remember correctly.

Simutaneously with this broadcast, BBC Radio 3 on VHF radio, a radio station also associated with the broadcast of classical music, was transmitting just the right hand channel of sound for the same concert.

I remember setting this up to try out stereo TV sound but not being too impressed with the results as, although the sound was stereo, it did not match the images very well as the screen was always close to the left hand speaker and it was difficult to place the radio to get the right hand speaker in the correct place. However, it did work.

..and I don't remember any problems with sound delays between the 2 channels either.

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I don't remember it from the 1950's W/E (I thought VHF FM radio on Band II (88 - 108 MHz) only really started with local radio in the 1960's anyway.

Could have been as early as 1958 in Sheffield !. Our scoutmaster Brian Clayton had one of the first VHF sets. A patrol at a time would go to his house to listen to the VHF police messages. W/E.

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Could have been as early as 1958 in Sheffield !. Our scoutmaster Brian Clayton had one of the first VHF sets. A patrol at a time would go to his house to listen to the VHF police messages. W/E.

I remember now.

In the early days of VHF radio Band II wasn't just used by broadcast radio stations as it is today throughout its entire 88 - 108 MHz spectrum. The lower end, 88 to about 95-ish MHz was radio stations and the upper bit, certainly the bit above 100MHz was used by police and other emergency and public service units for mobile communications.

You don't get that on VHF anymore. I assume the police have moved onto more secure frequencies where criminals can't listen in to what their next move is going to be.

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I remember now.

In the early days of VHF radio Band II wasn't just used by broadcast radio stations as it is today throughout its entire 88 - 108 MHz spectrum. The lower end, 88 to about 95-ish MHz was radio stations and the upper bit, certainly the bit above 100MHz was used by police and other emergency and public service units for mobile communications.

You don't get that on VHF anymore. I assume the police have moved onto more secure frequencies where criminals can't listen in to what their next move is going to be.

The police and other emergency services now use the TETRA communications network which is a digital encrypted network working at around 400 Mhz.

You can find the base-stations as well as the mobile phone base-stations at http://www.sitefinder.ofcom.org.uk/

HD

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I remember now.

In the early days of VHF radio Band II wasn't just used by broadcast radio stations as it is today throughout its entire 88 - 108 MHz spectrum. The lower end, 88 to about 95-ish MHz was radio stations and the upper bit, certainly the bit above 100MHz was used by police and other emergency and public service units for mobile communications.

You don't get that on VHF anymore. I assume the police have moved onto more secure frequencies where criminals can't listen in to what their next move is going to be.

I remember listening (accidently) to a police transmission during a boring night-shift in 1970.

It concerned a bloke who had stolen a bin waggon and was causing mayhem all over South Yorkshire. We listened enchanted as he was followed by about 10 police vehicles and every time one tried to get in front he barged them out of the way. This was in the days before the "Stinger". The chase went on for about an hour and the senior officer in the control room eventually asked if some-one could get close enough to "coit a brick through his window".

Eventually he ran off a road at a bend and set off across a field to be brought down by dogs.

HD

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The police and other emergency services now use the TETRA communications network which is a digital encrypted network working at around 400 Mhz.

You can find the base-stations as well as the mobile phone base-stations at http://www.sitefinder.ofcom.org.uk/

HD

400MHz,

Now that is, to an old 'un like me, an out of band UHF frequency just below the UHF Band IV and Band V frequencies which are the UHF TV channels 21 to 68. I think channel 21 starts at around 470 MHz.

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I remember listening (accidently) to a police transmission during a boring night-shift in 1970.

It concerned a bloke who had stolen a bin waggon and was causing mayhem all over South Yorkshire. We listened enchanted as he was followed by about 10 police vehicles and every time one tried to get in front he barged them out of the way. This was in the days before the "Stinger". The chase went on for about an hour and the senior officer in the control room eventually asked if some-one could get close enough to "coit a brick through his window".

Eventually he ran off a road at a bend and set off across a field to be brought down by dogs.

HD

He stole a bin wagon!!! :blink:

What would posses anyone to want to do that :unsure:

"Was there owt in it worth nicking?"

"No, - just a load of old rubbish in the back"

Incidentally, the spelling of wagon with 2 g's (waggon) is the accepted trade mark of the Sentinel Steam Waggon Company.

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The senior officer in the control room eventually asked if some-one could get close enough to "coit a brick through his window".

When my dad was a painter for the Corporation (Markets dept.) he frequently had to work nights so that the building could be used normally during the day.

Due to the stock on the market premises there were also "night security officers" who policed the place against possible robberies.

One night my dad witnessed a robbery in which some criminals had broke in and loaded a van up with stolen goods but were then spotted by security.

The crooks made off in the van thinking they had outwitted the guard but he radioed his mates at the end of the car park saying "stop that van, they've nicked stuff"

His mate DID stop the van, - by picking up a brick and putting it through their windscreen as they drove past :o

They lost control of the vehicle and crashed then were arrested (unharmed as it happened) before they could leg it.

I don't suppose they would let the Police do it these days but I think the brick through the windscreen could be more effective, if not as safe, as the Stinger.

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400MHz,

Now that is, to an old 'un like me, an out of band UHF frequency just below the UHF Band IV and Band V frequencies which are the UHF TV channels 21 to 68. I think channel 21 starts at around 470 MHz.

According to Wikiwhotsits TETRA stands for Terrestrial Trunked Radio and is on 380-395 Mhz, just below the 70 cm Ham radio band.

HD

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I can well see that there would be a time delay, but, particularly for News at Ten that delay would create a problem.

At the end of the programme Trevor McDonald says something like "We now go over to our local newsrooms for the regional news and weather"

After this the local news and weather teams pass back to News at Ten for Trevors "..and finally" item and the National weather forcast.

A 2 second delay at regional transmitters would certainly create synchronisation problems in doing this.

It was in the days of Reginald Bosanquet. The delay was definately there, it also happened with Coronation St as I remember my children asking why their friends next door got their programmes before we d[d. My answer was always, mum was late paying the T V licence ! W/E.

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According to Wikiwhotsits TETRA stands for Terrestrial Trunked Radio and is on 380-395 Mhz, just below the 70 cm Ham radio band.

HD

70 cm band <_<

Being a bit of a shortwave DX-er my knowledge of amateur radio bands is limited to the hf shortwave bands, - anything above 30MHz is off the end of my scale so the highest frequency band I will have listened to is the 10 metre band.

I know the hams have a 2 metre VHF band (144MHz) which is very popular with them, but 70 cm, - no, not used that one.

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It was in the days of Reginald Bosanquet. The delay was definately there, it also happened with Coronation St as I remember my children asking why their friends next door got their programmes before we d[d. My answer was always, mum was late paying the T V licence ! W/E.

Reginald Bosanquet :huh:

Must be more than 20 years ago then W/E

I seem to remember Reginald was frequently drunk while presenting the news, - perhaps that introduced yet another "delay" in the transmission lol

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70 cm band <_<

Being a bit of a shortwave DX-er my knowledge of amateur radio bands is limited to the hf shortwave bands, - anything above 30MHz is off the end of my scale so the highest frequency band I will have listened to is the 10 metre band.

I know the hams have a 2 metre VHF band (144MHz) which is very popular with them, but 70 cm, - no, not used that one.

I understand 70 cm is very popular for mobile operation, much of the equipment in use is dual band 2m/70cm.

HD

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I understand 70 cm is very popular for mobile operation, much of the equipment in use is dual band 2m/70cm.

HD

The RSGB (Radio Society of Great Britain) have details of all the currently used amateur band here

RSGB amateur radio bands

They start in the long wave at 136kHZ and go all the way up to 250Ghz

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Still there and still at Dinner time

Unless you go round the other side where you suddenly "time travel" back to about 5 past 9

*disappointed face*

five past nine? not five-and twenty-past, then? :(

*disappointed*

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Could have been as early as 1958 in Sheffield !. Our scoutmaster Brian Clayton had one of the first VHF sets. A patrol at a time would go to his house to listen to the VHF police messages. W/E.

When I lived at Manor Top, we were near to the Communications aerial near the TA centre. When the loudspeakers on my hi-fi were switched on but not playing anything , you could hear the police/emergency radio conversations through the speakers.

We had a little toerag, a few doors up from us, who loved "TWOCC"ing, and it used to amuse me and my ex hubby to listen into the police giving a running commentary whilst they were in pursuit of this little so-and-so.

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*cough*...

not that we'd do anything illegal, like listening in to emergency services' broadcasts.....

*cough, cough*

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When I lived at Manor Top, we were near to the Communications aerial near the TA centre. When the loudspeakers on my hi-fi were switched on but not playing anything , you could hear the police/emergency radio conversations through the speakers.

We used to get a lot of spurious signals that could be received like this or at unexpected places on the radio dial.

Never knew where these public services / walkie-talkie signals were coming from and never thought of the Manor Top mast.

I do know we got cross channel interference from the old cable TV (Sheffield Cable) whose cables ran along the guttering soffits from house to house on the Arbourthorne.

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When I lived at Manor Top, we were near to the Communications aerial near the TA centre. When the loudspeakers on my hi-fi were switched on but not playing anything , you could hear the police/emergency radio conversations through the speakers.

We had a little toerag, a few doors up from us, who loved "TWOCC"ing, and it used to amuse me and my ex hubby to listen into the police giving a running commentary whilst they were in pursuit of this little so-and-so.

When we first lived at Crookes on the town side we used to hear the ticking sound from the Russian "over the horizon" radar ( Woodpecker) from my stereo loudspeakers when the system was switched of and unplugged. The only way to stop the noise was to unplug the speakers. The outlook from the house faced towards the east with no high ground until the Urals, (cue Leonard Rossiter).

The pulses were picked up by the speaker wiring and de-modulated by the output transistor non-linearity in the amplifier. The noise was quite noticable when you were sat quiet. My next amplifier had speaker selection switches and I used to leave those off. Eventually the system was shut down.

HD

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I do know we got cross channel interference from the old cable TV (Sheffield Cable) whose cables ran along the guttering soffits from house to house on the Arbourthorne.

In our part of Sheffield the cable company was called British Relay Wireless (BRW)

The signal was sent over multiple twisted pairs at a frequency of 3.75 Mhz. This used to cause problems for radio hams as it coincided with the 80 meter band. We had a BRW TV at one point and the cross-talk between channels meant you could keep an ear on the other channel you weren't watching.

HD

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In our part of Sheffield the cable company was called British Relay Wireless (BRW)

The signal was sent over multiple twisted pairs at a frequency of 3.75 Mhz. This used to cause problems for radio hams as it coincided with the 80 meter band. We had a BRW TV at one point and the cross-talk between channels meant you could keep an ear on the other channel you weren't watching.

HD

It probably was called British Wireless Relay hilldweller, it was probably only us that referred to it as Sheffield Cable.

I seem to remember from my SW radio days, where my long wire inverted L aeriel went out of my bedroom window, up to the soffit and was supported by going round the BWR Sheffield cable (so it was probably inductively coupled to it as well) before heading off down the garden to a laburnum tree at the bottom, that 3.75 MHz signal was full of unfiltered harmonics.

Fundamental (3.75MHz) interferes with ham 80mb

1st. harmonic (7.5MHz) interferes with ham 40mb / broadcast 41mb

2nd harmonic (15MHz) interferes with ham 20mb / broadcast 19mb

3rd harmonic (30MHz) interferes with ham 10mb

So basically it messed up a large proportion of the short wavebands.

Further to this, as the signal was also carrying video information it had a fairly broad bandwidth as well so interfered with whole areas of each band and not just individual frequencies.

Now if a radio ham had caused that much RTI (interference)they would be in breech of their licence regulations and could expect trouble from the Ministry of Posts and Telecommunications. :o

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When we first lived at Crookes on the town side we used to hear the ticking sound from the Russian "over the horizon" radar ( Woodpecker) from my stereo loudspeakers when the system was switched of and unplugged. The only way to stop the noise was to unplug the speakers. The outlook from the house faced towards the east with no high ground until the Urals, (cue Leonard Rossiter).

The pulses were picked up by the speaker wiring and de-modulated by the output transistor non-linearity in the amplifier. The noise was quite noticable when you were sat quiet. My next amplifier had speaker selection switches and I used to leave those off. Eventually the system was shut down.

HD

Gosh, you must have been really high up, then, Hilldweller!

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Gosh, you must have been really high up, then, Hilldweller!

It's rather weird but at that location the 600 feet above sea level contour ran through the garden. On a very clear day we could see the cranes at Goole Docks. Our next house at the other side of Crookes was precisely on the 700 foot contour and we could see the centre of Wakefield. Then to put the cap-kneb on it our present home at Lodge Moor is on the 900 feet contour. Our last bungalow at Hallam Head was at 975 feet.

We must like high living.

HD

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It probably was called British Wireless Relay hilldweller, it was probably only us that referred to it as Sheffield Cable.

I seem to remember from my SW radio days, where my long wire inverted L aeriel went out of my bedroom window, up to the soffit and was supported by going round the BWR Sheffield cable (so it was probably inductively coupled to it as well) before heading off down the garden to a laburnum tree at the bottom, that 3.75 MHz signal was full of unfiltered harmonics.

Fundamental (3.75MHz) interferes with ham 80mb

1st. harmonic (7.5MHz) interferes with ham 40mb / broadcast 41mb

2nd harmonic (15MHz) interferes with ham 20mb / broadcast 19mb

3rd harmonic (30MHz) interferes with ham 10mb

So basically it messed up a large proportion of the short wavebands.

Further to this, as the signal was also carrying video information it had a fairly broad bandwidth as well so interfered with whole areas of each band and not just individual frequencies.

Now if a radio ham had caused that much RTI (interference)they would be in breech of their licence regulations and could expect trouble from the Ministry of Posts and Telecommunications. :o

The receiving station for the Hillsborough and Walkley areas was situated on top of the Bole Hills off Northfield Road. The cable infrastructure must have cost a fortune and the legal bill in obtaining consents to attach cables to buildings would have been considerable.

On our street one of the freeholders wouldn't give consent and they ran the cable up the neighbours roof, attached a MASSIVE bracket to the chimney stack, then ran the cable to a similar bracket across the street, then back down their roof. They then ran a couple of houses up on the other side, then repeated the exercise to regain the original run on our side. The cables, brackets and catenaries were quite thick and looked a mess especially at road junctions.

They eventually operated a pay-to-view service for a few years and when it finished the scrap additional control boxes finished up at Bardwells. They comprised mainly electro-mechanical bits like motors and relays and didn't really have any practical use.

HD

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