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General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc. |
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9th Nov 2017, 2:08 pm | #21 |
Dekatron
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,687
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Re: Hotel Panel Radios
Synchronised, possibly? Before November 23 1978 it was BBC Radio 2 that went out on 200kHz Long-Wave from Droitwich. Radio 4 after that date. So might 200kHz have been used as a frequency standard to keep the clock disciplined?
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Regds, Russell W. B. G4YLI. |
9th Nov 2017, 2:18 pm | #22 |
Hexode
Join Date: Oct 2016
Location: Newport, South Wales, UK.
Posts: 278
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Re: Hotel Panel Radios
Doesn't / didn't Droitwich LW carry a signal used in connection with Economy 7 and similar electricity tariffs? Perhaps the clock somehow used that to synchronise twice a day?
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9th Nov 2017, 3:07 pm | #23 |
Pentode
Join Date: Mar 2003
Location: Mansfield Woodhouse, Nottinghamshire, UK.
Posts: 216
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Re: Hotel Panel Radios
The clock was powered from the Radio 2 signal simply by rectifying it and using the DC to power the clock. The very low power demands of the clock made this possible.
Radio 2 was chosen because, back in the day, it was the only station to broadcast 24hours a day!
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9th Nov 2017, 3:22 pm | #24 |
Dekatron
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Location: Penrith, Cumbria, UK.
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Re: Hotel Panel Radios
Yes. 22.5 degree bi-phase modulation of the carrier, including clock data.
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9th Nov 2017, 3:26 pm | #25 | |
Dekatron
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Re: Hotel Panel Radios
Quote:
I can't see the BBC being so generous as to provide sufficient field strength to overcome a diode voltage drop for the abstraction of free electricity!
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9th Nov 2017, 3:32 pm | #26 |
Pentode
Join Date: Mar 2003
Location: Mansfield Woodhouse, Nottinghamshire, UK.
Posts: 216
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Re: Hotel Panel Radios
Sorry, should have been clearer. All the radio feeds to the bedhead unit were at AF, using telephone twisted pairs. The multiple Tuner/Amplifier was somewhere in the lobby in an inaccessible cupboard normally.
100V line was used for the hotel PA, but not for the audio to the bedhead units, due to having to use multiple step-down transformers and the undesireability of having 100v near the customer.
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I was so upset that I cried all the way to the chip shop. |
9th Nov 2017, 3:48 pm | #27 | |
Dekatron
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
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Re: Hotel Panel Radios
Quote:
I have stayed in several hotels recently that have PA speakers in the ceiling: never heard anything from them, though.
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9th Nov 2017, 5:06 pm | #28 |
Dekatron
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
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Re: Hotel Panel Radios
Hotel radios always make me think of Carry on Abroad
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Kevin |
9th Nov 2017, 5:39 pm | #29 | |
Dekatron
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Re: Hotel Panel Radios
Quote:
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9th Nov 2017, 7:29 pm | #30 |
Nonode
Join Date: Nov 2015
Location: Welwyn Garden City, Hertfordshire, UK.
Posts: 2,015
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Re: Hotel Panel Radios
Apologies Russell, In my neck of the woods you can power small stuff such as LCD clocks from 909kHz if you are determined enough.
Once it was R4 then R2 now R5. I used to use crystal earpiece OA81 and 33k resistor to the nearest metal object back in the day for the Archers. Now lost it's appeal. Front door knob worked well. I'm pleased I live no closer to BPK. Last edited by Jon_G4MDC; 9th Nov 2017 at 7:35 pm. |
9th Nov 2017, 8:21 pm | #31 |
Dekatron
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
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Re: Hotel Panel Radios
That sort of thing happened at Droitwich many years ago too.
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Regds, Russell W. B. G4YLI. |
13th Nov 2017, 4:36 pm | #32 |
Heptode
Join Date: Jan 2008
Location: Shrewsbury, Shropshire, UK.
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Re: Hotel Panel Radios
I used to work for The Rank Organistion, in the Top Rank Television division.
I used to install these systems, amongst other things. We had an engineering agreement with Rediffusion, and used a similar system to them, but on different frequencies for TV distribution in hotels. As well as distributing the TV signals at what was known as 'System Frequency', the audio was carried on the same pairs as the RF, at a nominal 50v. This works the same as tradititional 100v line audio distribution, but the lower level was used so as not to cook the vision inserts.(Attenuators/ filter chokes etc). We fitted Bed-head panels, some with TV & some with only radio. The unit was simply a selector switch system, accessing each audio /vision pair. This was then fed to the bed-head speaker, or TV speaker, which incorporated a 50v line matching transformer. There were often local 'In-house' generated audio programmes, as well as TV replayed from banks of U-Matic recorders. We used to fit these all over the world, as well as hotels in the U.K. David. Last edited by Vintage Engr; 13th Nov 2017 at 4:37 pm. Reason: Typo. |
17th Nov 2017, 9:48 pm | #33 |
Pentode
Join Date: Sep 2009
Location: Dundee, UK.
Posts: 158
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Re: Hotel Panel Radios
A company called Sound Diffusion had a system in a local hotel in the 50's, two radio chassis Home and Light programmes feeding units in the bedrooms.
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18th Nov 2017, 11:44 am | #34 |
Tetrode
Join Date: Jan 2015
Location: St Jean d'Angely, Charente-Maritime, France
Posts: 81
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Re: Hotel Panel Radios
Attached are photos of the system I built to enable me to lisen to British radio here in the south west of France.
The system comprises a quattro LNB on the dish feeding a 16 outlet distribution amplifier. This feeds five satellite receivers (only four in the picture;one is faulty). These feed a home built five-channel power amplifier. The signals are fed at 100 volts using telephone twisted pair to speaker units (the one shown is in my bedroom along with my work boots). The receivers run continually but the power amp is switched on by a DC phantom across the speaker feeds. When a station is selected, a DC path to earth is formed which operates a relay to power the amplifiers. The satellite dish also feeds televisions in various rooms. |
30th Dec 2017, 11:10 pm | #35 |
Heptode
Join Date: Oct 2006
Location: Leeds, West Yorkshire, UK.
Posts: 597
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Re: Hotel Panel Radios
This thread reminds me of the 'radio' installed at our primary school in Leeds. The school itself was built circa 1950 and the radio consisted of (externally, at least) a ceiling-mounted loudspeaker grille in each classroom (several in the hall) with a simple toggle switch for on/off. There was no obvious volume control, tuning or station selection. As I recall, all we ever heard was the Radio 4 Schools Service which was probably on LW as this was 1975 through to 1980. So I don't know if there was a genuine radio receiver in the school, a Rediffusion-style cable system or a Leeds City Council network using GPO lines. Interesting times.
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5th Jun 2018, 9:41 pm | #36 |
Heptode
Join Date: Apr 2011
Location: Edinburgh, UK.
Posts: 805
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Re: Hotel Panel Radios
Group of 4 which sold recently.
Last edited by AC/HL; 5th Jun 2018 at 11:53 pm. Reason: Dead link removed |
10th Jun 2018, 8:36 pm | #37 |
Dekatron
Join Date: Oct 2003
Location: Southport Lancashire, UK.
Posts: 3,233
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Re: Hotel Panel Radios
I stayed in holiday hotels in the Isle of Man in the 1970s quite often. They had these radios in the rooms. One of the buttons was an intercom to reception.
When the tourist industry collapsed there I went to the demolition site of one of these hotels and there was a skip full of these sets including the master receiver. I considered rescuing them but left them to go to landfill. I just rescued a tile form one of the bathrooms as a memento.
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Paul |
20th Jun 2018, 9:17 pm | #38 |
Heptode
Join Date: Jan 2009
Location: West Lothian, UK.
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Re: Hotel Panel Radios
Daughter emailed the pic of one in her hotel today. I looked on the web to get a wider view of the rooms in that hotel.
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George |