Non-standard supply voltages, 1966

[PBC_1966]

From the Electricity Supply Handbook, 1966, I thought this might be of interest to some.

A list of places in the U.K. which still had mains supplies other than 240, 240/415, 240/480V a.c. (or 230 et al in Northern Ireland). The list also has few entries from the Irish Republic.

Note also how many d.c. supplies were still in use - Mostly in the London area, but a few elsewhere.

 

[OwainDIYer]

DC supplies preferred for lift motors?

 

[Taylortwocities]

One for Winston to treasure, methinks

 

[JBR]

I'm surprised how many DC supplies were present as late as 1966, bearing in mind how many things are designed for AC use. Does this mean that such things as televisions (and I believe that colour television was only a couple of years away), domestic appliances with motors and, of course, mains powered clocks were designed to work on DC?

 

[PBC_1966]

DC supplies preferred for lift motors?

That may well have been a big concern for keeping d.c. supplies available in some areas, where they were one of the early users of power, especially given the types of city districts which had d.c. mains made available early on. I believe that in London the LEB maintained limited d.c. supplies for many of the newspaper publishers in Fleet St. for their printing presses well into the 1970's if not later, even after everyone else was converted to a.c. Similar sorts of things happened in some of the big American cities.

 

[PBC_1966]

Does this mean that such things as televisions (and I believe that colour television was only a couple of years away), domestic appliances with motors and, of course, mains powered clocks were designed to work on DC?

Many TV sets and valve radios of the 1960's were "live chassis" AC/DC models which would work on either, although AC-only models were also in use. A lof of common household devices, such a vacuum cleaners, drills etc. used universal motors which would also run on either, but most clocks used synchronous motors which would work only on AC, as would many record-players and tape recorders.

Anyone stuck with a DC supply tended to have more limited choices as time went on. What the list above doesn't indicate is in which of those districts the d.c. supply was the only thing available to certain homes, or whether most/all homes were already on the a.c. systems and the d.c. was maintained for specific purposes, as mentioned above.

And yes, color television in Britain started officially in 1967 on BBC-2, although there had been trials since the 1950's.

 

[Taylortwocities]

And yes, color television in Britain started officially in 1967 on BBC-2, although there had been trials since the 1950's.

No it didn't. Over here, we started colour television

 

[bernardgreen]

Britian used the PAL system ( Phase Alternate Line ) to transmit colour information on top of the black and white signal. The Americans used the NTSC system ( National Televison Standards Committee ?? ) which suffered from phase shift in the colour information. It was more frequently refered to as Never Twice Same Colour. Watching tennis played on grass that changed from green to yellowy orange when a plane flew overhead was clear proof that anything designed by a committee would not be the best.

PAL also suffered from phase shift but as the phase was alternated on adjacent lines the effect was cancelled out on the screen and in the wiewers eyes. If you looked at the screen very closely on a sharply focus TV green grass was alternate lines of yellow and blue when a plane affected the signal

 

[ban-all-sheds]

Britian used the PAL system ( Phase Alternate Line ) to transmit colour information on top of the black and white signal. The Americans used the NTSC system ( National Televison Standards Committee ?? ) which suffered from phase shift in the colour information. It was more frequently refered to as Never Twice Same Colour.

Don't forget the French SECAM - System Essentially Contrary to the American Method.

 

[winston1]

PAL also suffered from phase shift but as the phase was alternated on adjacent lines the effect was cancelled out on the screen and in the wiewers eyes. If you looked at the screen very closely on a sharply focus TV green grass was alternate lines of yellow and blue when a plane affected the signal

That only applies to "simple PAL" used by some Japanese manufacturers to get around paying for the PAL patents. Sony were the biggest culprit. A proper PAL receiver contains a delay line to electronically average the colour phase over two lines. This gives a very slight reduction in saturation which is completely unnoticeable, but maintains the correct colour.

 

[ericmark]

Llwyngwril was running of DC 110 volt quite late, I think it changed after 1966, but not 100% it was a single village and some outlying farms so quite a small area. The residents were finding it hard to get 110 volt DC equipment and were thankful when it changed.

25 March 1925 was first demonstration of colour TV in UK. November 1929 was first BBC colour transmission and 3 November 1936 started regular transmissions. In February 1937, due in part to a disastrous fire in the Baird facilities at Crystal Palace it stopped and we moved over to the cathode ray tube. We then had to wait until the 3rd March 1966 before colour TV was again transmitted. By mid 1968, nearly every BBC2 programme was in colour. Six months later, colour came to BBC1.

As to lifts seem to remember Manchester's Hydraulic Power system was a public hydraulic power network supplying energy across the city of Manchester via a system of high-pressure water pipes from three pumping stations from 1894 until 1972. The system, which provided a cleaner and more compact alternative to steam engines, was used to power workshop machinery, lifts, cranes and a large number of cotton baling presses in warehouses as it was particularly useful for processes that required intermittent power. It was used to wind Manchester Town Hall clock, pump the organ at Manchester Cathedral and raise the safety curtain at Manchester Opera House in Quay Street.

Not DC motors.

 

[PBC_1966]

The Americans used the NTSC system ( National Televison Standards Committee ?? )

National Television System Committee.

That only applies to "simple PAL" used by some Japanese manufacturers to get around paying for the PAL patents. Sony were the biggest culprit. A proper PAL receiver contains a delay line to electronically average the colour phase over two lines. This gives a very slight reduction in saturation which is completely unnoticeable, but maintains the correct colour.

And as it has been mentioned already, SECAM also employed a delay line arrangement, not for compensating for phase errors as with PAL but because it transmitted the R-Y and B-Y color difference signals only alternate lines, the output from the delay line being used to provide the "missing" signal in each case on the intervening lines. Both NTSC and PAL transmit both signals on every line using quadrature modulation (although NTSC's I & Q signals are phase shifted rather than being "pure" R-Y & B-Y).

In February 1937, due in part to a disastrous fire in the Baird facilities at Crystal Palace it stopped and we moved over to the cathode ray tube. We then had to wait until the 3rd March 1966 before colour TV was again transmitted.

In between those dates, the BBC did make some trial color broadcasts around the 1956-1957 time frame, adapting the NTSC system somewhat to fit in with British 405-line standards. As it turned out, of course, the U.K. never did get color on 405-lines/VHF, since by the time any official decision was made the 625-line standard on UHF had already been adopted. The decision to go with PAL wasn't made until 1966.

Ireland did get PAL color on VHF because it had already adopted the 625-line standard for VHF transmissions right from the start of TV there (which was rather late, at the end of 1961). Only a handful of transmitters in the north and east of the Republic were ever 405-line, set up as a compromise for those viewers who already had VHF/405-only TV sets to receive British broadcasts from Northern Ireland or from across the Irish Sea.

 

[JBR]

It was used to wind Manchester Town Hall clock, pump the organ at Manchester Cathedral and raise the safety curtain at Manchester Opera House in Quay Street.

Yes, indeed. Just a small addendum: mains water power was used to drive organ blowers in many locations, York Minster was one although, apparently, the clanking of the pumps was considered to be too loud.

 

[ericmark]

I remember being given an old TV set. Found the mains dropper was broken measured the resistance and it was the same as the iron and toaster so instead of the resistor I had a 13A socket and would plug the iron into the TV as a dropper. Had to remember to turn heat to max or it would stop working when the thermostat clicked in.

Since it used mains droppers instead of transformers I would assume it would have worked just as well with DC as AC maybe this was why droppers were used? My TV now states 220 ~ 240 volt AC 50 Hz my mothers states 100 ~ 240 volt 50/60 Hz AC I was surprised I thought with a switch mode power supply they would have worked on DC?

 

[PBC_1966]

Since it used mains droppers instead of transformers I would assume it would have worked just as well with DC as AC maybe this was why droppers were used?

Most of the old live-chassis TV sets had the valve heaters wired in series across the supply and used a half-wave rectifier to provide the H.T., with series droppers where necessary, precisely so that they could be used on either AC or DC. On AC you could (with a 3-pin plug) make sure it was connected so that the chassis was on the neutral, but with DC supplies the chassis had to go to whichever side of the supply was the negative, regardless of whether that was the earthed side or not. So with the supply cord to the set coded red & black, if you were in a DC house fed from the negative outer, you would actually have to wire black to L and red to N in the plug for it to work.

My TV now states 220 ~ 240 volt AC 50 Hz my mothers states 100 ~ 240 volt 50/60 Hz AC I was surprised I thought with a switch mode power supply they would have worked on DC?

They probably don't even consider the possibility of running on DC these days. And the main switch on the set might not be rated for DC either.