Audio Precision System One Dual Domani Measuirement Systems

How many channels and at what signal levels did you try it on? We had seven six port combiners in two groups of eight for a 36 channel headend. The six outputs were combined in the seventh unit and amplified before leaving the building. It did help in some installations, where HSP were used for off air processing and for stations who would push their character generators to over 100% modulation from affecting other channels.

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You can't have a sense of humor, if you have no sense.

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Does it matter? Were you alive to see it, and in their service area? I wasn't and I wasn't. I was a TV broadcast engineer at three US TV stations from the early '70s to the late '80s. I started with monochrome and film, and ended up with 1" Sony color VTRS & RCA TK46A cameras feeding a 5 MW EIRP antenna 1700+ feet AAT.

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You can't have a sense of humor, if you have no sense.

Perhaps you just like to start fights. We wanted to use Wiremold Plugmold type steel power strips made for relay racks, but the ESA wanted individual outlets mounted on metal boxes inside the racks which wasted a lot of space so we used what they shipped us.

I never said it did. That's why I thought that it was funny to see them buy a bunch of them, and walk away like they had won a huge prize.

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You can't have a sense of humor, if you have no sense.

In message , Terry Casey writes

Same lot, in the land of the concrete cows and a thousand roundabouts. ;o))

Ah yes. That's certainly one of the reasons for using a weird reference frequency. I recall that certain systems insisted that the four set-top bypass channels had to be close to the standard off-air broadcast channels, because some TV sets would not tune to anything but these. Almost certainly this is what I was involved in.

But wasn't it at the same place which ingeniously used a not-quite-8MHz comb reference which was actually derived from one of the UHF off-air channels? As the headend equipment was largely supplied by the 'other' company, I doubt if I would have been involved with tinkering with it (although I'm pretty sure that I did swap one or two of the modulator SAW filters because of the problems which arose when NICAM started). Maybe 'my' comb generator was a replacement.

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Ian

In message , Michael A. Terrell writes

I'm sure that that the point being made was that despite all that had happened to Britain since 1939, we were now picking up the pieces, continuing where we had left off, and getting back to business as usual. Even if it didn't quite happen as reported, there is no doubt that the popular version of the story would have been good for moral.

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Ian

They would have to be very unusual TV sets!

It was more likely to be, in the case of Westminster, that, when CATV systems rarely went above 600MHz, there was nowhere else to put them, coupled with the fact that the off-air channels were left clear, so it was convenient utilise to this for the n + 2 arrangement by straddling the otherwise blank off-air allocation.

A comb of 7.988636364MHz would allow E25, E27, E29 and E31 to be used with +/-34kHz error (off-airs being 23, 26, 30 & 33)

Of course, this was all long before the Channel 5 debacle - I can't see a way of interleaving 5 channels around Crystal Palace without involving the allegedly taboo n + 5 scenario - although I've never seen a problem with any set I used directly connected to a CATV network

Well, dividing E26 by 64 or E30 by 68 would do the trick. I based my comb frequency on E28, being the centre channel but an off-air lock would certainly produce a very stable result, and the offsets would still be reasonable - +58/-11kHz or +11/-58kHz, depending on choice of off air channel.

My involvement with the Westminster system was at the time of the DTV roll-out (or possibly Broadband Internet, I can't remember which) which coincided with the transfer of the system from BT to ntl, so I never saw the BT headend but I did see the documentation related to it, complete with frequency details.

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Terry

In message , Terry Casey writes

I don't know about 'unusual', but they were a problem. I think there were only couple of budget brands which only tuned 'spot-on' to the UHF channels (xxx.25MHz, in 8MHz steps). One might ask indeed "Why would you need them to do otherwise?" Of course, even our cable set-top boxes could normally only tune in 125kHz steps, but at least that got you to within +/-63kHz of the correct frequency - and that was more than close enough.

Sets generally seemed to improve a lot in later years. I think that the change of IF from 39.5MHz to the European 38.9MHz made quite a difference to N+/- problems. What surprises me is how well some sets could tolerate having direct inputs of 48+ channels (without them going through the converter UHF bypass filtering). Certainly, in the olden days, when faced with more than half a dozen channels, some sets tended to sag a bit at the knees.

But, as you have said, there used to be so many embargoed channels on a cable TV system - no adjacent, no N+/-5, no N+/-9, no sums or differences (with single-ended amplifiers) etc. It's a wonder anyone was able to get more than two or three channels!

If this is what they did, they could have used either of those channels from Crystal Palace. Next time I see him, I'll ask the man who will almost certainly know (if I remember!).

I had little to do with the system in London (I think I only went there once - underground, near Shepherds Bush IIRC). As I said, my involvement was among the concrete cows and the roundabouts.

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Ian

Given the lack of effectiveness of bomb sighting and delivery in those days, you needed a lot of big bombers to do any strategic damage at all.

I thought we were talking about Germany bombing the US.

I now of no evidence that care taken during construction the shielding of the bomb while being delivered was making the bombs that big and heavy. I'm under the impression that most of the gains that were made in minaturizing atomic bombs had to do with the design of the mechanism.

After all how much size or weight in shielding do you have on an A-Bomb that you can fire with a mortar or a bazooka?

"Other potential delivery methods include artillery shells, mines such as the Medium Atomic Demolition Munition and the (very odd) Blue Peacock, and nuclear depth charges, and nuclear torpedoes. An atomic mortar was also tested. Even an 'Atomic Bazooka' was designed to be used against large formations of tanks."

More may be known about comparable Russian weapons because of the break down of the Soviet military:

"These devices, "identified as RA-115s (or RA-115-01s for submersible weapons)" weigh from fifty to sixty pounds."

While the active materials in an A-bomb are radioactive, they aren't all that radioactive until they become a critical mass.

If you are obtaining current movies for just the cost of broadband, then you are not paying the usual fees for viewing copyrighted materials. The morality of that is up to you, but its not a fair comparison.

In the US the usual fee for obtaining a fairly current movie over broadband is about $5 each. Netflix over broadband is more like $9 per month, but the catalog is severely limited, both in terms of movies and also TV shows.

Redbox is the price/performance winner around here, and their nearest machine is within easy driving or biking distance.

We have TVs that will show encrypted content. They have a slot for a "Cablecard" which is a decrypter that is supplied by the content provider (cable company). AFAIK cable company DVRs have two Cablecards inside the box, and they are available for installation in PCs.

Apologies - I misread what you wrote!

I thought you wrote "the four set-top bypass channels had to be close to the LOCAL off-air broadcast channels ..."

As I said, I didn't actually visit the headend. All of our equipment was in a room in the basement of a large block not far from Marble Arch IIRC. Obviously, the headend couldn't have been far away ...

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Terry

In message , Terry Casey writes: []

And there was a film - 1970s I think - very loosely based on it. If I saw it now, I'd probably cringe at all sorts of errors in it, but I remember enjoying it _as a film_, then. I think it might have been "Operation Crossbow" - CBA to check.

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J. P. Gilliver. UMRA: 1960/

1965, I think you'll find. The rocket in the film was supposed to be a successor to the V2 and I'm sure that it is referred to as the V3 in the film although, as I later found out, the V3 was a multi-barrelled high velocity cannon, the site of which I've since visited.

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Terry

What morality? Sony owns the copyrights for the movies that they run on 'Crackle'. I never said I was watching 'current movies'. On the extremly rare chance that something cmes out I'll eiter watch it at a theater, or buy the disk. Thre have been two 'current movies' in the last 12 years that I wanted to see.

Not everyone is addicted to the latest Hollywood drivel. I 'watch' about 10-15 hours a week and a lot of that is local news. When I do watch more, it's when I'm too ill to do aything else.

Good for you. The nearest Redbox is about three miles, but I've never seen a title I wanted to watch.

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You can't have a sense of humor, if you have no sense.

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Or an attempt to raise the moral of the citizens after VE day? :)

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You can't have a sense of humor, if you have no sense.

In message , Michael A. Terrell writes

The word, of course, should have been 'morale'. I'm sure that, even during the war, British morals remained impeccable!

TV broadcasting didn't resume until 1946 - a year after VE Day.

After the war, it took a long time for life in Britain to get back normal. We were constantly being reminded of austerity and deprivation. For example, lots of things were rationed, and de-rationing didn't begin until 1948. I believe that certain things which has escaped rationing during the war were actually rationed after it ended. I remember sweets coming 'off the ration' in 1953. Meat was the last, in 1954. In 1951, we had the Festival of Britain, which was intended to boost both morale and the economy, and a lavish coronation in 1953.

I expect that the resumption of the TV service with a Mickey Mouse cartoon also helped to cheer us up - even though, at the time, it would only be seen by a handful of people in the London area. It could be that the urban legend which followed was actually more effective than the broadcast itself.

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Ian

Actually, and not surprisingly, you will find that morals in the UKofGB&NI deteroriated badly during the war.

In Ipswich in 1943, an increasing number of complaints were received about air raid shelters being used for ?immoral purposes".

I don't suppose they were any good for much else. And since when was sex immoral?

d

Indeed, I was going to ask J G Miller what he meant by "morals". Its certainly the case that both World Wars created significant social change including liberating women from many of the social restrictions that they had previously suffered from. If J G Miller thinks that giving women more independence equates to "morals deteriorating badly" then maybe he has a point!

David. .