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Meet My New PAL!

 
Anonymous
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A PAL (625/50 CCIR system I) Video Measurement Set.

Been on my test equipment bucket list for some time, and now fulfilled!

I have working and calibrated Tek 1480R NTSC and calibrated Tek 1481R PAL gear, plus both a Tek TSG130 NTSC and Tek TSG131 PAL video signal generators.

As expected the front panel graticle lamps are defective; hopefully some careful lamp swapping will sort that.

Here are PIX of "as found condition", after a front panel calibration:

DSCN8165_cropped_clr_resize.JPG

It's been quite a few years since I spent any time looking closely at PAL colour bar signals:

DSCN8158_clr_resize.JPGDSCN8161_clr_resize.JPG

Of course, the cluttered PAL vector display can be 'cleaned up' to show only +V vectors, a bit like an NTSC display:

DSCN8160_clr_resize.JPG

This was a good find for me, as PAL test equipment is generally for the smaller 'export market', and quite rare here in NTSC land.

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Posted : 20/06/2017 6:19 am
Nuvistor
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Are you planning a new building to house your TV station, may need one before much longer. A tower in the back yard with a UHF slot antenna on the top to finish it all off.innocent

As for the termites, hungry little blighters, the Township where my daughter lived had one house with termites, the whole township was treated as a precaution. 

Note, I find the word " Township" a little grand, to me it was a housing estate managed and funded by the residents.

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Posted : 20/06/2017 9:50 am
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nuvistor said
Are you planning a new building to house your TV station, may need one before much longer. A tower in the back yard with a UHF slot antenna on the top to finish it all off.

No worries, having been down this path before and as an older and hopefully wiser person I'll exercise restraint...

As for the termites, hungry little blighters, the Township where my daughter lived had one house with termites, the whole township was treated as a precaution.

Google for 'Termite Damage' PIX. Its taken quite seriously here! Most single family homes are wood. Usually the fumigation, that requires tenting of the entire building, is done when property changes hand and is empty. At other times, such as ours, there's quite a bit more effort to remove the occupants (two or three nights in a hotel), pets, house plants, and all food. Also, the utilities are turned off, and the door keys confiscated. The crews do this often and have it down to an efficient and fine art. 

Note, I find the word " Township" a little grand, to me it was a housing estate managed and funded by the residents.  

More often seen on the East coast which was settled by Europeans. Here on the West coast we use (miss-use?) 'Village' or 'City' instead. There are also private roads and communities as you noted, that may not have the traditional forms of government. An example is the 'HOA' or Home Owners Association that may apply to group of homes, apartments (flats) or the like. They collect monthly 'Association Fees', manage a budget, and contract for community services (landscaping, snow-removal, painting, security, trash pick up, inspections and termite treatments, etc.) Residents are encouraged to volunteer to serve on the HOA board. I've done that a couple of times.

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Posted : 20/06/2017 9:20 pm
PYE625
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Great to see your new PAL, very good.... Just hope he is  Never Two Similar Colours when he shouldn't be. grin_gif

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Posted : 21/06/2017 7:55 pm
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PYE625 said
Great to see your new PAL, very good.... Just hope he is  Never Two Similar Colours when he shouldn't be. grin_gif  

Good point! Now what if I shift my curiosity to a "System Complementary (to) AMerica's", instead of sticking with "Peace At Last", or was that "Pay Another License (fee)"?

A couple of 1980s vintage Sony TVs in my collection have built-in NTSC, NTSC443, PAL, and SECAM decoders; but I only have generators for two of those formats. These video monitors also have analog component formats (YPbPr, RGB) and selectable 16:9 display format. Oh, and one has SDI (Serial Digital Interface), but I don't have a source to try it out either.

There's been quite a basket-full of analogue and digital video signal formats in the recent decades. The evolution of modern all-digital interconnects benefits all of us here; older and very capable equipment, that was once very costly, is on its way to the e-waste stream (better know as the skip, dump, or landfill) I think this is the golden age of hobby analogue video hardware!

NTSC (Never Twice, Same Color) got a bad rap from the technology of the post WW-II era (valves/tubes, and Image Orthicon camera tubes, plus relentless pressure to reduce the cost of home receivers, which seldom got routine tune ups) The fundamental analogue TV science was sound, and later the UK/EU benefited from stable and cool running solid-state electronics and Lead-Oxide camera tubes.

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Posted : 21/06/2017 8:36 pm
Terry
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I agree with Never Twice (the) Same Colour but the the SECAM version I know is a much better fit and entirely true: 

System Essentially Contrary (to the) American Method.

Peace At Last for PAL worked well and looked to be the system that would be adopted throughout Europe - except for France, of course! - until Général de Gaulle played the political card and persuaded the Soviets that they wouldn't want to use an American system or its German variant!

From a technical point of view, the Russians were already sold on NTSC. They had been very worried about differential phase distortion on their very long links until the BBC visited Moscow to demonstrate their equalisation methods. NTSC signals were sent to (I think) Kiev and back and the before and after pictures were displayed on two sets. The Russian engineers were hard pressed to see any difference and PAL, of course, would have been even better.

The BBC's technical standards were, I think, usually regarded as being the best in the world, which is more than be said for the US, considering some of the early NTSC programmes screened here - in PAL, of course.

It can be argued that a lot of the early problems were caused by rushing to get sets to market in a mad rush once NTSC had finally been approved but, after 12 or 13 years, the programmes we saw here still seemed to be of substandard quality.

I remember installing a Dynatron Colour set in a customers house while Bobby Kennedy's funeral was taking place. Fortunately the customer just left us to it because we found ourselves looking at a long shot down a long straight road as the motorcade slowly proceeded down it. Unfortunately there was severe convergence error in the camera which resulted on the row of right hand tail lamps appearing on the left of the cars whist the other row of lights slowly proceeded along the edge of the adjacent field!

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Posted : 26/06/2017 3:10 pm
Nuvistor
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The NTSC  pictures that for me stood out as being excellent, even after conversion to PAL, were the 1968 Mexico Olympics, this I presume would have been via a satellite link.

I agree a lot of the USA productions that were video tape were poor, not sure if it was poor recording, playback or a bit of both. Colour banding on the picture could be quite noticeable which I put down to the quad heads not being aligned, that's a guess, I have no experience with quad tape units. 

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Posted : 26/06/2017 3:54 pm
Terry
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I would guess that, for something as prestigious as the Olympics, every broadcaster in the world would want first class pictures and would only allow equipment in full working order to be employed with no short cuts! Also, wouldn't the Mexican broadcasters be in charge of this?

I remember one our college instructors telling us that all the camera tubes used by broadcasters in this country were leased and they would whistle up the manufacturer at the first signs of degraded performance. In the US, on the other hand, the broadcasters bought the tubes outright so as long as the camera produced some semblance of a picture, the tube stayed in service!

I remember that, when the great 405/625-line discussion was going on and before the Pilkington Committee produced its findings, a representative of one of the US networks (can't remember which one) who was attending a conference in the UK was reported as saying that we should go down the 625-line route - but then added that he thought our 405-line pictures were better than  their 525-line ones!

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Posted : 26/06/2017 6:53 pm
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Terry said
I agree with Never Twice (the) Same Colour but the the SECAM version I know is a much better fit and entirely true: 

System Essentially Contrary (to the) American Method.

Oh, yes. Much better than the SECAM moniker I had heard.

BTW, much of the French SECAM content was created in PAL and transcoded to SECAM before the transmitter.

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Posted : 26/06/2017 7:22 pm
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Terry said
I would guess that, for something as prestigious as the Olympics, every broadcaster in the world would want first class pictures and would only allow equipment in full working order to be employed with no short cuts! Also, wouldn't the Mexican broadcasters be in charge of this?

The Olympics every four years drove the US Broadcasters to buy and use the latest kit. After the Olympics much of it was "handed down" to the Network O&O (Owned and Operated) stations in major markets, who in turn "handed down" their used equipment to the independent or affiliated stations in smaller markets, that didn't have the budget for any new kit.

Olympic events typically build a Broadcasting Center that collects and shares pool video between the various outlets.

I heard (sorry don't have a cite) that some non-European events were produced in PAL for export, and standards converted to NTSC for the US. The source material was therefore in PAL and better than had it been produced in NTSC.

Today its all digital, and multiple generations are almost perfect compared to analogue generations.

I remember one our college instructors telling us that all the camera tubes used by broadcasters in this country were leased and they would whistle up the manufacturer at the first signs of degraded performance. In the US, on the other hand, the broadcasters bought the tubes outright so as long as the camera produced some semblance of a picture, the tube stayed in service!

In the UK the BBC did lease camera tubes from EMI (Emitron, Super Emitron) and were guaranteed two hundred hours operation. Tubes were logged out of EMI's on site 'cage' stock room and logged back after production. EMI seldom hit the 200 hour mark, and lost money on tube replacements.

A legacy of the leased tube arrangement can be found on EMI 2001 cameras (1967 - 1980ish) There's a running-hours meter and heater on/off switches (to turn off the tubes when idle) on the camera head. By the time of conversion to colour in the UK camera tubes were no longer on lease, as far as I know, and the meters served little practical use.

emi2001_hour_meter.jpg

The heater switch might accidentally be turned off, and the camera died... later a guard was put over the heater switch. However, secretly turning off the heaters while the camera person wasn't looking was a great practical joke on the studio floor. 

emi2001_htr_sw.jpg

There was strong competition amongst camera tube manufacturers, at the peak of camera tube use there were perhaps 1,100 TV stations in the USA, each with three (or more) studio cameras and each camera with three camera tubes. A healthy business.

Camera tube sets of three sold for approximately 2700USD. In small markets there was financial pressure to keep the cameras running until a drastic tube failure. In smaller markets single tubes were replaced ad hoc, I think the network studios were better disciplined and changed all tubes at regular intervals.

Used tubes were always stored in case a new tube failed early on, and over time we had boxes of "not new" camera tubes stored away. Many with hand-written comments such as "Blue channel from camera 3" or "shading on left" or "some pin holes near bottom right" I still have some...!

Often the smaller market stations used cheaper vidicon tubes in the telelcine chain, which served for stills during local news and station announcements, as well as film scanning for "the movie of the week". The locally sourced late night movie images were terrible! 

I remember that, when the great 405/625-line discussion was going on and before the Pilkington Committee produced its findings, a representative of one of the US networks (can't remember which one) who was attending a conference in the UK was reported as saying that we should go down the 625-line route - but then added that he thought our 405-line pictures were better than  their 525-line ones! 

Apart from colour test transmissions the UK 405/50 system was only black and white, while the US 525/60 system had been colour since the 1950s. The three USA networks (ABC, CBS, NBC) originates programming in New York City, plus the public (formerly non-commercial taxpayer funded educational) PBS channel originates in Washington DC. All on the East coast. Before satellite distribution the signals were carried by long-haul transmission (about 5,000km) leased from the Bell telephone company. A combination of point-to-point microwave links and buried coaxial cables!

The West coast feeds, for the three timezone delay, were usually recorded to tape and re-transmitted on the West coast. There was obviously degradation in signal quality and at least one more VT generation.

Even today network programs are promoted by time slots such as "Eight PM East and West, Seven PM Central" to account for the local time zones. This also explains why there is a strong bias for New York news coverage compared to the rest of the country.   

Most people 'watch TV' but how many know a bit about what it takes to create and deliver TV?

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Posted : 26/06/2017 8:25 pm
Nuvistor
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Attached info on the USA coast to coast microwave, taken from Radio and Electronics Jan 1952. The first microwave link in the UK was Holme Moss to Pontop Pike in 1953 in time for the Coronation.

IMG_1263.JPG

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Posted : 26/06/2017 8:57 pm
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nuvistor said
Attached info on the USA coast to coast microwave, taken from Radio and Electronics Jan 1952. The first microwave link in the UK was Holme Moss to Pontop Pike in 1953 in time for the Coronation.

Nice find, nuvistor! At the time this would have been leading-edge technology. Microwave paths had an advantage over coaxial cables.

When I lived in Chicago a good friend had worked during the 1960s and '70s for Western Electric (WECO) installing and maintaining microwave links for telephone trunk lines. The technology was interesting; including compensation for microwave signal deflection between daylight and nighttime hours.

The BT Tower (formerly GPO Tower or Post Office Tower) in London was built as the hub for line-of-sight microwave links, requiring an act of Parliament to allow it's tower height, at the time the tallest structure in London.

Many US TV stations locate their transmitters on local high ground, and therefore beam signals over microwave using an STL (Studio Transmitter Link)

There was (perhaps still is) a major microwave facility in Terre Haute, Indiana, an important location as the TV feed from New York is split to serve Chicago to the north, and also feed the same signal west towards the Rockies. Today coast-to-coast and continent-to-continent links use satellites.

There have been a few instances of pirates taking over the microwave feeds (and also misuse of satellite teleport facilities) to send propaganda or 'joke' messages that override legitimate TV traffic.

Captain Midnight satellite intrusion from Florida, USA

Southern Television in UK

Max Headroom at WTTW and WGN in Chicago, USA

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Posted : 26/06/2017 10:04 pm