Brazil certainly decided to play "odd man out" with PAL M. I can't see any real reason why they shouldn't have used NTSC. They were the only 525/60 country that didn't use NTSC.

PAL N is another matter. Argentina had the unfortunate combination of 625/50 monochrome TV with US channel spacing. So they couldn't use standard NTSC or standard PAL. Something had to give and the result was that ugly kludge of PAL N.

The arguments for PAL vs NTSC have been gone over many times. When Europe was looking at colour systems they could have adopted NTSC, suitably adapted to 625/50. The BBC and others experimented with 625 line NTSC (and 405 line NTSC) in the 1950s. Rightly or wrongly, at the time, the colour phase accuracy problems in NTSC were seen as severe. Hence both PAL and SECAM. In the later days of NTSC improved technology meant that NTSC could overcome the phase and differential phase problems.

Later still it was found that PAL was harder than NTSC to accurately convert to colour components for the digital world. Again advances in technology have made this unimportant.

I think the main disadvantages of adopting PAL in South America were economical, that it made it less likely that a color TV manufacturing plant could be established there without government support either directly to the manufacturer or by high tariffs on imports. Plus, the production and stocking of special models for those countries may have raised retail prices.

Technically, once equipment became transistorized and stable, the only advantage of PAL transmission I can think of was the reduction of wrong hues in ghost images.

There may have been an improvement in color accuracy (as there was in Europe) if the cameras were matrixed to the EBU phosphor standards and receivers used unmodified R-Y and B-Y axes. In the US, color matrixing was a sort of wild west situation in which CRTs did not use NTSC phosphors, but cameras (at least the early ones) were designed for them, while different TV makers did various non-ideal modifications to the chroma decoders to compensate approximately.

As a side note, I met someone from Argentina who said that many there learned to understand Portuguese because Brazil had the best soap operas.

A late friend of mine who'd lived & worked in the TV/radio trade in Argentina sang the praises of system PAL N. He said if you put an average British PAL I & an Average Argentine PAL N set side by side you wouldn't be able tell the difference between them. He said Britain chose the wrong 625 system & should have gone for system N.

Must admit I was impressed with the NTSC M pictures I saw when I was in USA & Bahamas..

Some SA countries appeared to have been spooked by Euro trade delegations - they paid a hell of a price. Not as easy to bamboozle: Korea, Taiwan..

The concept of colour phase alternation, the basis of PAL, was considered by (I think) Hazeltine labs in the very early 1950s. While NTSC was being developed. Until there was a practical 1 line delay available at low cost the advantages of CPA were minimal. Both SECAM and PAL depended on having a 1 line delay in the receiver. Less critical for SECAM than PAL. Simple PAL receivers (without a delay line) were feasible but were hardly, if at all, marketed. The results were not good.

As for PAL N, I worked for MIchael Cox Electronics in the early 1980s when Argentina went to PAL N. We designed and supplied PAL B to PAL N transcoders as all production was done with standard PAL B kit. ISTR the pictures, as viewed side by side in the lab, weren't bad. On critical material you could tell the difference. Of course VHS and Betamax recorders reduced picture quality to below PAL N.

Do you think Argentina, Brazil, being what they are, might have been open to a discreet bribe or two... thus leading to those bastardized systems?

How did the UK deal with US videotapes 1967 - 1980? Did they get 16mm kinephoto copies? How good were analogue NTSC -> PAL tape conversions (using glass delay-lines to repeat/insert extra lines?) Did Cox make a box for this?

I remember watching the Andy Williams show on BBC1 (405 lines black & white) in the mid/late 1960's & the picture quality was dire = it looked blurred & any movement was jerky. Into the 70's the conversion quality improved but there was still the jerkiness & when in colour the colours were often wrong. The first live moon landing was converted twice = from 240 lines 10 frames per second to 525/60 FPS then to 405/50 FPS. The later landings looked very clear in comparison

Cox never made field rate converters.

The world's first electronic (as against optical) 525/60 <> 625/50 converter was the BBC's analogue machine using glass delays. From 1968. I believe it worked well but was a beast to keep working nicely. The IBA "DICE" was the first digital converter and worked very well. 1971 I think. Followed by the BBC's ACE with 4 field, 4 line interpolation. This set a pretty high bar for quality until motion compensation was feasible.

Most 2" quadruplex machines were multistandard so could reply NTSC tapes in Europe. A lot of US programmes back then were produced on film which was just run 4% fast in 50Hz countries. A rather happier solution than 3:2 pulldown.

Argentina were stuck between a rock and a hard place. US channel spacing and 625/50 meant wahever they used would be unique unless they opted for a wholesale change to 525/60 and NTSC. In retrospect this might have been feasible as just about any 625/50 monochrome set will display 525/60 with minimal adjustment.

We had a 19" GE set with VIR that we got shortly after it was introduced. Ours was a 1977 model. It never worked right. Saturation and hue would just randomly jump all over the place. I have never seen faces such a brilliant shade of bright blue as on that set. It seemed to vary from one station to another, and I was convinced that our local ABC affiliate wasn't actually transmitting the signal but had some kind of noise present that tricked the TV into switching into VIR mode. Anyway we turned it off after a while.

About the same time the shop I worked in was selling Quasar TVs and in around 1979 or 1980 they came out with Super Dynacolor that also had VIR. I believe those and the GEs were the first on the market.

The second set of controls for VIR only meant that there were two ways for the consumer to monkey with the color setting and make everything terrible with or without VIR. The awful truth of VIR to the consumer is that only GE sets seemed to support it, and GE had a reputation for lousy quality and iffy reliability.

There were three GE color 19" sets in the extended family (one a JCPenney rebadge) and each one had a CRT that went bad quickly with weak green and smeared reds. The one my mother had came with a hair-trigger color-killer that no number of shop trips could correct. I think they gave up after the 8th repair visit. The tube went south and lost correct color along with focus within 5 years from new even with minimal hours (due to that color-killer annoyance).

A friend owns the only GE VIR set I've seen in person. That set has a gassy CRT.... it arcs between CRT elements then goes into shutdown.

"Less critical for SECAM than PAL" caught my attention here.

I had always thought that the delay line was strongly encouraged in PAL for the color correction benefit, with some manufacturers leaving it out to save a few Marks (resulting in "Hanover bars", and called "Simple PAL") and others using a delay line to store alternate R-Y lines and escape patent royalties payment, wheras in SECAM a delay line would be absolutely essential as SECAM only transmitted one axis of chromience with each line.

9OooIWell, there are other reasons to consider before one comes to the conclusion that a few billion Cruzandos changed under the table.

Brazil used and still uses 60Hz utility power, so they logically used the 525-line, 60-field USA system. Like all of the Americas*, channels had/have 6MHz total bandwidth each, hence SECAM or PAL B, D, G or K were off the table. Brazil went color far later than the USA did. Whether their decision was done to reject American dominance or simply to throw away that pesky hue knob may never be known.

Argentina and Uruguay were another matter. The had/have 50Hz power. They used System N, with 625 lines at 50 fields (25 frames) per second. Like Brazil, they only started using color when the PAL system was well established, and no country ever made a standard of NTSC and 50 fields, so PAL must have seemed a logical choice.

*Excluding some Caribbean Islands that used 50-field systems from their parent countries, all either low power or cable only.
Mexico experimented with System N monochrome. A TV DXer showed me a photo of an ID slide from XEFB-TV (then channel 3), Monterrey NL. Below the call sign, it said: "Nuestra siguiente programa se ve mejor en un Phillips". This DXer told me he lost vertical hold the instant the slide was replaced by the program.

System M and system N had very closely matched matched line rates (15750 versus 15625), thus horizontal sync was no problem. It is also true that one system's vertical rate may be compensated to the other with adjustment of the vertical hold, size and linearity controls. However, having the field rate match the power supply frequency is still desirable.
I own an ATSC converter box that offers PAL B/G video output (along with 480i, 480p, 720p and 1080i).
When I fed its PAL output to my 1958 Emerson TV, the picture was sharper but with more flicker, as I expected. However, the picture wobbled in a cycle- the picture looked like an image atop a shaking bowl of jelly. My suspicion is that a 60Hz magnetic field from within my home (possibly the autotransformer power supply of the television itself) was interacting with the 50Hz field of the vertical yoke.

There is probably some elderly engineer there or some obscure tech publication where that info exists.

My understanding: In PAL, the length of the delay determines if the chroma is exactly phased right from line to line. In an NTSC comb filter, the exact length of the delay determines if the chroma and luma sidebands are precisely separated. In SECAM, the delay is only providing low-resolution FM chroma, so doesn't need to be so precise.

What was the Japanese experience with their mix of 50Hz and 60Hz power?

In PAL the delay line length is very critical, to within a few degrees of subcarrier. A good NTSC comb filter is likewise critical to get good subcarrier cancellation. A SECAM delay line is relatively uncritical.

Many import Japanese tube era TVs I've seen seem to have on average more and bigger lytic caps than American sets so I'd imagine they had issues and dealt with it by liberal use of capacitive filtering.

A-ha! I see why I was confused.

In PAL, the quality (more specifically, the precision) of the delay line is critical, but the delay line can be left out if one were tolerant of "Hanover bars".

In SECAM, the mere presence of the delay line is critical (no delay line, no SECAM).

Discovered Good article on VIR in RADIO-TELEVISION. It states VIR was designed for pro application, and only later was it extended to consumers (much the same way as DTMF routing was used behind the scenes by telcos, and only later extended to consumers.)

The article describes the use of the Tektronix 1440, a very precision instrument with no tweaking controls on front panel (unlike the consumer VIR) and how the 1440 (in a closed loop) would correct a transmitter for instance.

By providing subjective fine tuning on the home TV version, they were either admitting that they had lost the control VIR promised, or that the built-to-a-price GE circuit board lacked the precision of the pro 1440.

Wooo digging up an old thread!

Anyway - I've always wondered - how does the PAL decoder know which way the phase is, to decode properly?

"Oscillating burst"

A (R-Y) or -(R-Y) component is added to the burst on alternate lines, making its phase plus or minus 45 degrees from the NTSC burst.

As mentioned somewhere here, there was a patent on detecting this in the receiver, but one maker avoided the patent by not using the detector. Instead, they added a button so the user could flip the phase sequence from plus/minus to minus/plus in case it came up wrong at random.

VIR= Vertical Interval Reference. Remember, TV stations using video had to stay synchronized to the network color burst reference for timing and interchange purposes. Also remember there was Time Code involved for locally produced video content using video tape sources. Known as SMPTE (Society Of Motion Picture and Television Engineers) Time Code. Hope this explains the underlying issues with VIR's use and implementation and allow set owners freedom of their vision and taste in color settings at home.

The thread that refuses to die!

Kent's comment just made something click for me: on our GE VIR set, everything always went whacky when the local ABC affiliate switched from network content to local, either programming or commercial breaks: tint so far off you couldn't manually adjust it so bad. It was common to see bright blue faces for a few seconds when they switched. It must have been a sync error at the station.