This test card used to broadcast on the albanian television during communist times until 2012
@t0nito10 күн бұрын
This applies to all BE-4 chassis TVs, I did this mod 2 years ago on my KV-M1450E, I got the MC44002 from AliExpress at the time
@KayTestcard14 күн бұрын
Do you really have the PM5644 SECAM version? Do you have the PM5644L/00 because I'm ready and want to use it too?
@Sebanek73816 күн бұрын
i have windows pc but not linux machine
@t0nito16 күн бұрын
I've made some progress since I posted the last comment. It works so much better under Linux Mint instead of Windows. I use a HackRF clone that doesn't have that banding issue, fortunately. Meanwhile I've been playing around with the code of both HackTV and HackTV GUI and I've made some changes, I've enabled NICAM on SECAM-BG mode and added PAL60-BG, PAL60-DK, NTSC-BG, NTSC-DK, NTSC 4.43-I, NTSC 4.43-BG and NTSC-4.43-DK modes.
@t0nito23 күн бұрын
I just tried this also through virtualization, SECAM is impossible for me, UUUUUUUUUUUUUUUUUUUUU starts appearing all over the place and the image is very glitchy, I tried reducing sample rate but no difference PAL test card seem stable but playing a video it also glitches from time to time, any idea on how to avoid this?
@t0nito24 күн бұрын
I wonder if setting the sample rate to 15.625 would make the bars dissapear completely, I have a HackRF I definately have to give this a try, is there a Windows version?
@faming114428 күн бұрын
I find your reasoning at 2'00" - 2'34" a bit obscure. What you are trying to say is that at the time 16:9 content was to be delivered using full existing signal resolution (as opposed to letterboxing) for 16:9 TV-sets, anamorphic was not an option as current 4:3 TV's had no letterbox feature . Hence PALplus was created which is backwards compatible with all 4:3 TV's (showing letterbox format) and still use the full signal for 16:9 TV's. On a side note: letterbox format on 4:3 TV's had already be in use for widescreen movies, before pan & scan became the fashion. After the arrival of 16:9 TV-sets and before, besides and within PALplus letterbox came back. 16:9 TV's lacking PALplus or getting a plain letterbox signal simply upscaled the picture pushing the black bars of of the screen.
@digitalmediafanАй бұрын
When did TVNZ start using nicam ?
@stevejones4061Ай бұрын
For those who remember Grandstand on a Saturday on the BBC, most of the sound from the OB truck was carried over SiS in some form, either via direct video link, microwave or Sat. The sound supervisors all had various ways of pre eq-ing the audio going in the SiS encoder to cope with the detrimental effects of the anti-alias filter and the 10 bit compander. There were complaints that the starter's gun in athletics sounded a bit lacking in 'bang' otherwise. Major OBs would have standard analogue 15kHz music lines provided by the Post Office (BT) with video+SiS as a backup, though for convenience at TVC, quite often the analogue audio circuit would be forgotten about, as the SiS sound was easier the manage with the audio being embedded in the same video. Often at major dual media (Radio & TV coverage) events such as horse racing or rugby internationals it was common for the radio broadcasters use a video circuit with SiS as there was more spare capacity in the video provision. Of course, any BBC piece of audio equipment of that era would have B-gauge (PO316) sockets for audio connections to supplement the XLRs. The entire sound desk patch bay (jackfield) and ancillary racks in the OB truck were PO316. When 'Bantam' mini plugs were introduced in the early 1980s to save space, the reliability of the audio connections went down significantly. Would you need a filter on the DAC output if you are feeding the signal into a line output transformer? I'm guessing a coupling capacitor and the inductance of the transformer would do the job. Transformers are probably manufactured by Sowter BTW.
@YuthasinKhamya747Ай бұрын
I will to buy PM5644 also. But model number is PM5644G/00 in 2000 USD
@stephenneal7373Ай бұрын
Sorry - bit of a comment stream. Interesting that it's a BBC BASIC running on a Z80, as the BBC Micro was 6502-based (not Z80). However there was a Z80 BBC Basic used for the BBC Micro Z80 Second Processor (and it was also sold for other Z80 platforms). Richard Russell, who worked for the BBC in Designs Dept, developed a lot of in-house equipment, and was heavily involved with the BBC Micro, and keeps BBC BASIC alive across a number of architectures, may be able to advise.
@mattstvbarnАй бұрын
I should have made it clearer when I was mumbling on. The Z80 observation and "BBC Micro" description wasn't intended to refer to the consumer BBC Micro, but rather the ADZE BBC Microcomputer designed by John Robinson, used in various broadcast kit. There is a picture of it on my website: techmattmillman.s3.dualstack.us-east-1.amazonaws.com/wp-content/uploads/2022/08/combiner_pcb.jpg it is the design ancestor of the item I showed in this video. JohnR actually did the handover to TVT for this module.
@stevejones4061Ай бұрын
@@mattstvbarn to help get BBC engineers familiar with the use of microcontrollers in broadcast equipment in the 1980s, part of their training included how to use a small Z80 prototype board, with the usual RS232/422 hardware ports, to make bespoke modules for housekeeping duties such as the monitoring and control of larger items. Programming was usually done in Z80 assembly and figForth.
@stephenneal7373Ай бұрын
One other thing I've been told in the past - which may or may not be true - is that the RE DSIS system was easier to remodulate to NICAM and needed less re-framing. It could be that the TVT SiS fixed data burst vs the RE slightly variable data burst is related to this ? (It could be that RE's system requires less buffering?)
@stephenneal7373Ай бұрын
B-gauge jacks were standard in BBC analogue audio jackfields and on BBC sound gear - so not surprising they were used on the BBC TVT stuff.
@stephenneal7373Ай бұрын
Those reframer interruptions were heard on NICAM whenever a BBC regional centre switched itself into and out of circuit before a regional opt-out (called soft-opting). AIUI the opt-out switch switched between incoming Network with Dual Channel SiS and local studio with its own Dual Channel SiS. Before the actual switch to the regional output, the local studio would have network vision (and decoded dual channel SIS audio) on its sound and vision mixers, and the output of that studio would be Dual Channel SIS encoded. The opt-out switch - that switched the local studio into the transmission path would switch from incoming network with SiS to local studio with SiS (with the local studio carrying the same incoming sound and vision as network). Then when the opt-out was called the local studio would cut away from network sound and vision to local sources for the duration of the regional opt, at the end you'd cut back to network sound and vision, and then the opt-out switch would be moved to take network (with network SiS) clean - and you'd get another reformer interruption.
@mattstvbarnАй бұрын
Interesting. This sounds exactly the same as the situation they had at TV2/DK. Haven't yet heard of any other non-UK examples however. Normally NICAM is just tacked on at the end of the tx chain negating the need for reframers.
@stephenneal7373Ай бұрын
@@mattstvbarn Yep - my guess is that it was more used in areas that used PAL composite distribution (the BBC used 140Mbs digital composite circuits to regional centres and then a mix of digital composite fibre and analogue microwave for transmitter distribution) rather than compressed digital component (where you had no real syncs to put sound in?)
@ZXGuesserАй бұрын
I assume the low bitrate speech you mention is the 9.5kbps CELP codec developed for the AUDETEL project. I don't know whether the NICAM additional data version was ever actually used anywhere - the UK audio description trial broadcasts used the even lower bitrate (7.5kbps) teletext transmission version. I would be *very* interested if any of your viewers ever turn up one of those coders, but I fear they're another thing that only existed in single digit numbers of units and have long since been scrapped.
@mattstvbarnАй бұрын
That would be a very interesting thing to find. Knowing what to look for is always a good place to start!
@ZXGuesserАй бұрын
It was developed by the University of Surrey as "Speka Ltd". It seems like the BBC had at least two encoders as they generated audio streams live (frequently we find programme audio from TV or radio channels being routed out). ITV's signals were pre-prepared for playout like subtitles. One of the decoders still exists in Peter Weitzel's collection. Decoding was mostly reverse engineered before we learnt that.
@stephenneal7373Ай бұрын
One thing to remember when discussing SIS is that it wasn't limited to use for transmission distribution - BBC Outside Broadcasts (and the EBU) used SIS extensively for outside broadcasts over microwave and satellite circuits - where NICAM 728 compatibility was a non-issue (you would have been going analogue in at the OB end and analogue out at the network centre end - not baseband NICAM or PCM digital) - and having stereo SIS gear to link OBs back to base in stereo was a major requirement (Sony PCM F1s were sometimes used on a second circuit in the very early days I believe, as well as for Radio OBs) The NICAM 3 / 676 stuff may well have been an attempt to solve that problem (ignoring transmission distribution to NICAM 728 TV transmitters) - as you only needed the decoder and encoder at either end to be compatible.
@stephenneal7373Ай бұрын
I believe both C4 and TV-am made use of the NICAM spare data capacity for a low-quality talkback channel to outside broadcasts. This makes sense as TV-am was routed directly to the transmitters during their broadcasting hours I believe - and so if the data had been in the SiS distribution it would have reached every transmitter (irrespective of whether the local company had any support for NICAM data talkback?). I have heard reference to it being used for C4 racing - presumably after 1992 when C4 took over advertising playout from the local ITV companies and added their own distribution to transmitters. However I believe C4 moved to 34Mbs compressed distribution around this time too - so it may not have been fully end-to-end SiS? (Was it ETSI compression they used? It was a major reason for them choosing D5 over Digital Betacam as they were concerned about compression concatenation at the time I seem to remember?)
@gjones8454Ай бұрын
Its likely the bang was the electrolyte across two high voltage tracks and creating a short, as I've experience this in the past and finding no damaged components.
@charlesdorval394Ай бұрын
Very interesting! Also, HOLY F..K that PCB burn!!
@justinmijnbuisАй бұрын
The fact that people with past involvement and expertise pitch in is fantastic. Super interesting, thank Matt.
@sickdear.officialАй бұрын
Hi Matt, Hello, Today I have something to tell you. Last Monday I will start buying Philips PM5644G/00 Color Pattern Generator. I asked Mr. Kevin Munika, a Kenyan seller on WhatsApp that the price of PM5644 is 2000 USD, if I have the money I will start buying it right away. Thank you
@SO_DIGITALАй бұрын
I'd like to reference your S-i-S videos on my website where I discuss it's use with subscription television in the 80s and 90s.
@mattstvbarnАй бұрын
Go for it.
@SO_DIGITALАй бұрын
Oooh, now THIS is interesting. I've been fascinated by this for a long time.
@lordflashheart7427Ай бұрын
so what size cap did you use ?
@paranoidgenius91642 ай бұрын
You can achieve s-video output through the scart socket with a scart to RCA & composite video adapter with an s-video port built in, just use the s-video lead with the red & white audio leads leaving the yellow composite video lead unplugged, or use another screen with composite video output & you can see the comparisons between them in real time.
@kokoko3k2 ай бұрын
4:46: "this is a beat pattern which occours between the oscillator in the color decoder and input signal" Could you explain why that happens? Thanks!
@kiltrash12 ай бұрын
Information on the BBC Decoder is on the bbceng info site, under the equipment name CD3/504. Further information can then be found for each sub-module, eg AM1/38, UN16/515, FL1/31 etc. This may not exactly match the Varian unit that you have, but it should be close to the BBC Design.
@mattstvbarn2 ай бұрын
Thanks for that. Just had a quick look. This appears to be for the old mono system, which actually I have yet to come across such detailed information about! Very interesting...
@michaeldavison97612 ай бұрын
My first digital capable TV, a 28" 16:9 Hitachi had undocumented analogue capabilities which I discovered using my first analogue and digital satellite receiver. The satellite receiver could send 625/ PAL to the TV whatever satellite signal was being received but could be set to send in NTSC and SECAM as well and the Hitachi TV would accept them. When a NTSC 525line satellite signal was fed to the TV as 625/PAL motion was jerky which cleared when switched to 525/NTSC and a TINT option became available in the TV's settings menu. When the French analogue satellite 625/SECAM signals were seen, text had noticeable colour ringing which I think must be the origin of the STREAKAM nickname for the system.
@Robbie68K2 ай бұрын
Thanks for sharing. I have one of these myself that was used by Dutch television in Hilversum. It still works, I only had to replace the bulb in the power switch.
@FrancisLitanofficialJAPINOY2 ай бұрын
9:10 also Luxembourg nearby border of France, used SECAM-L and also PAL-B/G.
@fuertysuntanman2 ай бұрын
hi,enjoyed your video, .Back i early 1990's i hunted satellite feeds,one saturday night i came across Noel Edmonds show using SiS on their satellite OB, live at a birthday party somewhere in the uk, Noel was in studio dressed as leatherman from the village people, his feed was then fed via Sat and recieved at OB site, mixed with the YMCA video being shown at the birthday party,,Thus, when the man whos birthday it was, got up on stage to do the YMCA carriokee, the screen behind him, then showed Noel joining in......... this was the suprise, when revealed... all done in SIS, i did record all this show using SIS inserter decoder,, its on Vhs somewhere..... must look.for it..👍
@Matt_Quinn-Personal_Account2 ай бұрын
25:50 - This rings a very vague bell; is it possible that the low-quality audio feed was some sort of comms circuit? As a Cameraman I was never involved with TX/RX hardware; but I recall seeing feeds with tinny telephonic-sounding gallery audio on them which was (I recall being told) sent 'SIS'.
@AnthonyZwygart2 ай бұрын
Hi Matt. In 1990 I worked for a company in Melbourne Australia supporting re 140Mbps Video CODECs(8:00). I spent some time in Copenhagen training at re. They were great folks. You're right, their documentation was outstanding as was their engineering. I do remember learning about their SIS but never used it in Australia. They had broadcast quality audio coders (15kHz?) that would interleave data into slots in the 140Mbps stream and I believe there was room for 2Mbps data as well. The 10 bit video sample rate was locked to 3 times the colour subcarrier and there was some very clever padding and frame size manipulation to sync with the 140Mbps data stream. Varying the SIS data rate as you mentioned would be consistent. Pseudo random encryption was not primarily for security but rather to prevent dc offsets occuring as a result of repeating bit patterns during static video scenes. I'd love to get hold of a TxRx pair. Thanks for the video. Was a real nostalgia trip.
@mattstvbarn2 ай бұрын
Glad you enjoyed it. Would love to get a pair of those codecs on the channel. That particular coder is surviving but all of the decoders had been scrapped unfortunately.
@paulread29222 ай бұрын
I have a copy of the user manual as a PDF that you can have. You will be able to do more experiments and even get into the monitoring software that drives the error LEDs. I have a Harris badged coder and a TVT decoder saved from the skip. The open frame construction always made me nervous when working in racks with this gear in.
@mattstvbarn2 ай бұрын
Brilliant. I look forward to seeing it. I think the open frame construction made sense in terms of how it was deployed. Very good for airflow, just a bit fragile when used standalone. I believe there was an official ruggedised case for the equipment for cases where it had to be used standalone!
@mattstvbarn2 ай бұрын
Many thanks for that. No circuit diagrams in that manual I take it?
@mattstvbarn2 ай бұрын
Just wondered if you had seen the response I sent to your email on Tuesday? On my end I had noticed that your message ended up in my junk folder for some reason!
@Richardincancale2 ай бұрын
Very interesting fun! Shows again the robustness of Nicam! There’s an interesting BBC R&D report from 1966 comparing the relative goodness of using various pulse techniques to carry sound in sync (1966/58). They compare PCM (which obviously won) with PAM, PWM and PPM. There doesn’t seem to be any indication that any of these other SiS techniques were actually in use though. In the references there are references to a paper about the French 819 line system muxing sound. Has anyone ever seen this fabled HD system from the 1960s?
@kentsmith75072 ай бұрын
TVNZ enabled the NICAM 1988 I believe. It was very gradual and it was mostly just mono on the stereo NICAM channels. I think it was originally just Shortland Street, some commercials and a late night music show that we're actual stereo for quite a long time. TV3 launch in 1989 was first to go full time stereo and was amazingly exciting time for a tech geek. Probably easier for TV3 S starting with new infrastructure rather than having to retrofit. I purchased a Mitsibishi E70 VCR and recall paying about $500 just to get the optional NICAM decoder module installed before any NZ broadcasting. Was pleased when it started getting some use. :)
@mattstvbarn2 ай бұрын
It was my understanding that it didn't officially launch until 1989? It might interest you know that the equipment we were using to code and modulate NICAM in NZ was the brown faced Philips PM5687 I demo'd in the video!
@noahderrington51562 ай бұрын
Have you seen eWasteBen on KZread? He has been picking up loads of historic broadcast gear on his channel
@mattstvbarn2 ай бұрын
Just had a look. Painful to watch things I am looking for being ripped to pieces! Not a great deal of good being in Australia though. Prohibitively expensive and complicated to get things to the UK.
@marria012 ай бұрын
It's times like this I wish I'd paid more attention to the RE DSIS kit I got given for an old work project about 15 years ago. When we determined we wouldn't be able to use it, I think it went into offsite storage and never came back. It's a shame as I think I had at least two encoders and a single decoder. Great video BTW.
@granttaylor36972 ай бұрын
Sound-in-Sync started off gating part analog waveform and therefore had limited audio frequency response, this was well before digital was a thing. The other area from memory, it was used with FMVSB transmissions, to fit into an 8 MHz UHF channel for outside broadcast work.
@jcj834293 ай бұрын
This digital TV (and most modern digital TVs) does a very good job of separating the luma and chroma. For NTSC the picture is almost perfect. Back in the analog days the rainbowing was horrific and we also had dot crawl which is completely absent in this demonstration.
@Catswhiskerdetector3 ай бұрын
Hi Matt. Very interesting video . I'm always amazed by the sheer amounts of hacks and improvement to analog tv, usually in the VBE. I've been messing around with hacktv and it's become quiet apparent just how much analog tv sucks with weak signals and multipath. Really gives you a clear understating of the enormous output power and the many repeater station the big station had. The end-to-end setup with NICAM is pretty neat but I can't help but think that the biggest home market adoption problem is that FM was usually good enough, especially though small and cheap tv speakers. I'm glad I came across you channel, keep it up! :) Jelle
@renejensen56563 ай бұрын
Hii Matt We had those RE encoders and decoders in our OB vans and RF link vans all over here at DR, we used this in the beginning of the 90s, before we moved to satelitte contrib. I actually work together with one of the guys that worked at RE and he was one of the developer of the RE system. He worked there until Barco closed down the Danish division. They also made encoder/decoders that could handle DSIS with other data in the signal such as teletext. When in use the monitoring in the contrib RF link was a bit problematic, since you wasnt able to monitor the regular ITS signals in the signal without a decoder in the RF Link van, because the raw signal hasnt any sync for the monitoring equipment to lock into. But the system encoding was quite robust, even on a bad RF link with noice.
@mattstvbarn3 ай бұрын
Yes I had that problem with syncs. If you need syncs to monitor the input of the decoder, the other problem is the propagation delay of the decoder, in which case you also need an SPG to generate syncs subtracting the decoder delay!
@marria012 ай бұрын
I remember equalising video links at the start of my career, and on a marginal signal we'd often have to tweak the eq to such an extent that by the time the SIS could be decoded, there was usually a load of ringing on all luminance transitions in the picture. The studio would often complain, so you'd offer them the choice of ringing on the picture but usable audio (the subcarrier audio would often be unusable in these sorts of situations, as well), or a decent picture but with no audio.
@paulranson69733 ай бұрын
IIRC 'original' SiS was analogue samples, two per sync pulse. So they could be created and recovered with sample and hold analogue technology, no need for AD/DA or way back then.
@mattstvbarn3 ай бұрын
Which original in particular? From my read of RCA's work, a whole myriad of approaches is described!
@paulranson69733 ай бұрын
@@mattstvbarn I can't answer that precisely.... I worked for the BBC for a while in the mid-80s and we had to go to Evesham to be taught stuff. One of things was SiS, the system we played with was analogue samples at twice line rate. As I never saw this stuff again it's entirely possible memory is faulty... But that aspect has remained clear. I presume this was what the BBC standardised on for distribution prior to the introduction of Nicam and I'm pretty sure it was Designs Department originated.
@paulranson69733 ай бұрын
I cannot find any support for my memory, but the original BBC papers are quite interesting. Sorry for the nonsense.
@marria012 ай бұрын
@@paulranson6973 was that system not VIMCAS or maybe VISCAS? It used to carry a waveform on a couple of lines in the VBS. ISTR OB's used it on contribution feeds for 4 wires/talkback etc. I don't think it was good enough for programme sound.
@AvroVulcanXH6073 ай бұрын
Very nice! Some of the SiS kit we have in Belfast has the Harris branding. Almost all the kit that's still languishing upstairs was used for contribution feeds rather than transmission, and it's all wired for analogue audio! We also have a system for sending NICAM-3 over microwave... but that's another story.
@mattstvbarn3 ай бұрын
Thanks! I do not want to hear that kit has ended up in the trash like the rest of it ;-)
@altebander27673 ай бұрын
Actually it is probably AC coupled, that's probably what causes that awful buzzing noise as it fails during the vertical sync interval.
Пікірлер
This test card used to broadcast on the albanian television during communist times until 2012
This applies to all BE-4 chassis TVs, I did this mod 2 years ago on my KV-M1450E, I got the MC44002 from AliExpress at the time
Do you really have the PM5644 SECAM version? Do you have the PM5644L/00 because I'm ready and want to use it too?
i have windows pc but not linux machine
I've made some progress since I posted the last comment. It works so much better under Linux Mint instead of Windows. I use a HackRF clone that doesn't have that banding issue, fortunately. Meanwhile I've been playing around with the code of both HackTV and HackTV GUI and I've made some changes, I've enabled NICAM on SECAM-BG mode and added PAL60-BG, PAL60-DK, NTSC-BG, NTSC-DK, NTSC 4.43-I, NTSC 4.43-BG and NTSC-4.43-DK modes.
I just tried this also through virtualization, SECAM is impossible for me, UUUUUUUUUUUUUUUUUUUUU starts appearing all over the place and the image is very glitchy, I tried reducing sample rate but no difference PAL test card seem stable but playing a video it also glitches from time to time, any idea on how to avoid this?
I wonder if setting the sample rate to 15.625 would make the bars dissapear completely, I have a HackRF I definately have to give this a try, is there a Windows version?
I find your reasoning at 2'00" - 2'34" a bit obscure. What you are trying to say is that at the time 16:9 content was to be delivered using full existing signal resolution (as opposed to letterboxing) for 16:9 TV-sets, anamorphic was not an option as current 4:3 TV's had no letterbox feature . Hence PALplus was created which is backwards compatible with all 4:3 TV's (showing letterbox format) and still use the full signal for 16:9 TV's. On a side note: letterbox format on 4:3 TV's had already be in use for widescreen movies, before pan & scan became the fashion. After the arrival of 16:9 TV-sets and before, besides and within PALplus letterbox came back. 16:9 TV's lacking PALplus or getting a plain letterbox signal simply upscaled the picture pushing the black bars of of the screen.
When did TVNZ start using nicam ?
For those who remember Grandstand on a Saturday on the BBC, most of the sound from the OB truck was carried over SiS in some form, either via direct video link, microwave or Sat. The sound supervisors all had various ways of pre eq-ing the audio going in the SiS encoder to cope with the detrimental effects of the anti-alias filter and the 10 bit compander. There were complaints that the starter's gun in athletics sounded a bit lacking in 'bang' otherwise. Major OBs would have standard analogue 15kHz music lines provided by the Post Office (BT) with video+SiS as a backup, though for convenience at TVC, quite often the analogue audio circuit would be forgotten about, as the SiS sound was easier the manage with the audio being embedded in the same video. Often at major dual media (Radio & TV coverage) events such as horse racing or rugby internationals it was common for the radio broadcasters use a video circuit with SiS as there was more spare capacity in the video provision. Of course, any BBC piece of audio equipment of that era would have B-gauge (PO316) sockets for audio connections to supplement the XLRs. The entire sound desk patch bay (jackfield) and ancillary racks in the OB truck were PO316. When 'Bantam' mini plugs were introduced in the early 1980s to save space, the reliability of the audio connections went down significantly. Would you need a filter on the DAC output if you are feeding the signal into a line output transformer? I'm guessing a coupling capacitor and the inductance of the transformer would do the job. Transformers are probably manufactured by Sowter BTW.
I will to buy PM5644 also. But model number is PM5644G/00 in 2000 USD
Sorry - bit of a comment stream. Interesting that it's a BBC BASIC running on a Z80, as the BBC Micro was 6502-based (not Z80). However there was a Z80 BBC Basic used for the BBC Micro Z80 Second Processor (and it was also sold for other Z80 platforms). Richard Russell, who worked for the BBC in Designs Dept, developed a lot of in-house equipment, and was heavily involved with the BBC Micro, and keeps BBC BASIC alive across a number of architectures, may be able to advise.
I should have made it clearer when I was mumbling on. The Z80 observation and "BBC Micro" description wasn't intended to refer to the consumer BBC Micro, but rather the ADZE BBC Microcomputer designed by John Robinson, used in various broadcast kit. There is a picture of it on my website: techmattmillman.s3.dualstack.us-east-1.amazonaws.com/wp-content/uploads/2022/08/combiner_pcb.jpg it is the design ancestor of the item I showed in this video. JohnR actually did the handover to TVT for this module.
@@mattstvbarn to help get BBC engineers familiar with the use of microcontrollers in broadcast equipment in the 1980s, part of their training included how to use a small Z80 prototype board, with the usual RS232/422 hardware ports, to make bespoke modules for housekeeping duties such as the monitoring and control of larger items. Programming was usually done in Z80 assembly and figForth.
One other thing I've been told in the past - which may or may not be true - is that the RE DSIS system was easier to remodulate to NICAM and needed less re-framing. It could be that the TVT SiS fixed data burst vs the RE slightly variable data burst is related to this ? (It could be that RE's system requires less buffering?)
B-gauge jacks were standard in BBC analogue audio jackfields and on BBC sound gear - so not surprising they were used on the BBC TVT stuff.
Those reframer interruptions were heard on NICAM whenever a BBC regional centre switched itself into and out of circuit before a regional opt-out (called soft-opting). AIUI the opt-out switch switched between incoming Network with Dual Channel SiS and local studio with its own Dual Channel SiS. Before the actual switch to the regional output, the local studio would have network vision (and decoded dual channel SIS audio) on its sound and vision mixers, and the output of that studio would be Dual Channel SIS encoded. The opt-out switch - that switched the local studio into the transmission path would switch from incoming network with SiS to local studio with SiS (with the local studio carrying the same incoming sound and vision as network). Then when the opt-out was called the local studio would cut away from network sound and vision to local sources for the duration of the regional opt, at the end you'd cut back to network sound and vision, and then the opt-out switch would be moved to take network (with network SiS) clean - and you'd get another reformer interruption.
Interesting. This sounds exactly the same as the situation they had at TV2/DK. Haven't yet heard of any other non-UK examples however. Normally NICAM is just tacked on at the end of the tx chain negating the need for reframers.
@@mattstvbarn Yep - my guess is that it was more used in areas that used PAL composite distribution (the BBC used 140Mbs digital composite circuits to regional centres and then a mix of digital composite fibre and analogue microwave for transmitter distribution) rather than compressed digital component (where you had no real syncs to put sound in?)
I assume the low bitrate speech you mention is the 9.5kbps CELP codec developed for the AUDETEL project. I don't know whether the NICAM additional data version was ever actually used anywhere - the UK audio description trial broadcasts used the even lower bitrate (7.5kbps) teletext transmission version. I would be *very* interested if any of your viewers ever turn up one of those coders, but I fear they're another thing that only existed in single digit numbers of units and have long since been scrapped.
That would be a very interesting thing to find. Knowing what to look for is always a good place to start!
It was developed by the University of Surrey as "Speka Ltd". It seems like the BBC had at least two encoders as they generated audio streams live (frequently we find programme audio from TV or radio channels being routed out). ITV's signals were pre-prepared for playout like subtitles. One of the decoders still exists in Peter Weitzel's collection. Decoding was mostly reverse engineered before we learnt that.
One thing to remember when discussing SIS is that it wasn't limited to use for transmission distribution - BBC Outside Broadcasts (and the EBU) used SIS extensively for outside broadcasts over microwave and satellite circuits - where NICAM 728 compatibility was a non-issue (you would have been going analogue in at the OB end and analogue out at the network centre end - not baseband NICAM or PCM digital) - and having stereo SIS gear to link OBs back to base in stereo was a major requirement (Sony PCM F1s were sometimes used on a second circuit in the very early days I believe, as well as for Radio OBs) The NICAM 3 / 676 stuff may well have been an attempt to solve that problem (ignoring transmission distribution to NICAM 728 TV transmitters) - as you only needed the decoder and encoder at either end to be compatible.
I believe both C4 and TV-am made use of the NICAM spare data capacity for a low-quality talkback channel to outside broadcasts. This makes sense as TV-am was routed directly to the transmitters during their broadcasting hours I believe - and so if the data had been in the SiS distribution it would have reached every transmitter (irrespective of whether the local company had any support for NICAM data talkback?). I have heard reference to it being used for C4 racing - presumably after 1992 when C4 took over advertising playout from the local ITV companies and added their own distribution to transmitters. However I believe C4 moved to 34Mbs compressed distribution around this time too - so it may not have been fully end-to-end SiS? (Was it ETSI compression they used? It was a major reason for them choosing D5 over Digital Betacam as they were concerned about compression concatenation at the time I seem to remember?)
Its likely the bang was the electrolyte across two high voltage tracks and creating a short, as I've experience this in the past and finding no damaged components.
Very interesting! Also, HOLY F..K that PCB burn!!
The fact that people with past involvement and expertise pitch in is fantastic. Super interesting, thank Matt.
Hi Matt, Hello, Today I have something to tell you. Last Monday I will start buying Philips PM5644G/00 Color Pattern Generator. I asked Mr. Kevin Munika, a Kenyan seller on WhatsApp that the price of PM5644 is 2000 USD, if I have the money I will start buying it right away. Thank you
I'd like to reference your S-i-S videos on my website where I discuss it's use with subscription television in the 80s and 90s.
Go for it.
Oooh, now THIS is interesting. I've been fascinated by this for a long time.
so what size cap did you use ?
You can achieve s-video output through the scart socket with a scart to RCA & composite video adapter with an s-video port built in, just use the s-video lead with the red & white audio leads leaving the yellow composite video lead unplugged, or use another screen with composite video output & you can see the comparisons between them in real time.
4:46: "this is a beat pattern which occours between the oscillator in the color decoder and input signal" Could you explain why that happens? Thanks!
Information on the BBC Decoder is on the bbceng info site, under the equipment name CD3/504. Further information can then be found for each sub-module, eg AM1/38, UN16/515, FL1/31 etc. This may not exactly match the Varian unit that you have, but it should be close to the BBC Design.
Thanks for that. Just had a quick look. This appears to be for the old mono system, which actually I have yet to come across such detailed information about! Very interesting...
My first digital capable TV, a 28" 16:9 Hitachi had undocumented analogue capabilities which I discovered using my first analogue and digital satellite receiver. The satellite receiver could send 625/ PAL to the TV whatever satellite signal was being received but could be set to send in NTSC and SECAM as well and the Hitachi TV would accept them. When a NTSC 525line satellite signal was fed to the TV as 625/PAL motion was jerky which cleared when switched to 525/NTSC and a TINT option became available in the TV's settings menu. When the French analogue satellite 625/SECAM signals were seen, text had noticeable colour ringing which I think must be the origin of the STREAKAM nickname for the system.
Thanks for sharing. I have one of these myself that was used by Dutch television in Hilversum. It still works, I only had to replace the bulb in the power switch.
9:10 also Luxembourg nearby border of France, used SECAM-L and also PAL-B/G.
hi,enjoyed your video, .Back i early 1990's i hunted satellite feeds,one saturday night i came across Noel Edmonds show using SiS on their satellite OB, live at a birthday party somewhere in the uk, Noel was in studio dressed as leatherman from the village people, his feed was then fed via Sat and recieved at OB site, mixed with the YMCA video being shown at the birthday party,,Thus, when the man whos birthday it was, got up on stage to do the YMCA carriokee, the screen behind him, then showed Noel joining in......... this was the suprise, when revealed... all done in SIS, i did record all this show using SIS inserter decoder,, its on Vhs somewhere..... must look.for it..👍
25:50 - This rings a very vague bell; is it possible that the low-quality audio feed was some sort of comms circuit? As a Cameraman I was never involved with TX/RX hardware; but I recall seeing feeds with tinny telephonic-sounding gallery audio on them which was (I recall being told) sent 'SIS'.
Hi Matt. In 1990 I worked for a company in Melbourne Australia supporting re 140Mbps Video CODECs(8:00). I spent some time in Copenhagen training at re. They were great folks. You're right, their documentation was outstanding as was their engineering. I do remember learning about their SIS but never used it in Australia. They had broadcast quality audio coders (15kHz?) that would interleave data into slots in the 140Mbps stream and I believe there was room for 2Mbps data as well. The 10 bit video sample rate was locked to 3 times the colour subcarrier and there was some very clever padding and frame size manipulation to sync with the 140Mbps data stream. Varying the SIS data rate as you mentioned would be consistent. Pseudo random encryption was not primarily for security but rather to prevent dc offsets occuring as a result of repeating bit patterns during static video scenes. I'd love to get hold of a TxRx pair. Thanks for the video. Was a real nostalgia trip.
Glad you enjoyed it. Would love to get a pair of those codecs on the channel. That particular coder is surviving but all of the decoders had been scrapped unfortunately.
I have a copy of the user manual as a PDF that you can have. You will be able to do more experiments and even get into the monitoring software that drives the error LEDs. I have a Harris badged coder and a TVT decoder saved from the skip. The open frame construction always made me nervous when working in racks with this gear in.
Brilliant. I look forward to seeing it. I think the open frame construction made sense in terms of how it was deployed. Very good for airflow, just a bit fragile when used standalone. I believe there was an official ruggedised case for the equipment for cases where it had to be used standalone!
Many thanks for that. No circuit diagrams in that manual I take it?
Just wondered if you had seen the response I sent to your email on Tuesday? On my end I had noticed that your message ended up in my junk folder for some reason!
Very interesting fun! Shows again the robustness of Nicam! There’s an interesting BBC R&D report from 1966 comparing the relative goodness of using various pulse techniques to carry sound in sync (1966/58). They compare PCM (which obviously won) with PAM, PWM and PPM. There doesn’t seem to be any indication that any of these other SiS techniques were actually in use though. In the references there are references to a paper about the French 819 line system muxing sound. Has anyone ever seen this fabled HD system from the 1960s?
TVNZ enabled the NICAM 1988 I believe. It was very gradual and it was mostly just mono on the stereo NICAM channels. I think it was originally just Shortland Street, some commercials and a late night music show that we're actual stereo for quite a long time. TV3 launch in 1989 was first to go full time stereo and was amazingly exciting time for a tech geek. Probably easier for TV3 S starting with new infrastructure rather than having to retrofit. I purchased a Mitsibishi E70 VCR and recall paying about $500 just to get the optional NICAM decoder module installed before any NZ broadcasting. Was pleased when it started getting some use. :)
It was my understanding that it didn't officially launch until 1989? It might interest you know that the equipment we were using to code and modulate NICAM in NZ was the brown faced Philips PM5687 I demo'd in the video!
Have you seen eWasteBen on KZread? He has been picking up loads of historic broadcast gear on his channel
Just had a look. Painful to watch things I am looking for being ripped to pieces! Not a great deal of good being in Australia though. Prohibitively expensive and complicated to get things to the UK.
It's times like this I wish I'd paid more attention to the RE DSIS kit I got given for an old work project about 15 years ago. When we determined we wouldn't be able to use it, I think it went into offsite storage and never came back. It's a shame as I think I had at least two encoders and a single decoder. Great video BTW.
Sound-in-Sync started off gating part analog waveform and therefore had limited audio frequency response, this was well before digital was a thing. The other area from memory, it was used with FMVSB transmissions, to fit into an 8 MHz UHF channel for outside broadcast work.
This digital TV (and most modern digital TVs) does a very good job of separating the luma and chroma. For NTSC the picture is almost perfect. Back in the analog days the rainbowing was horrific and we also had dot crawl which is completely absent in this demonstration.
Hi Matt. Very interesting video . I'm always amazed by the sheer amounts of hacks and improvement to analog tv, usually in the VBE. I've been messing around with hacktv and it's become quiet apparent just how much analog tv sucks with weak signals and multipath. Really gives you a clear understating of the enormous output power and the many repeater station the big station had. The end-to-end setup with NICAM is pretty neat but I can't help but think that the biggest home market adoption problem is that FM was usually good enough, especially though small and cheap tv speakers. I'm glad I came across you channel, keep it up! :) Jelle
Hii Matt We had those RE encoders and decoders in our OB vans and RF link vans all over here at DR, we used this in the beginning of the 90s, before we moved to satelitte contrib. I actually work together with one of the guys that worked at RE and he was one of the developer of the RE system. He worked there until Barco closed down the Danish division. They also made encoder/decoders that could handle DSIS with other data in the signal such as teletext. When in use the monitoring in the contrib RF link was a bit problematic, since you wasnt able to monitor the regular ITS signals in the signal without a decoder in the RF Link van, because the raw signal hasnt any sync for the monitoring equipment to lock into. But the system encoding was quite robust, even on a bad RF link with noice.
Yes I had that problem with syncs. If you need syncs to monitor the input of the decoder, the other problem is the propagation delay of the decoder, in which case you also need an SPG to generate syncs subtracting the decoder delay!
I remember equalising video links at the start of my career, and on a marginal signal we'd often have to tweak the eq to such an extent that by the time the SIS could be decoded, there was usually a load of ringing on all luminance transitions in the picture. The studio would often complain, so you'd offer them the choice of ringing on the picture but usable audio (the subcarrier audio would often be unusable in these sorts of situations, as well), or a decent picture but with no audio.
IIRC 'original' SiS was analogue samples, two per sync pulse. So they could be created and recovered with sample and hold analogue technology, no need for AD/DA or way back then.
Which original in particular? From my read of RCA's work, a whole myriad of approaches is described!
@@mattstvbarn I can't answer that precisely.... I worked for the BBC for a while in the mid-80s and we had to go to Evesham to be taught stuff. One of things was SiS, the system we played with was analogue samples at twice line rate. As I never saw this stuff again it's entirely possible memory is faulty... But that aspect has remained clear. I presume this was what the BBC standardised on for distribution prior to the introduction of Nicam and I'm pretty sure it was Designs Department originated.
I cannot find any support for my memory, but the original BBC papers are quite interesting. Sorry for the nonsense.
@@paulranson6973 was that system not VIMCAS or maybe VISCAS? It used to carry a waveform on a couple of lines in the VBS. ISTR OB's used it on contribution feeds for 4 wires/talkback etc. I don't think it was good enough for programme sound.
Very nice! Some of the SiS kit we have in Belfast has the Harris branding. Almost all the kit that's still languishing upstairs was used for contribution feeds rather than transmission, and it's all wired for analogue audio! We also have a system for sending NICAM-3 over microwave... but that's another story.
Thanks! I do not want to hear that kit has ended up in the trash like the rest of it ;-)
Actually it is probably AC coupled, that's probably what causes that awful buzzing noise as it fails during the vertical sync interval.