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  #1  
Old 09-30-2015, 06:41 PM
RJMiranda RJMiranda is offline
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BVW70 just picked in Havana

Hi, guys. Look at what I found!
Let me explain to you that getting an old VTR in my country is not the easy thing it looks everywhere else.
First, for the time being we still use Standard Definition TV (NTSC, that is) so this gear, if working, is not going to appear in a "old-stuff" sale.
Second, we donīt have any "old-stuff" sale either, and very often the owner keeps old equipment for spares instead of getting rid of it.
Cuban TV still uses this model of VTR (and the not-so-strong PVW-2800) for its daily programming!
That said, a friend that works for a foreign press agency, who knows I hate to see broadcast equipment being junked, told me several months ago there were at his workplace a couple of VTRs nobody wanted. Yesterday he called me again, and this is what I got.
The other VTR is a Sony UMatic BVU-800. It looks fair on the outside, but it does not power up. Looks like a dead power supply. I have the service manual, some day I will give it a try.
But this Betacam baby is almost working! A cassette was stuck inside and there was no communication between the control circuit and the front panel, but it is already working!
The machine has seen a lot of work (it shows) but every button lights, tape transport works as new, and RF PB level is good and healthy. (I have not yet tried to record).
Only thing is with the chrominance channels. Only PBs in black and white with occasional color noise. Tomorrow will look at it with a scope. Donīt seem to be faulty heads.
I want this VTR to digitize original works (music videos, short and long-form fiction, documentaries) made by Cuban independent filmmakers between 1980-2000, before the tapes get lost.
Betacam color CTDM circuits are highly complex... letīs see. Wish me luck!
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File Type: jpg BVW70 Cuba.jpg (138.2 KB, 48 views)
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Old 09-30-2015, 10:26 PM
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baursam baursam is offline
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Best of luck indeed! A very good chance Ill be down in Havana in late November to see your wonderful city!! When I found out shortly if its for sure that Ill be there, Ill let you know. Funny thing I was just thinking about early Cuba television.
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Old 10-01-2015, 07:56 AM
RJMiranda RJMiranda is offline
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Early Cuban TV

Well you can say that we still use "early" TV because we are not in HD. We are implementing terrestrial digital SD broadcasting, and in the near future will start some HD programming. But not for now.

We still have just one HD-equiped OB-van. No HD studio cameras (altho some news gathering is made with HD gear set to record in SD, because you can not find SD cameras outside a museum).

It is like in the mid-seventies, when we had just a Nec-made OB-van and it was the only color unit in Cuba. When a program was to be broadcast in color, the truck was parked alongside the studio building, cables run up the stairs to the studio, and the Russian/DuMont/RCA B/W cameras pushed aside.

Cuba had color TV in late fifties, earlier than many countries. Some say that we were second after the US. But it was only one channel that broadcast color movies. They had just a telecine and some say one camera for televising the host between movies. They didnīt made any production of their own. It ended broadcasting soon after the Revolution, for lack of spares.
We kept using US-made B/W cameras well into the seventies. The 4 1/2 inch superorthicons came from the USSR, custom-made for the US cameras.

In the mid-eighties we went fully into color. For many years, most of the cameras were Sony DXC-M3 and M3A. And a Magnolia Soviet-made studio that our engineers transformed from 625-line SECAM into 525-line NTSC. Talk about easy tasks!

The recordings were made mostly in UMatic (until about 2003!) and some Sony C-format. Now we use Beta SP and our main TV archives are in that format.

I keep an archive of independent-made programming from 1988 to mid-2000s, mostly from people working at State-owned facilities but not related to the Cuban TV. Now there are many independent artists that own their own gear, but in the eighties you had to borrow State-owned equipment. Many are very interesting works.

I have the only surviving copy of many of these early works, some even made in VHS by art students that today are known film directors. (At the art school, the equipment was then Super VHS, but they used VHS tapes). And a lot of Umatic tapes that are gradually being converted into digital.
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Old 10-04-2015, 07:36 AM
kf4rca kf4rca is offline
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Thats an SP machine...

meaning it will take the metal tapes giving it a superior performance in s/n ratio.
The non SP machines would not take the larger 2 hr tapes. There are plenty of those since they were popular with the news crowd where segments are 20 mins or less. And all the camcorders of the time would only take the small tapes.
Also that machine does not have DT or dynamic tracking allowing a still frame of video in pause.
If the chrominance heads are bad you will get color flashing. If colors are screwed up, its most likely a bad color filter. There are several of those thruout the machine. They look like a small silver module. They are pricey but most stations fixed them. The problem is that the adhesive glue becomes conductive.
You will have to scrape the glue off them with an exacto knife (and xylene to soften up the glue). Its about a 1 hour process. Then touch up the circuits with a soldering iron and reassemble. There was a bulletin about this.
As I remember, Sony sent a letter out to stations that they were no longer going to support analog products about 10 years ago. So parts might be difficult to find.
If you need an upper or lower drum, AHEAD TECHNOLOGIES used to sell rebuilt ones. Good luck.
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Old 10-04-2015, 11:49 PM
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baursam baursam is offline
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I don't believe the embargo is officially over. Hopefully, its just a matter of months, but if there is a part you have located in the US that you need but are unable to purchase/have it shipped to you due to your location, let me know and i could assist from up here in Canada.
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Old 10-05-2015, 01:17 AM
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fsjonsey fsjonsey is offline
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Quote:
Originally Posted by baursam View Post
I don't believe the embargo is officially over. Hopefully, its just a matter of months, but if there is a part you have located in the US that you need but are unable to purchase/have it shipped to you due to your location, let me know and i could assist from up here in Canada.
The embargo isn't officially over but it has gotten significantly easier to ship small packages to Cuba in the last year or so.

Also, RJMiranda, I just wanted to pop in and say Hello. I work in the retail cigar business here in the USA as a day job, and as a result, do business with a lot of wonderful people from your country. Some of them left Cuba 50 years ago, others as recent as 2012.
At some point, if you're willing, I'd love to hear about what Cuban techs and engineers had to do to keep stuff working post-embargo with a mix of US and Soviet made components, because I use a lot of ebay sourced USSR military surplus passive components, tubes, and transistors myself. Both of my working Zenith mid 60's tube color sets have IF strips full of 6J51P and 6K13P tubes, and USSR made paper in oil caps work great in tube radios and audio equipment.
Anyway, sorry for the thread derail.
If you ever need anything, I have a good friend, a College professor who was my department faculty advisor, that travels to Havana pretty regularly and would probably be more than happy to bring some small parts down for you. He's a part of a non-profit organization that deals with the preservation of Cuban architectural history. They just opened an office in Miramar, or Vedado, I can't remember which, this past spring. I may be traveling to Havana with him sometime next year. If I do, It would really neat to meet a fellow VK'er in Cuba.

Last edited by fsjonsey; 10-05-2015 at 01:53 AM.
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Old 10-05-2015, 07:54 AM
kf4rca kf4rca is offline
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More...

If you have no color, that is probably bad caps in the chrominance circuits. Try this. Take a blanket and put over the machine for 30 minutes. EE bars thru the machine (no tape inserted, stop mode) and I bet the color will "pop" in. Caps have a tendency to go back to work when they are warm. Many machines were 24/7 machines so stations never knew if they had bad caps. I'll have to look at my notes to tell you which caps they are but as I recall its about 4 small caps will get you going.
DON'T EVEN THINK about removing the head drum UNLESS you have an eccentricity gauge. If your eccentricity is out, you will get noise banding in the middle of the picture. Beta drums are slightly larger than where they mount. Not like VHS. There is no dihedral adjustment. TBC takes care of that.
If the display on the keyboard freezes intermittently, you've most likely got a stuck button on the keyboard. Most likely the "in" or "out" buttons. The buttons are notoriously crappy. Be careful changing buttons out. The circuits pull of really easily. Its not unusual to see jumpers on the bottom of the keyboard.
You should try to get the 2 manuals for the machine. Look on Ebay. There is a set of three extender modules. More tomorrow.
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Old 10-05-2015, 08:12 AM
RJMiranda RJMiranda is offline
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Thank you very much kf4rca for your technical advice (yesterday and today).
The trouble seems to be in the heads/preamplifier because one RF chroma packet is missing. So I will not be dealing with the filters. But it is good to know. Also about the capacitors behaving badly while cold.
Also thanks a lot to baursam and fsjonsey for replying. I am relatively new to VK and will welcome any colleague visiting Cuba.
I will let you know f I need some part brought to Cuba, paying for it of course!!!
Small packages can be also sent by mail. But I havenīt get to that point yet.
I downloaded the BVW-75P service manuals from a Hungarian site called elektrotanya. I strongly recommend it to all of you, and will start another thread so many VKers become aware of it. Absolutely free (thatīs a good thing for someone without a credit card account, yes, that still happens in this world).
At elektrotanya there are mainly European service manuals, of course. But the second volume (the one with the schematics) happened to be NTSC.
I know my machine is a 70 and not a 75, but about 80% of the boards are shared among these two machines, and the ones I need are in the 75īs manual. So, later today I am going to dig with my scope, maybe swapping the identical RF preamplifier boards among Y and C channels, and so will know if the trouble is in the heads or in the electronics.
If the heads are damaged it will be more difficult, but maybe I can find them in Cuba. I have the eccentricity jig (the same used for the UMatics). After that the electronic alignment will be a slow process, but with help from Cuban TV (they have the alignment tapes, extender boards and so on) it can be done.
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Old 10-07-2015, 04:36 PM
RJMiranda RJMiranda is offline
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Not the heads!

The heads were not guilty! (I suspected that because the tapes recorded in the machine did PB in color in another VTR). With the aid of the service manuals I got from elektrotanya, I did trace the PB signal. Near the head drum there are PCBs for the REC RF amplifiers and PB RF preamplifiers (much like the circa-1968 1Ļ open-reel Sony EV-300 series). But in the Betacams there are two boards, because the format uses separate pairs of heads for luminance and chrominance.
The four RF packets come out alive and well from these boards. One of the channels in the chrominance system has a slightly lower level, nothing that can not be adjusted later. But the trouble is in the DM board that comes later in the chain.
In this board the signals from the heads are selected (the 70 has TWO pairs of heads for each luminance and chrominance, the second pair is the "confidence" head while recording).
The process is the same both for Y and C circuits. After selected, the PB/Confi signals are amplified and DC-corrected, and then switched so the "active" headīs signal is further processed.
In the Y circuit I get both A- and B-channels perfectly, but in the chroma path only the A-head signal is present.
So the trouble lies between the input of the MD board and the test point I am measuring from.
These test points are located (very cleverly) at the edge of the board, so they are accessible without removing it.
I donīt yet have the extender board that will allow to operate the machine with the MD board out of its slot, so will have to wait until I get the extender board. Then I will have access to the full surface of the board.
I could solder temporary long wires from the points I want to measure from, reinsert the board and take the measurements from the wires, but with so much soldering and resoldering I could easily ruin the board. I am not taking chances with this machine.
So for the time being, I will put myself in a brief "stand-by off" mode. I will let you guys know very soon how this story ends.
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Old 10-12-2015, 04:49 PM
RJMiranda RJMiranda is offline
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Repaired!

The good VTR maintenance guys at Cuban TV lent me an extender board. As soon as I put the suspected demodulator board on the extender, I noticed the missing RF signal didnīt even got to it. So it was not the DM-boardīs fault after all.
At the bottom of all these VTRs there is a motherboard that interconnects the different PCBs. I followed the signal path from the preamplifier board (that was working perfectly up to the output connectorīs pin) to the motherboard. The connecting cable was not at fault. The motherboard looked OK even at a close inspection: the soldering points looked well, the board was not bent/cracked/damaged, even the varnish was like new... but it measured open and the ohmeter doesnīt lie. So I soldered a little white jumper in place and presto!
It is the first time in my experience of many years that I have found this kind of trouble in a professional studio VTR. Maybe in a field camera that may get banged accidentally... but this VTR does not show any kind of external damage, and its four legs sit flat against the table... not as if it had been dropped sometime so damaging the circuit.
Letīs hope that this VTR has not additional occult troubles like this. We have a very saline atmosphere in Cuba, but no other Betacam or even UMatics that I know of has had corroded circuits (and as I say, the varnish looks pristine).
Well, it is working perfectly now... thank you very much to all VKs/visitors that looked, and specially to baursam, kf4rca and fsjonsey for their offerings and valuable advice. If coming to Cuba, let me know!
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File Type: jpg Jumper.jpg (127.2 KB, 20 views)

Last edited by RJMiranda; 10-12-2015 at 04:51 PM. Reason: Reload attachment
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Old 10-12-2015, 11:16 PM
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Robert Grant Robert Grant is offline
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Yes, it is widely agreed that Cuba was second behind the USA in regular color TV broadcasts.

The Canadian government kept broadcasts in monochrome until 1966. When independent CFTO (9) came on the air in Toronto in 1961, it was completely equipped with color gear - but turned the color signal off. It appears that the government public broadcaster (CBC) had just spent millions getting their monochrome signal across their very vast country, and were afraid if independents went color, CBC would be expected to do a complete rebuild for color. They were kind of forced to give in when they did when Canadian viewers near the US border (MANY Canadians are) were watching USA (e.g., Buffalo and Detroit) stations to use the color TVs they had brought across the border. The second country to launch a broad color TV rollout was Japan, in 1960.

I'm very curious about the history of Habana's Canal 12 (I've heard it was called "Tele-Color S.A." and/or had the clever call sign COLOR, as the CO call sign block is allocated to Cuba).

Yes, it is quite obvious that Cuban analog TV is still going. Since the full-power analog transmitters in the US closed in June, 2009, and VERY few broadcasters chose to use lowband VHF for their digital transmitters, Cuban TV signals are seen far more frequently when sporadic-E ("VHF short skip") conditions permit. CMBA is very easy to recognize, as it is Tele-Rebelde and minus offset (55.24 MHz video). Some US TV DXers even call it a "pest"!
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Old 10-17-2015, 04:23 AM
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fsjonsey fsjonsey is offline
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Quote:
Originally Posted by RJMiranda View Post
The good VTR maintenance guys at Cuban TV lent me an extender board. As soon as I put the suspected demodulator board on the extender, I noticed the missing RF signal didnīt even got to it. So it was not the DM-boardīs fault after all.
At the bottom of all these VTRs there is a motherboard that interconnects the different PCBs. I followed the signal path from the preamplifier board (that was working perfectly up to the output connectorīs pin) to the motherboard. The connecting cable was not at fault. The motherboard looked OK even at a close inspection: the soldering points looked well, the board was not bent/cracked/damaged, even the varnish was like new... but it measured open and the ohmeter doesnīt lie. So I soldered a little white jumper in place and presto!
It is the first time in my experience of many years that I have found this kind of trouble in a professional studio VTR. Maybe in a field camera that may get banged accidentally... but this VTR does not show any kind of external damage, and its four legs sit flat against the table... not as if it had been dropped sometime so damaging the circuit.
Letīs hope that this VTR has not additional occult troubles like this. We have a very saline atmosphere in Cuba, but no other Betacam or even UMatics that I know of has had corroded circuits (and as I say, the varnish looks pristine).
Well, it is working perfectly now... thank you very much to all VKs/visitors that looked, and specially to baursam, kf4rca and fsjonsey for their offerings and valuable advice. If coming to Cuba, let me know!
RJMiranda, I'm glad you got it working!
I've spent the night working on recapping this:

While smoking a few Bolivar Royal Coronas.

I was at my Cousin's wedding earlier this afternoon and handed out about five or six of them. They had it in a rustic lodge in a state park here in Ohio. The Aroma of the Bolivars went great with the smell of the fireplace burning. As you probably know, Cuban Cigars are coveted by Americans that don't usually smoke cigars. They have no idea how easy it is to get them, forbidden fruit and all.
One more quick question. Are there any Chevy Corvairs running around in Havana still? I just finished restoring a 1962 Corvair Monza 900 4 Door sedan this spring. Unfortunately, a Drunk Driver decided to plow into it back in late August.


The drunk who hit me was found liable and his car insurance is going to pay to fix it, but it's still a shame. This was a spotless, rust free car from Arizona.

Last edited by fsjonsey; 10-17-2015 at 04:41 AM.
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Old 10-19-2015, 04:45 PM
RJMiranda RJMiranda is offline
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Hi fsjonsey! Great looking TV, good job!
I am very sorry about what happened to your Corvair.
There are some Corvairs in Havana (I canīt tell you much about other provinces) but MOST of them have replaced the original engine with a Russian Lada 4-cyl mounted at the front. Donīt ask me what they did to the steering system, nor how they mounted the engine without proper reinforced surfaces. And of course they had to open a ventilation grille between the headlights and run the transmission shaft to the rear axle.
All said, they donīt look half as bad as it sounds... except that I LOVE to see older cars running as they were made.
I have a 1953 Chevrolet Belair (it needs a new front grille because the original one rusted apart), but with the original engine and transmission. Only change is an alternator instead of a DC generator.
The Corvair is a beautiful, unique American car. I think it is the ONLY 6-cyl H-engine ever made. Maybe they made it after the Volkswagen, air-cooled, rear-engine, but being American it had to have 6-cyl power!
A friend of mine here had a Corvair with automatic transmission, but after so many years it was worn, and after 30-40 mins of driving, it wouldnīt shift to high!
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Old 10-29-2015, 03:05 AM
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fsjonsey fsjonsey is offline
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Originally Posted by RJMiranda View Post
Hi fsjonsey! Great looking TV, good job!
I am very sorry about what happened to your Corvair.
There are some Corvairs in Havana (I canīt tell you much about other provinces) but MOST of them have replaced the original engine with a Russian Lada 4-cyl mounted at the front. Donīt ask me what they did to the steering system, nor how they mounted the engine without proper reinforced surfaces. And of course they had to open a ventilation grille between the headlights and run the transmission shaft to the rear axle.
All said, they donīt look half as bad as it sounds... except that I LOVE to see older cars running as they were made.
I have a 1953 Chevrolet Belair (it needs a new front grille because the original one rusted apart), but with the original engine and transmission. Only change is an alternator instead of a DC generator.
The Corvair is a beautiful, unique American car. I think it is the ONLY 6-cyl H-engine ever made. Maybe they made it after the Volkswagen, air-cooled, rear-engine, but being American it had to have 6-cyl power!
A friend of mine here had a Corvair with automatic transmission, but after so many years it was worn, and after 30-40 mins of driving, it wouldnīt shift to high!
RJMiranda, I had a feeling that most of the Corvairs left in Cuba had been converted to Lada or Moskvich power. I would love to see how they made that work, haha.
The Corvair engine has sort of a unique back story. Ed Cole, the head of Chevrolet, and father/champion of the Corvair, was an accomplished Civil Aviator. He was quite familiar with the flat-six Franklin and Lycoming engines in the aircraft he flew, and knew that American car buyers wouldn't accept the roughness of Volkswagen's flat four in an American car. The Corvair engine shares more with small aircraft engines of the era than anything else. Chevy had an air cooled flat-six engine in mass production 6 years before Porsche debuted the first 911.

Quote:
Originally Posted by RJMiranda View Post
A friend of mine here had a Corvair with automatic transmission, but after so many years it was worn, and after 30-40 mins of driving, it wouldnīt shift to high!
Also, it's too bad about the Powerglide in your Friend's Corvair. It was probably something as simple an a broken E-Clip or at worst a $30USD Vacuum Modulator. The Corvair Powerglide is almost indestructible. They were so reliable, in fact, that GM never issued a full rebuilt kit for them. I've seen a few that outlasted being swapped into five or six cars.
http://corvairfleet.blogspot.com/201...es-e-clip.html

Oh, one last question. Did imports of American cars cut off in the 1960 or 1961 model year? I've seen some photos of Corvairs in Havana that look suspiciously like 1961 models.
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Last edited by fsjonsey; 10-29-2015 at 03:36 AM.
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Old 11-16-2015, 06:49 PM
RJMiranda RJMiranda is offline
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Hi, fsjonsey!

I havenīt seen how exactly they put a Lada engine into a Corvair. I am really curious, but havenīt had the chance of seeing one with the hood open.

Of course they put the Lada engine on the front (and have to open a grille, thatīs how you can know they are converted Corvairs). They somehow modify the floor to run the transmission shaft to the rear axle, which is (of course) Lada.

I donīt remember the exact date of the US embargo. (1962, I think). Of course the day after that you couldnīt send a nail to Cuba! But I am told by older people that American cars were sold in Cuba even before than in the US, maybe so they could test them before the beginning of the actual model year. If that is true, the sellers could have some cars of the next model year at the time the embargo came into force.
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