Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently May Sat 30, 2020 12:24 am


All times are UTC [ DST ]





Post New Topic Post Reply  [ 55 posts ]  Go to page 1, 2, 3  Next
Author Message
 Post subject: First generation TV transmitters
PostPosted: Mar Thu 26, 2020 2:56 pm 
Member

Joined: Jan Mon 28, 2013 9:35 pm
Posts: 1600
Location: Santa Rosa, CA
This is a follow up to the 'studio B&W camera' thread.

Wondering if any collectors have been able to save any of the first
generation of TV transmitters (1940's)?

People, mostly hams, have saved and are now using vintage AM broadcast
transmitters on the ham bands. Just wondering if the same is true for TV?
Steve

_________________
'cell phones and the internet are tools, not a lifestyle'


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Thu 26, 2020 3:47 pm 
Member
User avatar

Joined: Nov Thu 11, 2010 6:03 pm
Posts: 1224
Location: Pewaukee, WI
Don't know where you place first gen (mechanical TV, pre-WWII electronic, post WWII), but the early television museeum in Ohio has an IIRC 50s transmitter on display...


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Thu 26, 2020 4:00 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 940
Location: Pasadena CA USA
I have a tube from the RCA water cooled TT-5 transmitter and probably could have had the rare TT-2 complete transmitter if I would have asked nicely, but did not have room for it.


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Thu 26, 2020 10:45 pm 
Member
User avatar

Joined: Aug Thu 12, 2010 6:25 pm
Posts: 350
Location: Durham, NC
The ETF museum has an RCA TT-5A on display: https://www.earlytelevision.org/rca_tt-5a_transmitter.html
There are several TV museums and collections around, though most of them concentrate more on the cameras and receivers. Like those who collect quadruplex videotape machines, collecting even one TV transmitter takes a special kind of person!

_________________
Mark Nelson
A collector of TV signal boosters and UHF converters -- God help me!
tv-boxes.com


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 1:30 am 
Member

Joined: May Sun 07, 2017 11:35 am
Posts: 840
Location: Belrose, NSW, Australia
That transmitter at the ETF is amazing. A big but effectively very simple piece of gear that I thought (but not so) started life on top of the Empire State in NY. The linear amplifier that was used with it is quite unusual in its build concept.

I had the good fortune to have the museum to myself for the best part of a day some years back, when passing through mid-week on a road trip across the US of A. Hearing I was visiting from Australia, Steve just turned up with the key and let me in!

What can you actually do with a vintage analog TV transmitter? You certainly can't switch it on!

Which reminds me:

Back in the 70's TCN9 in Sydney had a sudden, catastrophic failure of their main vision router during peak viewing time. After half an hour or so they were able to go back on the air by manually patching everything - imagine the stress! Missed cues on commercials etc. VERY embarrassing for the number one TV network in the country!

The station had a very hand's on owner - the larger-than-life character Kerry Packer - you may have heard of him, for a time, I think he was Australia's richest man. TCN9 was his baby. He had his office at the station and would commute to his Palm Beach pad daily by helicopter - he'd fly over our place, so we knew he worked long hours.

Anyway, he apparently thundered that this must NEVER happen again for ANY reason. Heads will roll! EVERYTHING must be duplicated and even triplicated.

So, late one night, on Packer's orders, began the attempt to bring up the station's long-disused B&W transmitter as a 3rd-tier backup.

It was interesting to watch. It seemed to start up OK and was looking reasonable on the PM5544 test pattern then horrible-looking things started to go wrong.
I think they gave up in the end.
I've often wondered - was that the original 1956 transmitter?

_________________
Wax, paper, bitumen, cotton, high voltages - what could possibly go wrong?


Last edited by irob2345 on Mar Sat 28, 2020 12:17 am, edited 1 time in total.

Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 3:46 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 1687
Location: Phoenix, Arizona
Back in the 1980's, the TV station I was Chief of had an RCA TT-5 as well as an RCA TT-10 transmitter installed in a mountain top site in Salt Lake City Utah. We had moved on to a new transmitter site on an even higher elevation site.

The TT-5 would have been operational and we actually fired it up a couple of times but the cooling system had been frozen and wouldn't hold water for long.

The 8D21 Finals (most water cooled tube ever) are in the hands of collectors.

We actually reworked the TT-10 with remote control and we ran that on the air occasionally into the late 1990's. It had been upgraded to pass color. All tubes.

I am using some of the 6BG6 tubes from the modulator in a couple of my old TV's

This station was on the air in 1948 using Iconoscope cameras that were originally part of the 1939 TV Exhibit.

These transmitters were so large that it would have been very difficult to stash in a garage.

There was that story of a guy who had stashed a steam locomotive in his barn that was supposed to be scrapped.

Some of this story is posted on the ETF site.

Jim


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 4:36 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 940
Location: Pasadena CA USA
I used to work at a station that had a TT-5 that had been converted to air cooling. This was the backup transmitter and we only had it on the air once a week for testing. I was given an 8D21 and the water flow interlock assembly as a souvenir. I wish I would have taken the entire tube shelf to make a nice display. I worked for two different TV stations that had TT-5s, when the first station got rid of the TT-5 they gave all spare parts to the second station. When the second station converted to air cooling, all the removed parts were stored. One day I came to work and the chief said he had a gift for me and he gave me the 8D21 because it came from the same station I did!


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 5:55 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 1687
Location: Phoenix, Arizona
Here is a picture of an RCA TT-5 Television transmitter.

Nominal Visual power of 5 kW, all tubes, Channel 2 through 13 VHF.

There was a set of large heavy transformers besides the main rack as well as a water cooling unit that was the heat exchange'r had to be outside.

The RF plumbing included a Filter / Combiner and a Side band Filter and of course you needed an antenna on a tower.

If the studio was not near the transmitter you needed a microwave link.

The pic is from a 1950 RCA catalog I have. RCA made every needed item to run a radio or TV station except the slicked up news anchor.

jim


Attachments:
TT5.jpg
TT5.jpg [ 522.86 KiB | Viewed 1258 times ]
Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 6:12 pm 
Member
User avatar

Joined: Nov Thu 11, 2010 6:03 pm
Posts: 1224
Location: Pewaukee, WI
There is one application in the US where a tube TV transmitter could be put to air unmodified legally. Currently there are still a number of ch6 analog TV transmitters on air. CH6's audio carrier lines up with the bottom of the FM band and many FM radios can tune it. Chicago (87.7 MeTV FM audio can often be DX'ed here), LA (or wherever shango66 lives) and a number of other markets still have an analog channel 6, and from what I've heard (and seen from YouTube videos by local TV collectors) they have to transmit both video and audio to opperate in that frequency.


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Fri 27, 2020 6:26 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 1687
Location: Phoenix, Arizona
I am aware of the channel 6's I believe they usually put up an ID slide with a Pong Game for video. Nobody sees the video. Hip-Hop on the aural. They don't care about the TV viewer only the FM radio in a car.

I don't know exactly what happens to the 6's under Re-pack. Since spectrum has become more valuable now that we only have channels 2 through 36. In my market there is about two channels vacant. Wireless Mic's and IFB's usually want to be on a TV channel as well as a lot of medical eqjuipment.

I believe most ran a modern transmitter, some of which still use a final PA tube.

I spent last weekend replacing a final PA tube in a Digital TV transmitter that is on the air now full power.

Jim


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 12:41 am 
Member

Joined: May Sun 07, 2017 11:35 am
Posts: 840
Location: Belrose, NSW, Australia
Have a look at this! It's worth watching all the way through if you can put up with the boy-scout style of the commentator!

https://www.youtube.com/watch?v=mR_wJkxKSXU

I didn't realise until I saw this that, during the last years of analog TV, all 5 major networks in Sydney transmitted from this site - Mowbray Rd & Pacific Highway.. The Gore Hill and Artarmon towers are effectively redundant.

_________________
Wax, paper, bitumen, cotton, high voltages - what could possibly go wrong?


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 1:41 am 
Member

Joined: May Sun 07, 2017 11:35 am
Posts: 840
Location: Belrose, NSW, Australia
Here is an AWA TVB-10 transmitter, made in Australia in about 1960:

https://collection.maas.museum/object/547270

This picture looks like it would have been taken where it was originally installed. Much less cluttered environment!

_________________
Wax, paper, bitumen, cotton, high voltages - what could possibly go wrong?


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 2:07 am 
Member
User avatar

Joined: Mar Sun 01, 2009 10:27 pm
Posts: 5327
Location: Ann Arbor, MI
jimmc wrote:
We actually reworked the TT-10 with remote control and we ran that on the air occasionally into the late 1990's. It had been upgraded to pass color. All tubes.

What type of modifications were necessary to get a black and white transmitter to pass color?
Could a color transmitter be upgraded to transmit digital?
And was the sound transmitted by what was effectively a separate transmitter even if it was in the same cabinet as the video transmitter?

_________________
Tom


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 2:57 am 
Member

Joined: May Sun 07, 2017 11:35 am
Posts: 840
Location: Belrose, NSW, Australia
Well I'm told that ATN7 upgraded their AWA TVB-10 for colour in the 70's by fitting bigger high-level modulator tubes that had to be horizontally mounted in order to fit in the rack - not good for directly heated cathodes! Slew rates at high modulation frequencies were the reason.

In the TV service shop where I worked we used to notice the slow degradation of the modulator's performance on the test card of a morning, over a few months. The black to white transitions would lose their sharp edges. We could tell when a fresh set of tubes was installed because suddenly, one morning, the edges were sharp again! Reason, I heard, was the horizontal mounting.

TEN 10, at the same site, failed with their attempt at an upgrade and bought a new NEC. As did ATN 7 a few years later. You can see the NEC they replaced the TVB-10 with in the link I posed earlier.

I know that Ch 5A Wollongong had an early NEC high-level-modulated transmitter that required NO changes for colour. Where I lived we'd often watch that in preference to ABN 2 because the image was noticeably cleaner, ABN 2 always suffered from overshoot - group delay issues.

Re the other questions, it depends. Some later solid state analog transmitters can go digital, apparently.

Yes, the sound and vision transmitters were separate, combined into the antenna.

That video covers all this. The first NEC Tx shown (about 1980 vintage) had SS sound and a single tube for the vision.

_________________
Wax, paper, bitumen, cotton, high voltages - what could possibly go wrong?


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 4:09 pm 
Member

Joined: Nov Sun 11, 2018 12:32 am
Posts: 40
Probably a silly question, but...could one of these old transmitters do an ATSC or DVB signal as well?


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 4:11 pm 
Member

Joined: Nov Sun 11, 2018 12:32 am
Posts: 40
irob2345 wrote:
It's worth watching all the way through if you can put up with the boy-scout style of the commentator!



Ugh. I just cannot with this guy's voice. I've tried because he has a lot of interesting stuff on his channel but it's like nails on a chalkboard.


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sat 28, 2020 4:16 pm 
Member

Joined: Apr Sun 15, 2012 3:10 pm
Posts: 1053
Location: Buffalo, NY
Who in their right mind would ever wanna pay the electric bill for one of these relics?


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sun 29, 2020 12:13 am 
Member

Joined: Mar Mon 31, 2014 3:09 pm
Posts: 153
Re: B&W transmitters passing color signals
As a speech/broadcasting major at Miami University in 1967, I had a job running the board shift of our TV station, WMUB Ch.14.
In November of that year, the Public Broadcasting Laboratory program began, the forerunner of what would become PBS. Prior to that time, the National Educational Television stations "bicycled" videotape and film prints from station to station via mail or UPS. But PBL was to be the first nationwide, live origination --and in color. Since we were located in tiny Oxford, Ohio, we didn't have a line or microwave connection to broadcast that first show, but we did have an agreement with WCET in Cincinnati to re-transmit their signal. They were all set to go color, but WMUB-TV was still black and white throughout. Surprise, surprise, the next day the station manager said we were in color! We added a consumer color TV to the transmitter room, that was pressed into service by students like me to watch Laugh-In when it was on... Our transmitter was an RCA "New Line" rig, probably a TTU-30.


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sun 29, 2020 1:23 am 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 13667
Location: San Jose, CA USA
When I lived in Switzerland 2002-2003, I had the privilege to join the local radio club and tour the Swiss medium wave radio transmitting site at Beromuenster. In a large building there, many antique radio/TV items were stored, including an RCA TV transmitter, complete. It had been the first TV transmitter used in Switzerland, but was no longer in service. I suspect that transmitter is still there, and the members of the Swiss radio club CRGS probably know the details. Here are a couple of pictures I took then:

Attachment:
RCA TV Transmitter #1.png
RCA TV Transmitter #1.png [ 819.17 KiB | Viewed 1101 times ]

Attachment:
RCA TV Transmitter #2.png
RCA TV Transmitter #2.png [ 666.43 KiB | Viewed 1101 times ]

_________________
Tom K6VL


Top
 Profile  
 
 Post subject: Re: First generation TV transmitters
PostPosted: Mar Sun 29, 2020 1:38 am 
Member

Joined: May Sun 07, 2017 11:35 am
Posts: 840
Location: Belrose, NSW, Australia
Quote:
Who in their right mind would ever wanna pay the electric bill for one of these relics?


Well yes. The Mowbray Road site I mentioned earlier has an electricity substation on one side and a water reservoir on the other. Particularly in the analog days, with 5 TV networks and I don't know how many FM stations broadcasting from there, they must have sucked some power. At least the mains regulation would have been good and the supply reliable given the substation was / is supplied by underground cables.

_________________
Wax, paper, bitumen, cotton, high voltages - what could possibly go wrong?


Top
 Profile  
 
Post New Topic Post Reply  [ 55 posts ]  Moderators: 7jp4-guy, Mr. Detrola Go to page 1, 2, 3  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: No registered users and 9 guests



Search for:
Jump to:  


































-->


Privacy Policy :: Powered by phpBB