ECN Forum
Posted By: Trumpy TV Connectors? - 01/19/03 03:34 AM
I think I may have touched on this subject,
before, but what type of connector for TV and
Cable(if available), is used in your country?.
We are only just starting to move away from the older Belling-Lee style arrangement, in favour of the newer F-type connector.
All of our splitter equipment is now F-type, it makes sense to change and they never come loose either.
Your thoughts on this-
Posted By: SvenNYC Re: TV Connectors? - 01/19/03 05:56 AM
F-Plug here in NTSC land.

BNC connectors are used for video-security systems and some pro video setups (because it's faster to hook up but still just as secure).

There are two types of F-plugs. Push-on and screw-on. I prefer screw-on.

Some TV sets use screw-terminals with spade lugs on twin-lead set-top "rabbit ear aerials".

I recently saw a stereo in a hi-fi store that used a PAL antenna jack for the FM antenna (looks almost like an F-plug but the center pin is hollow or something), which I thought was weird. Maybe the manufacturer got a good deal on them?

Trumpy do you have a picture of the Belling-Lee plug you could post?
Posted By: pauluk Re: TV Connectors? - 01/19/03 12:40 PM
The Belling-Lee plug has been standard in the U.K. for just about as long as TV has been around. Our TVs have always been designed for 72 ohm coaxial -- The American-style 300-ohm twin feeder never caught on here.

Here's a Belling-Lee plug:
[Linked Image from members.aol.com]

And an in-line B-L socket:
[Linked Image from members.aol.com]

Sockets are also available to fit a standard single-gang wall box:
[Linked Image from members.aol.com]

The Belling-Lee plug is also found on FM broadcast receivers, although some of these (notably Japanese imports) also provide for 300-ohm twin lead.

When it comes to satellite and cable installations, the F-type plug has become the defacto standard.

For direct video and audio connections, domestic equipment often uses RCA jacks (called "phono sockets" here) for both, although older VCRs used BNC for video.

We also now have a big multi-way connector commonly referred to as a SCART plug:
[Linked Image from members.aol.com]
This is a common European connector found on practically all domestic TV/VCR equipment these days which provides direct RGB video, stereo audio connections etc. all on one plug. It supposedly makes it easy for the layman to interconnect equipment, but in practice there are often problems!

Much low-end new equipment now comes with no other direct video/audio connections other than a couple of SCART sockets.


[This message has been edited by pauluk (edited 01-19-2003).]
Posted By: Hutch Re: TV Connectors? - 01/19/03 04:52 PM
Belling-Lee - Never heard them called that before. In South Africa (which uses them) I referred to them as FM plugs and over here in the States they are known as PAL connectors. I have a couple of PAL to F-type adapters that I purchased at Radio Shack to connect my imported multi-system, multi-voltage TV and video system when I arrived here. Having worked with both types, my vote goes for the F-type connector. As Trumpy says, being screw-on they make for a more positive connection. Also, they are more easily wired up with the male ‘pin’ being formed from the coaxial core and the sheath being crimped on. The tiny screws and compression ring in the PAL connector were always, for me, a weak link in the chain, and a source of a poor signal.
Posted By: Texas_Ranger Re: TV Connectors? - 01/21/03 08:10 PM
Belling-Lee for 75 Ohm antenna, F for satellite. Any equipment from the 60ies or eralier used to have 2 single pin plugs with 4mm pins, commonly referred to as "banana plugs". They were used on virtually any electronics product back then (radio, reel-to-reel tape recorder, record player, TV,...). With audio equipment this was superceded by DIN connectors and later RCA jacks (some appliances still have DIN plugs, but they're very rare by now). NF was BNC with old stuff, nowadays Scart or RCA. Is Scart used in the US? I think it was originally called "Euro-Scart".
Posted By: SvenNYC Re: TV Connectors? - 01/21/03 08:37 PM
Quote
Is Scart used in the US? I think it was originally called "Euro-Scart."

No. As far as I know, SCART is not used in NTSC television sets.

I'm familiar with Bananna plugs. They're used on some multimeters and other test kit for electronics (radio/TV repair)

Aside from F-plugs for 75-ohm antenna connections, RCA (phono) jacks for line-level audio & video and BNC for security systems, we have something called S-Video (common in high-end video tape and disk equipment), which uses a tiny round multi-contact plug that is similar to a Mini-DIN, the type of plug used on modern-day computer mice and keyboards.

Here is a picture of an S-Video jack:
[Linked Image from evga.com]

[This message has been edited by SvenNYC (edited 01-21-2003).]
Posted By: pauluk Re: TV Connectors? - 01/21/03 09:46 PM
Yes, SCART is a European invention, although I think it has now spread to other parts of the world, North America excluded.

For further details: http://www.rgbtosvideo.com/tech/scartconnector.pdf

The S-video 4-pin connectors are found here now as well, although obviously in most cases they are carrying 625/PAL signals.

Standard banana plugs were also once very common on much equipment here, although for domestic radios etc. a smaller "split-pin" type of plug was used, commonly known as a "wander plug." They were often found as antenna and ground connections on 1950s radios.
Posted By: Trumpy Re: TV Connectors? - 01/22/03 05:38 AM
Paul,
Is that true about 300 ohm Ribbon?, I thought that us over here in NZ, took our first TV reciever systems, from the UK system?, which meant Huge low-band VHF aerials, and Ribbon cable.
Believe me, Paul, we are still taking out Ribbon from elderly peoples homes, who have just purchased a new digital TV set(for some reason, I've been told, these TV's are louder),and a hearing aid is not required to watch them.
But, with regards to F-connectors, I prefer the crimp type, especially for Outdoor connections, these have a special sealing grease in the rear part and a rubber O-ring in the front part of the plug, where the centre conductor protrudes, these are standard in all of my aerial installations. [Linked Image]
Posted By: Trumpy Re: TV Connectors? - 02/03/03 05:17 AM
Can anyone tell me what the maximum length of run, of a low-level signal cable is?.
I am talking about SCART leads and S-VHS leads.
Is there an amplifier that can be inserted,
mid-way, to maintain the signal levels, over a great length of run.
Your help please?.-
Posted By: pauluk Re: TV Connectors? - 02/06/03 12:26 AM
Sorry Trumpy, I missed your earlier question about the antenna feeders.

I can't say that 300-ohm twin lead was never used on very early sets here, but I've worked on vintage British TV sets dating right back to the late 1940s and I've never found anything other than the Belling-Lee coaxial type of connector.

On signal leads, the main limiting factor for video signals is the attenuation and phase shift of the higher frequency components of the signal. That's determined largely by a combination of the cable's capacitance and the impedance of the source, so the total allowable length can vary considerably.

It's certainly possible to insert amplifiers to maintain signals levels on long cable runs. The principle is used extensively on long-distance telephone trunks, undersea communication cables, etc.
Posted By: djk Re: TV Connectors? - 02/06/03 01:08 AM
I recall that we had a sony portable tv in Ireland with the clamp on spade type connections. I think it was to hook up to its own antenna though. I remember connecting it to a cable system in cork in the mid-1980s was an absolute nightmare as there was nothing except the standard co-ax PAL type connector. we managed to clamp the middle of the coax to one of the clamps and the sheilding to the other and it worked!

Ireland normally uses B-L plug for antennas UHF/VHF

Cable and satellite mostly use crimp-on F-Connectors to the back of the decoders/set top boxes.
almost always SCART to the TV/VCR
most higher spec tvs use RGB rather than PAL (composite) signals from the set top decoder.
Posted By: SvenNYC Re: TV Connectors? - 02/06/03 02:14 AM
Paul:

What about BNC connectors (that's redundant). What are they used for?

I always thought that the BNC plug would have been a more logical device for interconnecting TV aerials and equipment instead of the push-on Belling-Lee plug since it's much more secure.

P.S.: Why is the PAL plug called Belling-Lee? Was it invented by two guys named Belling & Lee?

I wonder if Bell wire is so called because it was first used by A.G. Bell or is it Bell wire because it's used for wiring electric doorbells (and sometimes single-pair phone line if you wanna be cheep and you're only getting one line service) [Linked Image]
Posted By: classicsat Re: TV Connectors? - 02/06/03 02:25 AM
BNC is used for professional video. My guess
is it is too expensive for consumer level video and RF, where RCA (AKA Cinch), BL and F connectors do.

I'd say bell wire is called so becuase of
doorbells.
Posted By: Texas_Ranger Re: TV Connectors? - 02/06/03 11:05 AM
Older video equipment made by "international" manufacturers like Panasonic (early 80ies) used to have BNC plugs for NF signals. My 1983 Panasonic VHS for example had them. European equipment used to have a round 6pin DIN plug, combined Video/Audio/In/Out (I know it from the Siemens/Grundig Video 2000 line). Mid- to late 80ies equipment already changed to Scart. My international (NTSC/PAL) 70ies Toshiba (?) TV has RCA jacks.
Posted By: pauluk Re: TV Connectors? - 02/07/03 11:59 PM
The loop antennas popular on some 1970s portables is about the only place you'll find spade antenna connections on British TV sets (or perhaps I should say sets made for the British market, as the majority were of Japanese origin). They were often arranged on a small paxolin board next to the B-L coaxial socket with a small balun.

Yes, bell-wire is so named for its most common application -- Doorbells.

BNC connectors were found on domestic VCRs here in the 1970s/early 1980s, but these days they're limited more to professional equipment. They've become the defacto standard connectors on a lot of test equipment, e.g. oscilloscopes, signal generators, frequency counters.

Sven,
Yes, the British coaxial socket took its name from the Belling-Lee company, which was formed as a partnership between a Mr. Belling and a Mr. Lee. Belling-Lee is based near to where I'm from originally, in north London.

Almost everyone in Britain will recognize the name Belling as being a big manufacturer of electric stoves, heaters, etc.


[This message has been edited by pauluk (edited 02-07-2003).]
Posted By: Trumpy Re: TV Connectors? - 02/08/03 02:43 AM
Paul,
Don't all RF connectors have a certain frequency bandwidth, where above this, the insertion loss becomes too high, especially with UHF signals?.
Mind you, there are N-Connectors, F-connectors, PL-259/SO-239 Connectors, Mini-UHF, BNC, TNC, etc, all have their own uses.
The BNC connector is also used these days in
Ethernet applications and LAN systems. [Linked Image]
Posted By: Texas_Ranger Re: TV Connectors? - 02/08/03 11:50 AM
Ethernet? Coax EThernet with BNC plugs died some 8 years ago here in Austria and was completely replaced by RJ45. Some ethernet hubs still come with 1 BNC connector for hooking up old machines though. The only such computer in our small macintosh network is a 1989 Mac IIci. All others have RJ45.
Posted By: pauluk Re: TV Connectors? - 02/08/03 01:05 PM
Yes, the construction of the various types of connector can limit the useful upper frequency limit.

You mentioned PL259/SO239 (for those not familiar with these designations, they're the type commonly used for antenna connections on CB and amateur radio equipment). These were also used as video connectors on some 1960s/early 1970s gear.
© ECN Electrical Forums