Hi,
Nearly right, but its for matching coax 75 ohm to a twin lead 300 ohm input.
Certainly useless for TV's, which are all 75 ohm, perhaps some old radio use.
rgds, sreten.
All new TVs, yes.
But these baluns probably saw their most widespread use in the 1980s, to connect cable TV to older TV sets.
And they are bi-directional, so still useful to connect an antenna to a new TV for over-the-air broadcasts.
But these baluns probably saw their most widespread use in the 1980s, to connect cable TV to older TV sets.
And they are bi-directional, so still useful to connect an antenna to a new TV for over-the-air broadcasts.
I didn't know that. Maybe it was a USA thing? Certainly not uncommon here, in the days of RF modulators for game consoles and TV computer monitors. Most TVs had only twin-lead inputs.
It's always good to spread smiles.
52
So the whippersnappers can think of cable TV as something that "just is," whereas I can remember the first time I saw it. The only home in the neighborhood with it, because the dad worked for the cable company. My father had a similar memory for TV itself. He grew up during radio's heyday.
Your time is coming.🙂
52
So the whippersnappers can think of cable TV as something that "just is," whereas I can remember the first time I saw it. The only home in the neighborhood with it, because the dad worked for the cable company. My father had a similar memory for TV itself. He grew up during radio's heyday.
Your time is coming.🙂
I'm with young spud here. Time was I never saw a TV without twin-lead antenna connectors, and those baluns (balanced to unbalanced transformer) were on the back of every cable-connected TV.
Age fourtysomething here. I had a friend who had an antenna rotator on the family TV. Antenna rotator was on an antenna up on a pole outside.
I just happened across a rotator in my piles of stuff.
I just happened across a rotator in my piles of stuff.
Used quite a few of these in my youth. Needed them to hook gaming systems (nintendeo, sega, etc) up to our thrift store TVs.
I remember vividly that they all had the two leads because I would always break the crimped on spades and then have to carefully peal off the insulation to make it useable again. Those wires were really thin.
I remember vividly that they all had the two leads because I would always break the crimped on spades and then have to carefully peal off the insulation to make it useable again. Those wires were really thin.
😀 You can always count on sreten for a useless and contradicting comment.🙄
Also the "useless for TV's, which are all 75 ohm" bit.
OF COURSE you need such a balun, TODAY (and ALWAYS) to adapt a typical dipole antenna 300 ohms impedance to 75 ohms, whether it's a coax cable feed line or a humble pair of rabbit ears on top of the TV .
Looks like Sreten only knows Cable TV and ignores that there is also air transmission ....... which involves ....... uh ...... "antennas" on both ends.
Makes me remember the 4 y.o. kid at the Supermarket who thought that milk grew in bottles and sachets, and meat grew in trays, already cut.
Well, not bad for a 4 y.o. 😛
I agree, and would like to add that, at its inception, over the air broadcast was the only way to watch TV. Cable TV became available more than two decades later.
It is also easier and cheaper to manufacture a parallel 300 ohm cable and, also important, it suffers much less attenuation over a given run length than coaxial cable.
With some gents in the building business here, it's still popular to DIY their own construction radios, used to be the standard.
Require a balun to hook up the car radio to a regular antenna cable.
(counted my molars, I'm still under 70, I think)
Require a balun to hook up the car radio to a regular antenna cable.
(counted my molars, I'm still under 70, I think)
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You mean someone has a junkbox that's missing the OP baluns and the reverse, with two screws and a F-type quick-connector?🙂
Hi,
Thanks for your utterly moronic comments. It seems 300 ohm
feed for TV's was common in North America, not in the UK,
where it generally only applies to FM radio reception.
And most FM tuners I've seen have dual 300/75 inputs,
but I can't vouch for older stuff, maybe 300 ohm only.
Like I said I've never ever seen a 300 ohm feed TV.
And moronically your claiming its a 300 ohm to 75 ohm adaptor,
which it isn't, its a 75 ohm to 300 ohm adaptor, which is pretty
useless in the UK, and I quite accept that in NA the history of
TV and the consequences of the much earlier introduction of
cable I'm somewhat ignorant, but the cable stuff makes sense.
rgds, sreten.
iTs called a "Balun" as in balanced to unbalanced, 4:1 in this case
300 ohm twin lead (balanced) to 75 ohm Coax cable (unbalanced)
it's a ferrite transformer. As with any transformer its Bi-directional
some have simple tuning/loading elements (not this one).
if you don't recognize it Sreten move along to another thread... nobody cares
300 ohm twin lead (balanced) to 75 ohm Coax cable (unbalanced)
it's a ferrite transformer. As with any transformer its Bi-directional
some have simple tuning/loading elements (not this one).
and utterly starting off a conversation to a reasonable poster by calling him an unflattering name (twice sometimes in the same post) for no reason in sight.You can always count on sreten for a useless and contradicting comment.
if you don't recognize it Sreten move along to another thread... nobody cares
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As I said, it's bidirectional. It's both 75:300 and 300:75. They make the two different kinds just for ease of connection.
I suppose in the UK and elsewhere they were always at the antenna end. Some are sold fitted with rubber boots for outdoor apps.
I suppose in the UK and elsewhere they were always at the antenna end. Some are sold fitted with rubber boots for outdoor apps.
In Australia too, colour even (mid '70s when PAL was implemented)
I used to use a folded dipole when my parents wouldn't let me drill holes in their walls 😀
Maybe Sreten is a little younger than I assumed. (I'm forty something 😉)
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