Why did CATV standarize in 75 ohms and everyone else in 50? The Next CEO of Stack OverflowHow is transmission line impedance selected?Industry standard Cat5e cablingWhy Characteristic Impedance must be 50 ohms?Why Inductor reactance 180 ohms?Why do cables have multiple grounds?Where did Bootstrapping get its name?What does S stand for in 75 S ohms?How did wireless telegraphy reach so far?What frequency did wireless telegraphs operate at?Problem understanding CDMA and W-CDMAStandard 2.54/1.27mm pinheader impedance
Salesforce opportunity stages
MT "will strike" & LXX "will watch carefully" (Gen 3:15)?
How to show a landlord what we have in savings?
How to coordinate airplane tickets?
What is the difference between 'contrib' and 'non-free' packages repositories?
Direct Implications Between USA and UK in Event of No-Deal Brexit
Planeswalker Ability and Death Timing
Does int main() need a declaration on C++?
pgfplots: How to draw a tangent graph below two others?
How can I replace x-axis labels with pre-determined symbols?
Car headlights in a world without electricity
A hang glider, sudden unexpected lift to 25,000 feet altitude, what could do this?
What did the word "leisure" mean in late 18th Century usage?
How do I secure a TV wall mount?
Why was Sir Cadogan fired?
Why did the Drakh emissary look so blurred in S04:E11 "Lines of Communication"?
Is it OK to decorate a log book cover?
Is this a new Fibonacci Identity?
What happens if you break a law in another country outside of that country?
How can a day be of 24 hours?
Does the Idaho Potato Commission associate potato skins with healthy eating?
What steps are necessary to read a Modern SSD in Medieval Europe?
Can you teleport closer to a creature you are Frightened of?
Read/write a pipe-delimited file line by line with some simple text manipulation
Why did CATV standarize in 75 ohms and everyone else in 50?
The Next CEO of Stack OverflowHow is transmission line impedance selected?Industry standard Cat5e cablingWhy Characteristic Impedance must be 50 ohms?Why Inductor reactance 180 ohms?Why do cables have multiple grounds?Where did Bootstrapping get its name?What does S stand for in 75 S ohms?How did wireless telegraphy reach so far?What frequency did wireless telegraphs operate at?Problem understanding CDMA and W-CDMAStandard 2.54/1.27mm pinheader impedance
$begingroup$
All of the CATV industry runs on 75 ohm systems, while most of the rest of the radio world uses 50 ohms.
Why was this standard chosen?
I was wondering this because good quality RG6 cable can be obtained everywhere for very little, compared to decent quality 50 ohm cabling.
impedance cables telecommunications coaxial
$endgroup$
|
show 1 more comment
$begingroup$
All of the CATV industry runs on 75 ohm systems, while most of the rest of the radio world uses 50 ohms.
Why was this standard chosen?
I was wondering this because good quality RG6 cable can be obtained everywhere for very little, compared to decent quality 50 ohm cabling.
impedance cables telecommunications coaxial
$endgroup$
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
1
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
1
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago
|
show 1 more comment
$begingroup$
All of the CATV industry runs on 75 ohm systems, while most of the rest of the radio world uses 50 ohms.
Why was this standard chosen?
I was wondering this because good quality RG6 cable can be obtained everywhere for very little, compared to decent quality 50 ohm cabling.
impedance cables telecommunications coaxial
$endgroup$
All of the CATV industry runs on 75 ohm systems, while most of the rest of the radio world uses 50 ohms.
Why was this standard chosen?
I was wondering this because good quality RG6 cable can be obtained everywhere for very little, compared to decent quality 50 ohm cabling.
impedance cables telecommunications coaxial
impedance cables telecommunications coaxial
asked 2 days ago
hjfhjf
4972823
4972823
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
1
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
1
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago
|
show 1 more comment
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
1
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
1
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
1
1
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
1
1
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago
|
show 1 more comment
1 Answer
1
active
oldest
votes
$begingroup$
How is transmission line impedance selected? explains why transmission line impedance matters.
The CATV industry deals with low-level signals, so it cares ONLY about loss and not at all about power-handling. That's why they chose 75Ω transmission lines.
$endgroup$
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
add a comment |
StackExchange.ifUsing("editor", function ()
return StackExchange.using("mathjaxEditing", function ()
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["\$", "\$"]]);
);
);
, "mathjax-editing");
StackExchange.ifUsing("editor", function ()
return StackExchange.using("schematics", function ()
StackExchange.schematics.init();
);
, "cicuitlab");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "135"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f429843%2fwhy-did-catv-standarize-in-75-ohms-and-everyone-else-in-50%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
How is transmission line impedance selected? explains why transmission line impedance matters.
The CATV industry deals with low-level signals, so it cares ONLY about loss and not at all about power-handling. That's why they chose 75Ω transmission lines.
$endgroup$
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
add a comment |
$begingroup$
How is transmission line impedance selected? explains why transmission line impedance matters.
The CATV industry deals with low-level signals, so it cares ONLY about loss and not at all about power-handling. That's why they chose 75Ω transmission lines.
$endgroup$
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
add a comment |
$begingroup$
How is transmission line impedance selected? explains why transmission line impedance matters.
The CATV industry deals with low-level signals, so it cares ONLY about loss and not at all about power-handling. That's why they chose 75Ω transmission lines.
$endgroup$
How is transmission line impedance selected? explains why transmission line impedance matters.
The CATV industry deals with low-level signals, so it cares ONLY about loss and not at all about power-handling. That's why they chose 75Ω transmission lines.
answered 2 days ago
Dave Tweed♦Dave Tweed
123k9152265
123k9152265
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
add a comment |
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
$begingroup$
Awesome! I didn't know that thing about power, and now I also understand why NOAA reception turnstile antennas specify 75 ohms too!
$endgroup$
– hjf
2 days ago
add a comment |
Thanks for contributing an answer to Electrical Engineering Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f429843%2fwhy-did-catv-standarize-in-75-ohms-and-everyone-else-in-50%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Some insight is in Andy's answer:electronics.stackexchange.com/questions/350451/…
$endgroup$
– glen_geek
2 days ago
1
$begingroup$
I'm not sure if I should say "a substantial minority" or "enough so that it's known" -- but there are radio amateurs who use 75 ohm transmission line for this reason. If you're going to run an antenna tuner anyway, and if you're going to build your own antennas anyway, then it's not a bad way to get a bit more bang for the buck.
$endgroup$
– TimWescott
2 days ago
$begingroup$
@TimWescott specifically, this: qsl.net/g4hbt/dipole.htm antenna specifies a 75 ohm line. I finally understand why.
$endgroup$
– hjf
2 days ago
1
$begingroup$
It was 75 ohms for RF signals before cable TV was a "thing". I've always figured it was the cable manufacturers, so they could force you to buy two spools of cable instead of just one. And the connector manufacturers, so they could sell you two different sizes of connectors.
$endgroup$
– Hot Licks
2 days ago
$begingroup$
The PAL TV standard was already 75 ohms for decades before cable TV.
$endgroup$
– user207421
2 days ago