FAQ
TL;DR: To extend a satellite run by 1.5 m, you need 3 pieces (two F-connectors + one “barrel”)—and “We do not use tees in antenna installations.” [Elektroda, jdubowski, post #16638928]
Why it matters:** This quick DIY prevents signal loss and avoids mistakes like joining two coax feeds.
For: homeowners/renters moving a TV ~1–2 m, unsure which wall cables are satellite and what parts to buy.
Quick Facts
- Extend one coax with: 2× F-connectors + 1× F–F coupler (“barrel”). [Elektroda, jdubowski, post #16638928]
- Never use a tee/splitter to combine two satellite coax lines. [Elektroda, jdubowski, post #16638928]
- If two similar coax cables exit the wall, test one at a time; don’t tie them together. [Elektroda, goldi74, post #16640763]
- Cables with many tiny colored wires are low‑voltage network/phone, not the satellite coax. [Elektroda, Ture11, post #16638786]
- A “satellite antenna under the roof” claim is unreliable; dish signals don’t run from an attic. [Elektroda, jdubowski, post #16641242]
How do I extend a satellite coax by about 1.5 meters?
Crimp or screw an F-connector onto the existing coax and another onto your 1.5 m lead. Join them using a female–female F “barrel.” Add a third F-connector at the decoder end if needed. That’s three pieces total. [Elektroda, jdubowski, post #16638928]
Which of the two wall coax cables should I use?
Pick one, fit the connector, and test the decoder. If it fails, try the other. Do not join the two together; results are unpredictable. “Extend one of them and see if it works.” [Elektroda, goldi74, post #16640763]
Can I use a tee/splitter to merge two coax cables into one TV input?
No. Tees are not used in antenna installations and can kill signal quality. As one expert put it, “We do not use tees in antenna installations.” Use only a straight F–F barrel to extend a single run. [Elektroda, jdubowski, post #16638928]
What connectors and couplers should I ask for in the store?
Ask for two F-connectors (often called “F-type ends,” “efka”) and one F–F barrel coupler. Most home-improvement or electronics stores carry these in the satellite TV section. [Elektroda, rafcio_21, post #16638788]
How do I correctly fit an F-connector? (3-step quick guide)
- Strip the coax to expose the center conductor and fold braid back.
- Slide on the F-connector until the dielectric is flush.
- Tighten or compress and then screw onto the barrel firmly.
Use the same method on both ends. [Elektroda, LeDy, post #16639351]
Are the other wall cables for Ethernet or phone lines?
Yes. The bundles with many tiny, colored wires are low‑voltage network or telephone leads, not satellite coax. Do not attach F-connectors to them. They terminate at switches, routers, or phone blocks in other rooms. [Elektroda, Ture11, post #16638786]
Is a satellite dish ever installed “under the roof” (in the attic)?
No. That phrase often confuses terrestrial TV with satellite. A dish needs clear sky, not an attic. If someone claims the dish is inside, recheck—attic antennas are for analog/DVB‑T, not satellite. [Elektroda, jdubowski, post #16641242]
Should I install a wall socket before extending?
It’s a good idea. Locate the other ends, label or 'call' them out, and fit a proper wall socket. Then run your short patch to the TV. This keeps things tidy and serviceable. [Elektroda, Radiokiller, post #16640905]
How do I identify the correct cable end in another room?
Find the other terminations and 'call' or tone them to confirm continuity. Once identified, label the run and proceed with the extension using the barrel method. [Elektroda, Radiokiller, post #16640905]
Do I need to know if my receiver is DVB‑T or satellite before extending?
Yes. Verify whether your device is a DVB‑T terrestrial receiver or a satellite decoder. Extend only the matching coax line from the proper antenna or dish, then test. [Elektroda, rafcio_21, post #16640778]
What if both coax cables are from the dish (twin feed)?
Treat them as separate feeds. Use only one for a single‑tuner decoder. Do not combine them. If one doesn’t work, test the other as a separate run. [Elektroda, goldi74, post #16640763]
Will a 1.5 m extension hurt signal quality?
A short 1.5 m patch is fine when joined with F-connectors and a barrel. Keep connections snug and avoid tees to prevent losses. The original thread involved exactly a 1.5 m need. [Elektroda, Dukerss, post #16638894]
Any proof this approach works in practice?
Yes. The original poster confirmed success after a knowledgeable friend extended the cable cleanly using the described approach. [Elektroda, Dukerss, post #16641520]
What’s the failure mode if I join the two coax cables together?
Joining two separate feeds can cause shorting between LNB control voltages and 22 kHz tones, resulting in no reception. Avoid combining; test one line at a time. [Elektroda, goldi74, post #16640763]
