Ham Radio Coax, Connectors & Adapters: What to Use (2026)
For long 2 m/70 cm runs, use genuine LMR-400. Choose RG-213 for rugged HF/general station use, and RG-8X when flexibility and a shorter run matter more.
Quick picks
Genuine Times Microwave LMR-400
The cable I’d spend money on when a long 2 m or 70 cm feedline is otherwise throwing away useful signal.
- Only about 1.5 dB/100 ft at 150 MHz in Times Microwave’s published data
- About 2.7 dB/100 ft at 450 MHz
- Limitation: thick and relatively stiff — poor choice for a short flexible jumper
Amphenol RG-213/U
A traditional thick copper-braid workhorse when durability, high-power HF use and familiar PL-259 connections matter.
- Stranded copper center conductor with heavy copper-braid shielding
- Excellent HF station cable and reasonable for shorter VHF runs
- Limitation: more loss than LMR-400 when VHF/UHF runs become long
RG-8X
Lighter and easier to route than the thick cables above, making it useful for HF, portable stations and short patch leads.
- Much easier to route and coil than 0.405-inch feedline
- Good fit for HF and shorter runs
- Limitation: loss rises quickly enough that I would not use a long RG-8X run for 70 cm
Which coax should you use?
Swipe → to see the full comparison
| Cable | Best for | Flexibility | HF | 2 m | 70 cm | Check |
|---|---|---|---|---|---|---|
| LMR-400 | Long VHF/UHF feedlines | Fair | Excellent | Excellent | Best of these three | Current price → |
| RG-213 | HF / rugged station runs | Good | Excellent | Good | Shorter runs | Current price → |
| RG-8X | Portable / short flexible runs | Very good | Very good | Short runs | Avoid long runs | Current price → |
Why cable loss matters much more on VHF and UHF
Feedline loss rises as frequency rises. That is why a cable that works perfectly well on 40 meters can become a poor choice for a long 70 cm run.
If you want to calculate your exact run rather than rely on general categories, use the Times Microwave coax loss calculator .
The coax choices in detail
1. Genuine Times Microwave LMR-400
If the antenna is on a mast and the radio is fifty or a hundred feet away, this is the situation where spending extra on feedline makes sense. At VHF and especially UHF, cable loss can consume a meaningful portion of both your transmitted signal and the weak signal arriving from the antenna.
Genuine LMR-400 is a 50-ohm, approximately 0.405-inch cable designed specifically as a low-loss communications feedline. Times Microwave publishes 1.5 dB/100 ft at 150 MHz and 2.7 dB/100 ft at 450 MHz. That is why I would prioritize it for a permanent 2 m/70 cm installation before spending the same money chasing a few more watts from the radio.
The Amazon assembly below is made using genuine Times Microwave LMR-400 rather than a similarly named generic “400” cable. That distinction matters because not every cable with “400” in its title has the same construction or published attenuation.
There are two useful connector routes. If your radio and antenna use ordinary UHF connectors, the PL-259 assembly is the simplest. If your antenna, lightning protector or other equipment already uses Type N — particularly on 70 cm — I would choose the Type N assembly rather than adding unnecessary adapters.
The downside is mechanical. Standard LMR-400 is thick and relatively stiff. I do not like hanging a long piece of it directly from a small analyzer, handheld or SMA connector. Use a short flexible jumper at the equipment when strain relief is needed.
Best for: permanent VHF/UHF base antennas and longer feedline runs where attenuation matters.
Skip it if: you need a short cable that will constantly move, coil or flex behind portable equipment.
2. Amphenol RG-213/U
RG-213 is an old-fashioned choice in the best sense of the word: thick copper, a stranded center conductor, heavy braid and no attempt to pretend that it is a tiny lightweight cable.
For HF work, that makes it a very sensible station feedline. Loss is relatively modest at HF frequencies, the cable is mechanically robust and it is well suited to the familiar PL-259/SO-239 ecosystem found on HF radios, tuners, switches and many antennas.
The Amphenol assembly I linked uses a 96% bare-copper braid and preinstalled PL-259 connectors, removing connector installation from the first-time buyer’s job list. That matters because even very good coax can be ruined by a badly installed connector.
RG-213 is also perfectly usable on VHF when the run is sensible. The reason I would move to LMR-400 is not that RG-213 suddenly stops working at 2 m or 70 cm; it is that its attenuation becomes increasingly expensive as frequency and cable length increase.
Best for: HF base stations, high-power use and rugged installations where a traditional copper-braid cable is desirable.
Skip it if: you are installing a long 70 cm feedline and can justify lower-loss cable.
3. RG-8X
RG-8X fills the gap between very thin RG-58 and the much thicker full-size cables. It is easier to route through a portable station, behind equipment or around a vehicle, and it coils more conveniently when the station has to be packed away.
That makes it a very useful HF cable and a sensible choice for short jumpers between a radio, tuner, switch, dummy load or SWR meter. Its flexibility is a feature, not an apology.
Where people get into trouble is assuming that because RG-8X is good at HF, a hundred feet of it must also be a good 70 cm feedline. It isn’t the cable I would choose for that job. Frequency and length together determine whether the convenience is worth the loss.
Also note that RG-8X and LMR-240-sized low-loss cables may have similar outside diameters, but the names are not interchangeable specifications. Always use the actual manufacturer’s attenuation data rather than assuming two similarly sized cables perform identically.
Best for: HF, portable stations, short equipment jumpers and installations where flexibility is more valuable than minimum possible attenuation.
Skip it if: your antenna is fifty or a hundred feet away and you primarily operate 2 m or 70 cm.
What about RG-58?
RG-58 is not useless. It is small, inexpensive and flexible, which makes it perfectly reasonable for very short patch leads and some mobile or low-power applications.
What I would not do is install a long RG-58 run to a VHF/UHF base antenna. A current Belden RG-58 specification rises from roughly 3.8 dB/100 ft at 100 MHz to 7.9 dB/100 ft at 400 MHz.
Use thin coax where being thin is useful. Do not choose it simply because it is the cheapest cable that reaches the antenna.
PL-259 vs Type N vs BNC vs SMA
PL-259 / SO-239
The familiar ham-radio connector. PL-259 is the male plug; SO-239 is the matching female jack.
It is rugged, inexpensive and extremely common on HF radios, tuners, meters and many VHF antennas.
The important limitation is electrical: the traditional UHF connector is not a constant-impedance precision interface. Standard designs are generally specified around the lower RF range rather than microwave use.
Type N
Type N is a 50-ohm threaded RF connector designed for much higher frequency performance and outdoor use.
If both ends of a 70 cm or higher-frequency installation already support Type N, it is the connector I would prefer.
Do not add two adapters to an existing SO-239 installation solely because Type N is theoretically better. Use the best connector that fits the equipment without creating unnecessary transitions.
BNC
BNC uses a quick bayonet connection and is common on test equipment, scanners and some portable equipment.
Make sure you are using a 50-ohm BNC part for a normal 50-ohm amateur radio system rather than assuming every physically compatible BNC connector has the same impedance.
SMA
SMA is common on handheld radios, small analyzers, SDR equipment and RF accessories.
Do not hang thick LMR-400 from a tiny SMA connector and let the cable act as a lever. Use a short flexible pigtail or jumper when mechanical strain would otherwise be transferred to the equipment.
Are coax adapters bad?
A good adapter is not something to fear. Sometimes the radio has SO-239, the antenna system uses Type N and an adapter is the sensible way to join the two.
The mistake is building an adapter tower: PL-259 to BNC, BNC to SMA, SMA back to another connector, all hanging from the radio. Every extra junction is another mechanical connection, another place for moisture or corrosion, and another thing to troubleshoot later.
Whenever possible, buy a cable assembly with the correct connector on each end rather than buying the wrong cable and solving it with several adapters.
Every outdoor coax connection needs a weather plan
Water inside coax is one of those station failures that can remain hidden for a long time. The radio still works, the SWR may not look catastrophic, but feedline loss increases and performance slowly gets worse.
Use cable designed for the environment, seal outdoor connector junctions correctly and leave a sensible drip loop where appropriate. For underground installations, choose a cable specifically designed for direct burial rather than assuming an ordinary outdoor jacket is enough.
Times Microwave sells separate water-blocked/direct-burial versions of its LMR cables for exactly this reason.
Check Current Price on Amazon — Coax-Seal → Amazon affiliate linkHow to choose coax for your ham radio station
1. Start with frequency and length
Those two numbers matter more than the marketing name printed on the cable. A twenty-foot HF run is a very different engineering problem from a hundred-foot 70 cm feedline.
At HF, ordinary quality 50-ohm coax can have acceptably low loss over practical station distances. As frequency rises through 6 m, 2 m and 70 cm, the difference between cable types becomes much more important.
2. Use the shortest sensible run
Buying lower-loss coax and then adding forty unnecessary feet defeats the purpose. Route the cable safely and leave enough service slack, but do not buy extra length simply because a 100-foot assembly is only slightly more expensive than the 50-foot version.
3. Do not choose by cable diameter alone
Two cables with similar outside diameters can use different conductor, dielectric and shielding constructions and therefore have very different attenuation.
This is also why I would not treat every cable sold as “LMR-400 equivalent” as though it automatically has Times Microwave’s published LMR-400 performance. Look for an actual loss specification from the manufacturer.
4. Choose flexibility where movement is expected
Standard low-loss solid-center cables are excellent permanent feedlines but are not automatically the best choice for a portable station or a section that will repeatedly bend.
Use a flexible or UltraFlex-style version where movement is expected. This is especially useful between rigid feedline and small radio/test equipment connectors.
5. Match the connector to the band and equipment
PL-259 is perfectly normal for an HF station and remains common on 2 m equipment. On 70 cm and higher, Type N becomes increasingly attractive when the antenna, arrester and other equipment already support it.
Connector performance matters, but changing connector families is not valuable if doing so requires a chain of adapters at both ends.
6. Pre-made cable assemblies make sense for most beginners
Installing coax connectors correctly is a useful skill, but the first station does not need to become a soldering project. A professionally terminated assembly eliminates one common failure point.
If you install your own connectors, test center-to-center continuity, shield-to-shield continuity and confirm there is no center-to-shield short before connecting the cable to the radio.
7. A good SWR reading does not prove the feedline is good
Lossy coax can actually make the SWR measured at the radio end look better because reflected energy is being lost in the cable on the way back. That is not an antenna improvement — it is wasted RF.
Our SWR meter and antenna analyzer guide explains how to test the antenna system properly.
What to avoid
Do not buy coax by price per foot alone.
A cheap hundred-foot feedline can cost you more signal than upgrading the radio would ever recover. Check the manufacturer’s attenuation at the highest frequency you plan to use.
I would also avoid long RG-58 or RG-8X runs on 70 cm, adapter chains hanging from small connectors, outdoor joints with no weather protection, and generic “400” coax whose actual attenuation is never specified.
Finally, never run ordinary coax directly through a location where electrical, lightning or building-code requirements call for proper grounding, bonding or entrance protection. See our grounding and lightning guide before building a permanent outdoor station.
Where coax fits into the rest of your station
VHF/UHF base antenna
Antenna height and feedline loss work together. Choose both before putting the mast up.
VHF/UHF base antennas →Mobile ham radio
Vehicle installations need the right radio, antenna, coax and safe cable routing.
Best mobile ham radios →SWR meter & analyzer
Test the antenna system and understand what the reading is actually telling you.
SWR meters & analyzers →First HF antenna
Choose the antenna before deciding how much feedline and which connector arrangement you need.
Your first HF antenna →HF base station
Plan the entire permanent HF station rather than treating coax as an afterthought.
HF base stations →Grounding & lightning
Outdoor feedlines need an entrance, bonding and lightning-protection plan.
Grounding & lightning protection →Portable operating
Portable stations often benefit more from lightweight flexible coax than the absolute lowest-loss cable.
Portable operating gear →Antenna tuner
Understand what the tuner changes — and what losses remain in the feedline.
Antenna tuners →Building your first station?
See where coax belongs in the complete buying order.
Your first ham station →Ham radio coax FAQ
What is the best coax for a 2 meter ham radio?
For a short run, several quality 50-ohm cables can work well. As the run approaches 50–100 ft, I prefer lower-loss cable such as LMR-400 because attenuation at VHF becomes significant.
What is the best coax for 70 cm?
Use genuinely low-loss 50-ohm feedline, particularly when the run is long. LMR-400 is the starting point I recommend on this page. If the antenna and other equipment already provide Type N connectors, I would also prefer Type N over traditional PL-259 for the UHF side.
Is RG-8X good for ham radio?
Yes. RG-8X is very useful for HF, portable stations and shorter flexible connections. What it is not is my first choice for a long 70 cm feedline, where lower attenuation matters much more.
Is RG-58 okay for ham radio?
Yes for the jobs that suit it: short patch leads and installations where thin flexible cable is useful. I would avoid a long RG-58 run to a VHF/UHF base antenna because the loss rises substantially with frequency.
Is LMR-400 better than RG-213?
For long VHF/UHF feedlines, LMR-400’s lower attenuation makes it the better choice here. RG-213 remains an excellent rugged HF/general station cable with a stranded copper center conductor and traditional copper-braid construction.
Should I use PL-259 or Type N connectors?
Use the connector system that makes sense for the equipment and frequency. PL-259 is extremely common for HF and VHF amateur equipment. Type N is the better high-frequency/weather-resistant interface when your 70 cm or higher-frequency equipment already supports it.
Do outdoor coax connectors need weatherproofing?
Yes. Build every outdoor connection with moisture protection in mind, even when using connectors designed for outdoor RF work. Use an appropriate sealing system and cable rated for the environment.
Can I bury ordinary LMR-400?
Do not assume that an outdoor-rated cable is automatically intended for direct burial. Times Microwave makes dedicated water-blocked LMR-400-DB for direct-burial applications. Match the cable construction to the installation environment.
Useful coax and connector resources
- ARRL — Feed Lines — introduction to selecting transmission line and understanding loss.
- Times Microwave Coax Loss Calculator — calculate loss for a specific cable length and frequency.
- Times Microwave — LMR-400 — official construction and application information.
- Amphenol RF — UHF / PL-259 connectors
- Amphenol RF — Type N connectors
- ARRL — Installing Coax Crimp Connectors — useful if you decide to terminate your own feedline.
Safety note: Permanent outdoor antenna systems can require grounding, bonding, lightning protection and code-compliant building entry methods. Follow applicable electrical/building requirements and qualified professional guidance where necessary. Wholly Outdoor is not affiliated with the FCC, NCVEC, ARRL, Times Microwave or Amphenol.