Amphenol AFA151-20 N Male Crimp Connector for LMR-400 and RG-8 Cable
The Amphenol AFA151-20 is a straight, 50 ohm Type N male (plug) connector for 400-size coaxial cable, including LMR®-400 and RG-8. It uses a soldered center pin, a crimped outer ferrule with a standard 0.429" hex crimp, and a no-braid-trim cable prep that removes a step from field termination. It is rated DC to 6 GHz with VSWR of 1.3:1 or better, sealed to IP67 with a silicone O-ring, and built to the IEC 61169-16 Type N interface standard.
Is the AFA151-20 the Right Connector for Your Job?
- Use it if: you are terminating LMR-400 or RG-8 size coax with an N male, you have a 0.429" hex crimp die, and you are comfortable soldering the center pin.
- Use it if: the connection is outdoors or exposed to weather (IP67 sealed, rated -40°C to +125°C).
- Choose something else if: you need a female (jack), right angle, or bulkhead connector, a different cable size, or a tool-less/compression style.
- Ask us first if: your cable is a stranded-center or specialty 400 variant (UltraFlex, DB, FR). Amphenol does not list these on the drawing.
Key Specifications
| Manufacturer | Amphenol (Amphenol Fuyang, Changzhou) |
| Part Number | AFA151-20 |
| Drawing Number | AFS-A151-20 (NM-400) |
| Interface | N Male (Plug), IEC 61169-16 |
| Body Style | Straight |
| Impedance | 50 Ohm |
| Frequency Range | DC to 6 GHz |
| Cable Type | LMR-400, RG-8 (400 size) |
| Center Contact Attachment | Solder |
| Outer Conductor Attachment | Crimp, 0.429" hex |
| Coupling Nut | 19 mm hex |
| Cable Prep | No braid trim |
| Ingress Protection | IP67 |
| Operating Temperature | -40°C to +125°C (-40°F to +257°F) |
| RoHS | Compliant |
Electrical Performance
| Nominal Impedance | 50 Ohm |
| Frequency Range | DC to 6 GHz |
| VSWR | ≤ 1.3:1 |
| Insertion Loss | ≤ 0.1 × √F(GHz) dB |
| Insulation Resistance | ≥ 5,000 MΩ |
| Proof (Dielectric Withstanding) Voltage | 2,500 Vrms |
| Contact Resistance, Center | < 1.0 mΩ |
| Contact Resistance, Outer | < 0.2 mΩ |
Maximum Insertion Loss by Band
Calculated from Amphenol's rated maximum of 0.1 × √F(GHz) dB. Real-world loss is typically lower.
| Band / Use | Frequency | Max Insertion Loss |
|---|---|---|
| VHF land mobile | 150 MHz | 0.04 dB |
| UHF land mobile | 450 MHz | 0.07 dB |
| 700/800 MHz public safety | 800 MHz | 0.09 dB |
| 900 MHz ISM / LMR | 900 MHz | 0.09 dB |
| 2.4 GHz WiFi / ISM | 2.4 GHz | 0.15 dB |
| 5.8 GHz WiFi / ISM | 5.8 GHz | 0.24 dB |
Mechanical Performance
| Mating Cycles | 500 |
| Coupling Nut Torque Rating | 3 N·m (approx. 26.5 in-lb) |
| Cable Retention Force | 400 N (approx. 90 lbf) |
| Torsion (Cable to Connector) | 2 N·m (approx. 17.7 in-lb) |
Materials and Plating
| Part | Material | Plating |
|---|---|---|
| Center contact (pin) | Brass | Gold, 1.3 µm |
| Outer conductor (body) | Brass | Copper-tin-zinc (tri-metal), 3 µm |
| Coupling nut | Brass | Copper-tin-zinc (tri-metal), 3 µm |
| Crimp ferrule | Copper | Copper-tin-zinc (tri-metal), 3 µm |
| Insulator | PTFE | N/A |
| Seal | Silicone rubber O-ring | N/A |
Environmental Ratings
| Temperature Range | -40°C to +125°C |
| Climatic Category | IEC 60068: 40/125/21 |
| Thermal Shock | IEC 60068-2-14 (Test Na) |
| Vibration | IEC 60068-2-6 (Test Fc) |
| Mechanical Shock | IEC 60068-2-27 |
| Waterproof Rating | IP67 |
| RoHS | Compliant |
What Does "No Braid Trim" Mean?
On many crimp connectors, the shield braid has to be combed out and cut to an exact length after the jacket is stripped. A no-braid-trim design skips that step: the braid is not cut back separately, so prep is faster, more repeatable from one installer to the next, and leaves fewer loose braid strands that can short the center conductor or end up as debris inside the connector.
What Cable Does the AFA151-20 Fit?
The AFA151-20 is designed for 400-size 50 ohm coax, approximately 0.405" (10.3 mm) outside diameter. Amphenol lists RG-8 and LMR-400. If you are working with a stranded-center, flexible, direct-burial, or fire-rated 400 variant, contact us with the exact cable part number before ordering and we will confirm the fit.
What Tools Do I Need to Install It?
- A crimp tool with a 0.429" hex die (the standard die size for LMR-400 class crimp ferrules)
- A 400-size coax strip/prep tool, or a sharp blade and the strip dimensions from the manufacturer drawing
- A soldering iron and solder for the center pin
- Heat shrink tubing and a heat gun, recommended over the crimped ferrule for strain relief and weather protection
- A 19 mm wrench for the coupling nut, if needed
Installation Overview
- Slide the heat shrink and crimp ferrule onto the cable first.
- Strip the cable to the dimensions on Amphenol drawing AFS-A151-20. There is no separate braid trim step.
- Solder the center pin onto the center conductor. Keep solder off the pin's outer surface and avoid overheating the dielectric.
- Insert the prepared cable into the connector body so the body sleeve seats under the braid and the pin sits at the correct depth.
- Slide the ferrule over the braid and crimp with the 0.429" hex die.
- Shrink the heat shrink over the ferrule and cable jacket.
- Sweep or test the finished assembly before deploying it on a live site.
Always follow the manufacturer drawing for exact strip lengths. This overview does not replace it.
Common Applications
- Land mobile radio base station and repeater feedlines and jumpers (VHF, UHF, 700/800/900 MHz)
- Antenna feedline termination at tower, rooftop, and mast installations
- 2.4 GHz and 5.8 GHz WiFi, point-to-point, and ISM links
- SCADA, telemetry, and fixed wireless data radios
- Test cables and lab assemblies up to 6 GHz
Frequently Asked Questions
Is the Amphenol AFA151-20 crimp or solder?
Both. The center pin is soldered to the center conductor and the outer ferrule is crimped over the braid with a 0.429" hex die.
Is the AFA151-20 waterproof?
Yes. It is rated IP67 and uses a silicone rubber O-ring seal at the interface. For long-term outdoor installs, finish the connection with heat shrink and standard weatherproofing (tape and mastic or a boot).
What frequency range does the AFA151-20 support?
DC to 6 GHz, with VSWR of 1.3:1 or better. That covers VHF and UHF land mobile, 700/800/900 MHz, and 2.4 GHz and 5.8 GHz WiFi and ISM bands.
What crimp die size does the AFA151-20 use?
A 0.429" hex crimp die, the standard size for LMR-400 class crimp ferrules.
Will the AFA151-20 work with LMR-400 UltraFlex?
Amphenol lists LMR-400 and RG-8 only. UltraFlex and other 400 variants can differ in center conductor construction, so contact us with your exact cable part number before ordering.
How tight should the coupling nut be?
Thread it on by hand, then snug it with a 19 mm wrench. Amphenol rates the coupling nut torque at 3 N·m (about 26.5 in-lb). Do not exceed it.
How many times can the AFA151-20 be connected and disconnected?
It is rated for 500 mating cycles.
Is this a genuine Amphenol connector?
Yes. The AFA151-20 is manufactured by Amphenol Fuyang, an Amphenol company, and radioparts.com sources it new through authorized Amphenol distribution.
Why Buy from radioparts.com
radioparts.com specializes in land mobile radio and RF parts, connectors, cable, and accessories. Our team works with coax and connectors every day and can help you confirm cable compatibility, crimp tooling, and the right mating connectors before you order. Buying for a project, a site build, or a fleet? Request a quote for quantity pricing.
Documentation
All specifications on this page are taken from Amphenol customer drawing AFS-A151-20 (part number AFA151-20, title NM-400), Rev 00, first released November 2025.
