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Diamond X300A Dual-Band Base/Repeater Antenna 144–148 MHz & 435–450 MHz High-Gain Vertical Base Station VHF/UHF Antenna with UHF Female Connector and Fiberglass Radome

Based on 98 reviews
Condition: New
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$183.99

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Availability: Only 4 left in stock, order soon!
Fulfilled by Hamcity com

Arrives Wednesday, Nov 11
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At a glance

Condition
New
Model
X300A
Color
White
Antenna
DualBand Base / Repeater Antenna
Impedance
50 ohm
Maximum Range
184 feet
Warranty
1 YEAR

Features 10

  • High-performance dual-band base and repeater antenna engineered for 2 meter (144148 MHz) and 70 centimeter (435450 MHz) amateur radio operation, delivering strong transmit and receive signal performance across both bands
  • Achieves elevated gain of approximately 6.5 dBi on 2 m and up to 9.0 dBi on 70 cm for expanded range and clearer communication on local nets, repeater links, and fixed station setups without complex tuning
  • Constructed with a rugged fiberglass radome and corrosion-resistant hardware designed for long-term outdoor deployment on towers, masts, rooftops, or permanent installations in varied weather conditions
  • Factory pre-tuned design with broad frequency coverage and VSWR typically below 1.5:1 ensures efficient RF transfer, simplified installation, and reliable performance right out of the box

Description

The Diamond X300A Dual-Band Base/Repeater Antenna is a premium-grade vertical antenna designed for amateur radio base stations, repeater sites, and fixed station communications requiring high-gain performance across the 2 meter and 70 centimeter bands. Covering 144–148 MHz and 435–450 MHz, this antenna combines broad frequency coverage with enhanced gain characteristics — approximately 6.5 dBi on the 2 m band and up to 9.0 dBi on the 70 cm band — to provide elevated transmit reach and improved reception sensitivity compared with lower gain alternatives. Built to withstand rugged outdoor environments, the X300A features a sturdy fiberglass radome with overlapping outer shells and corrosion-resistant stainless-steel hardware. The robust mechanical design delivers excellent wind resistance (up to about 112 mph without ice) and long- lasting structural integrity in varied weather conditions. A factory-pre-tuned structure with optimized C-Load and linear phase shifter technology enables broad band performance and low VSWR without the need for field adjustments, simplifying setup on rooftops, towers, or permanent masts. This antenna accepts standard mast diameters (about 30–62 mm) and terminates in a UHF female (SO-239) connector that seamlessly integrates with low-loss coax feed lines for typical VHF/UHF installations. Its DC-grounded design and rugged water-proof joint couplings ensure stable performance in wet or corrosive environments. The X300A’s combination of high gain, durable construction, and easy integration makes it an excellent choice for amateur radio operators, repeater builders, public safety networks, and club installations seeking dependable dual-band base station performance.

Specs 13

Antenna DualBand Base / Repeater Antenna
Brand Diamond Antenna
Color White
Impedance 50 ohm
Maximum Range 184 feet
Manufacturer Diamond Antenna
Number of Packs 1
Unit Count 1 Count

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Nov 11

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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View our full returns policy here.

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Top Amazon Reviews


Very happy with performance!
I am very happy with this antenna so far. It was easy to assemble an get up onto the roof. Mounted 25 feet above ground level I can hear 2 meter stations well over 50 miles out in every direction. This antenna along with a LMR-400 feeder cable is giving me a SWR of 1:1.02 in the middle of the 2 meter band. With my base radio output set at 10 watts I am full quiet on any repeater 20 miles or less. Cranked up to 50 watts on this antenna, if I can hear a station or repeater they can easily hear me. I do not regret buying this for my first base station antenna. I know guys who can use a coat hanger and a pie plate and be able to tune in some impressive signals. Being new to HAM I wanted something that performed and was reliable. So far this antenna has out performed in both areas. I have not been through any storms or much rain at all since installation, will update if I see a change in the future. ... show more
Reviewed in the United States on October 20, 2022 by Nathan

Great antenna
I’m very happy with this antenna. This is my first ham antenna so I don’t have anything to compare it to but it was simple to assemble and gives a very low see across both bands. Looks very professional comes with everything you need to attach it to a mast. I’ve had great reports of my signal and as long as the repeater antenna is high, I’ve been picking up stations 40-60 miles out with S9. ... show more
Reviewed in the United States on December 26, 2020 by Max C. Anderson

Awesome !
This Antenna is kick ash ! I would say it’s pre-tuned, but no antenna is tuned unless I do it. Came out of the box 1.04 which is darn good if you ask me, it did tune to 1.00 but I’m a stickler. It’s all bout the Antenna, not the power.
Reviewed in the United States on December 9, 2023 by Chris

Low SWR, great range!
This antenna works really well. Flat 1.1 SWR the first time setting it up! Great range!
Reviewed in the United States on January 11, 2025 by Amazon Customer

works well for 2M/70cm amateur radio base station
I re-used the existing coax that I was using for a 3/4" homemade J-Pole antenna over the past approximately 10 years. I wrapped the joint and the feed point with electrical weather seal as mentioned in numerous other reviews so hopefully this will last a long time. I did not perform a before and after test for range but did run my Comet antenna analyzer on the antenna with good results for SWR on both bands. I have a split-level house, so it is mounted on a 2 inch diameter 10 foot pole that I was using for an external long range TV antenna and the J-Pole above that. This antenna is the only antenna that I have up on the house now. ... show more
Reviewed in the United States on March 27, 2024 by R Rieck

It works
Height is important. I put the 10ft antenna on top of a 21ft flag pole. Got it way above my roof line (a chimney mount was not an option for me). Started receiving with clarity signals that were almost unintelligible previously. Very pleased. The construction of the antenna is sturdy. It's rated for wind speeds beyond what I typically get in my region. I'm expecting it to last for years. ... show more
Reviewed in the United States on July 9, 2020 by Sheldon J Gana

I really like this antenna ❗️
Great value. Easy setup. I have it mounted on plumbing pipe up 12 feet or so. Have 6 meter horizontal below as picture shows. Get over 40 miles on simplex. Works for me. KJ7WWB
Reviewed in the United States on July 26, 2021 by Ericb

Diamond Quality
I replaced my Comet CP-1 with this 10 footer hoping to hear a bit more. 50 mile repeaters and the ISS no problem at 20 ft mounted height . Extra assembly tips such as lock tight and clear silicone sealant on joints and screws.
Reviewed in the United States on December 18, 2022 by Earl
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