The Antra AT-MB04 UHF 4 bay outdoor antenna at $20 is the cheapest available outdoor antenna. It is a clone of the Channel Master CM4221 which sells for over $50.

The manufacturer states that the antenna has the following features:

  • High gain across UHF CH20-69
  • Up to 45 miles reception range (typical range)
  • Easy to install (all elements are preinstalled)
  • Strong ALL SOLID aluminums design, very light (less than 3lb)
  • Transformer pre-installed with 75 Ohm output
  • Dimensions: 34" x 21" x 3"
  • Weight: 4lb
At $20 the Antra AT-MB04 antenna is almost as cheap as building your own antenna.

The antenna comes with an instruction booklet and a warning flyer. The warning flyer states:

Warning. Antenna is folded in the box!! Please fully unfold the elements before an assembly work is proceeded. Please read instructions included for safety and installation guide.

Though the warning flyer states that the antenna is folded in the box. It is not. When removed from the box the antenna is fully assembled.

The instruction booklet is 14 pages. The first 7 has instructions in English and the last 7 has instructions in French. It also has decent black and white pictures on the assembly of the antenna. Since the antenna was made in China, expect the usually spelling and grammatical errors. Some have been corrected here.

The first thing that you will notice when you remove the antenna from the box is that it is light weight. Weighing a little over 4 lbs it looks sturdy enough to be mounted outside. There was a small rattling sound coming from the main bar of the frame. This was probably from a piece of metal that went inside the main bar when the elements were screwed in. Manufacturers to reduce cost don't pre-drill mounting holes. The 4 bays and the 4 reflectors on the antenna are not adjustable. So if you want to point the entire antenna has to point in the same direction.

The transformer is located in the middle of the antenna. The antenna does not come with any cables. In the plastic bag with the instructions there is a weather boot to protect the terminal end to the transformer when you would connect the cable. Slip the weather boot over the cable, screw the cable on to the transformer end and then move the weather boot to cover the connection.

The instructions has an extensive section on how to assemble the mounting clamp. However you will be pleasantly surprised to find the clamp has been pre-assembled. The mounting clamp can be used to attach the antenna to either a satellite dish arm or an antenna mast. The clamp is adjustable and will fit both.

The antenna has a 90 day manufacturer's warranty. The warranty does not cover removal and shipping to the dealer or manufacturer. It also does not cover weather related damage.

Installation Instructions for AT-MB04

Watch for wires!
Never Install an Antenna too close to Electric Power Lines.

Installation of this antenna near power lines is EXTREMELY dangerous.
Make sure the installation spot has a SAFE DISTANCE from the Electric Power Line.
For your safety, please follow the installation instructions.

Safety Instructions:

1. Antenna Assembly should be complete on Ground.
2. Check for power lines around the building.
Always maintain a safe distance to power lines!! Safe distance >=2 * (height of mast assembly + height of antenna)
3. Never use a metal ladder.
4. Do no install this antenna during an icy or windy day.
5. Never touch the electric power in any way!!
6. Have a friend as a spotter when you're on the roof. They can see things you can't.
7. Mast, lead-in and metal guy wires are excellent conductors of electrical current - keep them away from power lines too.
8. Be sure your family and friends understand the danger of touching an overhead power line. Tell them never to try to remove any objects in contact with a power line - CB, TV antenna or anything else.
9. Ground the mast and antenna before the installation is finished.

Choose Best Site to Install Your Antenna

1. Make sure to keep enough safe distance from the site to Power lines. Minimum 2*(Height of mast assembly+height of antenna). The larger the safe distance the safer. If you are unable to maintain this safe distance, stop! Get professional help.
2. Try to keep antenna as far as possible from high trees or other obstructions to get better performance without compromising the safety distance. The far the antenna from obstructions the better it performs.
3. The antenna should be 5-10 feet higher than the rooftop to get its top performance. The higher the antenna the better it can receive signals.

Note: This Antenna Elements is folded in the box. Make sure the antenna is on its fully unfolded position before any further assembly steps.

Installation The Antenna

Assembly the antenna in accordance with the instructions included on Page 6 and Page 7. Be sure do this job on the ground for your safety. If no rotor is used for the antenna. Do not tighten the mast until the antenna has the best direction and reception.

Roof Mounting

Tripod Mounting
Tripod mount must be anchored to the roof securely. Guy wires are required if the master is 10 feet or more.

Guy Wire Mounting
One clamp brackets should be anchored to the roof securely, the mast should be surrounded by 3-4 buy wires, equally spaced and securely anchored on the roof.

Side Wall Mounting
Use two brackets 2-3 feet spaced vertically, anchored to the wall securely. Put the mast between the two brackets.

Signal Tuning Procedures
For all the above mounting type with a rotor, skip to step 4
For all the above mounting type without a rotor

1. Connect the transmission line to signal meter or a test TV (on a known local over the air channel)
2. Turn the mast and fine tune the antenna while monitoring signal changes.
3. Tighten the mast when the best antenna position is found
4. Tighten all screws to make sure the antenna mast is tightened.

Assembly Instructions

Technical Data
Frequency 470-862 Mhz
Channel 21-69
Imped 75 Ohm
No. of elements 16
Gain 10-13dB
Front-back ratio 22dB
Beam width Honz/vertical 60" / 32"
Length 840mm

Antenna Structure

Note: I: Reflector II: V Type Elements III: Clamp IV: Transformer Box V:Antenna Carrier
Operation Instructions

V type Elements should be pulled all the way from Reflector as shown in the picture

A "click" sound will occur when the elements is on its fully unfolded position.

Clamp Parts

1. Wing Nuts
2. Clamp Part A
3. U Type Bolt
4. Bolts and Washers
5. Clamp Part B
6. Clamp Part C

Clamp Installation

Step 1: Pull the Elements from reflector as Operation Instructions shows. Put 6 between IV and V (Antenna Structure See Page 6)

Step 2: Insert 3 into 5

Step 3: Place Assembly 3&5 on Antenna Carrier V make sure holes on 5 and 6 are aligned properly.

Step 4: Attach 5 and 6 with bolts washers should be applied on top of 5.

Step 5: Assembly 2 to U Type Bolts 3.

Step 6: Apply Wing Nuts 1 onto U Type Bolts 3.

Step 7: Secure Antenna Mast with Antenna by tightening U Type Bolts 3.

This Antenna can be tilted up to 30 Degrees for flexibility.

F Type Weather Boot Installation

F Type weather boot
Assembly onto the cable
Connect Cable to the F connect on the transformer box.


  1. Anonymous // December 3, 2010 at 3:18 PM  

    This antenna is a poor clone at best. It suffers from one very big design flaw which can be seen in the second and third photos. Notice the spots where the pair of aluminum wires that run from the top set of bow ties to the bottom set of bow ties cross over each other in a X fashion. One wire runs straight over while the other is curved like a half circle as it runs over the first. That half circle wire is longer than the straight one. Those two wires need to be the EXACT same length or else the reception suffers noticeably. A decrease of 33% or more, I'm afraid.
    There are other identical looking antennas that don't have this flaw and they are made by the same factory. Two of them are the Eaglestar Pro and Volfe HD-007. These have the same size box and identical spec/instruction sheets. The price is the same, if not lower.