High Frequency or HF is the ITU status for the range of radio frequency electromagnetic waves between 3-30 MHz. Another name of it is ‘decameter wave’ or ‘decameter band’ since its wavelength ranges from 1to 10 decameters.
Frequency under HF is called medium frequency or MF. The following band of higher frequency is called Very High Frequency (VHF) band.
The HF band is the great part of the shortwave band of frequencies. Therefore communication with this frequency is known as shortwave radio.
Radio waves of this band may be reflected again in the earth by the ionosphere layer in the atmosphere. This is a system known as skywave or skip propagation. This frequency is great to make communication with long distance across intercontinental distance. It can be HF Mobile Antenna, HF Vertical Antenna, HF Radio Antennaor Portable HF Antenna etc..
It uses greatly in aviation communication, international shortwave board casting stations, weather stations, government time stations, citizen band services and amateur radio.
12 Top Best HF ANTENNA
Top Pick HF Antenna
Common features for HF Antennas
The central way to communicate in the long distance by this band is skywave propagation. Here radio waves directed to an angle in the sky and reflected back to the earth from the levels of ionized atoms in the ionosphere.
For this system, HF radio waves may trek beyond the horizon, around the curve of the earth. Moreover, it may be got at an intercontinental distance.
Therefore appropriateness of the section of the band varies immensely for a complex combination of matters:
- Sunlight/darkness at site of broadcast and welcome
- Sunspot cycle
- Transmitter/receiver nearness to solar terminator
- Polar Aurora
- Solar activity
Mentioned skin communicates between two points at any time. With the frequency, communication is possibly mentioned by these parameters.
- Lowest usable high frequency (LUF) (MUF)
- Maximum usable frequency and a
- Frequency of optimum transmission (FOT)
The normal frequency drops in winter season below 10 MHz in darkness while in summer it normally overcomes 30 MHz. It is up to the angle of happenings of the wave.
It becomes the lowest when waves are directed to the upward direction and higher for having a less acute angle. The Antenna indicates that if the waves graze the ionosphere with a great blunt angle, MUF can be higher.
The lowest used frequency relies on the consumption of the lower level of ionospheres. Absorption is higher for lower frequencies and stronger for developed solar activity.
All absorption happens when the frequency is fewer than 5 MHz at daytime. The consequence of these 2 factors is usable spectrum shifts to the lower frequencies and to the medium frequency range in winter nights. In summer at the daytime higher frequency is useful sometimes in the lower VHF range.
When all factors are perfect, worldwide communication is possible by HF Antenna. Many times it is possible to communicate across and between oceans and countries.
If a band is dead no communication is possible beyond the restricted groundwave. No matter what antennas, power, and other methods are carried to bear.
When a worldwide and transcontinental path is open having a particular frequency, SSB, digital and Morse Code, one may communicate it by using low transmission powers with portable HF Antenna.
Suitable antennas are used in both ends. There is no or little human-made or natural interference.
For this open band, interference on a wide area influences many probable users. This fact is significant for amateur, safety and military radio users of the HF bands.
Best HF Antennas Reviews
The following reviews are made for the HF Antennas that are chosen as the upgraded product in the market
Since everyone tells, the adjusted implications create god kindling but not more else. Though this is a good model, just look up tuning SWR.
Most of the YouTube videos use this radio. You have to set again the maximum forward deflection for SWR meter all times.
You have the option to change the power output of the radio. After that, flip to overturn to detect the SWR. I have got other complaints about this meter. All the objections are almost same.
The power meter on the left seems to be non-linear. It is better to read almost the around the center of the scale regardless of the real power output of the radio.
The performance of the meter is excellent. But it needs 2 different connections such as one for VHF/ UHF and other for HF. It seems to be a pain for the neck when going from HF to VHF and VS [HF Vertical Antenna]
These meters are very active and work great. It has wonderful appearance particularly when you hook the light with a 12 volt source. It will do work for most of the part.
They are not hundred percent accurate, and the calibration knob is very twitchy. It may be better to offer a range which may be applied for further troubleshooting.
Understand your antenna’s SWR as well as complex impedance 530 KHz to 230MHz. Understand complex impedance like series resistance as well as or as magnitude (Z), reactance (R+jX) and phase (degrees).
Find out coax cable loss in dB, velocity factor, length of distance and coax to an open or short. Read return loss, SWR, the reflection coefficient of any frequency simultaneously.
Also, read Capacitance in pF and RF and frequencies inductance in uH. Big screen, easy to read 2 lines LCD screen, side by side meter vividly shows you all information.
This antenna is made with a frequency counter, battery saver, Ni-HH/Ni-CD charger circuit, smooth reduction drive tuning and lower battery. Only set the bandwidth and tune the dial- same as your transceiver.
Complex impedance and SWR are well displayed. Try to get the true resonant frequency of your antenna.
Set up your quad, loop and other antennas, watch SWR and change antenna spacing, reactance and confrontation and yagi change rapidly. You will be able to know what you need to do by watching the display. Both HF Antenna and with HF Radio Antenn are supported with this device.
The NESDR Mini 2+ is refrained from SDR practice, having high accuracy, GPS- rated 0.5 PPM TCXO crystal, re-designed RF-suitable power supply and improve inductors, Japanese fabricated and capacitors compared with generic devices.
Power consumption is reduced at the time of improving lowering and compassion the noise floor.
A strong magnetic suction and superclass telescopic antenna mount base were added here without cost.
The aim of doing it is to ensure a wide array of antenna mounting options. There also added a free SMA adapter to attach SMA antennas with the NESDR Mini 2+.
The ideal set on the cheap device to learn distinct software radio. ADS-B, Amateur radio, trunking, police and fire scanning, satellite images--you name it.
The unit relies on the R829T2 tuner IC manufactured by Rafael Micro. It gives considerable concert improvements over R829T.
They got a frequency power of about 25MHz-1750MHz, though it may be different from one to another unit. Surely there is an RTL2832 IC on board which works as the USB and demodulator boundary.
Who are the users for High Frequency Spectrum?
The significant and common uses of the high frequency spectrum are as follows:
High frequency brand along with amateur operators is very famous for people who take direct merits of long distance communication.
The thrill factor results from having a contact in different conditions. International shortwave broadcasting uses this frequency and seemingly declining number of users.
In a recent year they have been swayed over by the less volatile procedure of communication, but manage HF stations after switch off for back up desires.
However, the progress of Automatic Link Establishment technology relied on MIL-STD-188-141 for frequency choice and automated connectivity.
The high costs of satellite usages promote a renaissance in HF usage for the government networks. For the development of great speed, MIL-STD-188-110C supports data rates up to 120 kilobits/s.
It has developed the utility of HF for video transmission and data communication. Other upgraded development like STANAG 5066 ensures problem free data communications using ARQ protocols.
Some types of communication like continuous wave Morse code transmission along with single sideband voice transmissions are normal in the HF range instead of frequencies for bandwidth conserving features.
But broadband modes like TV transmission are normally forbidden by HF’s small chunk of electromagnetic band space.
Noise particularly man-made connection from electronic devices aims to have an immense effect on the HF bands. At present, concerns have risen among the use of HF on broadband over power lines.
Be conscious; internet access has a destructive effect on HF communications. This is the cause of frequencies on which BPL operates. The aim for the BPL signals is to trickle from power lines.
Some BPL providers setup notch filter to protect some portions of the spectrum, but few amount of controversy over the deployment of this entry method. Other device named as plasma televisions may have a harmful effect on the HF band. It is also harm radio antenna and comet antenna.
For aviation, HF communication system demands all trans-oceanic flights. This system shares frequencies below 2MHz to add 2182 kHz international distress and demanding channel.
The upper portion of the HF shares many features with the lower part of the VHF. The section may not allow amateur radio which is used for communications.
They are CB radios around radio control devices, studio-to-transmitter (STL) radio links, and local communications.
Some radio frequency identification tags utilize HF. These tags are usually named as RFID's or HighFID's (High Frequency Identification)
Buyers guide before purchase!
Choosing best HF Vertical
For lots of amateur radio workers, a HF vertical antenna is the only alternative to set up an HF antenna. They may live in a small town where there is no suitable trees or other types of antenna support. This can hand the load of dipoles.
There are lots of products on the market. From them, you have to choose the best one. This is a difficult task no doubt. Some portable hf antenna also can be include with the list.
On online you will get much information about the products. I hope this short article will help you lots to choose the exact vertical antenna for your need. Buyers sometimes become confused when they see lots of products before their eyes.
Trap verticals are great in the market for a long time. I found an HF antenna in 1971and it was a shy-gain 14AVQ.
These verticals apply traps which are parallel booming circuits. The trap makes the antenna work as it were a ringing quarter wave verticals.
Suppose when 14AVQ is used on 10m band, the lower part of the antenna is lively. If operating for m, the whole piece of the antenna is active.
Trap verticals ask for radials to function successfully and the better, the merrier. Obtain it for consideration, when taking a decision or do not buy a trap vertical.
At present, some manufacturers made vertical antennas which may not want radials. GAP antenna is the only manufacturer that gives these types of antennas.
The manufactures demand that these antennas are very efficient than catch verticals. Now many amateurs apply them with getting a good result.
There are few demerits. Therefore it is difficult to tune. They demand to mount for some detachment from the ground.
The cause is that they are vertical dipoles. If the last of the antenna is very near to the ground, capacitive pairing may detune the antenna.
Non-resonant vertical antennas
A low graded vertical antenna which is becoming very popular. The name of this antenna is a non-resonant HF vertical antennas.
Such kind of antenna is LDG S9v43 vertical antenna although some other producers also make such type of antennas.
The reason for becoming very popular is that one can use it across a wide rate range. The significant frequency of this antenna is about 5.4 MHz. By using an antenna tuner, you may use the antenna for all groups from 80m to 6m.
The tuner may be set up in your hut, but for lowest beating, you desire to locate the tuner close to the bottom of the antenna.
Better not to try it with an internal tuner for your rig. For some antenna, the impedance may be fairly high. All internal rig auto tuners may not have enough range to give a 50 ohm match.
These types of antenna need radials. As far there is no exact procedure to measure the length of radials, but they must be at least 0.2 wavelengths for the lowest frequency.
We bring all types of LDG vertical antennas. The LDG S9v31 antenna is 31 feet high and covers 40m; The LDG S9v43 antenna is 43 ft. High and covers 80m – 6m. Moreover, the LDG S9v18 antenna is eighteen feet high and covers 20m – 6m. All types of antenna use heavy duty telescoping fiberglass sections. The antenna is lightweight and self- supporting. They are also very simple to set up
Vertical antennas are very dear to people for HF operation. The cause is that it adjusts with a small garden well.
They are two types. One is best to install on the ground level, and other is good to install on the topmast.
All verticals require a better earth and seem as if they need no earth. It is better to install on the topmast that is half wave vertical dipoles instead of quarter wave verticals.