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Milcom Receiving Equipment

From The RadioReference Wiki

The VHF/UHF Milcom Receiver

A receiver for monitoring VHF and UHF Milcom must cover, at a minimum, the 225-400 and 138-144 mhz ranges. Mil flights sometimes also use the civil air band (118-136 mhz) range. With the exception of the civil air band (where AM mode is the norm) and the VHF Low/162/406 Mhz bands (FM), either AM or FM mode transmissions may be heard in these ranges, so the ability to change mode independent of the frequency being received is very important.


If you are using a scanner, one with a fast scan rate is necessary when scanning a large number of milcom channels. Most milcom aircraft communications are short in duration, and after a while you will be accumulating and scanning a large number of frequencies. What qualifies as a 'fast' scanner is subjective. As an example, the Uniden BC780XLT is a popular mil air scanner which can scan 100 channels per second.


Good sensitivity in the above frequency ranges is a must. You will be receiving milcom aircraft signals originating from hundreds of miles away, and they can be relatively weak. Dynamic range (resistance to overloading) is also important, particularly if you live in an urban area. This will help you avoid hearing signals such as FM and TV where they don't belong. It's not unusual to find that you need to add filtering. This is very much determined by your local RF environment. See our Scanner Accessories page for links for various kinds of filters


As a rule, handheld models will be more susceptible to overloading than base radios. Handhelds are not always able to cope with a signal coming from a large antenna; they're simply not designed for it.


Software Defined Radios

This is easily the king of the hill. Very fast searches and flexibility are just two attributes; in addition you can get a RTL-SDR for next to nothing. See our Software Defined Radios article for a great deal more on this subject, including links to applications and plug ins.


Hobby level SDRs have a serious fault with overloading. Most simply don't have enough filtering in the front end (or any at all) to prevent FM, TV and other signals from intruding.


Widebanded Radios

See the following links for extensive lists of receivers;


There has been no known development from either Alinco or Yupiteru regarding wide banded handhelds in several years. In the 80s, Yupiteru radios used to be very popular for many applications that required wide frequency flexibility. Getting service if needed may not be possible.


Base Models

Older Icom radios like the IC-R7000 aren't really set up to sample many frequencies quickly; they are best used to monitor one or a few channels. This is because their scan rate is very slow.

However the IC-R8600 is proving to be very popular. It has a much faster scan speed and numerous advanced features. There have been numerous comments in the Icom forum at RadioReference. See the links for more information.

AOR has had many issues with their base units, and recent traffic suggests that trying to get service is difficult. Their old AR8600 has many issues with overloading; software that runs under Windows 10 is difficult to find. The DV1 initially started off strong, but a recent development involving failures of the USB ports has been a serious issue. The future status of this radio is uncertain.

AOR's AR5700D seems to have issues of its own. It's been reported that, in order to update the firmware, it needs to be returned to AOR Japan, sometimes more than once. See the linked thread in the wiki article for more information.


Radios in a box

In the 80s and 90s, Icom came out with their 'radios in a box'. These weren't SDRs, but were instead radios whose basic functions were accessed by a PC. A couple could work without a PC at all. These were;

Generally speaking these radios were hot for their time, but had numerous issues with overloading. In addition, the 100 and 1000 wouldn't allow the user to change the default mode assigned to a frequency. Trunking Project 25 systems is possible but may need some modifications to make this work. These units have since disappeared from the market, but you might find them on places like eBay.

Bonito's Radiojet 1305 on paper, looks to be an impressive unit, but there has been very little written about it. The native software has a serious flaw- it is incompatible with Windows 10. To their credit, Bonito has admitted to this issue, but it is unknown whether it has ever been addressed.


Handhelds

Icom's older handhelds like the IC-R20 could make a decent radio; however it's a bit slow in sampling frequencies. In addition, Windows 10 compatible software is becoming harder to find. The IC-R30 is a much better performer, with a much faster sample rate. See the links for more information.

AOR's older AR8200 was generally thought of as a good performer, but it was greatly hindered by an overly-complex user manual and programming interface. The DV10 has been plagued with many issues, including firmware problems. Whether the many faults it has will ever be addressed is questionable.


Scanners

This is where milcom scanning started, and still has a large base today. Various models can be found on the Uniden Scanners and Whistler Scanners pages. Be sure to check their specifications carefully - older models such as the BC796D can't trunktrack in the 380 Mhz band, where many bases have installed Project 25 systems. Some can't change the default mode for a frequency (for example the 138 Mhz band is set for FM mode and it can't be changed).


While Radio Shack Scanners and GRE Scanners are an attractive alternative, keep in mind that both companies have left the scanner market. Therefore getting any servicing might be very difficult (the exceptions are the GRE PSR-800, RS Pro-18 and 668, which can be upgraded to a Whistler WS1080 via the Whistler Official Upgrade (WOU)). In general, these scanners have more issues with overloading than the Unidens.


Note that the Unidens, starting with the HP1, and the Whistler object oriented scanners (except the WS1040 and WS1065) contain a copy of the RadioReference database on a SD card. This also includes GRE's PSR-800, Radio Shack's Pro-107, Pro-668 and Pro-18. How they are accessed between the distributors is quite different. See the individual models for more details.


See the Radio Control Software article for software support of these radios.


Each of these manufacturers are extensively covered in the RadioReference forums. Be sure to ask your questions there.


Antennas

Unless you are close to a military base or airport, the little antenna that comes with handhelds (often called a 'duckie') or a little whip (for some mobile or base units) will not be very useful. Milcom communications can cover a wide range of frequencies and aircraft can be a long way off. Consequently you will need an antenna that is broadbanded (covers a wide range of frequencies), mounted high, away from surrounding objects and fed with a good grade of coax. Discones are a common choice, but there are other designs, too.


Sometimes (especially in urban areas) broadbanded antennas can contribute to hearing signals where they don't belong, especially when using radios (or even SDRs) with poor resistance to overloading. Additional filtering is often required in these situations.


Here are a few examples of broadbanded antennas. See our Scanner Antennas page for other antenna links as well as coax suppliers. Additions to this article are solicited.


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