Review of the Icom IC-R20 scanning receiver. What can it do?

Appearance

Icom IC-R20 is quite large, its dimensions are 60×142×34.8 mm. But it weighs little — only 320 g. The screen is monochrome, liquid crystal with green backlight, occupying about a third of the front panel of the device. The rest is divided between the keyboard and the speaker.

On the top end, there is a standard 50-ohm BNC-F connector for connecting an external antenna. The kit includes a telescopic antenna that can fold 180 degrees. This is convenient for transportation — however, after 15–20 assembly cycles, you have to tighten the screws. Any external antenna can be easily connected to the connector.

Also on the top of the device, there are two DIAL knobs, labeled L and R. Their functions can be reassigned in the settings, but by default, one adjusts the volume, and the other is used to control the frequency.

On the left side of the device, there are three rubberized buttons. The top one is responsible for monitoring. While you hold it down, the speaker will hear the air on the selected frequency, even if there is no useful signal. The two buttons below can equally work to change the volume or frequency.

On the right side, under rubber plugs, there is a combined headphone/CI-V input, a power supply connector, and a separate Mini-USB input. Interestingly, the audio jack can also be used as an antenna. This is necessary for better reception of FM broadcast stations when the capabilities of the built-in magnetic antenna are insufficient.

On the back side is the battery compartment. By default, it is equipped with a rechargeable Li-Ion battery BP-206, the same as in the Icom IC-R3. But the main feature is that if the battery is dead and you have no way to charge it, you can replace it with three regular AA (LR6) batteries or accumulators using a special plastic insert. This is especially relevant for those who spend a lot of time outdoors. A full charge will last a maximum of 11 hours, but only if one frequency is received at the same time. I will talk about this feature a little later.

For wearing on the belt, the kit includes a simple MB-98 clip, the same as most modern portable radios. It is quite convenient, but Icom has a slightly more interesting version of this accessory - the MB-86 swivel quick-release clip. It allows you to easily remove and hang the radio scanner on the belt without disconnecting the clip.

Optionally, you can purchase the BC-156 charging cup and LC-158 case. The first solves the problem that the scanner is quite unstable on a flat surface and helps to charge it without constantly pulling the rubber plug on the DC connector. The radio scanner itself is quite durable and has passed tests equivalent to military MIL-STD 810 (C, D, E, F). At the same time, it does not have an official dust and moisture protection rating. So in the field, it needs to be additionally protected with a case.

Technical specifications

Receiving path

The hardware part of the Icom IC-R20 is very interesting. This radio receiver is capable of receiving signals in a very wide frequency range: 150 kHz - 3 304.999 MHz. In the American version, the 800 MHz spectrum intended for mobile communications is cut out according to legal requirements.

The most interesting thing is that the device can receive two frequencies simultaneously. Someone might say that any Chinese transceiver for $20 can do that. This is true, but inside it will be the simplest receiving path on a direct amplification chip. Receiving two frequencies simultaneously is implemented by fast switching between them. That is, when you have a useful signal on one frequency, it will not be received on the other.

Icom IC-R20 uses a completely different approach. Inside it, there are actually not one, but two receiving paths. This allows you to truly receive two frequencies at the same time. Instead of direct amplification, a triple conversion superheterodyne is used. The following frequencies are used as intermediates:

1. 266.7 MHz.

2. 19.65 MHz.

3. 450 kHz.

This achieves high selectivity and excellent mirror channel suppression, along with fewer intermodulation distortions and better stability when receiving weak signals. However, such an implementation has several important features and imposes certain limitations. When you enable the reception of two frequencies simultaneously, it connects the second path, which effectively doubles the power consumption and reduces autonomy.

An additional limitation is that when operating two receiving paths, the entire declared range cannot be used. The maximum reception frequency and modulation are limited:

• first path (VFO A): 150 kHz — 469.999 MHz (LSB / USB / CW / AM / FM / WFM);

• second path (VFO B): 118 MHz — 174.999 MHz and 330 MHz — 1,304.999 MHz (AM / FM / WFM).

That is, in the mode of receiving two frequencies simultaneously, you cannot select a range above 1,304.999 MHz. In most cases, this is not necessary, so it should not be considered a disadvantage. If the second radio path is turned off, the entire declared range becomes available.

Another feature of the Icom IC-R20 is the built-in 20 dB attenuator. This is required in a number of cases, including receiving strong signals to protect circuits from overload or to improve the intelligibility of weak signals against powerful interference.

Scanning

Let's move on to one of the strongest points of this receiver. It scans the airwaves at a speed of up to 100 channels per second in VFO mode. If working with channels stored in memory (MR), the speed will be about 30 channels/s. This is three times higher than that of the Icom IC-R5.

It is worth noting the flexibility of parameter settings. The device allows you to scan:

• all frequencies in all available reception ranges;

• all frequencies within a single selected range;

• all frequencies within an arbitrary range between two user-specified frequencies;

• sequential scanning of all frequencies in specified memory banks;

• sequential scanning of all frequencies in specified memory banks except those marked as SKIP;

• sequential scanning of all previously unfound frequencies except those marked as SKIP.

Perhaps the most interesting feature is the automatic saving of all found frequencies to memory. This simplifies the search and allows you to later study each detected frequency. If necessary, you can also record the received signals on a digital voice recorder.

Memory

I should mention that this radio scanner was released in 2006 and was produced until 2014. It had a total of 1,250 channels, which were divided into three segments:

• 1,000 regular;

• 50 user-defined, setting the boundaries of the scanning range;

• 200 channels used only by the autosave function during scanning.

In addition, the IC-R20 was equipped with 32 MB of flash memory for recording signals on a digital voice recorder. Depending on the selected quality - high, medium, or low - it was possible to record up to 260 minutes, divided into 32 tracks accordingly. This function is most in demand when receiving signals from satellites, the flight time of which is limited.

For example, the ISS flight takes about 10 minutes. On days when SSTV images are broadcast from the station, radio amateurs from all over the world try to receive and decode them. If you have an Icom IC-R20 at hand at this moment, you can simply turn on the signal recording with one button and decode it later by connecting it to a computer.

Alas, a significant fly in the ointment is added to this barrel of honey by the proprietary recording format. When trying to download files using the native software, you get a set of tracks in ICW. Fortunately, there is a free converter program on the network that converts ICW tracks into regular WAV files. In general, if you use high recording quality, there are no problems with decoding SSTV signals.

Other features

I cannot fail to mention that the Icom IC-R20 has a primitive, but still a spectroscope. Now, in the heyday of SDR receivers, it is difficult to surprise anyone with this, but 18 years ago not every receiver had the ability to detect activity on adjacent frequencies.

It worked like this: you selected the scanning range (in the photo - 25 kHz), and the receiver quickly "ran" through it without sound with a certain step and recorded the signal level, simultaneously drawing it on the screen. This formed a picture where the peak signal values were clearly shown. Then you could tune in to them and listen to them one by one. Of course, this gave only a very rough idea of what was happening on adjacent frequencies. But it's better than nothing.

Opinions of radio amateurs

Icom IC-R20 left no one indifferent. Those who had the chance to use this radio scanner noted its convenience and high scanning speed. 100 channels per second — it was incredibly fast for 2006! Of course, the IC-R30 model that followed the IC-R20 doubled this figure, but such an improvement was hardly really needed.

The only drawback is the small memory size. Given the high cost of the device, this caused bewilderment: since flash drives with 512 MB were already quite sold at that time, at least 128 MB could have been inserted. Probably, there is some reasonable explanation for this, but it is unlikely to satisfy a radio amateur who counted out 550 dollars for this miracle of technology.

The closest competitor to the Icom IC-R20 was the AOR AR-8200 scanning receiver. It was produced in three versions: mk1, mk2, and mk3. Each subsequent version significantly expanded the receiver's capabilities, but still could not catch up with the Icom competitor in some parameters.

Nevertheless, most radio amateurs note that the sound quality of AOR is significantly higher, as well as the ergonomics of control. Although, in my opinion, this is a matter of habit: even weak signals are quite distinguishable, and for better quality, you can connect an external speaker or headphone.

Another competitor, besides the AOR AR-8200, was the Alinco DJ-X2000 radio scanner. But in terms of technical characteristics, it is significantly more modest. The scanning speed is only 30 channels/s in VFO mode, and when switching to MR, it even dropped to 7 channels/s. The voice recorder also held only a few minutes of recording.

Nevertheless, Alinco has its own highlight — a built-in frequency counter. It very quickly determines the frequency of the nearest radiation source and instantly tunes to it. In some cases, this is very useful. Alas, but Alinco devices did not become popular, including among Russian users. And they are harder to get than the same Icom or AOR.

What is the result

Icom IC-R20, 10 years after its discontinuation, remains one of the most convenient and functional radio scanners. Even considering some drawbacks, such as the small amount of built-in memory and proprietary recording format, it offered an excellent set of features: fast scanning, wide frequency range, digital voice recorder, and even a simple spectroscope.

Its main drawback for 2024 may seem to be the complete lack of support for digital communication modes. Despite this, its impressive characteristics, the presence of two receiving paths, and the ability to be remotely controlled allow it to remain relevant. This device has become a kind of benchmark for many radio amateurs.

Have you ever used the Icom IC-R20? If so, tell us about it in the comments.