FM 76-108 MHz (Stereo)
LW/MW/SW 150 kHz - 29.999 MHz (continuous) AM, SSB, AM Sync
The radio has an unusual clamshell design, with a 51x32 mm LCD screen that displays the band, frequency, and information about whether the radio is in USB, LSB/CW, Upper Sync, Lower Sync, AM, or FM mode. The sound quality is quite good and incredibly crisp, especially on FM, which is in stereo through the headphones. The ICF-SW100E is identical, but is sold without the active antenna or AC power adaptor.
To many listeners, perhaps the most important characteristic of a shortwave radio is the sensitivity. To make a fair comparison, it's necessary to ensure you're using the same antenna and same bandwidth setting. On the ICF-SW100, the bandwidth cannot be changed, and was close to halfway between the "narrow" (4.3 kHz) and "wide" (9.4 kHz) settings of the Sony ICF-2010. The whip antenna and ferrite loop on the unit are both too small to pick up many signals. The ICF-SW100 comes with an AN-100A active antenna which helps a little, but not much. An external antenna is essential for this receiver.
To compare the sensitivity with the ICF-2010, I connected an LF-H800 active antenna to each receiver and tested their ability to detect faint signals. Unquestionably, the 2010 was slightly more sensitive at both selectivity settings, with the very faintest signals having noticeably more noise on the ICF-SW100. This was not the result of the better high frequency audio response of the ICF-SW100, but seemed mainly to result from the broader bandpass. In any case, the difference was very slight in HF. To compare the sensitivity in the LW and MW bands, I placed each receiver inside a large tuned loop antenna. In the LW band as well, the 2010 was slightly more sensitive. Some beacon signals that were barely detectable on the 2010 could not be heard on the 100. However, France Inter at 162 kHz came in loud and clear, and the SW100 had no noticeable drift on any frequency. There is, however, a noticeable brief warbling sound every time you change the frequency as the tuner settles into the new frequency. This is undoubtedly caused by compromises in speed in the design of the PLL. The large minimum AM tuning step is another consequence of compromises in the synthesized digital tuning.
When using the attached whip antenna, the ability of the SW100 to reject phantom signals was almost as good as the ICF-2010. However, the SW100 was far more susceptible than the 2010 to overloading, and when a good external antenna was connected, strong local AM broadcast stations could often be heard in the LW and HF bands. However, with the supplied antenna, these radio faux pas were fairly rare.
The SW100's susceptibility to overloading hits it hardest in the MW band. For example, after the recent hurricane, I tried connecting an external antenna to the SW100 to listen to WWL in New Orleans at 870 kHz. The external antenna overloaded the SW100, causing a local station at 630 kHz to show up at 870 and making reception at 870 impossible. This did not happen with the 2010. However, unlike the 2010, you can select upper vs. lower AM sync in the SW100 without changing the frequency. This is cool but it doesn't help much.
I took the ICF-SW100 on a recent trip to Europe to test its ability to pick up signals in the longwave broadcast band. Here, the tiny ferrite loop again caused disappointing results, with almost no signals being detectable from my hotel room. However, when I put the radio inside a 1 x 1 x 1 foot square loop antenna, the LW band from 150 to 260 kHz was suddenly crammed with strong signals. This illustrates the importance of an external antenna for this radio. And yes, interference from BPL is a problem in Europe. If the radio is within 5 feet of any electrical wiring, the entire HF band is covered with computer-generated hash.
The five biggest faults with the ICF-SW100 are:
Since there's no tuning knob, you must use the up/down buttons or enter the frequency directly. With direct tuning, you press "Direct", followed by the frequency, and then "Enter". This is more keystrokes than is necessary on some other radios. The frequency can be abbreviated if it's divisible by 1000; for example "Direct" 1 0 "Enter" will set the radio to 10,000 kHz. Tuning steps are 1 and 5 kHz for SW, 1 and 3 kHz for LW, 1 and 9 or 10 for MW, and 0.1 and 1 kHz for SSB. The MW tuning step is automatically adjusted depending on the time zone you set the clock to. I was unable to test whether the FM preemphasis is automatically set according to the time zone. Since the manual doesn't mention this, it seems unlikely. The sound is blanked out for about 50-100 msec when you change the frequency. Pressing and holding the tuning button causes it to scan. The scanning will jump to the bottom of the current "band", which can be below the starting frequency, when it reaches the top of the band. The bands are upper and lower limits set by the manufacturer. This can be very disconcerting, since there's no other indication of where any particular band starts or stops.
Another problem is the alarm clock. The SW100 has two alarm clocks or "timers" whose operation is very non-intuitive. After a few months, I discovered that the radio had been automatically turning itself on every night at midnight. It turns out that the timer buttons, along with the other clock functions, only work when the radio is turned off. For example, pressing the "FM/AM" button while the radio is off activates Alarm #1, while pressing the "AM Band" button activates Alarm #2. If you accidentally press "FM/AM" while the radio is off, you will receive a rude awakening the next time the radio thinks it is midnight. Fortunately, the radio can't make a very loud noise. But it could be loud enough to get your suitcase in big trouble in an airport.
The radio emits a small amount of RF hash at 3MHz due to the display electronics. The back cover is difficult to remove, but once it was removed, I was surprised to see that the radio still uses mostly discrete components--albeit very small ones--instead of ICs.
You can enter a five-letter ID code for each of 25 memory presets. However, unlike the Winradio, the ID code isn't displayed automatically if you tune the same frequency manually. The LCD screen has a very faint backlight that turns itself off after 30 sec; in contrast to the 2010, pressing other buttons on the radio doesn't prevent the light from going off.
Conclusion This is a well-made radio that is excellent for taking on trips, not least because the AM and FM broadcast bands in many countries are different from the allocations in the US. However, the necessity for cramming an antenna into your suitcase somewhat negates the benefit of its small size. The lack of a tuning knob, the small size of its buttons, the absence of a signal strength indicator, and its susceptibility to overloading mean that you'd probably not want to make this your primary radio.
From the What were they thinking file: The SW-100 has been replaced by a more recent model that looks like a lady's compact, but the specifications are almost identical. If it's not actually pink in color, it probably should be.