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I sold about 80 radios on eBay, but there were just a few that nobody wanted. I went through those to see if there was anything worth saving from storage. One radio looked like it might be worth further study, a Kaide KK-MP903.

It’s a remarkably simple radio, with only 4 buttons, a volume wheel and a tuning wheel, but it is an 11 band radio, clock, alarm, calendar and MP3 player. The radio uses 2 AA batteries, has an earphone jack and a jack for an external 3V power supply. The antenna extends to 17.5″ and swivels allowing it to be vertical when the radio is on its kickstand, a fob on the end of the carrying strap.

It has AM (MW), FM, FM1 (70-88 MHz) and 8 shortwave bands from 5.95 – 21.85 MHz. The chart later on shows discrete ranges for the bands, but in practice, there are no gaps between bands; coverage is continuous. Tuning is digital. Repeatedly pressing the FM button switches between the FM and FM1 band. Repeatedly pressing the SW button sets the tuning to the start the next shortwave band.

Inserting a MicroSD/TF card in the slot in the side converts it to an MP3 player. The same 3 radio operation buttons work as MP3 player controls, with function labels on the top of the radio.

This description was found on the internet, translated by Google from simplified Chinese [page no longer available]:

The performance improvement brought by DSP technology to this radio section product: digital filtering, strong selectivity, no tandem; full-band frequency tracking and locking technology, no image and frequency drift phenomenon in short-wave reception; digital processing technology makes the sensitivity comprehensively improved, There are many receiving stations; built-in digital power amplifier, high power, low distortion; FM stereo output.

Also at the same site these specifications:

1. Frequency coverage
   FM: 87 -1 -108 +1 MHz 
   MW : 520 -60 – 1710 +60 kHz
   SW1: 5.95 – 6.20MHz 
   SW2: 7.10 – 7.30MHz 
   SW3: 9.50 – 9.90MHz 
   SW4: 11.65 – 12.05MHz 
   SW5: 13.60 – 13.80MHz
   SW6: 15.10 – 15.60MHz 
   SW7: 17.50 – 17.90MHz ( Shortwave frequency coverage is not narrower than the above requirements ) 
2. Noise limiting sensitivity 
   FM : 30 Noise Limit Sensitivity 10 dBu 
   MW : 26 Noise Limit Sensitivity 70 dBu 
   SW : 26 Noise Limit Sensitivity 35 dBu 
3. Signal-to-Noise Ratio 
   FM: 98 MHz    ≥ 50 dB 
   AM : 1000 kHz  ≥ 40 dB 
4. Selective MW: 1000 kHz   +/- 9 kHz  ≥ 40 dB 
5. FM stereo separation: ≥25 dB 
6. Maximum current consumption: ≤ 180 mA 
7. Maximum output power: ≥100 mW, maximum distortion ≤ 20 % 
8. Size: 124*77*21mm

A brief test using just the whip antenna picked up many stations on shortwave. Here’s Radio Romania International on 7420 kHz on June 5 at 0010 UTC heard in central Virginia.

Controls

The functions of the 4 buttons were easy to discover. There are basically 3 sets of functions, when the radio is off (clock, calendar, alarm functions with dates and times selected with the tuning wheel), when the radio is on (band selection), and when the radio is on and a micro SC/TF card is inserted (next track, play/pause, previous track). Counterclockwise rotation of the tuning knob increases frequency.

Setting the clock/calendar/alarm

Settings are accomplished with the radio off. A quick press of the MW button turns the alarm on and off.

To set the clock:

1. Turn the Alarm off (MW button)
2. Short press the FM button to enter time setting mode
3. Rotate the Tuning knob to set the hour
4. Short press FM and rotate the Tuning knob to set the minute
5. Short press FM and rotate the Tuning knob to set the year
6. Short press FM and rotate the Tuning knob to set the month
7. Short press FM and rotate the Tuning Knob to set the day
8. Short press FM to exit setting mode and start the clock.
9. The Week number is set automatically

To set the alarm:

1. Turn the Alarm on (MW button)
2. Short press the FM button to enter alarm setting mode
3. Rotate the Tuning knob to set the alarm hour
4. Short press FM and rotate the Tuning knob to set the alarm minute
5. Short press FM to exit alarm setting mode

Sleep timer

With the Radio on or off, long press the Power button until 90 is displayed on the screen. That indicates a sleep time of 90 minutes before the radio automatically turns off. Repeatedly press Power to decrease the time in 10-minute increments, or until “On” is displayed, indicating that the sleep timer is disabled.

Features

The small speaker does not produce rich sound on radio, nor is there any significant bass response even with good earphones. Sound is much better playing MP3 files.

The display is large and easy to read. In radio mode, the band is displayed along with the time and frequency. There is also a stereo indicator for FM. When the radio is first turned on, a button is pressed, or the tuning wheel turned, the display is illuminated with a pleasant amber glow. When the radio is off the radio displays the date and time. In MP3 mode, the radio displays the time of day, the track number and the elapsed time played in the current recording. It does not play files in the WMA format.

My only puzzle is how (if possible) to set the AM tuning step to 10 kHz instead of 9. I’ve found virtually nothing about this radio on the internet. I probably bought it on eBay a dozen years ago.