I continue to be intrigued by the tiny DSP radio from Kchibo, the KK-D202. That’s the radio that I’m most likely to slip in my shirt pocked when walking out the door. This KK-D680 from Kchibo fits in a shirt pocket too, though not quite as comfortably at one inch thick. The covers are different, but there is a lot similarity under the hood between these two radios.
Both radios have Chinese labeling and manuals and are similar in many other respects. I found by disassembly that the KK-D202 used the si4734 digital signal processing chip from Silicon Laboratories, and I am assuming this new radio uses the same based on similarities in operation.
I had two big gripes with the KK-D202: an unlighted display, and sucky AM performance. My first grievance has been totally removed in the KK-D680. It has a large bright orange display that automatically activates when the radio controls are used. AM radio performance has improved, but it’s not all that great. One nice feature of the si4734 radios is the option for a signal strength display. This makes it possible to make a quantitative comparison between radios that use the chip, in my case the Kchibo KK-D202, the Kchibo KK-D680 and the popular Tecsun PL-380. I’ll use that feature in the performance tests below.
A lesser gripe involved tuning. On the KK-D202 tuning was accomplished by up and down buttons that served also as scanning buttons when held down. The KK-D680 adds a real tuning knob, so instead of pressing buttons like forever, you can turn the wheel like forever. However, the new tuning knob comes at the price of a volume control knob not present on the KK-D680. Otherwise the controls are almost identical in function to the KK-D202 even to the magic sequence of the Memory button to switch from 9 kHz to 10 kHz stepping on the AM band. Refer to my article on the KK-D202 for an operations manual for the radio.
The buttons under the digital display are, from right to left: Memory [alarm on / off], Set preset memory +, Set preset memory – and Band Switch [Enable time/alarm set]. The buttons on the right are, from top to bottom: Power [sleep timer], Volume +, Volume – , Tune up [time +] and Tune down [time –]. There is also a tiny reset button upper right.
The radio comes with a carrying strap, plush carrying pouch, ear buds, Chinese manual and external antenna. Mine came from DinoDirect for $22.95 with free shipping, but doesn’t seem to be on their web site any more. [As of today, 1/17/2012, eBay seller DPmega has an “upgrade” version of the radio for sale for $29.90 with $12 shipping. The upgrade version has a 9/10 kHz step setting that’s documented (probably a switch in the battery compartment).]
Since a good bit has been written about the Tecsun PL-380 DSP receiver, I’ll use that as the reference radio for these tests. The value listed is the signal strength followed by the S/N ratio as measured by the DSP chip. (Note that the Kchibo radios display these in reverse order from the Tecsun.)
|Test||Tecsun PL-380||Kchibo KK-D680||Kchibo KK-D202|
|FM 88.7 MHz dBμ / dB||34 / 21||31 / 22||31 / 21|
|SW 10 MHz||15 / 2||9 / 2||9 / 0|
|AM 660 kHz (strong local station)||50 / 25||49 / 25||40 / 25|
Those numbers don’t reflect the experience of listening. Generally the Tecsun was noticeably better in all cases, followed by the KK-D680 and the KK-D202. Even on the local powerhouse AM station, there was a little hiss on the Kchibo radios that was absent with the Tecsun.
|Frequency coverage||FM 64 – 108 MHz AM 522 – 1710 KHz (9 KHz step) AM 520 – 1710 KHz (10 KHz step) SW 2.3 – 21.85 MHz|
|FM Stereo||Yes (earphones)|
|Memories||3 x 30|
|Sensitivity||FM 3.5 μV AM 3 mV/m SW 32 μV|
|Selectivity||>= 40 dB|
|External DC||3v Center (-)|
|External antenna jack||No|
|Tuning||Digital (up/down, memory, scan), knob|
|Tuning step||AM 9/10KHz, FM .1 MHz, SW 5 KHz|
|Signal strength indicator||Yes|
|Whip antenna length||17 3/4”|
|Clock||Day, Date, Time, Alarm, Sleep|
|Attached battery door||No|
|Size||4 3/4” x 3” x 1”|
|Weight without batteries||4 3/4 oz.|
|Accessories included||Ear buds, external antenna, pouch|
|Price (including shipping)||$22.95|