The Si483x is another of Silicon Labs' chips developed for consumer AM/SW and FM operation. This second generation mechanically-tuned digital CMOS AM/FM/SW radio receiver IC integrates the complete receiver function from antenna input to audio output into one chip, like the Tecsun PL-380's Si4734 digital chip did. The difference: this chip is analog-tuned.
Maximum band coverage of this chip is 504 KHz to 1750 KHz in the mediumwave band, 5.6 MHz to 22.0 MHz in the shortwave band, and 64 MHz to 109 MHz in the FM band. The 120, 90, and 60 meter tropical bands are not available. Neither is the longwave band.
AM sensitivity is comparable to the Si4734 chip, at 30µV input for 26dB (S+N)/N (signal plus noise to noise). The PL-380's Si4734 chip had a typical 25µV (S+N)/N sensitivity.
As an added bonus, use of a mechanical resistive tuning pot allows the frequency to be displayed in a linear format on the dial, so frequencies at the high end of the band are not crammed together as with capacitive tuning. It should make tuning a lot easier.
The Radio Shack 12-586 AM/FM Pocket Radio also uses this same chip and has had some positive reviews in the press. Reports are that AM sensitivity is good.
The '321 has been out of the gate for awhile, since about Fall 2011. I'll try to do a mini review soon. This being an analog-tuned chip, it will be interesting to compare real-world sensitivity and tuning differences between this and the Tecsun PL-380's digitally-tuned chip.
|Kaito KA321 AM/FM/SW DSP Receiver|