This item is retired. Please consider to buy newer version

https://www.tindie.com/products/microwavemont/am-sw-fm-radio-by-dsp-radio-chip-version-2/

or

https://www.tindie.com/products/microwavemont/dsp-radio-version-3/

For customers: Firmware is updated to activate amplifier inside DSP chip. The new firmware (dsp_radio_KT0915_3.ino) can be uploaded through USB-TTL interface via Arduino IDE (Please select Arduino Pro with ATmega328P/8MHz). The new firmware does full amplification and some external audio attenuator (simple variable resistor) is required for volume control but direct speaker driving is possible. Please try! and thank you for support.

As per request, two, YES!! just two kits are prepared on Aug.9th, 11AM JST(UTC+9). This is really the final (due to my OLED display stock ends) and Please don't miss it!!

What is it?

Several one-chip DSP radio is available on market. These chips realises very wide band receiver (generally AM(535-1620kHz)-SW(2MHz-30MHz)-FM(76-108MHz)) without any conventional inductor and resonator but single chip controlled by I2C. This kit provides a radio kit in 21st century!! It consists of KT0915 (DSP radio chip), ATmega328 (controller) and LiPo charging circuit. This kit is a "semi-kit", where ATMega328(radio firmware written), KT0915(Radio chip), TP4057(LiPo charging IC) are populated on board. The rest (chip 0603 C, R, LED) must be soldered for completion, meaning very good soldering skills are required. This product has ultra-limited number. The first lot is the last lot and if you have some interest, don't miss it!!

Why did you make it?

Even 21st century, some isolated country (speaking frankly,for example, North Korea) has only radio broadcast as a information media and shortwave radio reception is still interesting. Not only such a country, receiving direct information from overseas is a good fun before sleep at bed-side. Also FM broadcast reception plays a good BGM during work. But I have several complaint about Radio sold by big company. Recent radio (digital PLL) sometimes does not have "tuning dial" but simple 10-keyboard for frequency input but I want "tune" its frequency. Other complaint is, I don't know why, NO rechargeable battery equipped shortwave radio is sold by major company (just like SONY). I don't want to make "garbage" of used battery. So I made this one

What makes it special?

(1)Easy use, just one frequency tuning knob. Pushing tuning knob changes band from AM-SW-FM. (2)AM broadcast full cover from 500kHz to 30MHz and more. (3)FM board case full covered from 60MHz to 130MHz. (4)LiPo charging circuit on board. Just connecting LiPo battery (NOT included in kit. Please buy from your local battery reseller) and recharge by USB cabe.

What included in this kit: (1)small ferrite bar antenna for AM(520-1620) reception (2)PCB: already firmware-written ATMega328, DSP Radio chip(KT0915), TP4057(LiPo charging chip) and tiny OLED display are mounted. (3)R, C, and chip LED (4)USB connector, battery connector, 6-pin socket for FTDI adaptor(if you want to re-write your firmware) (5)Rotary encoder and knob.

What NOT included (A) LiPo battery. Please find it at your local reseller. When its population, please be careful of its polarity. (B) Antenna, just thin 2-30 cm wire will be enough for FM reception. Longer antenna will be good for shortwave.

CAUTION about this kit: For radio operation, LiPo is indispensable. Please obtain LiPo battery even for initial test. Short-time check can be 1.5V battery x 2 = 3.0V connecting to on-board LiPo terminal but this case never connect USB cable (otherwise 1.5V battery suffers from charging current, it is quite dangerous)