The ebay 10$ solar powered flashlight FM radio and mobile phone charger ebay item 370856410707
formatting link
This is my second option to put the Geiger counter in. the thing arrived late this night, curiosity opened it:
formatting link
nice screws..
No headphone jack, but a real very loud speaker:
formatting link
also note the nice Lipo battery, estimated at 600 mAh, enough to power geiger for days... Now this mysterious chip, same probably as in the 2$69 FM radio, well, here it is no longer hidden:
formatting link
It is a HXL1618.
Some ebay search for the datasheet find this in Chinese, but the circuit diagram speaks universal language:
formatting link
site takes a long time to load, but scroll down to page 3 or 4 for that circuit diagram, the RST and UP button confirm it is the right chip. Seems the Chinese are ahead again... they are inventive. Only drawback with this tuning system is if your station had fading it will skip to the next station, and that most likely is not your favorite one, bit annoying. Datasheet says chip is made by HONGCHENGWEI ELCETRIC CO., Ltd, should that be Chinese for ELECTRIC?
There are some more chips, likely for the charger and LED driver.
Solar cell and 4 bright white LEDs shining:
formatting link
I like this thing very much actually, it misses a headphone jack, but comes with all sorts of USB to DC plug adaptors.
So far the best candidate to put my counter in, OLED or LCD display can go on the back.
I tell you, an empty plastic box of this size here plus local shipping costs more.