Hello from Hong Kong

Hello from HK 22°20'17.5"N 114°13'11.3"E

I am using a DIY Geiger Counter, with an j408γ Tube.
Conversion factor: 0.0015798

Hello and welcome to Radmon. I am also relatively new here, but i have to ask if your counter is actually clicking at around 3 times per second (180 CPM). Most sea-level counters are closer to 20 CPM, and I'm pretty sure that the other HK detector near yours (radiation@home user philip-in-hongkong) is not functioning correctly. (He has not replied to queries from that site's members or admin). I also know because I carried a geiger counter to Hong Kong in the early '90s. Levels like yours are typical of flying at 25,000 feet altitude.

I aslo don't believe the reading at first time, untill I find a news in a website (link).(the blockground value of my counter measuring is around 0.24~0.3uSv/h)

Hi k210ing:
It looks like your sensor is working normally now. Congratulations.

Welcome to the site and system