Whats this high frequency audible tone coming off my C8?

2 posts / 0 new
Last post
RWS34
Offline
Last seen: 1 week 11 hours ago
Joined: 09/29/2013 - 21:48
Posts: 33
Whats this high frequency audible tone coming off my C8?

I’ve been relying on the C8 for about 4 years in my home inspection business. First one was off ebay (playing the Chinese lottery as they say), and it was a good one. All subsequent C8s were Convoys from Fastech.

When I shine the C8 at sheetmetal or brick at close distance (less than a foot), its real easy to induce a clearly audible, high pitched tone…right about 4,450 Hz. It works with any of my C8s. What causes this sound? Makes me wonder if the flashlight is outputting something more than just visible light.

I played with a simple online test tone generator to get an approximate number in Hz for the frequency. here’s the link, it should be preset to 4,450 Hz. I’ll bet you’ve heard/noticed that sound too. Thanks in advance.

http://szynalski.com/tone#4450,v0.75

Edited by: RWS34 on 10/08/2018 - 20:11
Tom Tom
Offline
Last seen: 2 hours 19 min ago
Joined: 09/10/2017 - 08:30
Posts: 804