Generating "click sounds" for a geiger counter  - Page 1
Forum section: electronics / projects

author: PeterFW
author_rank: Frequent Contributor
timestamp: May 21, 2016, 04:54:03 pm
content: Hello!Bare with me, this is a stupid question.The obvious answer is, use short modulated pulses and a regular transducer.And, that is indeed what im dooing.But that does not tickle the 10 year old in me, who would like the thing to sound like the cool gadgets you see in the movies.These "chirps" just do not sound right.How could i create nice and, more important, loud "click" for my small and battery driven geiger counter?I do not have much space left in the case, size is a concern.The signal is provided by a microcontroller.Small electromechanical SMD transducers are not loud enough. Driven outside their rating they get to a decent SPL but that will only work with low CPM, otherwise they will burn out.A *big* piezo disc, driven through a h-bridge and enough voltage will work too but requires a lot of circuitry, a push-pull driver works too but is not as loud. At least that is what my tests showed.A cheap speaker requires a sealed enclosure and is fairly big, but it does produce a nice soundThere can not be much left, anybody else got an idea?Greetings,Peter

author: Fungus
author_rank: Super Contributor
timestamp: May 21, 2016, 05:10:16 pm
content: Quote from: PeterFW on May 21, 2016, 04:54:03 pmI'm sure there's a a double-meaning in there somewhere.Quote from: PeterFW on May 21, 2016, 04:54:03 pmTablet speakers? They're very thin and quite loud.http://www.ebay.com/sch/i.html?_sacat=0&_nkw=tablet+speaker+replacement&_frs=1You can also pull decent-but-small speakers out of old laptops. They generally come in sealed enclosures so they work in open air.I've got a collection of them somewhere from when somebody let me loose on a big pile of dead laptops for ten minutes (hint: grab the speakers and the batteries!)

author: Zero999
author_rank: Super Contributor
timestamp: May 21, 2016, 05:25:06 pm
content: What voltage are you using to power the transducer?A piezo disc driven from a small audio transformer.http://www.jaycar.com.au/Power-Products-Electrical/Power-Conversion-%26-Transformation/AC-AC-Transformers/500-ohm-Centre-Tapped---8-ohm-Miniature-Output-Transformer/p/MM2530

author: danadak
author_rank: Super Contributor
timestamp: May 21, 2016, 06:47:53 pm
content: One of the cheap UPs, in the 50 cent range, storing a sampled wave tableclick sound and fed to a DAC. Followed by a simple transistor amp should dothe trick.http://soundbible.com/tags-click.htmlhttp://www.partnersinrhyme.com/pir/PIRsfx.shtmlRegards, Dana.

author: m98
author_rank: Frequent Contributor
timestamp: May 21, 2016, 09:09:06 pm
content: The result of that project sounds pretty close:http://www.instructables.com/id/How-To-Make-A-Fake-Geiger-Counter/Quote from: Fungus on May 21, 2016, 05:10:16 pm

author: Raj
author_rank: Frequent Contributor
timestamp: May 22, 2016, 03:48:16 pm
content: micro driven 555 oscillator maybe?also i there is cmos machine gun sound generator, that could be tweaked for woodpecker like tweats-http://sbatangrokok.blogspot.in/2012/02/all-in-one-for-fun-circuit.html

author: FrankBuss
author_rank: Unknown
timestamp: May 22, 2016, 04:22:59 pm
content: Quote from: danadak on May 21, 2016, 06:47:53 pmWhy a wave table? Best sounding click (and similar to real Geiger counter events) should be aDirac pulse. You can use a pin of the microcontroller and a on/off transistor to power a speaker. Can't be short enough, but might need a few microseconds for the speaker coil, so one click = pin on, small delay, pin off.With the Audacity draw tool I created a click, an 44.1 kHz audio file of 1 s with one sample at maximum amplitude in the middle:http://www.frank-buss.de/tmp/click.wav