# Change timing period to gadget ?

Aug 24, 2009
854
Hello.
My poor vision cannot reverse engineer now this $1 non-contact AC detector probe from Aliexpress. ----> https://www.aliexpress.com/item/3256804179002546.html?spm=a2g0o.productlist.0.0.b7a676aaPvFuj1&algo_pvid=333a1c52-53be-40e8-a0fc-24db71ce29a8&algo_exp_id=333a1c52-53be-40e8-a0fc-24db71ce29a8-22&pdp_ext_f={"sku_id":"12000028920452873"}&[email protected][email protected]!12000028920452873!sea It beeps like at 2Hz, would like to modify to 1 beep/chime every 60 seconds. Inside there is a 74HC14, a DC buzzer, bunch of dividing? resistors and 2 AAA cells; cannot follow tiny traces to make its schematic :-( Any help will be appreciated. It works like the video in here if you want to see it ----> https://www.amazon.com/Mr-Electrica...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ== (Ignore its flashlight feature) Last edited: #### Martaine2005 May 12, 2015 4,402 Hiya, Look up bigClive on YouTube, he did a few videos and reverse engineered several of these non contact pen types. I just looked and found one but it wasn’t your type. Go through his videos and have a look. He definitely has a couple of vids. Martin #### John Canon Jun 1, 2022 81 The beeper sounds so happy. Why do you want to make it sound sad ? #### CircutScoper Mar 29, 2022 300 Hello. My poor vision cannot reverse engineer now this$1 non-contact AC detector probe from Aliexpress.
----> https://www.aliexpress.com/item/3256804179002546.html?spm=a2g0o.productlist.0.0.b7a676aaPvFuj1&algo_pvid=333a1c52-53be-40e8-a0fc-24db71ce29a8&algo_exp_id=333a1c52-53be-40e8-a0fc-24db71ce29a8-22&pdp_ext_f={"sku_id":"12000028920452873"}&[email protected][email protected]!12000028920452873!sea

It beeps like at 2Hz, would like to modify to 1 beep/chime every 60 seconds. Inside there is a 74HC14, a DC buzzer, bunch of dividing? resistors and 2 AAA cells; cannot follow tiny traces to make its schematic :-( Any help will be appreciated.

It works like the video in here if you want to see it ----> https://www.amazon.com/Mr-Electrica...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

(Ignore its flashlight feature)

Well, you could take the "shotgun" approach and, since the beeping period is probably controlled by an RC timeconstant, increase all the capacitances by a factor of 120.

#### Externet

Aug 24, 2009
854
Thanks, fellows.
Found the exact item with the 74HC14 somewhere else, but still no schematic to attempt modify it properly.
---->

Found a schematic that claims done with a 4017 instead. It does not matter which chip, I could build it with such instead, am after only the 1 chirp per minute. How to modify still do not see it.

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