亲，買黎試下

Use this...

#18

A woodpecker would be the best but you have to feed it. No battery required.

!

無線門鈴

just coil and magnet only, no magic，有位置最好買發射器比較大果款，個信號會強d



最後修改時間: 2018-01-13 22:01:07

What is the mechanism behind? Doesn't the powered side keep inducing current on the switch remotely via EM wave? Is it safe for human in such prolonged EM radiation exposure?


"用你按制嗰下嘅力量去產生少量能源", is it feasible?

最後修改時間: 2018-01-13 21:47:04

用你按制嗰下嘅力量去產生少量能源，用來發射一些訊號就可以。

PM了給你。

那處有得買？

鴨記五金店

唔洗再煩粒12V電仔
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網上有燒屋 clip, 話 12v 會意外自行著火



sorry, 似乎係流料

https://www.snopes.com/horrors/techno/9voltfires.asp
A new e-mail rumor indicates that 9 volt batteries may cause a fire if short circuited. This seems plausible, except: I short circuited 2 batteries (fully charged), together, (minus to plus and plus to minus, simultaneously) and the batteries demonstrated a temperature rise barely sufficient to detect with the bare finger, let alone cause a fire.

Likewise, making a “loose” connection to cause a spark is nearly impossible.

I suspect this is someone’s “worry” rather than an actual fact.

My question is: Is there enough energy in a 9-volt battery to start a fire? If so, how?

[Collected via e-mail, January 2015]

最後修改時間: 2018-01-13 16:35:11

我套落後了
按掣用 AAA，鈴聲插 220v

那處有得買？

小弟也剛自行DIY裝了一套，室外按掣不用電，室內鈴聲插220v。響鬧時間長短和音樂都可選，滿意使用中。

係無線發射器唔洗入電，接收器(bell)就插AC，有成幾十首音樂鈴聲

只係個press button唔駛用電，個bell 仍然要用電。

唔使電？輻射咪好勁？
.........
只係唔用乾電池。

我近期換左一套, 原先係 bell 用 12v, press button 用 AA or AAA?

新的一套係 bell 插濕電 mains socket
press button 用 AAA

唔使電？輻射咪好勁？