Path: ...!3.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Don Y Newsgroups: sci.electronics.design Subject: Re: AM radio law opposed by tech and auto industries is close to passing Date: Sat, 4 May 2024 14:55:46 -0700 Organization: A noiseless patient Spider Lines: 37 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 04 May 2024 23:55:58 +0200 (CEST) Injection-Info: dont-email.me; posting-host="c5cd803a4c971ac4458aa4d6c475c735"; logging-data="1505046"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18YIsfDvQ7wz/VriBO1xlMb" User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Cancel-Lock: sha1:1RTcMTdK2BvdBViTXq19BE95cGg= Content-Language: en-US In-Reply-To: Bytes: 2932 On 5/4/2024 1:29 PM, Carlos E.R. wrote: >>>> AM radio can be leveraged for wide area coverage without requiring >>>> lots of other technology to keep it operational.  And, the receivers >>>> can run for long periods of time on batteries (that are likely >>>> stale) or clock-spring mechanisms (emergency radios). >>> >>> I have seen radios with a hand spun dynamo. >> >> I have one with a clockwork mechanism -- wind up a large spring and >> it drives a small "generator" as it unwinds.  It takes about 5 minutes >> to unwind completely so it's a relatively low "winding" duty cycle. >> >> But, it is large-ish. >> >> It also has solar cells and a small, internal battery (which is toast; >> but, attempting to disassemble it to replace the battery would likely >> result in a mess of gears and torsion spring parts!)  As the spring mechanism >> will run the radio despite the bad battery, it seems a safer plan to just >> tolerate the bad battery! > > That's a bad design, that the battery of such a thing can not be replaced > "easily". I suspect it is a rechargeable cell that the designers thought would "never" need to be replaced. The fact that it works *despite* the state of the cell suggests SOME forethought was put into the design. The mechanism being able to release enough mechanical energy to the generator over such a long period of time without relying on the instantaneous energy created by hand-cranking a generator and storing it *in* that cell. (This is how many "emergency flashlights" work -- and FAIL to work, over time; relying on the cell to remain functional!)