Path: ...!3.eu.feeder.erje.net!feeder.erje.net!usenet.goja.nl.eu.org!weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Bill Sloman Newsgroups: sci.electronics.design Subject: Re: CCFL transformer Date: Sun, 28 Apr 2024 14:19:50 +1000 Organization: A noiseless patient Spider Lines: 50 Message-ID: References: <66rk2jl35lbgd2tnqc6jjoqsd70ig9d485@4ax.com> <1cbq2j1168l9mpeefrghbcdtlt56131h1r@4ax.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Sun, 28 Apr 2024 06:19:54 +0200 (CEST) Injection-Info: dont-email.me; posting-host="01858230f45e989aa1d995adc277cfad"; logging-data="918474"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18huV+vKNNrwqWEfhxbW41qAqghcpEkQQ4=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:GgZPiUph/3pAYRjHaArdjf/20H0= Content-Language: en-US In-Reply-To: <1cbq2j1168l9mpeefrghbcdtlt56131h1r@4ax.com> Bytes: 3370 On 28/04/2024 3:17 am, legg wrote: > On Sat, 27 Apr 2024 01:26:09 +1000, Bill Sloman > On 27/04/2024 12:24 am, legg wrote: >>> On Fri, 26 Apr 2024 01:36:06 +1000, Bill Sloman wrote: >>>> On 26/04/2024 12:52 am, legg wrote: >>>>> On Wed, 24 Apr 2024 01:57:36 +0200, Klaus Vestergaard Kragelund wrote: >>>> There's a least one truly horrible 1969 text book on transformer design >>>> >>>> https://www.amazon.com.au/Soft-Ferrites-Applications-C-Snelling/dp/0408027606 >>>> >>>> and it took me years to realise quite how confusing it was. >>> >>> In my day, it was considered to be the bible, but I could never >>> afford a copy, so depended on photocopies and library access. >> >> I worked for EMI Central Research at time I thought that I needed it, so >> access wasn't a problem. The Seimens soft ferrite application notes >> turned out to be a great deal more useful, and much better organised. > > I believe it was Janson, Barrow and Burgum, with Jongsma at Philips > (Mullard), who reorganized Snelling's math into useful off-the-cuff > expressions in the mid 70s. . . using the Steinmetz coefficients etc. > > E.A.B. 32 through 34 are typical, if my records are accurate. Never got to see any of that. > > The Seimens catalog notes for use of power ferrite graphs 'sort of' > did the same, without actually explicitly stating ANY of them. > They were free and in book form. > > Anyways, high voltage applications are a different book. Why? The ferrites never get to see the high voltages. The windings do. When I was a graduate student I got to know a guy - Ales Strojnik - who had come from Slovenia to Melbourne to build a 600kV scanning transmission microscope,and immersed his winding in liquid transformer oil. Sulphur hexafluoride gas was more popular but made for a bulkier system. https://en.wikipedia.org/wiki/Ale%C5%A1_Strojnik He was rude about the French higher voltage version, which was huge. -- Bill Sloman, Sydney