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Techniques... Making a Dual Supply from a Single Supply

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Wikipedia says it's a commune.
Alberobello - Wikipedia, the free encyclopedia

I know Italy isn't the most democratic country in Europe but I didn't know that part of it is communist, no wonder you left.:eek:

Back on topic: if you have an AC supply and need a small low powered negative rail, then you could add a negative voltage doubler.
 
Oh didn't know that, my mistake, I've always associated the word commune with socialism. Hippies used to live in them in the 60s and China used to have them under Mao. :D

Yes, you can get a dual supply from a single transformer using two half wave rectifiers but it's only recommended at low powers. If you need a large current from the + rail and a small current from the - rail, it's normally better to use a negative voltage doubler.

Here's an example of using a negative voltage doubler to derive a low powered negative rail for biasing the ADJ pin of an LM317 at -1.25V so the output goes down to 0V.
 
Oh didn't know that, my mistake, I've always associated the word commune with socialism. Hippies used to live in them in the 60s and China used to have them under Mao. :D

well as it happens the local council party is the closest to comunists you would get or in any case a bunch of crooks, they "loose" records that you paid your council tax so unless you can prove you paid they charge you again knowing you already paid, after all if they lost the records they much have had the records to say you paid. 90% of those pulled up had to pay their council tax twice !
 
Are you talking about Italy or Northants council? You could be talking about either by the sounds of it. :D

well in this case italy, northants (wellingborough) are even better you make a direct debit agreement with them and then get a letter informing you that they going to charge you the whole lot in a few days time, cheeky buggers, I went down the council to here many others with the same problem. all i hear here is "making wellinborough a place to be proud of" yea ? really ? I'd personally run this council out of town with glee. I eventually argued my arangement down to £ 10 a month and the rest to deal with in april as I was practically out of a job then. now i'm working again full time they can still wait. whats good for the goose is good for the gander ! unfortunately in Italy you are powerless.
 
Why don't you get a credit card like everyone else?

erm now that I am in the UK I do have 2 debit cards and do buy online, my earlier comments were made when I lived in italy and no you can't get l such things as credit cards so easily out there and a good job too (wonder why the UK is the worst hit by the credit crunch). I did have some sort of debit card thing in Italy but many sites would not accept it and many more companies like RS expect you to be a business to buy from them. in case I haven't already said: life was different in italy
 
I don't have a credit card at the moment. I use a debit card for all my online shopping. I'm thinking about getting a credit card because it offers you more protection if the company you buy stuff from goes bankrupt before you get your goods.
 
I use the credit card of a major grocery store. Any purchase gets points that are redeemed for food.
I use the credit card of a gasoline company for buying gasoline. It gives a price reduction plus points that can be redeemed for gasoline.
 
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