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9V AC power supply
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mtimmermans:
Inspired by Dave's video "EEVblog #801 - How To Design A Digital Clock", I am trying to also make a digital clock.

This probably sounds like a very stupid question, but for some reason it seems impossible to find a AC/AC European adapter which goes from 230V to 9/12V. Do they even exist? I found one on farnell (https://nl.farnell.com/ideal-power/77de-06-09/power-supply-ac-ac-10w-9v-0-67a/dp/2368012) which would be perfect, but unfortunately they only sell to companies. I also found one on jameco (https://www.jameco.com/z/GPU481202000WAOO-12V-AC-to-AC-Wall-Adapter-Power-Supply_2197581.html) but they don't sell the European variant.

Do I maybe use the wrong keywords for my searches? I have tried:
AC/AC transformer
AC/AC wall plug
9V AC adapter
9V AC power supply

A second option would be to use a PCB transformer, but I have seen that people generally advise against using these due to safety concerns.

Any suggestions?
Signal32:
I assume you want to build the mains-frequency-clocked transformer and don't want to use another solution for clocking (like c crystal).
Spain eBay then ?https://www.ebay.com/itm/ALIMENTADOR-DE-220VAC-A-9VAC-1000MA-50X43X62MM-JACK-HUECO-5-5X2X9-5MM-BD4674/362209595951

Personally I would get a regular AC-DC adapter, because of availability and just remove the AC->DC part after the transformer.
You can also keep that and add an extra wire directly from the transformer to your PCB that provides the clocking.
tooki:

--- Quote from: Signal32 on August 26, 2018, 10:56:03 pm ---Personally I would get a regular AC-DC adapter, because of availability and just remove the AC->DC part after the transformer.
You can also keep that and add an extra wire directly from the transformer to your PCB that provides the clocking.

--- End quote ---
Except that linear transformer-based AC-DC adapters aren't sold any more, because they don't meet the various requirements (EU, US Energy Star, etc) for standby power consumption. That's why they've all moved to being SMPS-based.

AC-AC adapters remain transformer-based because, well, there's no real alternative!
IanB:
I think you will find an AC wall plug adapter is difficult to obtain, mainly because very few items need one of these. However, a simple mains step down transformer should be easy to obtain. If you can't find a transformer by itself, try looking for a door bell transformer.
tooki:

--- Quote from: mtimmermans on August 26, 2018, 10:34:08 pm ---Inspired by Dave's video "EEVblog #801 - How To Design A Digital Clock", I am trying to also make a digital clock.

This probably sounds like a very stupid question, but for some reason it seems impossible to find a AC/AC European adapter which goes from 230V to 9/12V. Do they even exist? I found one on farnell (https://nl.farnell.com/ideal-power/77de-06-09/power-supply-ac-ac-10w-9v-0-67a/dp/2368012) which would be perfect, but unfortunately they only sell to companies. I also found one on jameco (https://www.jameco.com/z/GPU481202000WAOO-12V-AC-to-AC-Wall-Adapter-Power-Supply_2197581.html) but they don't sell the European variant.

Do I maybe use the wrong keywords for my searches? I have tried:
AC/AC transformer
AC/AC wall plug
9V AC adapter
9V AC power supply

A second option would be to use a PCB transformer, but I have seen that people generally advise against using these due to safety concerns.

Any suggestions?

--- End quote ---
Use an old-fashioned transformer with wires? Easy to work with, reasonably safe, and easy to get.
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