QLS QA-660 comes with a standard PCB mount multi-secondaries transformer. This is probably not a bad transformer, but most of the time I would be more comfortable with a separate transformer for some application. We need 12V and 17V. The 12V is quite common, but 17V is rather tricky.

In the middle of the night few days ago, I decided to purchase some Talema transformers online. Luckily, the supplier got stock and I gave an early morning call to confirm. I got delivery by the afternoon. What a great and efficient process! I knew I wouldn’t be able to get 17V secondary, so I went with 18V. Hope they forgive me on this 😉

Quite tricky to get detail picture of some regulator. With the help of small mirror from my wife, I manage to shoot the picture on the mirror. Whoa, a 7805 regulator? I hope it’s for supplying power to display only.

Another tricky shot to capture 7808 regulator. Hmm….

With the help of my ‘macro’ lens, I manage to get the detail of this SMD type diode.

Push and pull between 317 and 337.

Basic structure of QLS QA-660 power supply. We have 3 rails, each with dedicated secondary. Need to trace a bit more to get deeper analysis.