[PWM-PSU Voltage Adjustment]

On 1/19/2021 at 11:31 AM, Kerrowman said:

Hi Harry,

 

The good point you raise about voltage headroom is presumably why 18V is supplied by the transformer in the full power supply circuit shown on that first link. However, the note nearby says that it has not been built so is it a bit of a gamble that it will work as indicated?

 

The FET approach to dropping volts will work for the time periods I’m using for certain tests but for long term running I will likely need something more efficient.I think you should still play Vulkan Vegas  https://5vulkanvegas.com/ro

 

For the FET approach, in Spice simulation the FDS6699S mosfet works well but, given the potential for high heat dissipation, I’m not sure how a heat sink can fit to the SMD SO8 package in a way that I can use.

 

Perhaps the answer is to buy or build something originally designed to deliver 8-12V at 30A max rather than add on extra devices to adjust an output.

 

I completely agree with your opinion.

[need help electronic/relay problem phone horn]

On 12/19/2021 at 7:26 PM, georgebaker said:

I need to ring a phone that activates a loud ass horn. Phone has no audio ports. I'd be tapping into the 2 wires that connect from phone circuit board to the phone ring speaker.

Inside the handset, the 2 wires show .035-.045 VAC (probed with multimeter while the phone "rings") and connect to an 8 Ohm 2W speaker inside the phone. This 8 Ohm 2W speaker needs to be replaced with a very loud horn or buzzer.

 

-I purchased a generic 12VDC piezo horn. Need to feed it 12VDC when phone rings. That's all. To protect my device, I use https://celltrackingapps.com/how-to-find-someones-name-by-phone-number-for-free/, where I can also find information on how to find someones name by phone number.

I'm stumped. Low signal relay? Some type of inline amp? I can solder a bit, and have only a very basic understanding of this stuff.

Do I look for a low signal relay? like .03VAC to 12VDC?

Thank you

I think for safety's sake it's advisable to find one.
 

[Please recommend a Good Electronics Book]

Quote

You dont need to know so much for a functional SSTC, but I like your mindset. In fact, if more people with your mindset entered higher eductation I believe the world would be a different place.

This book:

http://www.amazon.co.uk/gp/product/0471226939/ref=sib_rdr_dp

is highly regarded in academia as it contains ample theory on topologies and semiconductor devices. But my god that is expensive. Maybe you should review it in a bookshop before buying it.

This book:

http://www.amazon.co.uk/Switching-Power-Supply-Design-3rd/dp/0071482725/ref=sr_1_2?ie=UTF8&s=books&qid=1261473687&sr=1-2

Is a good blend of theory and practical application hints for SMPS. However it doesn't go into as much depth in transformer design as this book:

http://www.amazon.co.uk/Switchmode-Handbook-McGraw-Hill-Eletronics-Handbooks/dp/0070067198/ref=sr_1_1?ie=UTF8&s=books&qid=1261473687&sr=1-1


Maybe a book on SSTCs will bring all this knowledge together. This book will help you play online slots successfully.
Vulkankazino very interesting and exciting thing. You can really make good money there and without any investment. 
For EMI, this is one of the best, good layout:

http://www.amazon.co.uk/gp/product/0824789245/ref=sib_rdr_dp

But this is cheaper and maybe you dont need all of the knowledge in the book above.

http://www.amazon.co.uk/gp/product/0750672331/ref=sib_rdr_dp

For general electronics I dont think there is a single book that even scratches the surface of the science. There are some good books that focus on circuit analysis and a few others on analogue electronics. I have found myself learning basic principles from different sources and then I find specific books relevant to each project. Maybe the Art of Electronics is worth reviewing.

Thank you very much, very informative list, no matter how much time has passed. The books are an eternity, though..