[Amps] power supply transformer

[kg7hf at comcast.net]

Hi Manfred,

My original thoughts were not to use a transformer, I had never seen a 'real' design, besides a switched mode power supply that did not have an isolation transformer on the mains before actual discreet components, but non the less, since I needed ~100 volts, I thought to just rectify and filter directly the AC mains.

I still believe this is a viable solution, but as people suggest, certain precautions have to be made.  The things I like about it are less weight, less difficult to find components.  As far as technicians safety, well, you have to have a minimal understanding of what you are working on, and know where and where not to put your fingers.  This is true if your working on a solid state amp, a tube amp or an electric drill.  As long as it is safe with the cover on, that is the important thing!  My own expierence in the Navy as a communications ET drove that into me, working on URT-23B's ( twin 4CX1500A7 PA's), you could get a real bite from those!

I'm not sure that I understand what the input and output RF transformers have to do with providing insulation from the power supply.  Also, when you say that the "transistor-to-heatsink" also must comply with this, what does that mean exactly?  I think that of course these components should be insulated from the AC mains, it would not work correctly if they were not.  I'm sure it is my lack of understanding, but I'm completely not following you on this.

As far as winding my own, I thought of that option.   As I have expressed to others privately (now publicly), I don't have a feel for where to acquire parts quite yet.  My limited expierence usually take me to DigiKey or Jameco, but they are not good sources for these types of components.  

Although I was first licensed in 1982, I have not been an active operator for at least the last 14 years.  In fact, I about 4 months ago, was putting my remaining radio equipment up for sale on ebay when my 12 year old daughter started asking me questions about it...she's now KB1OGL, and we're putting together a new and improved station!

So, I welcome many many suggestions on where to buy components, mail order, etc, as I have nothing in my "junk box" anymore.

73's
Paul KG7HF