Power Supply 30 Meter Amp

Step 1 - Building The Power Supply

The first thing I started with was build and test out the power supply. And the first item to check out was the transformer to make sure it would be capable of giving me the voltage's needed for this project. The transformer can be operated at 120/220 volts. I'm using 120 volts at this time as I have no 240 line at this time. This transformer has lot of secondary voltages. A 550volts tap, (4) 6.3 volt taps and (1) 105v tap. This transformer was taken from a discarded HP test equipment.

I spent about two days putting the rectifier board and the filter capacitor board together. I tested each board before connecting the two together, To be sure there were no problems. Its much easier to trouble shoot any problems before putting the two together.

The original circuit call for 1N3253 diodes in the rectifier board. I used 1N4007 diodes. It also call for 1200v .01uf ceramic disk capacitor. I used .01uf 2kv capacitor because that's what I had on hand which will also give it more head room. The filter capacitor board call for 40uf at 450volt. I used 40uf at 500 volt. It took a little time to fine these on ebay. I came across a ebay seller ((JustRadio)) that were selling different electronic components and they carried the 40uf capacitor I needed.

Both boards were built on perforated board. I used thin aluminum tubing and long treaded rods to make my standoff mounts for the rectifier and capacitor board.

After wiring both rectifier and filter capacitor board together another test was done to measure the output voltage. A high probe was made to allow me to test the high voltage supply. As you can see from picture to follow. You can see from the two different meters the voltage test are the same. Voltage measure 1650vdc with 122-125 vac line input. The meter show 1620vdc that was because I was able to control the input ac voltage with a homebrew varic supply. When connected directly to the ac line I measure 125vac with 1650vdc out.

The standoff were made from some small aluminum tubing I had on hand, and a small 3 foot treaded rod purchase from home depot with nut was used to mount the two board together. And some home made L bracket to attach the boards to the base plate. Not having to drill holes in sheet metal was great. Just screw everything right into the wooden base.

The rectifier board is made up with (6) .01uf ceramic disk capacitor, (6) Diodes, and two 5 watt 50 ohm sand type resistors.

The filter capacitor board was made with (4) 10 watt 25K ohm sand type resistors. and (4) 40uf 500 volt electrolytic capacitor. The 4 resistor are used as bleeder resistor to drain the electrolytic capacitor when the power is turn off.

This amplifier was constructed on some scrap 1/2 inch plywood board cut from an old shelf I made sometime ago.

Below you'll fine a image gallery of pictures of the power supply. Click on the thumb nail picture on the right to scroll through the pictures.

This is the HP transformer used for this project. It's was a pull from a non working HP test equipment that was given to me by a friend.

Here's a another view of this HP transformer.

Top view of rectifier board. Rectifier board is made up of (6) Diodes, (6) Ceramic Disk capacitor and two 5 watts 50 ohm resistors

Bottom view of rectifier board all wired up.

Here's a view of rectifier and cacaitor board mounted together.

Another view of rectifier and capacitor board mounted together.

A closer view rectifier and capacitor board mounted together

Top view of Filter Capacitor Board / made with 4 40uf 500vdc Electronlytic Capacitors. and 4 10 watt 25K Ohm sand type resistors

Bottom view of Filter Capacitor Board all wired up

Doing a high voltage test. I have 1,620VDC out of this power supply.

High voltage test using my home made high voltage probe, Measuring 1,620vdc.

Here's showing a high voltage test using my home made high voltage probe.