4-1000 project complete and a success!

Well I'm not sure if this project will ever be really complete.  However first transmissions using this little homebrew amp have been a major success.  Without pushing it hard,  the amp will make about 1200 watts output power on SSB,  with 100watts input.
On AM I am driving it with about 15-20 watts input.  This gives me 200watts dead carrier and peaks of around 600 watts on modulation.
The parameters are:
Grid current 30 milliamps
Plate current 200 milliamps
Plate voltage  4000 volts

If any questions,  feel free to email me at ND4JS@arrl.net

I am planning on drawing up schematics of the amplifier and they will be poster here soon.
ND4jS    J

Adding case sides

New and Improved Bridge Rectifier

Here is the new and improved bridge rectifier.  Using 40 diodes, .01 caps and 68k  resistors across each diode for voltage equalization,  I also installed the blowers to pressurize the chassis.

Double blowers

T/R Relay and High Voltage Test Today

Was successful today in hooking up the T/R relay.  Also wired the high voltage into the RF deck.  Brought the amp up with 3000volts dc applied to the plate.   Not smoke or sparks!
Successful first test.  Next test will be with adding some RF.


                                       T/R  Relay setup

Under side of Chassis 

Rear of RF deck

Getting things put together

I had a chance to do some work on the amplifier this afternoon.  I got the filament transformer hooked up.  Also wired a 12v dc power supply for the relays.
Wired all the AC and relays.
Below are pictures of what it looks like now.


12 v dc power supply for relays

  Fuse block

High voltage relay

Back of RF deck

  

          Now she glows!!!

                                                           

            Filament Transformer

Major Setback Today

Well, major setback today.  I began to mount the power supply equipment.  As you can see in the pictures below,  I mounted the high voltage transformer,  variac,  caps,  resisters, and rectifier.  There is no room for the filament transformer.  The next shelf up has to hold the RF deck.

 

 

 WEll, Back to the Drawing Board  :-)

4/14/2012

Today I built the bridge rectifier circuit for the amplifier.

I decided to string 10 6A 1000PIV diodes together on each leg of the bridge.  I discovered, that even though they are rated 1000volts they only really handle 700 volts RMS.  So allowing for the possibility of more than 5000volts I used 10 in a string for 7000 volts RMS.

Below is a picture.  Not pretty, but it worked,

So, the next step is to test the circuit.  I took it out to the workshop where the PolePig transformer and Caps are.

The guy that sold me the Polepig said that he had operated it on 220v.  I decided to bring it up slowly on a variac at only 110v.

Much to my shock,  on 110v in I was getting 5000v out. WOW.  The rectifier was working and I used a Bachman high voltage probe with my fluke multimeter to measure the voltage.

Next I decided to try putting the voltage into the two 8mfd 4000 volt oil filled capacitors.

The caps charged up to 5000v and then I realized I did not put bleeder resistors on them.  I had to discharge them the hard way with a long screw driver.  Pow!

So now I know that the power supply is going to work,  I need to begin assembling it.