Toner resist on copper board

June 30 2015
Finally  received the 100 20Mhz crystals from Malaysia after a month wait at 9 cents a piece with shipping included.
         I begin the project by making a G0UUR board  for testing the crystal frequency  and make a list and choose close matched crystals. I needed 8 crystals  for the band past filter.

First test of the oscillator stability 

 



First test of the oscillator circuit on the etched PC board and found the oscillator level a bit low  and erratically  quit. It was caused by two voltage divider capacitors being too large a value  from the base to the emitter and ground . I changed the values from 1000pF to 220pF and then the circuit worked very stable and the frequency didn't drift.

Ready to tackle the 99 crystals ( short shipped one ) and write down the value and label the crystal.

Got about 75 done!

    Used Open Office Calculator to sort out the Khz descending values and found  eight  crystal that is 58 Hz in differences.  This should be okay to make the  20Mhz bandpass filter.

  Now I needed a test board to build the filter , the matching input attenuator and a load with an amplifier to monitor the output.
             I whipped up a pattern with ExpressPCB
software and ironed onto a pc clad  the toner.

                                                                                       a quick etch and the board is made.