Difference between revisions of "Colpitts Crystal Oscillator"

From Land Boards Wiki
Jump to navigation Jump to search
Line 12: Line 12:
 
* Design from [https://www.amazon.com/Experimental-Methods-Design-ARRL-Inc/dp/087259923X Experimental Methods in RF Design]
 
* Design from [https://www.amazon.com/Experimental-Methods-Design-ARRL-Inc/dp/087259923X Experimental Methods in RF Design]
 
** Built by others (W2AEW, IMSAIGuy, etc)
 
** Built by others (W2AEW, IMSAIGuy, etc)
* Runs from 7V to 16V (may go higher, didn't tempt fate
+
* Runs from <5V to >16V
 +
** May go higher, didn't tempt fate
 
* 15mA with 4.44 MHz crystal at 12V
 
* 15mA with 4.44 MHz crystal at 12V
  

Revision as of 19:55, 20 August 2021

Colpitts Osc P1780-720px.jpg

Features

  • Colpitts Crystal Oscillator
  • Junkbox parts
    • (2) 2N3904 transistors
    • Standard value 1/4W resistors
  • Useful for binning crystals
  • Design from Experimental Methods in RF Design
    • Built by others (W2AEW, IMSAIGuy, etc)
  • Runs from <5V to >16V
    • May go higher, didn't tempt fate
  • 15mA with 4.44 MHz crystal at 12V

Prototype

  • Cut square PCB material for raised pads
  • Build on single side Copper clad PCB material
  • Large ground plane

XTAL-Osc-5-720px.jpg

Prototype Scope Caps

  • UUT = 4.4433 MHz crystal
  • Rigol DS1054Z - 59 MHz scope (100 MHz mod)
  • UltraScope
  • 8 Digits Frequency Counter shows 4.432298 MHz
  • Waveform triangular

XTAL-Osc-UltraScope-01.PNG

  • FFT
  • 0-50 MHz
  • Shows lots of extra noise
    • In plastic box

XTAL-Osc-FFT-01.PNG

  • Fundamental - zoomed in

XTAL-Osc-FFT-03-Findamental.PNG

  • FFT 3rd harmonic
    • 3rd harmonic down about 20 dB

XTAL-Osc-FFT-02-3rdHarmonic.PNG

W2AEW Video

  • Wes Haywood EMIRFD cirvuit

XTAL-Osc.PNG

XTAL-Osc-2.PNG

XTAL-Osc-3.PNG

PCB

CP-OSC-3D-3.png

Assembly Sheet

Colpitts XTAL Oscillator Rev 1 Assembly Sheet