Difference between revisions of "Frequency Counter"

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== Rework - Add Pre-Amp ==
 
== Rework - Add Pre-Amp ==
  
* Uses extra transistor that would have been used by crystal tester oscillator
+
* Re-uses extra HF transistor that would have been used by crystal tester oscillator
 
* Based on  
 
* Based on  
  

Revision as of 12:39, 3 October 2020

FreqXounter-Kit-Assembled-02.PNG

Features

Case

  • P-Touch white on black labels

FreqCounterLabels.jpg

  • Inexpensive plastic case
    • Plastic Waterproof Cover Electronic Project Instrument Enclosure DIY Box Case Junction Box Housing 100 x 60 x 25 mm Black
  • BNC connector - female chassis mount
  • 5.1mm Chassis mount power connector
    • 7-9V in

Rework - Add Pre-Amp

  • Re-uses extra HF transistor that would have been used by crystal tester oscillator
  • Based on

Pre-Amp schematic

FreqCounter PreAmp Schematic.PNG

When building kit, do not install

FreqCounter DoNotInstallParts.PNG

Cuts/Jumpers

  • Front side cuts - blue
  • Jumpers Red

FreqCounter Rework PCB Front.PNG

  • Back side cuts

FreqCounter Rework PCB Back.png

FreqCounter Rework-Cuts-Back.PNG

  • Details of preamp input pin

FreqCounter Rework-06.PNG

  • With parts

FreqCounter Rework-07.PNG

Testing

FreqCounter InCase.jpg

  • 4.9152 MHz crystal
  • Scope frequency counter shows 4.19520 MHz
  • Freq Counter displays 4.9747 MHz
  • Difference = 500 Hz or 0.1% accuracy
  • Can only adjust the variable capacitor in narrow range

Reviews / Builds