4.1.15

POOR MAN's TEST EQUIPMENT

Εδώ θα δείξω μερικά απλά και ταπεινά παλιά  όργανα του Χόμπυ των Ραδιοεπικοινωνιών.

GRID DIP METER MILLEN 90661
measuring instrument to measure resonant frequency of radio frequency circuits. It measures the amount of absorption of a high frequency inductively coupled magnetic field by nearby objects. It is an oscillator whose amplitude changes when near a resonant circuit which is tuned to the frequency the oscillator generates. At the heart of the instrument is a tunable LC circuit with a coil that serves as a loose inductive coupling to the measured LC resonant circuit. Resonance is indicated by a dip in the meter indicator on the device, usually based on a microammeter.
  Usually measure the properties of resonant circuits, filters, and antennas.














 adverdising  of the model 90662


video: how it works
https://www.youtube.com/watch?v=_pgQq9IxZy0

manual (90651 model):
http://www.k7jrl.com/pub/manuals/millen/90651/90651.pdf
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tube tester


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Transistor tester