Variable Capacitor

Discussion in 'The Projects Forum' started by crivoli, May 23, 2006.

  1. crivoli

    Thread Starter Member

    May 4, 2006
    26
    0
    Can someone please explain the leads of this variable capacitor and how to hook it up?
    I have never used one and I want to make sure I get this correct.



    Thanks
    -crivoli
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,584
    771
    This one is two variable capacitors in one package, connected in series with the G as the common point. you have to decide how big the maximal capacity should be. It can be 60,120 or 220pF.
     
  3. crivoli

    Thread Starter Member

    May 4, 2006
    26
    0

    Ok, thanks for the reply.

    So to create a variable capacitor from 0 to 160pf where would I run the wires?

    A wire from G to ground and a wire from O to the circuit?

    I'm sorry but I am still confused.

    Thanks
     
  4. Gadget

    Distinguished Member

    Jan 10, 2006
    613
    0
    G and A, but it wont get down to zero pF. Minimum is probably more like 10 to 15 pF.
     
  5. radiosmoke

    Member

    May 30, 2006
    17
    0
    -------------
    Very simple:
    this is a two section gang variable capacitor.
    That means that as the capacitor shaft is turned the capacitance increases or decreases depending on rotation.

    The leads are marked A for antenna and is 120 micro-farads
    G for ground
    O for Oscillator. and its 60 micro-farads

    You need a ferrite loop antenna hooked up from A to G
    You also have to know what the inductance value is to calculate the frequency.

    If you need a smaller capacitance (and don't use or need the oscillator) (to receive shortwave bands) then hook between the O and G you will receive higher frequency

    If you need a larger capacitance, (to receive the AM broadcast band) use the A and G

    If you want to receive VLF bands you need to hook the O and A together on one wire of the antenna, and the G to the other wire of the antenna.



    Hope this helps


    The ferrite loop antenna is an inductor and together they work as a tuned circuit for a radio receiver.
     
  6. radiosmoke

    Member

    May 30, 2006
    17
    0
    -------------
    Very simple:
    this is a two section gang variable capacitor.
    That means that as the capacitor shaft is turned the capacitance increases or decreases depending on rotation.

    The leads are marked A for antenna and is 120 micro-farads
    G for ground
    O for Oscillator. and its 60 micro-farads

    You need a ferrite loop antenna hooked up from A to G
    You also have to know what the inductance value is to calculate the frequency.

    If you need a smaller capacitance (and don't use or need the oscillator) (to receive shortwave bands) then hook between the O and G you will receive higher frequency

    If you need a larger capacitance, (to receive the AM broadcast band) use the A and G

    If you want to receive VLF bands you need to hook the O and A together on one wire of the antenna, and the G to the other wire of the antenna.



    Hope this helps


    The ferrite loop antenna is an inductor and together they work as a tuned circuit for a radio receiver.
    A
    [​IMG]
    G
     
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