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See images below : enter image description here

enter image description here

enter image description here

I obtained this component from an old radio set ( possibly 90s made). It was attached to the tuning dial, so most likely it is variable capacitor I believe. It has absolutely nothing written on it except on image 1, which is C1, C2, C3, and C4 as seen. The text in image 3 (wp0710) returns no result.

Also in image 3, the 2nd leg on left is internally attached to the capacitor.

Since this is my first hands on experience, I am absolutely clueless what are its various legs, and how to use this capacitor. I don't know how to wire this. If it would have been a simple 2 leg capacitor, it was no problem. But what to do in this case ?More important!y, how do I find out over what range does it vary. I have a digital multimeter at my disposal. Any help and additional information is welcome.

Additional information : The radio from which it was obtained was a 5 band radio : Mw(540 to 1600 khz) SW ( 60 to 19 m) FM( 88 to 108 mhz) Tv1(65 to 75 mhz) and TV2 (175 to 230 mhz). Also there was a single piece of it in radio.

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    \$\begingroup\$ Definitely a variable capacitor. \$\endgroup\$ – Ignacio Vazquez-Abrams Aug 1 '14 at 18:39
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    \$\begingroup\$ Your meter probably cannot measure capacitance that small very well, at least not without shielded leads and calibration, but it can help you determine which pins are connected to each other as shields. There are probably several distinct variable capacitors in there, traditionally 365 pF for the AM broadcast band while the high bands would be less. Build an LC oscillator with various coils and experiment, but you will need something such as a scope or spectrum analyzer (or general coverage receiver with a BFO) to detect the output. \$\endgroup\$ – Chris Stratton Aug 1 '14 at 18:39
  • \$\begingroup\$ Can you tell the functions of various legs ? I believe they are for different capacitors, but how do i use this piece? And what is that 2nd leg ? Also in image 3, on right side, are those 2 legs from back side just for support or something else ? \$\endgroup\$ – Plutonium smuggler Aug 1 '14 at 18:43
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    \$\begingroup\$ See this article for some useful information about this type of tuning capacitor in general. \$\endgroup\$ – Ben Miller Aug 1 '14 at 20:08
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    \$\begingroup\$ That's definitely a tuning capacitor with four trimmer capacitors on its back. Depending upon the manufacture, some of the trimcaps' leads would extend down to the PC board while others may fine-adjust the top or bottom of the primary capacitor. At one time those things were really really common. \$\endgroup\$ – TDHofstetter Aug 21 '14 at 18:39
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It's a variable capacitor which is commonly used in analog portable (FM?) radios.

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