[NJARC] Cleaning metal fragments out of a radio tuner

[antqradio at sbcglobal.net]

I have actually done this on one radio's tuning capacitor a few years ago; the coolness factor is undeniable.  Whenever you hear crackling from the loudspeaker when you tune across the band, you will need to do this.  Al's advice on removing all connections to the cap is appropriate.  No need to do any damage to other parts of the circuit.
I also suggest that you limit the current from the power supply to a level that will protect both you and the capacitor.  Whatever the voltage that is available from the power supply you use, calculate the value of a resistance, of appropriate wattage, to go in series with the power supply to limit it's current to 100 mA or less.  If the debris in the capacitor cannot be cleared by this reduced current then it is certainly big enough to see and be removed with tweezers or strips of paper soaked in a solvent like alcohol.  You will need to let the alcohol evaporate before you continue with the process.  No need to set the place on fire!
This procedure is of course dangerous to life and limb so my Air Force tech training kicks in.  I suggest that you remove watches and rings and put one hand in your pocket!  Then sit back, away from the setup, and watch the fireworks!Jim

      From: Al Klase <ark at ar88.net>
 To: njarc at mailman.qth.net 
 Sent: Friday, January 13, 2017 11:09 AM
 Subject: Re: [NJARC] Cleaning metal fragments out of a radio tuner
   
 Matt,
 
 You're right.  It's absolutely imperative that you disconnect the stator of the variable cap from EVERYTHING else.  Other wise you'll likely burn up the coil associated with it.  Also, you need a power supply that doesn't mind a short circuit on its output.
 
 I read about this in old books, but never saw it done.  Thanks, Bob.
 
 Al
 
 On 1/13/2017 11:42 AM, Matt Reynolds wrote:
  
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#yiv0026035152 #yiv0026035152 -- P {margin-top:0;margin-bottom:0;}#yiv0026035152  For the ignorant out there that barely know how to work on this stuff (me), is this dangerous to the rest of the set?  Like Victor said, it's not defined how its' hooked up (but I'm assuming one side is hooked up to the plates that move and the other to the stationary plates).  I assume this would only be a good idea on "hollow state" stuff... 
  Regardless of any of that, it was cool to watch and looks like fun... 
  Matt
    From: NJARC <njarc-bounces at mailman.qth.net> on behalf of VICTOR BELLINI <pipiepiper at gmail.com>
 Sent: Friday, January 13, 2017 11:34:01 AM
 To: David Sica
 Cc: njarc at mailman.qth.net
 Subject: Re: [NJARC] Cleaning metal fragments out of a radio tuner      Just remember
 Reply = Poster
 Reply All = Everyone
 
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http://www.skywaves.ar88.net/ 
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