John, Not sure that degaussing would be what you want. My guess is that the north/south permanent magnet is on that disk. Then the coil causes a magnetic field that moves the disc and the pointer with it.
Every analog meter I know has a permanent magnet somewhere and a coil to create a deflection relative to the permanent magnetic field. The Drake meters are "backwards". Most meters have a moving coil and stationary magnet. Drake has a moving magnet and stationary coil. I believe that is you degauss the disc, the meter will never work again. Thought anyone else? 73, Ron WD8SBB --- On Sun, 3/13/11, John Meyer <[email protected]> wrote: From: John Meyer <[email protected]> Subject: RE: [Drakelist] T-4XB Meter To: [email protected], [email protected] Date: Sunday, March 13, 2011, 1:58 PM Ron, Thanks for your input. I'm a little afraid to try bending the needle. It's going to take a steady hand. I wonder if the problem develops because of some residual or stray magnetism. If that were the case possibly a degaussing device like used to demagnetize tape heads would resolve the problem. I believe I have one of those devices around here some place left over from my days of servicing tape decks. If I can dig it up it may be worth a try. Date: Sun, 13 Mar 2011 06:24:15 -0700 From: [email protected] Subject: Re: [Drakelist] T-4XB Meter To: [email protected]; [email protected] John, I have a meter here too that is the same way. It appears that the meter movement is made of a disc of magnetized? material inside of a coil. I was going to carefully bend the needle, but I happened upon "new" one. It's been some time, but I was going to approach as follows. Put a close fitting brass tube from the model airplane shop over most of the needle. With a very fine pointed pliers hold the base of the needle (above the movement bearing area). Now very slowly bend the needle in the direction needed. BTW this was the meter that left me with a small piece of plastic in my cornea. Just had my eyes exam this week, and doc tells me I am a very lucky. 73, Ron WD8SBB --- On Sat, 3/12/11, John Meyer <[email protected]> wrote: From: John Meyer <[email protected]> Subject: [Drakelist] T-4XB Meter To: [email protected] Date: Saturday, March 12, 2011, 1:37 PM #yiv1199727915 .yiv1199727915ExternalClass #yiv1199727915ecxyiv213230379 .yiv1199727915ecxyiv213230379hmmessage P {padding:0px;} #yiv1199727915 .yiv1199727915ExternalClass #yiv1199727915ecxyiv213230379 .yiv1199727915ecxyiv213230379hmmessage {font-size:10pt;font-family:Tahoma;} My T-4XB meter movement is off scale to the left of the zero mark. I have removed the meter and to my surprise there doesn't appear to be anyway to zero the needle. Any suggestion to get the needle to rest at zero would be appreciated. Thanks, John Meyer K8IHY -----Inline Attachment Follows----- _______________________________________________ Drakelist mailing list [email protected] http://mailman.zerobeat.net/mailman/listinfo/drakelist
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