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I heard it claimed that you cannot test the conductivity of conductive RF shielding paint with a Volt / Ohm meter. This was in reply to someone who had done so and claimed that the paint was ineffective because they did not detect any conductivity.

Is this true, and if so, why?

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    \$\begingroup\$ Why would an audio signal-level meter be able to measure conductivity? Also, RF conductivity does not require DC/audio-frequency conductivity, which I believe is how the paint works. Using the right instrument for the job is important... \$\endgroup\$ – user2943160 Jul 22 '16 at 21:06
  • \$\begingroup\$ Sorry that was stupid on my part. The person claiming the paint not registering conductivity said "VOM" and the person answering with the claim that you could not measure the conductivity said "VU Meter" and I copied that text ignorantly assuming it to be another synonym for Volt / Ohm meter. I'm going to revise my question...or should I just abort and write a new one? \$\endgroup\$ – EricS Jul 22 '16 at 22:43
  • \$\begingroup\$ Instead of making the comment, please use the "edit" link to change both the question and title. \$\endgroup\$ – DoxyLover Jul 22 '16 at 22:49
  • \$\begingroup\$ Followup to my previous comment. In the discuss i'm referring to, I don't know if the 2nd person typoed VU meter, if they misunderstood the first person, or what, but for simplicity I will just edit my question to say VOM meter since that's really what I'm interested in an answer to. \$\endgroup\$ – EricS Jul 22 '16 at 22:57
  • \$\begingroup\$ @DoxyLover Should I not make these explanatary comments here? My concern is in making these other comments and answers no longer make sense after editing my question. \$\endgroup\$ – EricS Jul 22 '16 at 22:59
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Shielding paint, when still wet, often has large resistance. The conductive particles are still floating around, separated. You have to have patience and only measure it when properly dried.

To make good contact with pointy probe tips, the conductive paint needs to be fairly thick. Make some thick blobs on the painted region, far separated, and wait for them to totally dry. They'll be the contact-spots for probes. Lay the tips on them at an angle, to give widest contact area.

That, or attach small pieces of conductive copper adhesive tape to the well-dried paint in two separate spots. The tape's conductive adhesive makes wide-area contact, even when the probe-tips could not.

Last resort: embed very clean, very thin copper wires in the wet paint. When dry, measure resistance between the wires. First tape them down so they don't shift at all, since they can easily crack loose while inside the paint, yet they'll appear to still be in good contact.

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A VOM can be used to measure conductivity (i.e. resistance in Ohms). However some conductive properties are difficult to measure unless you use the proper technique. Just poking it with typical meter probes may not properly measure the conductivity.

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