Definitions/Dirty Needle
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Dirty Needle
Definitions → D → Dirty Needle
1. symbol D.N.-erratic agitation of the needle which covers less than a quarter of an inch of the E-meter dial and tends to be persistent. (HCOB 8 Nov 62)
2. ragged, jerky, ticking needle, not sweeping. (HCOB 15 May 69)
3. a dirty needle is any needle which departs from the appearance of a clean needle. (SH Spec 224, 6212C13)
4. a dirty needle is only a little, tiny persistent rock slam. (SH Spec 184, 6208C14)
5. one that jerks, tips, dances, halts, is stuck or has any random action on it with the auditor sitting looking at it doing nothing. (HCOB 30 Dec 62)
