I just connected a wire of approx 30 cm (10") at the end of a 50 ohm coax between core and shield) and plugged into my Lecroy scope (1M) . I put a 10 dollar equivalent of Dutch money in a A4 PVC baggie and shaked the coins up and down. The most amplitude i got was when i dropped the bag in the middle of the wire . It showed up to 3 Volts tt. I did not get any apparatus upset . Relative humidity in Holland was 44 % at 21 degrees Celsius. (office temp).
I repeated with a TEFLON folded baggie and got slightly more amplitude. Is it the money or is it the bag or the humidity, i did not found any interference at all on equipment under test in my test lab. The Dutch guilder is made on nickel. Regards, Gert Gremmen Ing. == Ce-test, Qualified testing == Consultants in EMC, Electrical safety and Telecommunication Compliance tests for European standards and ce-marking Member of NEC/IEC voting committee for EMC. Our Web presence: http://www.cetest.nl List of current harmonized standards http://www.cetest.nl/emc-harm.htm 15 great tips for the EMC-designer http://www.cetest.nl/features01.htm -----Original Message----- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org] On Behalf Of Tony J. O'Hara Sent: donderdag 18 maart 1999 15:58 To: INTERNET:r...@twn.tuv.com Cc: [unknown]; [unknown] Subject: Re: explanation of ESD events with coins in baggie. Ok. Not as complex as I thought-in the TV! It sounds like "simple" RF interference through the antenna. However, I have just tried shaking the "coins in a baggie" at my computer monitor - nothing! Now at a 24 year old TV on wire antennas in my basement. I got nothing at VHF frequencies (54MHz to 216MHz) but I do get some white "birdies" on UHF. There is more of them the higher I go. Highest I can get is channel 59 (746MHz). Conclusion:- the "coins in a baggie" generates high frequency RF noise, but it doesn't seem to be at a very high level. I had to be very close to the antenna, shake it real vigorously and then I didn't get many random "birdies". Maybe 20 or so over the screen!! I can get a lot more interference especially at VHF tuning, just "sparking" the wire ends coming from a 12Volt DC power supply together!! Rene, when you took a scewdriver and rubbed the metal blade along that radiator seam maybe you were slowly discharging youself of a charge generated as you walked over to it, causing sparks and hence RF. Tony O'Hara --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
