spark and hissing from crt EHT CONNECTING POINT

Thread Starter


Joined May 27, 2011
Need help
spark and hissing from CRT EHT connection point ie in side the CRT

Is it because of faulty CRT ????????????

help electrocraft

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Joined Sep 21, 2010
Picture showing discharging the HV using an earthing probe. The most likely place for arcing is from the conector under the insulating cap to the grey coating on the out side of the tube. Usualy caused by dust & moisture. Remedy is to clean the insulating conector & surounding glass on the tube, donot scrub the grey coating of as this is the earth. If this doesnt cure the arcing apply a little neutral cure silicone to the edges of the insulator & refit & let cure. The other posibility is if its arcing inside the tube then the EHT may be excessive should be around 25KV, or the tube is no longer under a vacumm.