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FERNSEH · 20th Sep 2015, 4:57 pm

We all acknowledge that passing a small current through the line output transformer windings to drive out any moisture is a good idea. Well, the transformer in this set the EHT overwind has a resistance of 19Kohms therefore supplying 30 volts from a bench power supply will not warm the transformer by any significant amount. 30 volts will result in only 00158mA passing through the winding which will mean that the heating effect will be only 0.047 watt. That's not enough. However, apply 200 volts will result is 1.05mA through the 19000 ohm winding which is going to be just over 2 watts.
Four new wooden blocks have been made for the new cabinet castors.
Once these have been fitted it will be possible to move this heavy set about without any difficulty.

20th Sep 2015, 4:57 pm	#17
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Ferguson 247T: huge console TV set. We all acknowledge that passing a small current through the line output transformer windings to drive out any moisture is a good idea. Well, the transformer in this set the EHT overwind has a resistance of 19Kohms therefore supplying 30 volts from a bench power supply will not warm the transformer by any significant amount. 30 volts will result in only 00158mA passing through the winding which will mean that the heating effect will be only 0.047 watt. That's not enough. However, apply 200 volts will result is 1.05mA through the 19000 ohm winding which is going to be just over 2 watts. Four new wooden blocks have been made for the new cabinet castors. Once these have been fitted it will be possible to move this heavy set about without any difficulty. Attached Thumbnails Last edited by FERNSEH; 20th Sep 2015 at 5:12 pm.