UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

wd40addict · 6th Feb 2018, 1:30 pm

You can just disconnect the capacitor for now.

It reduces the ripple on the HT line from about 0.7v rms to about 0.15 rms. The set will work fine without it, but you can see the picture expand and contract slightly as the Aurora generated 50Hz beats gently with the mains 50Hz. With it in circuit this effect becomes virtually invisible.

However given the amount that the picture size varies anyway with scene brightness it's not essential. If you do replace it ensure adequate voltage rating. It has ~185vdc on one side and ~200vac rms on the other. so must be able to tolerate (200*1.4) + 185 = 465vdc. Which is the worst case during a negative AC cycle.

6th Feb 2018, 1:30 pm	#19
wd40addict Octode Join Date: May 2009 Location: Stevenage, Herts. UK. Posts: 1,518	Re: Bush TV22 restoration You can just disconnect the capacitor for now. It reduces the ripple on the HT line from about 0.7v rms to about 0.15 rms. The set will work fine without it, but you can see the picture expand and contract slightly as the Aurora generated 50Hz beats gently with the mains 50Hz. With it in circuit this effect becomes virtually invisible. However given the amount that the picture size varies anyway with scene brightness it's not essential. If you do replace it ensure adequate voltage rating. It has ~185vdc on one side and ~200vac rms on the other. so must be able to tolerate (200*1.4) + 185 = 465vdc. Which is the worst case during a negative AC cycle.