UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - ITT CVC7

Focus Diode · 8th Mar 2006, 10:13 am

Any joy with the CVC7 Neil 29? When the service posistion is set to give a blank raster it should be bright white (when purity is correctly set). When set to the next posistion one should get a collapsed frame to facilitate grey scale setting up. If coloured lines at the centre of the screen arn't visible try adjusting the A1 controls on the convergence box until they can be seen. Each of the lines should be of equal brightness of course to allow for correct grey scale.

My own CVC5, a 20" RGD CR20 model, doesn't have its original CRT. The one fitted, which was not the original one was low emission. It was a Hitachi type. Ironically I had an identical Hitachi type ex GEC 2110 series which was known to be in first class order to hand which is as crisp as ever nine years later with first class grey scale on setting up. Should you replace the CRT in your CVC7 if it turns out to be faulty don't be surprised if this causes the IF transistors to fail, giving no raster, (unless service switch is set) and SW Radio on sound! This happened to me! They're on a small sub-panel and is far easier to remove this from the PCB using plenty of desolder mop to replace the transistors. I used 2x BF167s and a BF199 successfully with no further trouble.

Cheers from Brian

8th Mar 2006, 10:13 am	#15
Focus Diode Octode Join Date: Jan 2006 Location: Borough of Gateshead, UK. Posts: 1,420	Re: Itt Cvc7 Any joy with the CVC7 Neil 29? When the service posistion is set to give a blank raster it should be bright white (when purity is correctly set). When set to the next posistion one should get a collapsed frame to facilitate grey scale setting up. If coloured lines at the centre of the screen arn't visible try adjusting the A1 controls on the convergence box until they can be seen. Each of the lines should be of equal brightness of course to allow for correct grey scale. My own CVC5, a 20" RGD CR20 model, doesn't have its original CRT. The one fitted, which was not the original one was low emission. It was a Hitachi type. Ironically I had an identical Hitachi type ex GEC 2110 series which was known to be in first class order to hand which is as crisp as ever nine years later with first class grey scale on setting up. Should you replace the CRT in your CVC7 if it turns out to be faulty don't be surprised if this causes the IF transistors to fail, giving no raster, (unless service switch is set) and SW Radio on sound! This happened to me! They're on a small sub-panel and is far easier to remove this from the PCB using plenty of desolder mop to replace the transistors. I used 2x BF167s and a BF199 successfully with no further trouble. Cheers from Brian