Quote:
Originally Posted by ZenithNut
I was tunning the h efficiency coil so that makes sense why there was no change. I do not have a plastic hex. I have an "Ifixit" tool case with the proper size hex end but it is metal.
I dont have a vcr BUT i have a lot of old cartridge based nintendo and sega video game consoles I can use for a composite source. So youre saying to fire up the scope attatched to a blank composite source and then dial in the scope to get a wave form then keep the scope on those setting and attatch the scope to the tv and adjust the h slug to match the wave from a blank input setting from the composite signal of my choice?
I might end up doing some reflowing. I had audio and video before the chassis went on the bench. Now theres no sound or video. All I did was replace a few ecaps and re silicone the fly. Thank you for your help Tom.
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Definitely get a plastic alignment tool and stop using the metal one before you crack your slug... I've been there done that, and can say removing a crack slug without destroying the coil can be a royal pain in the butt... sourcing a new slug can be tricky too.
The only thing you will need to change on your scope is the vertical voltage scale. Composite video is about 1vpp and h osc waveforms in tube set are on the order of 50vpp...
How new your game system is can be important if you plan to use it as a H frequency reference. Older game systems used 240p rather than 525i. That change shifted the horizontal frequency a bit, and while most sets can sync to it I'm leery of using some random spec a programmer came up with because they were too cheap/reasource strapped to create a proper NTSC spec video source.
If you lost video and sound together you probably want to check tuner and IF systems. Wiggle tubes and if you get noise that stage and everything between it and the video detector diode are fine. In some cases the IF lead to the tuner will open or go intermittent... I have a CTC15 clone where the tuner and it's IF lead are permanently connected to the main chassis with soldered wire. The point the IF lead solders to the tuner has no strain relief so when I pull the chassis the center conductor of the IF lead tends to break off of it's tuner solder post... killing both picture and sound.
Do you have raster? If not check your boost voltage. Troubleshooting, adjustment and repair all get easier with the screen lightning.