04-26-2016, 01:34 PM
Hey Crist,
> I'm k\leaving the tuner alone!
On a lot of the old tv's (pre 51 or so used turret tuners) there is an local oscillator adjustment that can be found behind the fine tuning knob. This adjustment can be helpful if you have a situation where have a good pic and crummy sound or crummy pic and good sound. Unlike the video IF where you need equipment, this can be adjusted by sight and sound. Some folks will also dittle with the discriminator transformer (read detector for the audio) for loudest / least distortion
As Mike said about the video IF unless you know someone that has the equipment and has done many times before I'd leave it alone. The picture and sound pass through this IF circuit so if they get out of adjustment it can screw up both sound and pic all at once. In the 60's manufactures changed the IF frequency from 21 mc to 45mc. Not a great idea by the manufacturer to use 21mc for the IF as it's in a ham radio band (15mtrs). Have been given a number 45mc sweep tv generators (usually strip for parts or chuck) but the 21 mc units may be just a little hard to come across. If you adjust the 4.5mc sound IF it won't mess with the pic.
Have fun! Not trying to scare you just help you make wise decisions.
Terry
> I'm k\leaving the tuner alone!
On a lot of the old tv's (pre 51 or so used turret tuners) there is an local oscillator adjustment that can be found behind the fine tuning knob. This adjustment can be helpful if you have a situation where have a good pic and crummy sound or crummy pic and good sound. Unlike the video IF where you need equipment, this can be adjusted by sight and sound. Some folks will also dittle with the discriminator transformer (read detector for the audio) for loudest / least distortion
As Mike said about the video IF unless you know someone that has the equipment and has done many times before I'd leave it alone. The picture and sound pass through this IF circuit so if they get out of adjustment it can screw up both sound and pic all at once. In the 60's manufactures changed the IF frequency from 21 mc to 45mc. Not a great idea by the manufacturer to use 21mc for the IF as it's in a ham radio band (15mtrs). Have been given a number 45mc sweep tv generators (usually strip for parts or chuck) but the 21 mc units may be just a little hard to come across. If you adjust the 4.5mc sound IF it won't mess with the pic.
Have fun! Not trying to scare you just help you make wise decisions.
Terry
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