Monochrome monitor questions?

If it's got vertical lines that's jailbars, you need to replace the capacitor that filters the B+ to the video amp, on color monitors it's normally on the neck board, on mono monitors it can be there or on the main board.

It can also be striations due to velocity modulation of the H-scan. It's common to have a line linearity coil in series with the H-deflection yoke windings on monochrome monitors. There is usually a damping resistor across this coil, to stop it ringing immediately after the flyback ( retrace ) period. This resistor commonly goes open circuit, allowing the coil to ring, producing the velocity modulation of the beam as a result of the decaying sine wave that then gets impressed on the rising sawtooth.

Arfa

Use an ESR meter and do an ESR test on all the caps, especially in the scan and power supply circuits. It is possible that on an older monitor, you will find many caps that are out of specs.

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JANA _____

The problem I'm having is the screen has vert. lines spaced about every

The pc board consist of some discreet components and two IC chips. TDA1175 (vert) and TDA1180 (Hor). Both chips have been replaced as well as the tube.

Any ideas what the problem could be, an area to look at? I have a copy of a schematic, but don't now how to post it here for viewing.

Thanks. Jeff

-- A7N8X-Deluxe, AMD XP2500+ (Un-locked)

An -UPDATE- on the jailbar problem.

It turned out to be some newer type FBT we installed on an older board, since the old style FBT were not available. We pulled a few old style flybacks from scrap boards and installed them on the boards in question. The problems on this sample lot all disappeared.

Thanks.