bad lines sanyo 14"

saleem

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get bad scan lines on the monitor (was told they are scan lines) i have recapped the chassis and i have adjusted the brightness level on the chassis and the pic adjustment brightness pot also with no change.

its a sanyo 14"

pic linked of problem.

thanks
:)
 

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get bad scan lines on the monitor (was told they are scan lines) i have recapped the chassis and i have adjusted the brightness level on the chassis and the pic adjustment brightness pot also with no change.

its a sanyo 14"

pic linked of problem.

thanks
:)

Have you adjusted the Screen brightness pot on the flyback?
 
Looks like the 'screen' adjustment is set too high (one of the two adjustments on the flyback transformer - the part with the red high voltage lead that connects to the picture tube).

One is 'focus' the other 'screen'

If that doesn't adjust it maybe the FBT is shot (FlyBack Transformer).
 
There are 3 brightness pots
1. brightness on the frame
2. sub-brightness middle of the chassis
3. master brightness on the flyback

adjust the master brightness on the flyback.
 
there is only a focus control on the flyback,the screen is located on the neck board.i have twiddled enough with this now and it just dosnt go away,i can try again but,its night time here in uk so i would prefer to mess with it during day time.
:)
 
you have adjustments right next to the tube and by the neck board. just alittle more adjusting should do it for ya, i bet.
 
i have adjusted every concievable pot and the prob will just not go away.the story is,i bought a nonworker cocktail and the monitor was not working.i had already bought 2 prior,i got 1 worker out of them and wanted to buy the one (that had the nonworker monitor) for parts to get the other working.anyways,the one i had already had a working monitor and a nonworking transformer,the one with the nonworking monitor had a working transformer.

i got a cab up and running out of the 2 but,in the process i actualy swapped tubes to the others chassis's (just swapped tubes round),so the one i had went into the nonworker (chassis) and this resulted in me getting it running,so now i got this spare monitor.prob is,i got these scan lines now.

its had recap and you can see the adjustments when the pots are turned its just the lines refuse to go.
:(
 
i have adjusted every concievable pot and the prob will just not go away.the story is,i bought a nonworker cocktail and the monitor was not working.i had already bought 2 prior,i got 1 worker out of them and wanted to buy the one (that had the nonworker monitor) for parts to get the other working.anyways,the one i had already had a working monitor and a nonworking transformer,the one with the nonworking monitor had a working transformer.

i got a cab up and running out of the 2 but,in the process i actualy swapped tubes to the others chassis's (just swapped tubes round),so the one i had went into the nonworker (chassis) and this resulted in me getting it running,so now i got this spare monitor.prob is,i got these scan lines now.

its had recap and you can see the adjustments when the pots are turned its just the lines refuse to go.
:(

These days we are starting to see "non standard" component failures happening more and more. Well, the major problem is your "standard" get well kits don;t include the necessary items. And when you add new parts in with old it's also not unheard of to cause extra stress and blow something else out of spec.

I see you didn't mention adjusting the B+. Anytime you do a capkit you need to readjust the B+.
 
i had the exact same prob before i did the recap,i did the recap and the prob persisted.i see the b+ on the chassis but,i would not know the correct way to approach it.
:)
 
i had the exact same prob before i did the recap,i did the recap and the prob persisted.i see the b+ on the chassis but,i would not know the correct way to approach it.
:)

The problem is caused by incorrect voltages feeding the tube. You will need to get a circuit and find what those voltages should be OR measure the output of the screen pot on the neckboard and then track back - you will probably find a resistor in the chain that has gone high. (assuming the B+ is correct & that you have replaced the caps in this part of the circuit, normally 250V ones).
 
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