J
JURB6006
Guest
Hi;
Me again. This has got to have something to do with the 9-1473 module (conv
control).
The DC control is fine, the rasters move linearly in all directions. Most of
the controls do nothing so I traced it back to IC4006. A vertical pulse is
supposed to be fed into pin 22 but it is attenuated. Now looking at this
circuit (no print) they have a 10K resistor working into a .1uF. Anybody got a
print and can tell me what's what here ?
Also I found a shorted diode off pin 25 but replacing it did no good.
The other thing is that the vertical pulse input to the module has quite a bit
of DC component. Is this correct ? Was it maybe some type of production change
? I ask because I changed the sweep module twice with the same effect. The
original one had a hole burnt in it near the yoke plugs.
The pulse is quite attenuated through the 10K resistor, even with a 4.7 uF I
put in series with it and the .1 uF removed from the circuit (C4070). It's got
to be the IC pulling it down, but I already changed it with no effect.
Any ideas ?
Thanx in advance.
JURB
Me again. This has got to have something to do with the 9-1473 module (conv
control).
The DC control is fine, the rasters move linearly in all directions. Most of
the controls do nothing so I traced it back to IC4006. A vertical pulse is
supposed to be fed into pin 22 but it is attenuated. Now looking at this
circuit (no print) they have a 10K resistor working into a .1uF. Anybody got a
print and can tell me what's what here ?
Also I found a shorted diode off pin 25 but replacing it did no good.
The other thing is that the vertical pulse input to the module has quite a bit
of DC component. Is this correct ? Was it maybe some type of production change
? I ask because I changed the sweep module twice with the same effect. The
original one had a hole burnt in it near the yoke plugs.
The pulse is quite attenuated through the 10K resistor, even with a 4.7 uF I
put in series with it and the .1 uF removed from the circuit (C4070). It's got
to be the IC pulling it down, but I already changed it with no effect.
Any ideas ?
Thanx in advance.
JURB