K4600 problems. Need advice

woodmedic

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I just capped my K4600 horizontal monitor. Before the repair it was wavy going down both sides. It resembles the hula picture on the flow chart. The motion of the waves is pretty slow. In the manual it states to check the blue lead on TR502 for B+ of 127. When I checked it was around 109V. I tried to adjust the voltage using VR501 but the pot has been glued at the factory and I could not get it to budge. Would the voltage being around 109 cause what I am seeing? What is the best way to break that VR loose?
 
You've got one of three possible problems:

1. Your capkit did not include capacitors for the power/regulator board.

2. The large B+ regulator transistor is open/bad.

3. Your B+ filter capacitor on the main board is bad (most likely this is your problem).

How to replace the main filter capacitor on a 4600:

http://homearcade.org/BBBB/k4600.html
 
since you have the chassis out make sure to reflow solder on all header pins and C621 i always recommend replacing too which is not included in cap kits. if you need parts i stock them all.
 
Thank you! I'll keep that in mind. I did reflow all of the headers when I had it apart for the capkit.
 
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