Star Gazer
Stern Electronics, 1980You're currently viewing posts by Pinsider barakandl.
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ebay.com link: LM323K LM323 TO 3 Voltage Regulator 5V 3A
lol
same date code even.
yeah that is likely a china fake. The transistors, voltage regulators, etc have way many more fakes out there than chips it seems.
The only regulators i would use from China would be used pulls with obvious markings from lock stars biting into the case.
Quoted from Fytr:Someone on the other thread said they also removed R49.
Should I leave R49, remove it, or remove and also replace wth a wire?
mimic the 5v regulator circuit on a wms sys 3-6 games. The two resistors Bally uses juices up the output voltage for a lm323k, often to a dangerous, MPU-U15 zapping voltage.
For the PSU5 switch mode regulator, it would be cut out r49 and change r50 to a jumper wire / 0 ohm resistor.
Quoted from Fytr:Made some progress on the weekend.
Removed R49, replaced R50 with a jumper wire...Success!!
I now have solid 5V everywhere it should be.
Unfortunately, running the board in the game shows a problem with the high voltage section, when running the display digits are fading in and out instead of being sharp and bright.I adjusted the pot under the high voltage to max settings, didn't help, at least not much, and I'm seeing the following values on my MM:
TP4 177v
TP2 153v
I have already replaced the big caps on this board, so not sure what other components need replacing to resolve. Possibly another bad voltage converter on the high voltage section? *sigh*
Check the voltage at the rectifier board test point. If low there check the 1n4004 rectifier diodes on the power supply as maybe one is open circuit.
If looks good there, check the ground return and positive rail connector at driver board. They hv ground is isolated back to the transformer panel (unless you do the "ground mods").
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Tempe, AZ