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#46
04-07-2009, 09:57 PM
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Okay: Here's the voltages for each pin. They're all way too low...
Pin 1 measures at 0 volts Pin 2 measures at 0.75 volts Pin 3 measures at 0.18 volts Pin 4 measures at a whopping 2.0 volts And pin 5 measures at 0 volts. All these measurements were taken with the HOT reinstalled. 
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#47
04-07-2009, 10:08 PM
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Check the voltage at both ends of R007, the 5.6 ohm, 2 watt resistor that I think you replaced. If you have roughly 150 volts on one end; but, nothing on the other, the resistor is open. If you have little or no voltage on either end of the resistor, recheck the voltage at the positive terminal of the large 470 uf, 200 V cap. If you have voltage there but not on resistor R007, there is a problem between the cap and resistor. Maybe the trace is broken.
Did you check the new HOT to make sure it didn't short when you first powered up the set with the new parts?
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#49
04-07-2009, 10:31 PM
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Not on my schematic. If you use your ohmmeter to check between pin 3 of the regulator (which one end of R007 connects to) and the plus side of the big filter cap, you should read around 5.6 ohms. With the set off and unplugged, I'd measure the voltage across the 470 uf filter cap to make sure it's not holding a charge. If the cap is holding a charge, (and it very well could be) it will get your attention in a most disturbing way if your not careful.
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#51
04-07-2009, 10:57 PM
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OK, now I'm starting to get confused and that ain't good. It sounds like you are checking from pin 2 instead of pin 3 of the regulator. There is a 10K resistor between pin 2 and the filter cap. One end of R007 should connect directly to pin 3 of the regulator. Did you check R001, a one ohm, six watt resistor? It's in the power supply area.
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#52
04-07-2009, 10:59 PM
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I took R007 out of circuit after following the trace from the positive cap lead to the regulator, and finding that it was the only resistor in the circuit.
r007 is bad. now I'm confused, as that resistor tested good two hours ago.
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#53
04-07-2009, 11:01 PM
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Recheck the HOT again to confirm that it's not shorted. If it's good, the only other thing I can think of is to change the STR30130. They should only cost a few dollars. If you don't want to order one, just sit the TV back. It's a common IC in '90's TV's and I'm sure one will turn up in some junk real soon.
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#55
04-07-2009, 11:15 PM
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Nope. no STR30130 IC's in my stockpile. Guess I'll have to scrape enough together to order one. One of my Zenith chassis has a big regulator IC, but were i to guess, they aren't as interchangable as HOTS are...
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#56
04-07-2009, 11:19 PM
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The Zenith will probably have an STR53041 and it won't work. If you have any STR30xxx series IC, you could try it to see what happens. The last three digits of the STR30xxx line indicates the output voltage. There were STR30120's, 125's, 132's, etc.
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#58
04-08-2009, 12:14 AM
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And, when you order that STR30130, try to get it from a place like MCM or tritronics. Many of those $1.99 discount house specials are not worth the effort. Many won't work at all and others will work for a while and then bite you in the butt.
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#59
04-08-2009, 01:00 AM
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Yippie.
First I'm going to try the two local TV repair shops around here. It's apparently a common IC. I might get lucky. Of course I need the cash first. I already cashed in the pop bottles to get the 5.6 ohm resistors. It's too damn bad those 2003/2004 JVC chassis I have don't have the right IC... nothing wrong with those chassis. Just pulled them cos the CRT's were weak.
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