19K7xxx with new flyback blowing fuses

Looks like the R98 resistor got cooked, I'm suspecting due to a bad solder joint (looks like theres no pad either), anyone have any expierience with these? According to WG its a 2.2k Ohm 1W resistor and I cant find it anywhere. Guess its mouser time?
 
Asked Bob, he does have the resistor I need. Anyone think of anything else I should look at before placing another parts order? Game is sold and I need to fix it as soon as possible.
 
check c36 and c38 see if they're in tolerance if ther're blown it will pop the fuse.
and check the H.O.T as well if its blown your fuse will blow as well
 
I have replaced the hot, voltage regulator and that fried resistor. Worked for about an hour, now blowing fuses again. Any more ideas?
 
Were the HOT or VR damaged, or did you just replace them because you had the chassis out?

Have you checked C36 and C38? You can use your meter to see if they are shorted or open. Measure for continuity and you should see the meter increment up to a larger value the longer you hold the leads on. If you read an open or dead short then that component needs to be replaced.

Also, check the solder points on R101 and R99.
 
I cant get the numbers to climb with a continuity test, but I can get a zero reading at C36 and nothing for C38. I can get zero readings at R99 and other resistors. Cant find R101, and R98 is what I replaced already.

So C38 is the culprit? If so, its listed as a .39uf 5% 200V PP (guess a quick radio shack run is out).
 
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Test for resistance across the capacitors and resistors, what do you get?

Also, any time you get a short (zero, or very near zero ohms) you should pull at least one leg of the component and test again. It is not unusual for components to be in parallel and the readings can be skewed by the circuit. By pulling the components out of the circuit you can identify which one is shorted.
 
I pulled C38 completely, no reading. I also get no reading when I pull the resistor I replaced.

I'm about ready to give up, spent way too much time and money on this already. What am I missing? On top of that, I now have a 4600 with a similar problem. Anyone want to swap both of these for a good one?
 
is it immediately blowing fuses on power up now or still a slow reaction on fuse popage?.
could be hard to figure on a slow reaction. would have to get some key point readings.. nothing you will be able to do with a multimeter.. if you hit a dead end and are able to wait about a month then I could be of service.. good luck!

ps.. I am restructuring and turnaround time is going to be cut in half
 
Heres the timeline...

1. Received game working with a focus drift, The flyback has a huge crack and white knobs that wont turn properly. But it can be on for hours without issue (other than the focus drift).

2. Replaced Flyback. Game worked fine for about a week. Went to turn it on one day and nothing to the monitor. Noticed a blown fise. Replaced it, blew again immediately.

3. Pulled chassis. Noticed a fried resistor and solder pad at R98. Replaced resistor and soldered one leg to another pad on the same trace as the damaged pad. Also replaced the hot and VR. Game worked good for an hour or two, then blew fuse again.

Now every time I try a replacement fuse, it blows in a second or two. Setting my multimeter to Ohm test, I cant get a reading from C38 whether its removed or not. C36 gives a near zero reading as does all the diodes in the power section. R98 gets a near zero reading when attached and no reading at all when removed. I have another brand new resistor that also gets no reading, so I'm guessing this is normal.

I have 3 multimeters and they all work fine. I'm just not familiar enough with monitors yet to know exactly whats causing this, or how or where I should be poking at it. Cap kits and flybacks are easy, guess I need more education on this part of it... either way I'm stumped because this wasnt an issue until I replaced a bad flyback with a new one, one week later the power problems started.
 
What kind of multimeter do you have?

When testing C36 if you don't have an auto ranging MM set it to 20K on the Ohm setting. If you get 000's all the way across then you have a shorted capacitor. If you get a 1 then your meter is set to too low of a range. Getting a 1 when testing a resistor means the resistor is open.

You do not test Diodes in the ohm setting, you have to test them using the diode setting on your MM.

When testing a resistor if you don't know the value and if you don't have an auto ranging meter you can look at the band colors and search for the value. You can also look up it's value by noting it's location and referencing it in the K7000 manual. You can download a copy of the K7000 manual here. If your MM is not auto ranging then you want to set your Meter to a range within the value of the resistor your testing or slightly higher.

You can also do a google search to find out how to test the individual components using a multimeter.

How to test resistors

 
Thanks for that, this was alot of help. OK so after learning how to properly test diodes (according to the video) I have tested every diode I could find. Most are reading around 525 except for the 2 near the flyback (D13 and D14 IIRC), They are reading around 330. Then I swapped positive and negative leads. Again, looking at the video, it appears I should get a zero reading when doing this, but I'm acually getting higher numbers, around 750, D13 at around 800 IIRC. D14 will climb for a few seconds until it goes past what the meter can read, then just shows a 1.

Then after reading how to properly read a resistor using the color bands and setting my meter to test it, I tested R98 again, along with a brand new one of the same value (R98 was the one that was originally fried and replaced). The one on the chassis is getting a zero reading, looks like its shorted. The new one of the same value is reading 2.2, which looks like the proper reading to me.

I still cant get any reading on C38 regardless of what I do, and still get a near zero reading at C36, again regardless of what I do.

I am thinking a good idea might be to replace C38 & C36, and possibly D13 & D14. Something is causing R98 to short, maybe one of these? Any advice on where to go from here?
 
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I recently fixed a K7000 chassis with a bad D13, a bad D13 will give you vertical collapse. I wasn't popping fuses with a bad D13. Have you gone through the flowchart?
 
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