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Okay need some advice and help. I did a full cap kit on my K4600, double and triple checked all polarities and joints etc. On the first power up the monitor came alive and all was well for about 30 secs when all of a sudden I heard a static type noise, the screen did the CRT horizontal bright off thing, similar to the android phone CRT animations and then I saw smoke.

Followed the smoke to the R504 resistor on the power board. It was totally burnt up.

What now?

The main power transistor has something rattling inside and it directly feeds power through the blown resistor. I'm hoping that it's the issue and that my tube didn't blow. :(

You should post this in the monitor repair section on KLOV there are a few guys there that really know their stuff.

R504 is on the audio and power PCB.
C501 is a 10uF 160V (i packed probably a 250V) Double check the polarity on that cap.
Also check TR501.

Also just to tell you. I've done cap kits to monitors that were kind of working only to have them blow something immediately afterwards. It's like the shitty caps were keeping the thing alive.

I totally believe that Ian. I think I opened up a can of worms with this K4600. There's been so many little mods and fixes done to it I have no idea where to even start.

Start with the burnt resistor. Check for shorts on that pcb. I listed to things that are around to check.

Oh awesome didn't see that post, thank you. I sure hope I didn't blow the yoke or tube or something more serious.

The resistor blew on the small power pcb but this is what my XY board looks like  ???

(https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.34s.jpg)
https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.34s.jpg

(https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.08.jpg)
https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.08.jpg

(https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.17s.jpg)
https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.17s.jpg

(https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.47.jpg)
https://dl.dropboxusercontent.com/u/85675826/2014-04-26%2012.55.47.jpg

I've thought about bringing it al back to stock but may never see it work again... idunno.

Some of those might be factory installed mods. If you have the patience I will pull my K4600 out and take pictures. I need to cap it anyways. In the mean time double check those items above. You will have to remove the transistor before you test it.

Thanks Ian, I'm patient.

The cap polarity is good and nothing is bridged. Am looking for an alternate to the TR501 locally. It's a 2SC1740Q, not sure if a straight 1740 will work or what. If I was going to pull it out thought I may as well just put a new one back in.

Considering the price on these transistors I would advise you to just check it. No sense replacing unbroken parts.

Wise words my friend, thank you. Need to learn and not pick up bad habits. It's funny, I'm looking at it now and it's a C1815 that's installed, not what it should be???

I'll test it anyway as I need to learn how to do that.

schematic lists it as
2SC1740 or 2SC1815

Ah seeing that now, it's funny because on the parts list it shows the Q, silly me I never looked deeply for that number on the schematic.

Okay pulled the transistor and checked it and I think it is bad, please correct me if I'm wrong. Here are my results.

Emitter to Base = No resistance either way, just .OL (BAD)
Collector to Base = Positive on COL, Neg on Base I get a reading 4.76 something. (GOOD)?
Collector to Emitter = A reading of 4.96 (BAD) I shouldn't get a reading correct? It should just be .OL

Are you testing in resistance mode or diode mode (does your multi meter have a diode mode)?

Resistance mode, no diode mode that I can see. (Fluke 12)

TESTING DIODES
1. Insert the test leads in the jacks.
2. Put the slide-switch in the continuity/ohms position. The meter selects either the
continuity/diode (R G) or ohms (e) function.
If ohms is selected, press [g] to toggle to the continuity/diode function. To toggle
the beeper on or off in continuity/diode test, press [V]. R is displayed when the
beeper is enabled.
3. Touch probes to the diode (Figure 5A). A forward-voltage drop of about 0.6 V
(typical for a silicon diode) causes the meter to beep once.
4. Reverse probes (Figure 5B). If the diode is good, OL is displayed. If the diode is
shorted (Figure 5C), the beeper sounds continuously in at least one direction.
If the diode is open, OL is displayed in both directions.

from the manual for the fluke 12

Okay, I'll try it again Ian, what am I looking for, shorts I guess?

http://www.allaboutcircuits.com/vol_3/chpt_4/3.html

Cool website, thanks.

Well I pulled up the datasheet and checked my pinout and I had it wrong. Retested with both methods, resistance and diode and apparently the transistor is working :( Guess that's not my problem. I'm getting a forward working voltage of about .696v from the Base+ to the Emitter and Collector. Nothing from Base- to each and nothing from the emitter to collector.

Check TR502 and X503 (or D503 i cant read the number)

Will do, thanks for all the help man!

TR502 checks out. Did just the same as other one but checked the datasheet first this time :)

X501 and X502 both check out as well, couldn't find a X or D503.

Maybe it just needs the voltage set after the cap kit? I have all the parts but without finding something that is broke I think it'll just smoke again.

Well there really isnt much else I can think of off the top of my head. Maybe get the meter ready and lower VR501 as low as possible and work from there. Are the fuses still good too? The part of the circuit we have been checking is the power input stuff.

Only seeing one 3a fuse on the main board and it's fine. I've checked all the caps again and again for polarity and soldering, just can't find anything, I wish I could find a screw up to end this.

Maybe the voltage needs to be checked. Just have to figure out where and what it needs to be as I'll only have seconds to pull it off, back to the manual. 

It may be time to post on klov, buffet will surely know the answer.

Buffett doesn't work on 4600s. I rebuilt two, in both cases I just capped and reflowed them and they work great.

Well I posted on KLOV but no responses yet. Put it all back together again and fired it up and whoosh R504 blew up again. Thank goodness for the ceramic containment tube that's around that. Guess it's designed to blow and that's supposed to protect the rest of the stuff.

I'm at a loss, something is causing a massive current draw I guess and just frying that resistor. Since the voltage regulators and transistors check out it must be some sort of a short or something, I don't know. Tried measuring the B+ but all I was getting wasn't getting much of a reading plus it only took about 5 seconds for it to blow.

It's either something I did directly or a symptom of the fresh caps. Could it be like a degaussing coil short or something... bad ground... I have a spare K7901, not sure if I can use it or not but have been thinking of giving up. Sending it out for repair just doesn't seem financially viable.

Frustrated.  

Went crazy and pulled everything off the power pcb, cleaned and stuck it all back on and the resistor no longer blows. My left side screen stretch issue is still there though, no idea what's causing that. Thanks to all for the help, wish I knew what it actually was though but was really losing my patience.

So it's fixed? Great work! Who needs Klov? :)

Yep, the weird blow up problem is fixed. The original issue and why I did the cap kit however is still there. I put in my spare k7901 and that problem wasn't there so it is the monitor for sure just don't know what. Gotta say though I was expecting more than one reply on klov...

Are you sure this isn't an adjustment? Did you adjust the horizontal hold and size pots?

Gonna work the pots some more today. Noticed they haven't been responding very well. The horizontal width is doing nothing at the moment. Vertical size works nicely though.

BINGO

I did screw up, I did screw up!! I shouldn't be so happy but I was looking at some before pics today and I noticed when I first stuck the two caps on the power PCB I swapped them. I stuck the big cap in the big spot and the small in the tight spot, seemed logical...  ::) I remember jamming the big cap where it didn't want to go yesterday so started to think about it. Thought I did it wrong actually when in fact I did it wrong the first time. I checked and checked the caps over and over for polarity and soldering but never actual placement!

Man I feel like a turd, all I can say though is I learnt a hell of a lot. Thanks Ian for being a good teacher and making me do the right stuff.

[shaking my head]