Neotec 2515C Vert Collapse

SiLeNtNiNjA1

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I recommend all the caps replaced, if never replaced before.
but for this picture change C306,C308,C307
are most likely to cause this type of image
other caps that should be replace are C312,C315,C314,C305,C313
Needs Ic 301 La7836 Vertical Ic.
anytime the pump up caps are getting weak to bad
they will effect the ic,so if you just replaced the caps and left the ic
it will fail soon..Its your call..Now or Later?
Good Luck!
 
I recommend all the caps replaced, if never replaced before.
but for this picture change C306,C308,C307
are most likely to cause this type of image
other caps that should be replace are C312,C315,C314,C305,C313
Needs Ic 301 La7836 Vertical Ic.
anytime the pump up caps are getting weak to bad
they will effect the ic,so if you just replaced the caps and left the ic
it will fail soon..Its your call..Now or Later?
Good Luck!

Thanks. I just dropped in an order on the cap kit. Ill try to find the IC and replace it if I can find it.

Scratch that - thanks ebay! IC ordered to :)
 
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Can anyone with this chassis send me some high res photos of the area around Ic 301 La7836 and C316 22uf 25v np cap? I have some traces by the IC that didnt quite look right, and some solder joints by the cap that were jumped together, but im not sure if they were supposed to be. Ill be checking over the IC traces tonight and hopefully can find something.

no luck with the above - If nobody has any other ideas I'll order a new flyback for it tomorrow and try that. I hear they can cause odd things on these neotec's.
 
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Was c309 in the cap kit.
the Tantalum cap?
If its not a bad trace, try to replace C309 seen it fail before.
One other thing i notice in my notes was the NT2515c had a La7835
for the vertical ic but the schematic show's the La7836
i had a La7835 so i put one back in,but no notes on c316
the NP it may have checked good so i did't replace it.


Check the remote board connections and the vertical Pots they will crack.
you have to look at them real good..
If not fixed yet.
What are the voltages on the Ic?
Let us know what you find.
 
Nope, C309 was not in the kit. I will order one of those guys.

I already replaced C316 with an axial, since nobody local had a radial np.

I looked at the old IC, and it was a matching la7836.

IC Voltages :
1 : 25.2
2 : 9.4
3 : 12.1
4 : 0
5 : 14.0
6 : .1
7 : 53.4
8 : 26.4
9 : .5
10: 0
11: 49.4
12: 57.0
13: 9.9

I didnt see anything on the remote board, and the pots seem to have some effect, but they dont affect the problem :\

Thanks again for the input.

Edit : Tantalum cap (1uf - 35v) tests at .9843uf with my LCR, so it dosnt look like thats the problem either...
 
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Voltages are all wrong.

Here are some general voltages measured in a working circuit.

Ic 301
1:11.6 Vcc
2:4.6
3:5.8
4:0 ground
5:5.9
6:5.3
7:20.0 Vcc
8:2.2
9:1.4
10: 0
11:11.6
12:20.0
13:4.8


Measure your B+ @r117. around 125v's?
@r118 for 25v and 12v @ZD101 a zener in the power supply.
your 12v line is 25 and your 25v line is 53.4
to much voltages,chip maybe in thermal protection.
 
So am I correct in looking at this as T101 (Power Trans T6002) needs to be replaced? I also see the Drive Trans(LJ90003) and Pin Trans (LJ90002) Aside from the flyback, but the source of it seems to be T101.

Any guess on where to find one? Mouser didnt list the part number.

PS - The last Cap - 220uf 400v tested at 167uf w/ my LCR meter. Ill replace that guy to while im at it.

One more edit - BOM lists C104 @ 330uf - 400v, This chassis came with a 220uf 400v. Can anyone confirm what theyve got?
 
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So am I correct in looking at this as T101 (Power Trans T6002) needs to be replaced? I also see the Drive Trans(LJ90003) and Pin Trans (LJ90002) Aside from the flyback, but the source of it seems to be T101.

Any guess on where to find one? Mouser didnt list the part number.

PS - The last Cap - 220uf 400v tested at 167uf w/ my LCR meter. Ill replace that guy to while im at it.

One more edit - BOM lists C104 @ 330uf - 400v, This chassis came with a 220uf 400v. Can anyone confirm what theyve got?

You sure your meter is working correctly
maybe a weak battery?
most the filters i see is 330uf..


what is the B+ voltage should be around 125v..
can you adjust r112 and lower the secondary voltages?
are you using the correct ground for measuring voltages.
what ground connect are you using?

you shouldn't have that much voltage on a 12zener it should be 12vs
check it over again..with those voltages the set shouldn't working at all.
something isn't right..
 
For the ground, I was using the metal base around the chassis, where the green ground wire is bolted on. The B+ is 122.3v.

If the filter should be 330uf, which is what the bom lists, ill replace that. Hopefully the local electronics supply has one on hand.

Ill drop a fresh battery in my meter and re-test when I get home from work tonight.
 
Alright, cheapo levitron meter is getting trashed. It seems to work with ac fine, but dc was way off when I put my sperry on it for comparison. ZD101 was 12.0 - R117 & R118 were both 25.2. I'll go over the IC again later tonight when I get back home. Looks like the levitron was doing ac on both sides.
 
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Ok, now with the good meter,

IC 301
1 : 11.8
2 : 4.7
3 : 5.9
4 : 0
5 : 7.0
6 : 0
7 : 23.7
8 : 7.8
9 : .6
10: 0
11: 20.2
12: 26.1
13: 4.9

R117 - 123.0
R118 - 25.7
ZD101 - 12

So I followed IC 301 Pin 6 back, and found C312 (2200uf 35v) had 19.8v on one leg, 0 on the other. Tested it w/ my LCR, and got nothing. This was a brand new cap. Ill try 1 more just to see if it was a bad cap to begin with or if something blew it out. I should probably check the resistors along pins 8 and 11 on IC301 as well, since they are also high.
 
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