[ Neotec NT2701 ] Clicking Noise

iN33DCaTNiP

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Breifly mention in other thread about issue I was having with my crusin usa med res game..... So i power up the system and get nothing, no picture what so ever not
even neck glow on the back of tube and/or any hv.. normaly if I put hand on front of crt tube I can feel it getting power but I don't... all I get is clicking sound from chassis. is
it flyback the cause of clicking and no power on tube ? I'm not in too much on the monitor except 40 for 2 complete chassis.

now out of the 2 chassis I have , one is complete and only oddity of that is the rubber cap on anode has hairline crack but not. broken

help please lol
 
I removed the chassis from monitor, looked all over the board, found nothing no caps/resistors blown and/or ooozing .. I looked at my 2nd chassis I have for this 27" and see same thing....nothing blown/oozing

I'm trying to figure out if doing a capkit + flyback is worth the trouble for $65 for this monitor.... was hoping it would be simple fix lol
 
Neotecs I'm told are a little fragile in the HOT department. healthy capacitors are necessary to preserve the life of them... as bizarre as that sounds.

there's a process where you adjust the B+, but then you adjust the shutdown to where it will shut down if it even slightly increases. my guess is since it's a switching mode power supply chassis, when the old caps go out of spec, the B+ increases and pops the HOT.

the flybacks are also total shit on these as well.

you might wind up sending this one out.
 
Neotecs I'm told are a little fragile in the HOT department. healthy capacitors are necessary to preserve the life of them... as bizarre as that sounds.

there's a process where you adjust the B+, but then you adjust the shutdown to where it will shut down if it even slightly increases. my guess is since it's a switching mode power supply chassis, when the old caps go out of spec, the B+ increases and pops the HOT.

the flybacks are also total shit on these as well.

you might wind up sending this one out.

good point, I'm going to mess with b+ and turn it all way down, then find out where test point is on this thing to measure dc voltage.. worst case is I can take the hot from parts chassis and put it on this one
 
def no b+, still ticking, so next is to cap kit ?

found these 2 areas of board where charred marks are

this is full family version
 

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The flybacks on them aren't very good. Mine developed cracking in the focus block. Symptom was monitor would go out of focus as it warmed up.

If your tube is a Zenith, watch out.... the guns go or short in these after a while. My NT-27E with Zenith had a gun with 0 gain, one with > 10 gain, and one with 7-8 gain. In clean/rejuv, I unshorted the first gun and got it to > 10 gain, but that shorted the one with > 10 gain. Needless to say I had to excessively clean/rejuv the guns to achieve balance... and now they all measure about 4.5 gain (where 5 is considered minimal 'good'). It does work, but it will have a short life I'm sure.

While I have some K4600 WG monitors that still have original caps.... and work, the caps in the Neotec were crap in comparison. (Yes, I will be doing a cap kit in that old 4600.... I just haven't gotten to it yet).

If your tube is good, get a flyback, get a good quality cap kit, and you might be ok. My HOT was fine, no semiconductors were gone on my chassis. I believe the HOT would fail shorted so it should be easy to test with a DVM (take it out of circuit to test).

If your tube is good, I say fix it unless you have something better in a 27" medium res monitor kicking around.
 
The flybacks on them aren't very good. Mine developed cracking in the focus block. Symptom was monitor would go out of focus as it warmed up.

If your tube is a Zenith, watch out.... the guns go or short in these after a while. My NT-27E with Zenith had a gun with 0 gain, one with > 10 gain, and one with 7-8 gain. In clean/rejuv, I unshorted the first gun and got it to > 10 gain, but that shorted the one with > 10 gain. Needless to say I had to excessively clean/rejuv the guns to achieve balance... and now they all measure about 4.5 gain (where 5 is considered minimal 'good'). It does work, but it will have a short life I'm sure.

While I have some K4600 WG monitors that still have original caps.... and work, the caps in the Neotec were crap in comparison. (Yes, I will be doing a cap kit in that old 4600.... I just haven't gotten to it yet).

If your tube is good, get a flyback, get a good quality cap kit, and you might be ok. My HOT was fine, no semiconductors were gone on my chassis. I believe the HOT would fail shorted so it should be easy to test with a DVM (take it out of circuit to test).

If your tube is good, I say fix it unless you have something better in a 27" medium res monitor kicking around.

I'm going to do cap kit 1st since it doesn't cost as much as the flyback and go from their. thanks for advise.
 
https://www.arcadepartsandrepair.co...nt-2700-nt-3500-li-chin-monitor-cap-kit-105c/

https://www.arcadepartsandrepair.co...700-nt-3500-full-family-monitor-cap-kit-105c/

remember there are two different versions "full family" and "li chin" and if you need i have both with the best quality caps in the kits.

I chked my neckboard, it says full family, my 2nd chassis doesn't have anything stamped on either chassis but its same board but looks like diff revision on neckboard if tht matters. neither main chassis have anything stamped only the one I'm testing does
 
I chked my neckboard, it says full family, my 2nd chassis doesn't have anything stamped on either chassis but its same board but looks like diff revision on neckboard if tht matters. neither main chassis have anything stamped only the one I'm testing does

look at C118 and C119 caps and what is the value on them and that will tell you which one you have.
 
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