neotec nt-2701 just blew a new hot

cadillacman

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i have this condition unknown neotec 2701 monitor i picked up..

upon inspecting, the metal piece that wraps around the flyback and hot was missing, the hot was shorted and flyback was cracked.

I replaced the flyback, replaced the hot, made a new metal piece to shield and mount the hot onto.......

fired it up.. after about 4 seconds of nothing i started getting pulsing sparks from around the seperate (power??) pcb that mounts on the left side along with chirping..... after verifying that nothing was touching my new metal piece, i realized that the metal piece was NOT grounded...

I ran a seperate ground wire to the metal piece.. arcing has stopped but im still getting the horrible chirp of shutdown.. hot is dead shorted again...



SO my question is, could that seperate pcb not bieng properly grounded cause the hot to blow? if not what else should i try?? can somebody check thier 2501 or 2701 with a meter and tell me if that metal piece should be insulated or grounded?

lmk.. (stupid pos) i was really hoping for a ez fix on this.. not my day/luck i suppose. thanks again fellas.


in the meantime i guess i should make sure i got the correct hot...
 
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I had a 2701 come into the shop with a blown HOT. Everything else looked good. I replaced the HOT....and it blew immediately. After doing some hunting...someone installed the wrong HOT...and I just followed their lead. After getting the correct HOT all was good (well, except for some horizontal tearing issues, but that's another issue). Also, make sure you've got an insulator behind the HOT.

Edward
 
hot on these is fully encapsulated- no need for a insulator.. (EDIT 2/8/10 I WAS WRONG IT DOES NEED ONE!!!!!!!)

unless both the old hot and replacement hot i got from chad were wrong parts...


can anyone look at thier monitor or manual and tell me what hot came in this thing from the factory?
 
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BU2532AL = Q402. Also check C450 for a short if it keeps blowing the HOT.
 
sometime syou just wan tot kick yourself in the nuts.

Got a replacement hot from mouser, to my suprise it came with a insulator..

I could have sworn the hot was fully encapsulated, but nope, back is bare lol.. big mistake on my part there...


so, redid my metal piece, made sure all was grounded. Replaced the hot, made sure it was well insulated. Checked c413 no short.. checked c450 no short

put it all back togther made raster.. great.. hooked it up to video(std res just for testing- i understand it wouldnt be perfect..)

went to play with pots on the remote board and boom, lost pic.. losing static on the tube too.. BUT however i can still hear it chatter like its still on.. real odd..
hot not blown, fuse not blown...

on powerup i can hear the static fire up then go away.. shutting down hv i sould assume..

does anybody know of anyone with a manual so i can check and adjust b+ and hv?


so now wtf heh.. i guess i better pull it all back apart and check for more krappy solder, this thing did have a ton on it..
 
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Per the manual:

Adjust R111 to set the horizontal deflection B+ (the connection point of D106) to
100.0 +/- 0.50VDC.

Check the other output DC voltages or AC wave to meeet the following specs:

1) The connection point of D109 = 140V +/- 2.0VDC.

2) The connection point of D107 = 26.5V +/- 1.0VDC.

3) The connection point of R130 = 12.0V +/- 0.5VDC.

4) The connection point of (FBT #9/R429) = 24Vp-p +/- 1Vp-p

HTH.
 
found r101 has cold solder.. reflowed, powres up again.. shes def med res as i am getting triple images heh but somethings there..

cant find r111, i have r112???? where the heck is d106 i can find 104 and 105 but not 106
 
in my case r112 did adjust b+, ima tard and found d106, its a large diode duh lol... i had to set b+ a little high (110vdc) to get d107 to also read closely to its spec.. dont know if thats an issue or not..


gonna let it burn in awhile and see what i get..

i wish i had a med res rgb tester or med res game to make sure all is copasetic but damn man i cant believe i resurrected this pig!


now if i put this in a game i get to worry about if the xray is messed up as i dont know how im supposed to adjust that lol.. i guess if i start growing a leg form my forehead ill start worrying....


ran for 30 mins os far so good.. will update post if it breaks again which is very possible lol

in also very happy to find out that theres really no screen burn and colors look nice too.. WHOOHOO!!!

now i just gotta find a cheap med res driver to throw this thing into!
 
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