neotec 2701 c423 cap help

i do... they are very close to the correct value and in tollerance..
not the exact value however they will work great for c423 application.
I use them all the time. $5.25 shipped.


.82uF 400v 5% P-Prop .82uF 400v 5% polypropylene capacitor. 25 $5.25


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Interesting. I did a cap kit and replaced c423. Still chirping. I am going to swap the HOT next.
 
Remember, there are two versions of the 2700 series:

"Full Family"

"Li-Chin"

Seperate service manuals & schematics were issued.
 
Ken,
I cannot find a manual for either version anywhere. Your's still have not been uploaded on here.
 
No man, sorry to say. I had to put that chassis on the back burner for a while. I was contacted by someone on here back when I was working on it (I do not recall who) and they advised that I change out the HOT and VR. They said that is what they did. Then they turned the adjustment down on the chassis and slowly turned it up and the monitor functioned perfectly. I wish I could give you more concrete information than that but I cannot pull up any deleted PMs on here. Let me look around and I will let you know.

Edit: Eyeless tossed his and I can see why. :D
 
I repaired the nt-2701 in my san francisco rush recently. It was as full family version. When I got it, it had a dim screen. I turned up the fly back and pop no video. Pulled the board out and tested the HOT and it was dead. I replaced the hot and they flyback and put the chasis back in and it powered up but had vertical collapse. I bought the ic301 vertical chip and the ic401 sync chip. Replaced ic301 first and still had vertical collapse. Replaced ic401 then I was back in business. Except that the screen was too wide and the horzontal width pot did nothing. I replaced c550 a np cap and everything looked good. My cap kit finally came in from twisted quarter, which was on back order so I put it in and of course the silk screen was wrong for two caps on my board and I smoked the resistor that was tied to d404 which is not in the manual. I turned the caps that were wrong around (the silk screen on top said one polarity and the dot on the bottom said the oppisite polarity so I recommend replacing them one by one on the neotec and if in doubt post or do like I did and follow the traces till you fine the one that leads to ground) I replaced the burnt resistor with a 2.2 ohm 1/2 watt resistor thanks to ohmerone for that info and then the picture looked bright and excellent. A few days later after leaving it on for about 8 hrs strait and it was back to chirping. Pulled it out and checked it over and C423 had split open. Since I couldn't find a replacement I tied two .47uf 400v caps together in parallel to get close enough to a normal c423. Put it back in and now we got high voltage again, But now we have vertical collapse again. Soldered a dip socket in to make future changing faster for IC401 and slapped in new chip. Now everything is looking good again. I pulled out all poly caps and tested them with a capacitence meter to see if I should replace them as well. All of them checked out within spec so I did a 2 day burn in on it which it survived. So now it looks to be working fine. Ken Layton posted the manuals for both nt-2701's and they have a good trouble shooting section I would suggest following. A big thank you to Ken and Ohmerone for making this repair easier.
 
I repaired the nt-2701 in my san francisco rush recently. It was as full family version. When I got it, it had a dim screen. I turned up the fly back and pop no video. Pulled the board out and tested the HOT and it was dead. I replaced the hot and they flyback and put the chasis back in and it powered up but had vertical collapse. I bought the ic301 vertical chip and the ic401 sync chip. Replaced ic301 first and still had vertical collapse. Replaced ic401 then I was back in business. Except that the screen was too wide and the horzontal width pot did nothing. I replaced c550 a np cap and everything looked good. My cap kit finally came in from twisted quarter, which was on back order so I put it in and of course the silk screen was wrong for two caps on my board and I smoked the resistor that was tied to d404 which is not in the manual. I turned the caps that were wrong around (the silk screen on top said one polarity and the dot on the bottom said the oppisite polarity so I recommend replacing them one by one on the neotec and if in doubt post or do like I did and follow the traces till you fine the one that leads to ground) I replaced the burnt resistor with a 2.2 ohm 1/2 watt resistor thanks to ohmerone for that info and then the picture looked bright and excellent. A few days later after leaving it on for about 8 hrs strait and it was back to chirping. Pulled it out and checked it over and C423 had split open. Since I couldn't find a replacement I tied two .47uf 400v caps together in parallel to get close enough to a normal c423. Put it back in and now we got high voltage again, But now we have vertical collapse again. Soldered a dip socket in to make future changing faster for IC401 and slapped in new chip. Now everything is looking good again. I pulled out all poly caps and tested them with a capacitence meter to see if I should replace them as well. All of them checked out within spec so I did a 2 day burn in on it which it survived. So now it looks to be working fine. Ken Layton posted the manuals for both nt-2701's and they have a good trouble shooting section I would suggest following. A big thank you to Ken and Ohmerone for making this repair easier.

Retro, we cannot thank you enough for this. Excellent post sir. Great information. Thanks again.
 
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