nashou
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Post by nashou on Apr 1, 2015 17:46:47 GMT -5
JustGreg said:
I got the Idea of using Inductors from a post on AVS by Mike parker. An inductor is a coil
wrapped around usually a ferrite material. This chokes out any noise that might be present
in the power line , and you want to use it on both the incoming and out
going rails. In Mike's thread on" VIM 02 Succes" he uses them on the CLM rails to clean them up.
hope that helps
Athanasios
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nashou
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Post by nashou on Apr 1, 2015 17:47:29 GMT -5
Joust:
I have some huge 270uh indutors i got by mistake that i was going to use on my VIM but they are too large to fit, they should work great for these 24 volt rails.
Athansios
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nashou
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Post by nashou on Apr 1, 2015 17:48:24 GMT -5
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nashou
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Post by nashou on Apr 1, 2015 17:50:40 GMT -5
1031 Said:
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nashou
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Post by nashou on Apr 1, 2015 17:51:39 GMT -5
1031 Said:
Thanks Jarmo for taking those readings, I looked up the specs and i need to increase to a higer amp rating for those, can you also test the 24 volt rails too. I have some 270uh inductors that are 4 amp rated to use, the ones in the pics are only .44 amps!!! :shock: too low for that ! But i did watch Hitman last night with no problems, great looking movie since i think it was filmed in HD.
Thanks for your input and any more help and suggestions are deeply appreciated.
Post has been edited to state amp current draw.
Athanasios
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nashou
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Post by nashou on Apr 1, 2015 17:52:58 GMT -5
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nashou
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Post by nashou on Apr 1, 2015 17:54:22 GMT -5
Thanks Jarmo! I will still add those beefier 270uh inductor on the 24 volt rails and replace my smaller 220uh indutors on the 15 volt rails. Thanks for the heads up on the current draw ,the 220uh are probably good for my CLM and VIM but the focus board and HDM(still looking at schematics) will most likley need a larger current draw capability, this is where a scope would come in handy. Regarding the Big Pink plastic caps, Mcpheve said that they couple the dynamic focus, so I assume that a better cap will help stablize the current in that dynamic coil? Maybe you could swap out one of those caps before any others are changed on that board and put the scope on the out put to the dynamic coil and see which has a more stable current/pulse. Like said in the beggining of this thread I am not an EE nad any help we get for this thread will be of great help!  I didnt do a long test after each part replacement so i cant tell if any one part replacment makes a difference but overall the focus board has much more stability after all mods are done as a whole. Like you said the 1000uf cap replacement I say made the biggest improvment, then the op amp replacement next. I did those changes first before i recieved the rest of the parts for all the other cap changes, the inductors i did while writting the post for the thread. I thought you meant the 6 470uf i changed to 1000uf...but I was thinking fo changing those non polars with a higher lower esr cap but havnt looked around to find a replacement do you think a film cap would be better here? Athanasios |
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nashou
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Post by nashou on Apr 1, 2015 17:55:40 GMT -5
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nashou
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Post by nashou on Apr 1, 2015 17:59:08 GMT -5
Ok everyone, thanks to 1031(Jarmo) for pointing out the current draw through those +/- 15 volt rails the inductors i had were to low an amprage only .44 and Jarmo scoped them to have peaks up 1.5 amps so I edited the post and also added a section on how to add same inductors to the +/- 24 volt rails. pic of higher current inductors I also Ordered caps for the three non-polars Jarmo mentiond and will try those once they come in. www.mouser.com/Search/ProductDetail.aspx?R=UET2A101MHDvirtualkey64700000virtualkey647-UET2A101MHDAthanasios |
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Post by jbmeyer13 on Apr 22, 2015 9:52:35 GMT -5
EDIT: To keep the HVPS regulated better for the transients from Dark to Bright with out blooming Chris Stevens added 4 125f 100 volt Wet tantalums to the 390 volt rail coming into the HVPS. Well to find those caps cheap is not easy. So I came up with using A single HV Film Cap. here it is on Justins HVPS.    That was a good mod;-) |
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Deleted
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Post by Deleted on May 16, 2015 7:36:50 GMT -5
My red drifts about half an hour before it gets steady. On my CineMax there was almost no drift or 5 minutes at most. Will modifying the convergence board solve this or is this normal Marquee behaviour? The baords I use are reasonable new like 2005 or so but the drift seems temperature related so I would go for the electrolytic capacitors if others say they have less drift on their Marquee's. Thanks!
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Post by mastertech on May 16, 2015 21:39:40 GMT -5
Does the blue drift also or just the red?
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Post by Deleted on May 17, 2015 4:13:53 GMT -5
Does the blue drift also or just the red? Just the red. And it drift even more than half an houre. I watched games of thrones and by the end it stabilised now that is a bit to long for me |
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Post by gjaky on May 17, 2015 4:48:29 GMT -5
Is that the static convergence which drifts?
The static convergence power amplifiers are made from 2 stereo aduio amplifier chips on the HDM, using one for blue and green, leaving the red alone on the second amplifier package. Although they are screwed together to have better heat tracking, but obviously this is impossible to reach at the junction.
This have been discussed earlier...
A possible improvement is to replace these power amplifiers with a three-in-one chip.
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Post by Deleted on May 17, 2015 5:35:08 GMT -5
Is that the static convergence which drifts? The static convergence power amplifiers are made from 2 stereo aduio amplifier chips on the HDM, using one for blue and green, leaving the red alone on the second amplifier package. Although they are screwed together to have better heat tracking, but obviously this is impossible to reach at the junction. This have been discussed earlier... A possible improvement is to replace these power amplifiers with a three-in-one chip. Ok that is valuable information. It is indeed the static that is drifting and I have heard that other also had red drift on Marquee. I can try another HDM. The drifting is mostly vertical by the way does that meen it might be the VDM? |
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I didnt do a long test after each part replacement so i cant tell if any one part replacment makes a difference but overall the focus board has much more stability after all mods are done as a whole. Like you said the 1000uf cap replacement I say made the biggest improvment, then the op amp replacement next. I did those changes first before i recieved the rest of the parts for all the other cap changes, the inductors i did while writting the post for the thread.
