CurtPalme.com Home Theater Forum

[Revox]

I know it's not the best idea to start a new topic, but i think noone would answer to my last most in "vision 1 noise".

The VDM does some buzz noise, i pointed out, that the noise is not comming from the elektrolyth caps, its comming out of the mylar caps.
The Problem is, that my 8500 gone so loud after i have glued a those 3 cabs, that i strongly recomend Help!



Now i am searching for those cabs, but i don't know what kind of cabs i should choose. I think normal Wimas Mks are to bad?

So i know a lot of you have more knowledge about the quality of caps than I. Whats special for those Mylar ones?

The next problem is, that there were a lot of VDM Versions, i need the value for the caps on a 50-2330-02P one.

I read the following technical bulletin:

http://www.curtpalme.com/docs/ElectrohomeMarqueeTechnicalBulletin_Tb95-07.pdf.

So i should use even 1uF Caps when a pointed out falures do not occur?

[Revox]

I red a little bit about caps yesterday night.
My conclusion was, that mylar ones aren't so special and normal mks ones have a lower ESR and so on.
So i installed little 1uF mks instead of those mylar ones.
The noise is totally gone! I think nearly everybode with a marquee got this kind noise, mabe you know the sound when you start the marquee. Its a high tzzzzzt then the normal buzz starts, caused by the vert deflection frequency.

But i am still not satisfierd with my sollution, because i don't know exaclty what those caps do.
It seemd that its a high frequence filter for the H-deflection output, the crazy thing is, that its not as usual with a R connected with a C to ground. Its the output directly connected with the cap with a 1Ohm resistor to ground. Especally because a 1Ohm Resistor is not very high, the engeniers might have calculated with the ESR of the Mylar Cap.
On the other hand, when those caps do mechanically swing the must emmit crap do the Vert deflection Coil, but mabe you do not noticed it, because the noise is emmited when the electronical ray flys back from botton to top?

The Bzz noise was there since i got the pj with 800h Runtime.

[Revox]

The best thing! The mod blows a geometry error away i had in the upper corner of the Picture. The very left of my picture was a little bit streched up horizontally!