![]() ![]() ![]() it needed, in my opinion, some lubrication of the mechanism, and a good cleaning of the inside surface of the FL display window, one owner-low usage, damn-near pristine cosmetics,įresh tune-up/maintenance work in the service shop, and 40 of the better quality late-80's S-VHS cassettes. But I don't think anyone would want to wait another 2 year for a board like that.I've wanted one of these for years, and this one is now mine. In fact based on this design I had a faint idea to make a similar baughterboard specially made for Marquees, that would contain all the performance related circuits at one place, so the VIM could be ENTIRELY bypassed from the signal path, and the VIM would only supply the menu OSD signals to the neckboards, and do the input signal's sync processing. The whole input stage is bypassed on the VNB, my interface board directly drives the output stage of the VNB. Each neckboard has an own local (low noise, high speed) regulator that feeds the low level analog circuits. The neckboard output stage (+/-85V) is fed from a totally separate power supply from the projector. Here are some highlights about this XG-VNB project: These boards do that with ease, at some point I may play with the opamp, but other than that I can't imagine any other modification that could seriously affect performance. And as you could see it does not show significant roll-off at 310MHz pixel clock (some distortion yes), but I use my projector at 1080i 96Hz anyway, that is only 138MHz pixel clock. Modified boards not fitting well to my wallet Besides, I did some (performance aimed) modification to the VNBs myself. Why not? You plan on making them more than stock as times goes? I want to help you if I can and if you reconcider you know where to reach me. Thanks I'm not really into buying modfied boards. If you don't mind me asking, what are you using to take those screenshots in this thread? It's my old set used in any screenshots that I've made. If you want to make a deal on a set of MP Marquee VNB I could sell you them, you would only have to reattach one pin on one of them to have a full set. That's great work! Those are my stock Marquee I sold you 2 years ago? Has it been that long already, time really flies away. 0 sereies even have nice bandwidth by stock form, but those are only AC machines), they emply low capacitance tubes just like the LUGs, also the deflection yokes have very low inductance (you know it is a small yoke) therefore virtually there is no raster ringing not even at very high scanrates. The XG is a nice machine otherwise (the XG. Perhaps they used Thomson yokes because they had the original Marquee 9000 designed around the 40kV Thomson tubes, which later dumped, but all the "driver" boards were taylored to the Thomson yokes already, with new yokes they'd have to redesign most of the boards as well. This requires modifiying the yokes and the driving circuitry as well. The engineers say that the Thomson yokes are "good enough" and maybe that's true for their military and commercial customers,īut one of my projects that I'm not actively working on at this precise moment is to adapt all the magnetics from a Barco 909 to the Marquee chassis. The choice of the Thomson yokes is, in my opinion, the one big glaring design choice error that was made when the Marquee was designed. Thomson yokes that Marquees come equipped with. Yes, I noticed that the XGs use the Kanto-Denshi deflection and focus yokes, which are (by now) well known to be superior to the In fact I have enough parts to build two more set of these boards (except for the VNB) but I hardly imagine anyone would spend even $300 for boards like this. While the NEC may have 8" tubes but it has far more powerful beam control both in focus and in convergence than a Maruqee ever dream of, comes with factory color filtering that is also not cheap on a Marquee. With the XG the bandwidth was worse than on the PG xtra which was quite strange, and mine is not a unique instance as I found. BTW I had once a Marquee though only a 7500 (8500 without astig)in stock form I found that even a NEC PG xtra was better in every aspect except for fan noise. In europe there isn't that much supply of CRT projectors of you can choose. I know from experience,Įven swapping around magnetics from one type to another can have unforeseen complications. Wouldn't it just have been easier to get a Marquee from the very beginning?īut seriously, that's some impressive re-engineering that you've put into that. Projectors in the past : NEC 6-9PG xtra, Electrohome Marquee 6-7500, NEC XG 1351 LC ( with super modified Electrohome VNB neckboard !!!)Īfter more than two years I can say this project is DONE! ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |