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Old 18th June 2013, 10:16 AM   #1
TBL is offline TBL  Hong Kong
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Default Marantz 8b restoration: colour code, prints, schematics

Hi

I have two Maratnz 8b's, all around the serial numbers of 8-7XXX. I have heard that someone repairing 8b's have not seen two of them 100 % the same. Anyway, I guess, and hope their components and schematics will not be too different form each other. They two are primarily stock. But I havent't done a detailed check to see their dissimilarities.

Anyway, I wish to repaint the chassis and bodies. I wanna anyone can tell:

1. the colour code corresponding to the brown tint, and the matt/gloss ratio. Hope this will translate to better looks;
2. the colour code of the grey tint of the capacitors;
3. how can I make silk print screens to replicate the lettering on the top and the back of the chassis? If I can make a good print, it will be worth my effort to repaint it whole in the first place.
4. I used to have a PDF copy of the schematic. Anyone can suggest where I can get a good copy of its manual and schematics?


Thanks.
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Old 18th June 2013, 10:22 AM   #2
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Try here
https://www.google.co.uk/search?q=ma...ient=firefox-a
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Old 18th June 2013, 10:37 AM   #3
TBL is offline TBL  Hong Kong
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Harleyjon:
Yeah I tried the zilla.li place. All the computers and even my Android phone cannot open the manuals etc. Pressing on their hyperlinks freeze the system. Even after opening up to all cookie ....
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Old 18th June 2013, 11:46 AM   #4
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are the chassis really in need of paint?

doing exact silk screens will be very very difficult and a lot of work.

I'd think you'll need to take photos at high res and go into photoshop to work up the layout and fix any scratches or dings in the lettering.

_-_-

perhaps you want to post some pix?
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Old 18th June 2013, 12:31 PM   #5
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Quote:
Originally Posted by TBL View Post
Harleyjon:
Yeah I tried the zilla.li place. All the computers and even my Android phone cannot open the manuals etc. Pressing on their hyperlinks freeze the system. Even after opening up to all cookie ....
Zilla.li ... what is that?
The file is a png and within Google.

I have just checked the address and it works fine.
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Old 18th June 2013, 04:04 PM   #6
TBL is offline TBL  Hong Kong
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Zill.li is the first searched result from the google search tag.

Maybe it's a geographically limited website.
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Old 19th June 2013, 12:35 AM   #7
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Marantz 8 | Owners Manual, Service Manual, Schematics, Free Download | HiFi Engine
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Old 19th June 2013, 02:13 AM   #8
TBL is offline TBL  Hong Kong
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Hi All,

OK I got the manual and instruction.

bear: yeah that link asks for member log in wgich O don't have .
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Old 19th June 2013, 03:08 AM   #9
TBL is offline TBL  Hong Kong
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As to tHe brown and grey colours, I think I might have to bring the tranny housings of the two amps, and a cap, to an auto body shop to get a custom colour match.

I hope to post more pictures as the project goes. I observed it has clartity and uncoloured highs, but it leaves a lot to be desired in the bass registers no matter what tubes I used, including Mullard xf1, xf2, Shuguang EL34B, JJ, two sets of Tesla brwon bases. And it has been ripped of filtre caps at the "preamp" inputs too. So all its inputs go direct to the 6BH6. My Ampex 6973 console mono's has a lot to offer in terms of "body" and solidness. I guess these may be jsut the kind of characters that individual tube types show.

Anyway, my first 8b measured 364 VDC at the B+, and 406-409 VDC at the plates of the 4 pcs of EL34's. Might this be just about on spec of 360 and 390.

I wish to post pictures about the first Marantz 8b I bought last March, and which is in far better condition than the second one in body condition (tho itself it ain't "good" at all. See the rust). Note that it is using Blackcat and Imp caps. Gosh! Aren't those found usually on Dynaco and Eico?
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Last edited by TBL; 19th June 2013 at 03:30 AM.
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Old 19th June 2013, 07:10 PM   #10
rkoonce is offline rkoonce  United States
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I've done silk screening on DIY amps before. The most difficult part is coating and exposing the screen. I made artwork in a vector drafting program and printed it in dense black on clear film on a plotter I have access to at work. The screen is available in many sizes already stretched on a frame, which I recommend. You coat the screen with a photosensitive emulsion on both sides using a squeegee to even it out and remove any thick areas. After it dries overnight in complete darkness, place the printed film with the image upside down over the bottom side of the coated screen and cover it with a sheet of clear glass to keep it tight against the screen. Next, expose it to light. I used a clear 150 watt incandescent lamp in a reflective shade with the whole thing sitting on a black cloth to prevent reflections. The instructions with the emulsion will provide distance from the work and time for exposure. When the exposure is done, quickly rinse the screen with a forceful stream of water, *not* in direct sunlight. The unexposed portions of the emulsion will wash out of the screen leaving your image in uncoated screen. Place the exposed screen in position over your work, pour a small amount of ink on one end of the screen and squeegee the ink across the work. Lift the screen and let the ink dry. I sprayed a clear coating over the ink for protection after it dried. You can use a stripper solution to clean the screen for reuse with another image.
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