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milomax

Moog circuitry

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Hi everyone Im Les from the Uk and have just bought a 1980 Les Paul GK55 (bolt on neck) it has MOOG circuitry which was taken out by previous owner??? and now set up as normal Les Paul.. Ok i have all the circuitry and would like to replace but need some sort of diagram. They also did this set up with an SG

All i can find is this pic on flicker

 

http://www.flickr.com/photos/igorz/355730790/ HELP!!!!! PS i have enclosed a few pics thanks

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I am not up on my Moog circuitry.....Keep on googling until someone 'knowledgeable' weighs in..[thumbup] I am sure its 'out there somewhere'...[unsure]

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hello

Ive too been trying to find info on one of these boards. There an sg forum Type in my moog dilima into google couple more pictures there.

unfortantly i dont have a board. but have been trying to work backwards from any photos found on the net. found rd artist schematics seems to be 2 versions different numbers on board. sg overview curtisy of sg forum

post-57965-068631900 1372932933_thumb.jpg.

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Hi yes it is odd as there must be thousands of these models made the 80s cheaper gibsons have now nearly been forgotten... my guitar is in a guitar shop as the tech has been onto moog but they don't keep early records ( how odd ) so he is talking to the gibson rep???? but no answers.

 

yes the RD has two versions so if there available there must be records of earlier models..

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The smaller board in the previous post appears to be only the tone section of the RD77 Moog design. I have posted the original Gibson schematic for you.

 

Many complained that this circuit was noisy and the electronics were discarded. On my Artist, I noted that my RD was particularly susceptible to radio station interference. In this instance the original cavity for the electronics was never properly shielded. I have used sheets of copper foil adhesive for this need complemented with a nickle EMI reduction spray paint you can order from MG Chemicals. I will be addressing the issue of excessive noise in the future with the use of lower noise components. It's a project in process. Well she may not be 'original anymore' but the electronics as they stood needed to be fixed right!

post-13571-026390700 1373722054_thumb.jpg

post-13571-039225400 1373722065_thumb.jpg

post-13571-072208900 1373724477_thumb.jpg

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From what I see the board you have pictured is the same as an RD77 less the compression and expansion circuitry. You have active tone controls and a bright mode switch. I have attached another variant of the circuitry for those that are interested in this topic. The changes I have yet to get around to is to replace all the carbon film resistors with metal films from the KOA MF/MFS/RK series, replace the FETs with matched 2SK170's, while getting rid of that noisy TL022 with an OPA2227. You can even go as far as to replace the 2N3904's with a MPSA18. Audiophile the circuit in other words. Since the MC14007 is CMOS and possibly subject to static damage it can be socketed for a replacement. Everything is available from Mouser. The circuit design is not a bad one. We are talking about late 70's technology here and there have been component improvements. What I am suggesting would horrify a collector but what is worse ditching the electronics entirely? If you want to go further it is possible to re-plate the hardware with

 

http://www.caswellplating.com/electroplating-anodizing/brush-plating-products/plug-n-plate-kits.html

 

Because the pickups are encapsulated with epoxy you just cannot cut off the covers. Replacement screws can be gotten fairly easily too. Truly, it is a wonderful instrument to those very fortunate enough to own one.

post-13571-047344400 1376834233_thumb.jpg

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Since you struck my curiosity about the RD-77 custom version of the Moog electronics, I decided to have a look at it for you. From what I do see, there will be two separate source follower FETs dedicated to the lead and rhythm pickups respectively. These possibly terminate to the pickup selection switch. Unlike the three way compression/expansion/bright mode switch, I expect this will be changed to a two way normal or bright mode switch selection. Except in these changes that I have now suggested, I cannot foresee any other differences over the RD Artist (proper) when the tone control functionality is incorporated. Only the compression/expansion modes should appear missing.

 

The Caswell electroplating solution I am suggesting uses brush electroplating over a bath method. While I have not tried this technology out yet it, looks very interesting because it appears total unobtrusive to the integrity of the original hardware. This is just an opinion of mind that one may wish to discuss with a proper jeweler over my untried speculation. I am not in any way trying to sell their products for them here nor am I in any way connected with these Caswell products. It just seems like a nice idea to me in a plating restoration application.

 

Sure... I can duplicate such boards but I have "the fear of God in me" over patent infringements with either Moog or Gibson. I will not even try this as a prank!!!! Again, I am not remotely affiliated with either Moog/Gibson folks. If either company wishes me to entertain such work, they can bend my ear. The price of a typical $300-$400 for an original board is not unreasonable. That aside, I am not set up to do this myself.

 

Re-manufacturing such boards in a low lot volume will be this expensive. Since I have two RD Artist boards, I will attempt my changes in the future and maybe report back on this forum at a later date. I do expect my suggested changes will be many orders of an improvement over the original electronics. For example, carbon films will be noisier than metal films. Low noise electronics design is a topic easy enough to research here.

 

Vishay makes a special line of audiophile resistors too but you will not find the exact component values that you will need for the stock design. It is the shielding technique that I have suggested that will be of the most useful benefit. I surmise matching the FETs requires that you only match the Idss of these parts where a 2SK170BL flavor might do quite nicely. Again, this is only speculation at the present time.

 

My advice here is free to read but I stress the utmost caution of duplicating these design(s) and claim any distant co-originality will land one in extremely hot water!!!! Besides.... I am sure one might prefer an original Gibson/Moog re-released part to have any practical value at all? I legally stress only either or possibly both companies only hold the licensing rights to do such work. All the best and take care.

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hello

how did you go with the electronics.

gibson realeased 3 versions of the rd, standard, custom and artist

The 77-78 rd custom has the smaller board. Cant seem to find a schematic (couple low res not very readable)

heres a link

http://www.lespaulforum.com/forum/showthread.php?t=122418

 

Send me a personal email at fabian_hartery@yahoo.ca

 

The forum quota at the present time does not allow me to post this for free. I got the RD Custom schematic from Gibson customer support. Just ask for it and I will sleuth the rest with you. Take care.

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Hi all, 

I was wondering if you could help me restore my 1980 Les Paul Custom Artist. It had the moog electronics removed at one point, admittedly a very tidy job, but very unfortunate. I'm looking to restore it to its original former glory.

Has anyone ever seen a wiring diagram for the Les Paul version, there are two seperate circuit boards. I'll need to link them and wire in the micro switches.

Any help would be greatly appreciated!

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