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McIntosh MC-240 Restoration

Got the last two wires figure out. Had to look very hard on the computer at the digital pictures I took. Schematic also helped. They were the Red wires by golly. They sure aren't red anymore. Ugly brown is more like it.
 
Wires missed on my last 240 swap, 2 that went to the old preamp socket from the power transformer are now unused 6.3V winding.
Click to expand...
Terry, I have three wires that connected to the preamp socket. "X", "Y" and "Z" on my schematic. Looks like it has a center tap. Did you just cut these off and tape the ends since they are now unused?

Also, does anyone know where I can get a couple of these little hardware that secure the tube cage to the chassis?
(Picture lifted from Scott's MC240 thread :D )

MC240cage.jpg


Thanks,
Wes
 
Cut used end from wire, fold over, cover with heat shrink, and tuck away out of sight - thats what I did with the extra unused wires.
 
Well, the MC240 is finally finished. :music: Thanks to all of the forum members who participated in this thread. This was quite a learning experience for me!

mc240-1.jpg


mc240-2.jpg


It came out looking pretty nice. I decided to keep the original finish on the base and transformers. A little polish and wax worked wonders! But the best thing is that the amp worked perfectly on the first try. I powered it up with a variac while monitoring the B+ and bias voltages. Everything was spot-on when the input voltage reached 125VAC. Here's what it looks like on the inside:

mc240-3.jpg


mc240-4.jpg


A few notes for those that may be considering this project:

- The MC240 is complicated. Take as many pictures and draw as many diagrams as you can stand. You will need them to put this thing back together.

- The speaker barrier terminal strips are still available new from sources such as www.mouser.com. They are made by Cinch.

- The cage mounting posts came from www.audioclassics.com. Very nice and speedy service from these folks, even for such a small item.

- The reproduction chassis was easy to work with. All of the holes line up perfectly. The silk screening is a little off near the speaker terminals. So, it's not perfect, but very close. This chassis surely has its origins in Asia somewhere. I hope they (or better yet, McIntosh) would tool up for some of the other amps like the MC275 or MC30.

So, now is the time to pair the MC240 with my MX110 and do some chilling / listening for a change! :music:

So, thanks again to the McIntosh forum members. This thread and project has been fun for me!

Wes
 
Thank you for sharing your restorations with us Wes! I can almost picture the big smile on your face when you are listening to these very nicely restored pieces.


Carl
 
What a fabulous job!! I'm sure your efforts will motivate quite a few of us to get off our duffs and start on one of our own "little" projects!!
 
Beautiful work, Wes. It's amazing what and be done in 2 or 3 hours. :D

Let us know how it sounds with that '110.

Murray
 
C O O L

She looks LOVELY all made up like that :yes: A most deserving component to restore - and one that should give years of future service! NICE WORK!!!

People who restore vintage gears in such fashion have much respect here :ntwrthy:
 
Wes,

I want to compliment you first on this thread and second and most important on your restoration of this beautiful MC240. Thank you.
 
This forum is great for it provides detailed information about the restoration of a piece of MC-240 in a new chassis. Unfortunately, all the pictures provided by the author were removed.
 
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