Knock, knock.......is this a door to heaven? Or how I met MC2205

Meter board is the last one. You can see old caps, ready to be changed:

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And diode across cap:

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Here are the new ones:

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And recapped:

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At this point everything was done, and I have started to reassemble parts. Then I found one more thing that should be done. On thermal protector one leg which accept faston clip was loose, and that was not good. Through that leg goes AC (110 or 220 V) and this connection must be tight. I mean, all connections must be tight. So I have cleaned it and put some solder to make sure that there is no loose connection:

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Now, this is thermal circuit and no soldering should be there, but temperature of thermal cut engage is lower than soldering melting point, so I think that there should not be problems.
 
OK, all is ready for testing. Here is first turn on with one channel, through variac. Ampermeter is in series with AC plug, and voltmeter across emitter resistors.

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All is fine, there is no excessive power draw, and bias is adjusted without any problems, with procedure in user manual.

Now let see how both channels works:

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With both trimmers turn fully ccw I got steady 45,5 W.
Of course, there is a reflection in display from Christmas lights on window, which are still turned on.

After few minutes still 45,5 W:

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I have set bias again on first channel, and you can see that power consumption is increased by 6 W (total of 51 W), and voltage drop at emitter resistors:

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Raising bias on second channel, 6 W (total of 57,5 W) more and voltage drop on resistors:

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After few more minutes:

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Reminds me of double Pink Floyd album 'A nice pair'.

Bias setting was without problems and without sudden increases in voltage drop or current draw.

So, first testing is done, but there are still some things to do.......
 
Final result is here:

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Lower metal bracket has dents and missing paint on some spots. Now it is touched with paint:

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What is left to figure where to place new amp and then listen to some music!

I must say that I have really enjoyed this restoration. It took me a while, almost month and half, but it was well worth every hour. I have tried to take a picture of each step that I was doing and give description. And, of course, that other could see what to expect on this beautiful restoring journey. I am sure that some details could be done better way and there is something that I have missed, but that could always be sorted out.

Electronics is my hobby for last 30 years, and during this and previous restorations, MC2200 and C32, I have learned a lot, from inductive WWs to audio grade capacitors, from decomposed ribbon cables and failing semiconductors, to D shaped potentiometer shafts and chrome polishing. But what I have found most valuable are people on this forum, knowledge and help that is given in this and all other threads.

And I am glad that you liked the title!

I think that I should stop looking at advertising papers for a while if I want to survive living with my better half..................
 
Congrats!!! Looks good all back together. Thanks for taking the time to photograph the progression. I have found it extremely entertaining and useful. Have fun listening!
 
Very happy for you! You will get years of enjoyment from the amp....especially after you hoist the beast into place and herniate a disc!!! The thread reminds me of @Gregory who had a thread called MC2205 love.
 
Thanks for sharing your process and procedures in getting this old girl going. Fantastic job, I always enjoy these restoration threads and yours was especially entertaining and informative. If you risk purchasing another project please share again! :)
 
The thread reminds me of @Gregory who had a thread called MC2205 love.

That series is still up, but all the images are missing because Comcast discontinued their [our] Webspaces a few years back. Rrrr

http://www.audioaficionado.org/showthread.php?t=1102

The photos were nice and sharp.. JPGs exported from processed PNGs


Was thinking of republishing it on AK. The reason for NOT doing so in the beginning was the moderator–aficionado guy war back in those days.. threats and post deletions, etc.

Let's forget that, ok?


-Greg
 
Oh and I would do Gregory's trick of burnishing the brass posts inside the meters and I would replace the gels while you have them out.

You mean filing the brass terminals on the meter wires? Would recommend doing BOTH L&R sides.

I only did the Left meter that was cutting out. It's delicate work so proceed with caution.

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file both sides..

Or cut off and solder new terminals to the wires.


-Greg
 
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As the title says.......knock, knock! It's Mr. postman! I got something for you. Look:

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Me......smiling.....happy.....endlessly.....

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Now all is on it's place:

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Together in electric dreams........:

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For second time in this thread it is hard to find words right now..........
 
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I must say that amp looks and plays wonderful. Today's package in mailbox was really special for me and I thanks Mike and Tony once again. And thank you all for your help, support and comments which really means a lot to me.

Now I have to figure out how to arrange place for both amps due to their weight so I could try bi amping. But these are sweet worries.
 
That sure brought a smile to my face. Glad we could help!

Now you likely own the nicest MC2205 in Croatia!
 
As a new owner of a used MC2205, I feel so proud of you Ivo! And to those who provided help to him along the steps of restoration, what a wonderful trans-Atlantic collaboration we have witnessed! - from a fellow mac fan in South East Asia!
 
Very impressive Ivo what you have done with this beat-up Mc2205.
Like the guys from Wheeler Dealers, you gave this old lady a second life with all your TLC you put into it!
Now I have to do the same with my 2205. Not so much aesthetic work but understanding why it behaves strangely with my lack of technical experience.
 
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