2275 rebuild project

Actually the "+" sign is correct, it's just for the axial cap. The long silkscreened lines indicate the holes for the axial part. It sure would have been NICE if they would have mad the pads and drill hits so that either orientation of cap could use the "+" sign correctly. #*&)(_)(*&%#$!

Yep, while I was praising them for putting in the closely spaced holes, I was cursing them for the somewhat confusing markings. Just curious if anybody knows why Marantz would have added those extra holes? Do other Marantz models use the smaller vertical cap instead of the long axial version?
 
Yep, while I was praising them for putting in the closely spaced holes, I was cursing them for the somewhat confusing markings. Just curious if anybody knows why Marantz would have added those extra holes? Do other Marantz models use the smaller vertical cap instead of the long axial version?
I just assumed it gave them flexibility for component availability. But most of my assumptions end up being wrong.
 
Here's today's progress on the P400 phono board. I made more mistakes on this board than anything before so I'm not sure what that says about my abilities....or lack of same. Regardless, I have an amazing team of folks here to keep me moving in the right direction so here's the original P400 pre-rebuild:

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and here's the rebuilt version:

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and here's a closeup with the fiberglass tubing along with some shrinkwrap. I used the shrink on the top of the pair of diodes because it clung to the wires better than the fiberglass would.

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Here is the breakdown of the parts used with the Mouser part number in parentheses:

P400
C401 - Original - 1uF 25v / Now - 1uF 450v (ECW-FD2W105J)
C402 - same as above
C403 - Original - 47uF 16v / Now - 47uF 16v (UES1C470MPM)
C404 - same as above
C413 - Original - 100uF 35v axial / Now - 270uF 50v radial (EKY-500ETD271MJ16S)
C414 - Original - 1uF 250v / Now - 1uF 450v (ECW-FD2W105J)
C415 - same as above
H405 - Original - 2SC458L,B / Now - KSC1845 (KSC1845FTA)
H406 - same as above
H409 - Original - VD1212 / Now - pair of 1N4148 in series (1N4148)

Question for the experts: Which of the parts that we typically replace on the Marantz receivers is the most heat-sensitive? Since I had to re-install two parts on this board, I was subjecting them to more heat than I wanted especially since I'm using solder braid. I'm trying to keep the heating time down to a minimum but wasn't sure if any of these parts were particularly sensitive.
 
I'm into another 2270, not the same model, but looky at the phono board. I have the radial leaded electrolytic local filter cap already out. The silkscreened "-" sign is even on the correct side for this board layout! :)
King2270_2 002.JPG
 
Glad to do it. I've been going slowly with this one as it's my first rebuild and I usually take a few days off between boards just so I can listen to it. I'm trying to decide which section to tackle next....the big caps or the tone board. I'm also wishing I had a desoldering gun. For example, one of the toughest things I've run into is getting some tiny glob of solder out of the circuit board hole after removing a part. The braid can't seem to reach in and get it so I end up putting another "glob" of solder on the solder pad and pray that capillary action gets it out. I know there's risk involved in using these vacuum desoldering guns, but I feel like I'm doing potential damage to the pads just by having to heat them over and over just to get out some tiny bit of solder.

SO much to learn! ;-)
 
I got a Hakko FR300 as soon as I started this hobby on the recommendation of another member, and it's the best purchase I have made. Removing components from the board takes a few seconds, and once you get the hang of it, there is almost no way you will damage a trace. I know they are not cheap, but if this is going to be an ongoing hobby, they are worth every cent. I have removed hundreds and hundreds of components with mine and the only trace I lifted was when I wiggled a cap I thought was loose and it was still stuck to the trace. I have a technique now that prevents that.
Steve
 
Steve, if you have the ability (and time) to do it, how about a short YouTube video showing how you use your Hakko? I've been thinking about getting the FR300 as well, but unemployment and my horrible finances prevent me from making too many impetuous buying decisions. Could you do a short training video?
 
Steve, if you have the ability (and time) to do it, how about a short YouTube video showing how you use your Hakko? I've been thinking about getting the FR300 as well, but unemployment and my horrible finances prevent me from making too many impetuous buying decisions. Could you do a short training video?

Good idea. I'll see what I can come up with.
 
...one of the toughest things I've run into is getting some tiny glob of solder out of the circuit board hole after removing a part. The braid can't seem to reach in and get it so I end up putting another "glob" of solder on the solder pad and pray that capillary action gets it out...

Effective low-tech solution: use the tip of a round wooden toothpick with the soldering iron on the solder pad to clear the opening.
 
Effective, low-tech and VERY cost effective! I love it, Ben. Thanks.
 
I just use solder braid, rarely, and one of these...
ds017lp.jpg
 
I get the baby steps and the flattened forehead syndrome (from slapping my forehead over mistakes - way too often). But we're getting there. I look forward to the rest of your rebuild, and I think I'll take you up on the offer for a little length of that fiberglass insulation. I'll PM you. Thanks!
Steve
Hello again to the Texan branch of the Tate Family!

So funny about the "FFS"
However I'm on to the mastery level of actually beating mine against the wall.... :-/

I'm just constantly amazed (and appalled) at how many goof-ass little mistakes there are to be made! It's like there's a master checklist that the Cosmos is holding somewhere that must be checked off.. (Note to Cosmos, can we knock it off with the "repeatedly burn self with soldering iron" requirement!?)

Your Tate Brother, Brian
 
I don't see 2275 threads here very often so I hope this will help some of the other newbies like me. All credit has to go to Leestereo for his help with this restoration. I never, ever would have attempted such an extensive project if it wasn't for his offer of help. I know enough about electronics repair to be dangerous despite a lifetime of enjoyment of all things audio. I'll try to keep the updates coming on a regular basis to let you know what I've learned along the way. BTW, I'm firmly in the camp of "If it ain't broke, don't fix it" so this puts me WAY outside my comfort zone. However, this AK forum is SO helpful to folks like me that I know you all won't let me get too far off script.

History
I picked up this 2275 from a guy here in Florida a few months ago. It was mostly functional (noisy controls, burnt out dial light, tuner out of alignment, etc.) and came with a fairly nice wood case. The only odd thing was the power cord which was not original. The seller told me that the original cord had been damaged and had been replaced. I didn't notice at the time (didn't even know to look!) that this was an international model. One of my first posts here was about the odd wiring configuration I found coming off of the transformer which was missing the usual jumper wires. I replaced those jumpers, built my own DBT and held my breath....no problems.

Restoration
As I said, Leestereo was kind enough to help build a spreadsheet for this project. Without his help, I might have done the P800 board, relamped to LED, got the tuner aligned and called it a day. But, with a false sense of security, I've plunged into it all the way.

Before I started the resto, I decided to open up the chassis and poke around. I saw that the original dial lamps had partially melted the plastic housing. So, I got a set of blue LEDs as well as a set of warm whites. The blues were TOO blue, so I opted to install the warm whites. As you can see in the first photo, those WW's had way too much green in their output.
(Also note the face feet....thanks to the AK'er who came up with that one!)


View attachment 795372

Our own dwojo started stocking a new LED called "Pure White" and I just installed a set. It looks blue in this photo but is a very good neutral white color:

View attachment 795373
Blue LEDs were WAY too blue for me so these Neutral Whites are perfect.

P800 Power Supply board
This was the first board I worked on as everybody here sees this board as the "heart" of the Marantz. Here's the original configuration and as you can see, this 2275 was amazingly clean and looked like it had very low hours on it except for the caps getting cooked by the resistor:

View attachment 795393

Here's the P800 after fitting it with the new parts spec'd by Leestereo:

View attachment 795395

Here's the parts list for P800 with Mouser part numbers in parentheses:
C801 - Original 220uF 63v / Now 470uF 63v (UPW1J471MHD3)
C802 - Original 100uF 50v / Now 220uF 50v (UPW1H221MPD)
C804 - Original 22uF 35v / Now 47uF 50v (UPS1H470MED)
C805 - Original 330uF 50v / Now 680 50v (UPW1H681MHD6)
C806 - Original 470uF 16v / Now 470uF 35v (UPW1V471MPD)
C807 - Original 4.7uF 50v / Now 10uF 50v (UPM1H100MDD)
C808 - Original 47uF 16v / Now 47uF 25v (EKY-250ELL470ME11D)
C809 - Original 220uF 10v / Now 220uF 35v (UPJ1V2211MPD6)
H808 - Original DS131B / Dual Diode (BYQ28E-200,127)
H811 - Original DS131B / Dual Diode (BYQ28E-200,127)
R807 - 150 ohm 5 watt / 150 ohm 7 watt (W221500JRLF)
L801 - MY2Z-02-DC22 relay / Now MY2-020DC24 (MY2-02DC24)

Coming up.....P700 power amp boards
Thanks so much for posting this, I'm at about the same progress in my 2275 restore. This has been invaluable!
 
Hello again to the Texan branch of the Tate Family!

So funny about the "FFS"
However I'm on to the mastery level of actually beating mine against the wall.... :-/

I'm just constantly amazed (and appalled) at how many goof-ass little mistakes there are to be made! It's like there's a master checklist that the Cosmos is holding somewhere that must be checked off.. (Note to Cosmos, can we knock it off with the "repeatedly burn self with soldering iron" requirement!?)

Your Tate Brother, Brian
You mean my "other" Tate brother Brian. I might have told you I have a brother named Brian who has Down Syndrome and who lives with me since our parents passed away. He is a real joy.

As for the Cosmos, if you manage to make contact, just tell them ditto for me. Lol.

BTW, looks like we are both working on 2275's along with Dave. Interesting.
Steve . :beerchug:
 
Yeah, where the heck WERE all these 2275's when I started looking for my first Marantz? Glad to be in such good company here!
 
Making mistakes can be a great learning tool. I learned the hard way a few times and it set me in my place. . Experience they call it. The biggest mistake is to be over confident. Being in a hurry and not using a Dbt is one of them.

I have posted lists in the past, of tools and stuff to have that are basic to doing a good job. and also adopting certain habits while working. Stuff i learned. We all find our groove in time. Knowing were your hands are and were your tools are pointing is extremely important.

The day i bought a temp controled soldering station and started using solder braid was a huge advancement for me. Having a protective pad on the bench and using thin .039 solder was another way to eliminate future problems.

Anyone that buys a unit from a butcher, knows the joy of working on a board, that butch Burned the tracks off, by using a old weller soldering gun.
 
Been busy lately with company visiting and other life perils so hope to have the next board done soon. Been very interesting to read Steve's thread about the power supply and the big caps and how to connect them to ground. I'll have to read it again to figure out which method is preferred as those big, blue caps are calling to me for install.

One odd thing popped up today. I had the 2275 on the bench playing FM at low volume and connected my iPhone via the Aux input to listen to a podcast. I hit play on the iPhone and could very faintly hear the podcast leaking into the FM sound. I tried other inputs and it was there on all the inputs....very faint, but there. And, it would increase in level on any of the unused inputs if I raised the volume level on the '75. If I lowered the level coming out of the headphone jack of the iPhone, it would go down in level on the '75s inputs as well. Any idea where I could be getting this bleedover? Rocking the (already cleaned) Source selector switch didn't fix it.
 
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