Worklog: Marantz 2275 Restoration

[aokman]

Worklog: Marantz 2275 Restoration (Complete!)

Hey guys, thought i just scored a Marantz 2275 amp from someones garage that they were going to throw out! and it looks like its going to be a great restoration project

Thought you guys might want to follow along and feel free to offer any pointers along the way

So far problems taken care of:

- Instrument lighting requires replacement - taking the LED route

- Volume control scratchy - deox'd volume pot

- Right channel very very weak - pre out and main in switch link playing up, confirmed with RCA's plugged in, deox'd connectors...

Anyway thats a starting point, ive never tried something like this before with a amp but im going to give it a go and start by stripping it down for a good clean

 

[aokman]

heres the quick update just everyone knows where im up to aswell

Repainted a little of the back where it had faded away

Both channels are working fine now, the internal switch for the main in and preout was oxidized and causing the preamp signal not to be fed back into the amp...

also finished building the bridge rectifier circuit which will supply this Marantz with LED goodness has 2 outputs 1 for the needle which needed some tweaking for brightness and 1 for the 7 blue LED's for the main backlight.



I also managed to pull out the tone board and give it a good clean up i deox'd all the pots and contact switches and contact cleaned the PCB ready for new caps





now i just have to wait a few days for my package of Panasonic FC caps to arrive from digikey...

 

[fwardell]

Great - keep 'em coming. I'm at about the same stage as you on my 2275. what caps did you order or where did you get the information on recapping? My 2275 works so well that I've been putting off recapping.

 

[aokman]

Heres the cap list i ended up with... bear in mind its not a true order i ordered spares for other stuff and a few other things

She already sounds great as is with all the pots cleaned up but im going to recap it anyway given the age of them...

Basically i used a little text document i found on here which was pritty good, i cross referenced it with the service manual to make sure i covered every cap listed in the amp. It does not help that the service manual doesn't list caps if they have polarities or not :nono: other than that hopefully i have everything i need

1 2 P10247-ND CAP 470UF 16V ELECT FC RADIAL 0 0.47000 $0.94
2 2 P11258-ND CAP 330UF 50V ELECT FC RADIAL 0 1.30000 $2.60
3 2 P10347-ND CAP 220UF 63V ELECT FC RADIAL 0 0.90000 $1.80
4 2 P11183-ND CAP 220UF 10V ELECT FC RADIAL 0 0.39000 $0.78
5 2 P10323-ND CAP 100UF 50V ELECT FC RADIAL 0 0.44000 $0.88
6 6 P11196-ND CAP 47UF 16V ELECT FC RADIAL 0 0.34000 $2.04
7 2 P11230-ND CAP 22UF 35V ELECT FC RADIAL 0 0.34000 $0.68
8 12 P11250-ND CAP 10UF 50V ELECT FC RADIAL 0 0.18800 $2.26
9 2 P13197-ND CAP 15000UF 80V ELECT THA 0 23.93000 $47.86
10 1 Z2633-ND RELAY PWR DPDT 5A 24VDC 0 7.26000 $7.26
11 22 P11212-ND CAP 10UF 25V ELECT FC RADIAL 0 0.12500 $2.75
12 2 PF2105-ND CAP 1.0UF 250V METAL POLYPRO 0 0.79000 $1.58
13 26 P10312-ND CAP 1UF 50V ELECT FC RADIAL 0 0.13700 $3.56
14 2 P10294-ND CAP 100UF 35V ELECT FC RADIAL 0 0.38000 $0.76
15 2 P10271-ND CAP 220UF 25V ELECT FC RADIAL 0 0.38000 $0.76
16 2 P11199-ND CAP 220UF 16V ELECT FC RADIAL 0 0.48000 $0.96
17 4 P10290-ND CAP 33UF 35V ELECT FC RADIAL 0 0.34000 $1.36
18 12 P11213-ND CAP 22UF 25V ELECT FC RADIAL 0 0.13700 $1.64
19 16 P10315-ND CAP 4.7UF 50V ELECT FC RADIAL 0 0.13700 $2.19
20 12 P10269-ND CAP 100UF 25V ELECT FC RADIAL 0 0.15300 $1.84
21 2 P11181-ND CAP 100UF 10V ELECT FC RADIAL 0 0.34000 $0.68
22 10 P4540-ND CAP .22UF 63V STACK METAL FILM 0 0.13300 $1.33
23 10 P4671-ND CAP .47UF 50V STACK METAL FILM 0 0.18200 $1.82
24 4 P5560-ND CAP .22UF 50V ELECT NHG RADIAL 0 0.24000 $0.96
25 2 P10296-ND CAP 220UF 35V ELECT FC RADIAL 0 0.48000 $0.96
26 2 P10776-ND CAP 100UF 100V ELECT FC RADIAL 0 1.01000 $2.02
27 10 P10314-ND CAP 3.3UF 50V ELECT FC RADIAL 0 0.13700 $1.37
28 10 P1175-ND CAP ELECT 4.7UF 25V SU BI-POLAR 0 0.15300 $1.53
29 2 P1195-ND CAP ELECT .47UF 50V SU BI-POLAR 0 0.24000 $0.48
30 5 478-1890-ND CAP TANTALUM 3.3UF 35V 10% RAD 0 0.65000 $3.25
31 5 478-1834-ND CAP TANTALUM 1UF 25V 10% RAD 0 0.46000 $2.30

 

[jstang]

Ditch the Tantalums....

jk

 

[aokman]

yup ive heard that aswell ive ordered electrolytics also i just grabbed some tantalums from digikey while i was ordering just to make sure i have all parts incase i run into any problems :thmbsp: im just hoping there isnt a cap in there that is bipolar that ive missed from the manual :scratch2:

will find out anyway when they arrive from fedex and i can pull the rest of the boards out, wish they all popped out as easy as the tone board did with the connector

 

[Sir.Byrd]

yup ive heard that aswell ive ordered electrolytics also i just grabbed some tantalums from digikey while i was ordering just to make sure i have all parts incase i run into any problems :thmbsp: im just hoping there isnt a cap in there that is bipolar that ive missed from the manual :scratch2:

will find out anyway when they arrive from fedex and i can pull the rest of the boards out, wish they all popped out as easy as the tone board did with the connector

Double check for bipolars.
Also, you might want to cross-check your list with the actual unit, Marantz SMs suck for being accurate for any given unit.

 

[Yankee Dog]

I'll be watching this closely, I have a 2275 that needs a recap, just can't get the time. Is the cap list (text document) you mentioned the one that Catrafter submitted?

If so, it should be pretty accurate. Are you changing all the electrolytics? Another thought, maybe while it is apart, change out the older losssy ceramic filters for maybe 180's. It will be a big benefit. YD

 

[aokman]

I'll be watching this closely, I have a 2275 that needs a recap, just can't get the time. Is the cap list (text document) you mentioned the one that Catrafter submitted?

If so, it should be pretty accurate. Are you changing all the electrolytics? Another thought, maybe while it is apart, change out the older losssy ceramic filters for maybe 180's. It will be a big benefit. YD

yeah i think that is the one, seems ok but i referred to the service manual also. Yeah im replacing all the elctrolytics and i can have a look at the filters and stuff when i have all the boards out i guess :scratch2: have to say i didn't actually consider them yet?

 

[onepixel]

Very nice save and looks like your going to do a very thorough job with the restoration on one very excellent Marantz!

 

[catrafter]

Ditch the Tantalums....

jk

+1:yes:

That's not my list, mine is not as comprehensive.
Use at your own risk, YMMV, etc.
Tom

 

[aokman]

got bored this afternoon and decided to get the annoying bit out of the way which is refinishing the faceplate....

Sanded the scratches out of the face and blended it in with the existing finish - filed and refinished the bezel sides from where the amp has been smacked into things also

heres a quick piccie of the results, ill get more detailed ones shortly

expecting mr fedex with my caps tomorrow

before:



after:

 

[Yankee Dog]

Looks good. You have more guts than I!

Mine has some faint nicks and scratches in the face plate, even a name lightly etched in the upper left corner, but, while I am familiar with refinishing (polishing) aluminum, I never did anything but clean the faceplate. I am concerned with damaging the anodizing to the face plate which could lead to discoloration to the face plate in the future from oxidization.

Not sure if it is even a problem, but...YD

 

[catrafter]

Here's a more complete cap list, courtesy of PacificStereo.

Tom

 

[Yankee Dog]

Nice!:thmbsp:

 

[aokman]

Well Santa just dropped off his sack of capacitors for me and i got cracking with the tone board

heres a pic of how it went anyway, all the electrolytics are done and all the tantalums are done. Anyone else have any suggestions for replacement parts on the tone board before i move on :yes:

which ceramic filters where you referring to also

 

[Yankee Dog]

Man, is that board clean! Looks good. Thoroughly enjoying (and saving) this thread. YD

 

[sssmokin99]

Error in service manual!

When you get finished and are ready to adjust the bias and offset, make sure you are using the correct pins. I believe the service manual is WRONG - do a search and find out the correct pins to use- it has been mentioned on here before. I'm not at home right now or I would look at mine and tell you- but I remember there was an error there. ( and maybe some other parts of the manual, as well)!

 

[aokman]

Todays work so far:

P800 board has been stripped of caps and relay - washed the board down and removed PCB glue, replaced all caps with Panasonic FC series - replaced relay with new part and also replaced the insulator for the tranny





yeah i think my service manual has had those bits crossed out and the correct meter points put in aswell i must double check also need to redo the R806 on the P800 board as i knocked it a bit while cleaning

 

[ZeroG]

Amazing transformation!
Could you tell us what you used to remove the glue?