Marantz 2500 Refurb
- Thread starter rBuckner
- Start date
2nd the comment on 48vdc relays. Have several stored away as they do seem to come and go from the usual supply houses. Waiting for the tunnel disassembly
Thanks for sharing btw.
Yeah, me neither! :jawdrop:
anderslober
Yikes...not again!
Great work! Reg. the relay...there is a german fellow on german ebay who sells direct plug-in relays............not cheap though........17-18euro + s/h..........I bought a couple from him when I did my 2500.
marantzfan
...
Just noticed that you're located in Prescott, just up the road from me. Hey neighbor. :wave:
The 48V relay came in and has been installed. I put the scope tube back in to fire the 2500 up for a test and am glad to report that it is working fine. I was thinking the scope display was not right when I initially tested it, couldn't get it to adjust right. Now it's brighter so I turned the brightness down and the dot centers up with the pots right about at their center and I can adjust the focus. It has a nice diagonal line for mono and the "cotton candy" as bktheking aptly puts it for stereo. Sweeeeet! :yes:
So it's on to some other board next, likely the humongous tuner all-in-one board. It's about 5" x 10" but the electrolytic cap count isn't too bad. Stay tuned!
So it's on to some other board next, likely the humongous tuner all-in-one board. It's about 5" x 10" but the electrolytic cap count isn't too bad. Stay tuned!
I am going for the tuner board next so went to work getting some access as it is wired in place.
First I took the shield plate off from behind it. First there are two clips with 3 screws each holding the top side. Then there are 3 screws on the top and 3 more on the bottom holding the board on. There's two screws in the back attching it to some mounting clamps. Here's the shield.
These are the two top clamps.
Now the back of the board is exposed.
The two mounting brackets were removed from the chassis.
The scope tube and it's amp board came back out. I also loosened the small board (FM noise amp) to the top left to allow the tuner board more movement. The dial cord has been wrapped at least twice over with foil to protect it from the soldering iron.
Back around the other side the caps have been marked red for replacement.
With stuff out of the way I decided to also remove the screws and pull up this board for recapping, it is the PC01 FM buffer amp. I'll do it first and put it back. There's some tantalums that will get changed out too.
All ready to go in the next session!
First I took the shield plate off from behind it. First there are two clips with 3 screws each holding the top side. Then there are 3 screws on the top and 3 more on the bottom holding the board on. There's two screws in the back attching it to some mounting clamps. Here's the shield.
These are the two top clamps.
Now the back of the board is exposed.
The two mounting brackets were removed from the chassis.
The scope tube and it's amp board came back out. I also loosened the small board (FM noise amp) to the top left to allow the tuner board more movement. The dial cord has been wrapped at least twice over with foil to protect it from the soldering iron.
Back around the other side the caps have been marked red for replacement.
With stuff out of the way I decided to also remove the screws and pull up this board for recapping, it is the PC01 FM buffer amp. I'll do it first and put it back. There's some tantalums that will get changed out too.
All ready to go in the next session!
Tube Sound
Super Member
Great job of sharing the rebuild. Your images are awesome. Thanks for taking the time. :yes:
Thanks [blush] and you're welcome!
More fun this evening as the tone control and filter amp boards were pulled loose from the front panel.
To make up for the PITA tuner board, these two unplug totally. This is the filter amp board.
...and the tone control amp baord, still plugged in to get a picture of the connectors and their wire colors. It was recapped this evening, at least the electrolytics were. I think I ought to look into some Wima film caps for this board and the filter board as well on a receiver of this magnitude.
Easy to work on now!
The filter amp board has been recapped here and this is the spot to spray the DeOxit in to clean the switches.
This cute little fella is the scope input amp board, I pulled it out to get at the pot to clean it.
I forgot to post the most swollen cap to date, found on the tuner board. It's like a tick about to pop!
This is why I prefer a total recap, not to start a war on the old "If it ain't broke don't fix it" subject!
More fun this evening as the tone control and filter amp boards were pulled loose from the front panel.
To make up for the PITA tuner board, these two unplug totally. This is the filter amp board.
...and the tone control amp baord, still plugged in to get a picture of the connectors and their wire colors. It was recapped this evening, at least the electrolytics were. I think I ought to look into some Wima film caps for this board and the filter board as well on a receiver of this magnitude.
Easy to work on now!
The filter amp board has been recapped here and this is the spot to spray the DeOxit in to clean the switches.
This cute little fella is the scope input amp board, I pulled it out to get at the pot to clean it.
I forgot to post the most swollen cap to date, found on the tuner board. It's like a tick about to pop!
This is why I prefer a total recap, not to start a war on the old "If it ain't broke don't fix it" subject!
Baron K Rool
Well-Known Member
I think you should connect that cap to a 17V supply... in reverse!
Another delay incurred as I did decide to source polypropylene caps for the tone control board. What pain! I used Wima where they had the values and Kemet for the others. It took hours of looking to make the list and get it all ordered. Parts should be here Tuesday or Wedsnesday.
I decided to attack the two other boards attached to the front panel. These are on the left or in my pictures below are at the bottom. They are the switch board (tape mon and scope input select) and the selector/phono pre. I couldn't figure out how to get at them without taking the front chassis panel off so I taped the dial cord down to the pullies and did it. The switching board ties to the phono pre board via a vertical (with the chassis in it's normal position) pc board which also has the dubbing jacks.
The phono pre has some of those nice removable connectors but there's also a bunch of wiring wrapped / soldered to the board directly! So I had to recap it in place. What a nasty job some of those boogers were! It's done and loosely put back together pending the other boards I was waiting on parts for. Shot the switches up with DeOxit and also put a bit on each connection pin even though they looked very nice. I sure hope to avoid having to take it back apart!!
Here's the front chassis panel loose and pulled to the side.
The two boards to be serviced.
The "top" side view of the mess.
The dubbing jack board pulled off of the upper switch board.
Reference shot taken to identify connectors/wire colors. I take these just in case my hand drawings are hard to use when it's time to reconnect.
Another reference shot, the phono pre is the lower board. Yeah, it's tight in there.
The phono pre has some of those nice removable connectors but there's also a bunch of wiring wrapped / soldered to the board directly! So I had to recap it in place. What a nasty job some of those boogers were! It's done and loosely put back together pending the other boards I was waiting on parts for. Shot the switches up with DeOxit and also put a bit on each connection pin even though they looked very nice. I sure hope to avoid having to take it back apart!!
Here's the front chassis panel loose and pulled to the side.
The two boards to be serviced.
The "top" side view of the mess.
The dubbing jack board pulled off of the upper switch board.
Reference shot taken to identify connectors/wire colors. I take these just in case my hand drawings are hard to use when it's time to reconnect.
Another reference shot, the phono pre is the lower board. Yeah, it's tight in there.