My try at a Really Nice Rebuild Marantz 2245 2270

You are a gentleman and a scholar Pat.
Thank you very much
Gonna order this weekend and hopefully get it done next weekend.
I'm hoping the tantalums have gone bad and are causing the noise. Cause a cold solder joint could be anywhere
Even better that I can order it all from mouser
 
You are a gentleman and a scholar Pat.
Thank you very much
Gonna order this weekend and hopefully get it done next weekend.
I'm hoping the tantalums have gone bad and are causing the noise. Cause a cold solder joint could be anywhere
Even better that I can order it all from mouser

Good luck, let us know how you make out!
 
Fantastic pat!
I know this is a bit delayed but finally found time at my buddy's shop and we did the advised changes. Problem solved and it sounds excellent.

The only issue i had was i lost(or forgot to order the 22uf/16V electrolytics to replace the tantalums.
But i had a pair of panny 22/35V electros and i used those instead.
Hopefully that doesn't cause any issues down the line. You don't think it would do you? As of now, the first 15 minutes, its sounds awesome.

Thank you!
 
Fantastic pat!
I know this is a bit delayed but finally found time at my buddy's shop and we did the advised changes. Problem solved and it sounds excellent.

The only issue i had was i lost(or forgot to order the 22uf/16V electrolytics to replace the tantalums.
But i had a pair of panny 22/35V electros and i used those instead.
Hopefully that doesn't cause any issues down the line. You don't think it would do you? As of now, the first 15 minutes, its sounds awesome.

Thank you!

You are good to go! I am glad it all turned out well, 22uf 35V is fine.
 
Really owe it to you for finally being able to enjoy vinyl on my favorite amp.
We've recapped and restored the power supply board.
We enjoying getting away, drinking a couple beers, listening to music and tinkering with the thing.
I Have the 2 main filter caps. Will put them in soon.

Where would you go next?
Amp or preamp/tone?
I will say the tone board would be much easier it seems. Not having to monkey with the heat sinks and all.
 
Really owe it to you for finally being able to enjoy vinyl on my favorite amp.
We've recapped and restored the power supply board.
We enjoying getting away, drinking a couple beers, listening to music and tinkering with the thing.
I Have the 2 main filter caps. Will put them in soon.

Where would you go next?
Amp or preamp/tone?
I will say the tone board would be much easier it seems. Not having to monkey with the heat sinks and all.

Pre board next would be good, for some reason I always do the amp boards last. You just have to take your time and be careful, not many caps to replace on the amp boards so not really that bad at all.
 
Pat,

I'm going through my 2245 and I'm having difficulty figuring out how to remove the 700 board with the least amount damage. It has tight wires top and bottom that don't allow access to the back side.

You appear to have removed yours a couple of times. What is your technique? Do you de-solder the wires form the pins?

Best Regards,
Mike
 
Pat,

I'm going through my 2245 and I'm having difficulty figuring out how to remove the 700 board with the least amount damage. It has tight wires top and bottom that don't allow access to the back side.

You appear to have removed yours a couple of times. What is your technique? Do you de-solder the wires form the pins?

Best Regards,
Mike

Hi Mike, I never de-solder a board, they can all be worked on. It may be tight but you can flip it over. You may have to cut some of the plastic type wire ties to free up the wires for more movement, but yes the board flips over. Let me know if this helps you.
 
Pat,

After reading your advice I looked at it differently and realized I could flip it if I unscrewed the terminal strip from the chassis that some wires were connected to. That and I bent one wire bundle retaining finger out of the way.

Thanks for your help.

Mike

P700FlippedandMarked_zps13f5c4a0.jpg
 
Also when you are done check all wires, I had the white one on the end break off, then again I recapped that board more then a couple times!
 
Hi, what replacement transistor you recomend for SJ2513 and SJ2514?

I did not replace mine they were ok.

If needed I beleive you can use OnSemi MJ21195/MJ21196, maybe someone that actually installed these in a 2245 can chime in so we will know it works, before you just go ahead and do it. I know they work in the 2270.
 
Hi Pat,
I've enjoyed reading all your great threads. They inspired me to refurbish my 2270 receiver. I have finished all the boards,(all e-caps with Silmic II) except the amp boards. I see that you replaced the diff transistors. Did you replace these just for the heck of it or did the originals measure poorly? I was wondering also if these are two per amp side and are both NPN based on the Mouser link you gave. So it would be two pair or 4 each total for both amp boards, correct? Also, I'm strongly considering replacing the trim pots on the boards with the Bourns from Mouser. I don't have a dim lamp tester. If I put these Bourns in and pre-rotated them all the way counter-clockwise, would this be safe to power on the amp to adjust them to the 10mvdc setting? Thanks for your consideration.

Sherod
 
For the diff pairs by a bunch because they need to be/should be hfe matched. As far as the trimmers go, after I clean/deoxit a receiver I do make sure the adjustments are holding steady, if they are I leave them alone.
 
I have checked the settings about 4 times now on R763 and R763 and each time the settings have changed. Of course that could be because with each check, I have replaced caps on different boards, so that might have something to do with it. What bugs me is just the slightest touch of the pots makes the numbers go haywire. I was wondering if this was normal.
 
Sorry, I should have proof-read my last post better. For R762 DC offset, it wasn't too bad. I got it close to 0, but it deviated back and forth by 1/10 or so on the meter.
The most sensitive pot was the R763(both channels) when adjusting idle current. This is the pot that would vary the numbers wildly by just barely touching the pot dial. I was able to get the correct reading of 10mv after a 30 min. warm-up, but up until then it would want to continue to climb. After about 30 min. it finally settled at 10mv but the meter would flicker back and forth even then by a point or two. Are the pots okay?
 
That is normal for the idle current, I usually hook up my test leads and walk a way for a bit, because it will slowly move up as things warm up and balance out. So if you wait 30 mins and then can set it, you are fine. Moving by a point or 2 no big deal, I would say you are ok.





Sorry, I should have proof-read my last post better. For R762 DC offset, it wasn't too bad. I got it close to 0, but it deviated back and forth by 1/10 or so on the meter.
The most sensitive pot was the R763(both channels) when adjusting idle current. This is the pot that would vary the numbers wildly by just barely touching the pot dial. I was able to get the correct reading of 10mv after a 30 min. warm-up, but up until then it would want to continue to climb. After about 30 min. it finally settled at 10mv but the meter would flicker back and forth even then by a point or two. Are the pots okay?
 
Yeah- and I wasn't done reading it. Thought I was losing my mind- I kept going back and refreshing the page... Wth?
 
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