ton4eff

Active Member
Hi, I bought this Marantz 1060 "in perfectly working condition" ;) recently. Don't ask for the price I paid :eek:. What I saw inside however, was a P700 board devastated by some “criminal” and a baked transformer (you know the smell). As you can see from the pictures, there are lots of burnt spots on the board, broken traces and burned insulation paper of the transformer. All transistor were replaced with unknown "things", missing heat-sinks for driver transistors along with the plastic bases for them, missing screws etc... And all this awful solder job...
20151031_162657_zpsithumk8w.jpg

20151031_164638_zpsxuwp3c6s.jpg

Long story short: I decided to rebuild the unit, as close to the original as it's possible, starting from the P700 board. I drew new schematic in the PCB editor (attached below in PDF format) and did a 3d model (not finished yet) for the future board. I have yet to see how to recreate these nice curved fat traces, as they are on the original P700 board. For this project I don't like modern "sterile" 45/90deg. angles. And maybe it's important for the sound too.
20151031_1623311_zpslnloygys.jpg

During the drawing I noticed, that the P700 board is the same for 1060 and 1030 models. The schematic is 99% the same as in the 2230 model. The only difference is swapping of values for some resistors - R713, R721 in 1060 and R758, R759 in 2230 (and the other channel accordingly). As you can see in the schematic attached I made a few minor corrections:
1. Added C705 and C706 - missing in my copy of the schematic for the 1060 and present on the PCB and on the schematic for 1030.
2. Corrected value for C711, C712 from 1uF to 10uF.
3. Corrected designators for C729, C730 -> C723, C724.
4. Bumped value for C703 and C704 to 220uF.

And here I have an important question: On the PCB there is no place for R759 and R760. May be they were soldered on the back side and removed by someone? Or they simply didn't installed in the factory?

And here is the unfinished yet 3d model of P700 board:

P700%20-%20PCB%203D_zpsfskgpqbh.jpg
 

Attachments

  • P700.pdf
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I have two 1060's and a 1030. There are several differences in resistor values on the amplifier boards between the two. The resistors on the back side are on some and not on others. Changes in production runs I guess. It looks like one of the resistors is still there, one is missing.
 
All of those fat curved traces were done by hand by somebody who cared. I had a friend who made circuit boards from pictures of circuit boards in service manuals.
Sometimes he would upscale them to go from surface mount to thru-hole. It can be done, it just took time.

Now, the traces on an SP1200 are on the other end of the spectrum.
SP12003.jpg
 
I have two 1060's and a 1030. There are several differences in resistor values on the amplifier boards between the two. The resistors on the back side are on some and not on others. Changes in production runs I guess. It looks like one of the resistors is still there, one is missing.
Yep.....Working on a 2nd 1060. Changes in he Production run I see also.
 
I had a friend who made circuit boards from pictures of circuit boards in service manuals.

That's exactly what I did to match the holes for the parts on their exact places. I imported the P700 pdf from SM in Adobe Illustrator, scaled it to exact size for the PCB - 150/100mm, adjusted the opacity about 50% and copied the hole places on a new layer. Then exported the DWG file from that layer to the PCB Editor and from there placing the parts is very easy job. :) Actually I'm planning to use the same technique for the tracks too... As you can see from the picture, they match perfectly:
Matching%20holes_zpseornv91o.jpg


Looks great! Are you using eagle?
Thanks. I'm using Altium and if one has the libraries for the parts it's not very difficult job to do.

Changes in he Production run
I was going to make a place on the pcb for R759, 760, but decided not to. I'll try these on the back side when the board is ready and see how it sounds...
 
See the black spots - they are like coal. And smells like these. Somebody replaced the fuse with a very thick wire...:crazy:
I will rewind it, but after the board is finished. I really want that little fellow in perfect working condition, here in Europe they are pretty difficult to find and I like the sound of his cousin 2230 very much. I have a little progress with the curved tracks by the way, it turns pretty well in Adobe Illustrator:
Traces%20Illustrator_zpsfbqd2hxt.jpg
 
And today I managed to finish drawing the tracks layer. Here is the picture still blended above 1030 and 1060's P700 layers. Please comment if you notice any errors. Next thing - importing in the PCB Editor...
1060%20p700%20illustrator_zpscrwx7bme.jpg
 
What a huge headache was importing the dwg files from AI in Altium... And it was slo-o-w. But now the gerber and drill files are ready and sent to the local pcb house:
Gerber%20and%20Drill%20P700_zps8k5pjzim.jpg


3D model is also finished:
P700%203D%20finished_zpsggfnnuwk.jpg


The P700 Board should be ready by the mid January. Now is the time to order some parts...
 
I bought some cheаp MJ15024G and guess what, they are fake. :( Notice the small (3x3mm) dies:
20151212_104822_zps1ptybfwx.jpg

And it was very easy to wash the markings with acetone. I'll place the order for all semiconductors and capacitors to uk.farnel. Is the BAT41 a proper replacement for the 1N60 (H715-H718)?
 
"Looks OK so far..." I disagree, it looks awesome!! I would have just laid it out again in AutoCad myself instead of going through so much work.
 
I am sure there will be at least a few takers for a 2270 amp board, if you make one.

I may try to do this one, just for practicing the technique... But first, I have to finish my 1060.


"Looks OK so far..." I disagree, it looks awesome!! I would have just laid it out again in AutoCad myself instead of going through so much work.

Actually I was lazy and did only one half of the board and then mirror copied to the other half... ;) Is there a way to export gerber files from AutoCad?

The PCB house did a very good job too. The board is FR-4, 2mm tick, 70µm copper and Ni-Au finish.
And if I may ask again, since I didn't order the parts yet, is the BAT41 a proper replacement for the 1n60? This is the only one I have doubts for?
 
There is, look up EasyGerb.

I have heard of using the BAT41 diodes but haven't done so myself. I recommend recycling the 1N60's or use 1N270's if you have any of those. Oh, if I could back in time and stock up on parts!! Of course grab a Hemi 'Cuda and store it. :(
 
Thanks very much for the suggestions. All four original 1n60's show different voltage drop on my DMM from 0.150 to 0.500. AFAIR, it should be about 0.300V for germanium diodes? Tomorrow I'll try to measure them with my old Russian analog (arrow type) multi-meter at the work.
 
Two of my 1N60's appears to be fine, passed the test. I ordered some from the eBay, the guy says that they are NOS and genuine. We'll see...
And here is the board, populated with some parts:
P700.jpg

Lots of discrepancies of the resistor values with the SM. Compared with the pictures of the P700 board from the internet, there is the list:
R707, 708: 18K (SM) -> 33K on the board!!!? What a huge difference!?
R715, 716: 2.2K (SM) -> 2.4K on the board
R717, 718: 150K (SM) -> 120K on the board
R755, 756: 27K (SM) -> 39K on the board
By the way, in my 2230 (the amplifier schematic is the same, as in the 1060), the actual values on the boards are the same as in the SM (I checked) and it works perfectly well.:dunno:
Recycled the ceramic caps, trimmers, and above mentioned resistors, because I ordered according the SM...
And every part is measured twice, before and after soldering to the board. :p
P700 Bot.jpg
And I noticed, that they use the same board in 2215 also.
 
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