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Marantz Service Manual error thread

Raccoon1400 said:
The correction for the bias procedure for the 2245 appears to be missing, it was there before I thought.
10mV between pins 754 and 760
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I have 2245 that shows rail voltage on pins indicated in service manual. If schematic is correct J753 is emitter and J754 is collector of the output, so 35v is correct there.
J754 and J760 according to same schematic is measured across both output collectors. Is 10mv correct target?
Also, how long should amp be powered on and idling before considering the measurements? I let it idle for about 20 minutes and backed it down from 13mv to 10mv. I do check/correct DC whenever I touch Idle current. 15 minutes later one channel was 11mv and another went down to 8mv. I re-adjusted to 10mv and turned it off. I want to see what will happen as it warms-up again.
 
Going through a Marantz 3200 pre. Hearing noise after shutdown. The relay on the output board grounds the outputs (and other inputs to output board) when de-energized. The schematic only shows one channel's ground path through the relay:
3200 schematic.png
The PCB layout shows both channels going to the relay:
3200 PCB.png
 
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The 2238 (not B) manual identifies Q804 as the 2SC945 transistor and Q806 as the SIB01-02 diode, but I believe they are switched around on the board. The 2252 (not B) has the same issue.
 
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Although I've posted this before, I scanned in a copy of the 2270 manual and converted it all to readable text using OCR software and used the best circuit diagram scans I could find and made them into Word & PDF docs. I've also corrected some (but not all) the errors that were found in this post. Using this you should be able to make a "correct" 2270 manual.Here is the link..
https://1drv.ms/f/s!AulYHAx4JToPaA0ARopgvLMJHmM
 
bluehills5 said:
Although I've posted this before, I scanned in a copy of the 2270 manual and converted it all to readable text using OCR software and used the best circuit diagram scans I could find and made them into Word & PDF docs. I've also corrected some (but not all) the errors that were found in this post. Using this you should be able to make a "correct" 2270 manual.Here is the link..
https://1drv.ms/f/s!AulYHAx4JToPaA0ARopgvLMJHmM
Click to expand...

Looks great!

Tony
 
Thanks so much bluehills5! It is great to be able to search documents. If you ever do any others I would love to have them. Right now have a 2245 that is causing aging me.
 
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Lately I was working on a 2226. I found some typos in the schematics I downloaded from HIFIENGINE. On one C809 is with + to R802 and on the other it is with the negative ti the R802. From experience I can say that negative is to R802 and polarity is printed correctly on the board.
IMG_20190408_195339[2].jpg
IMG_20190408_195325[2].jpg
 
I wonder how many Marantz's are in the graveyard from inaccurate service manuals? I suppose it was better in the 70's than it is today. I hate getting instructions written in an Asian language. My Cantonese is weak. On the other hand schematics are schematics (i think).
 
More manuals other than the 2270? Probably not. I went down this rabbit hole scanning a few pages and converting them to text and before long I'd done too much to back out but was starting to realize the extent of the project. The text scanning is fine but the component tables with the Greek characters all get interpreted by the OCR software as Latin ones (mu looks like u to OCR software) or they are randomly scrambled and all needed to be manually checked & changed. Then the formatting so the page numbers remain the same as the original manual requires futzing with font size, spacing and sometimes just adding blank lines. Originally I wanted to use the MS Word index feature so you could jump to the chapter you need but gave up but if someone wants to do this, please feel free. Oh- and the cover page has an optional black-on-white version as the original white-on-black was hell on my inkjet printer.
 
I feel your pain because I did this same thing with a 35 page document years ago when OCR was -not so much. The goal was to make it searchable. I ran into several issues much like you describe and went in and manually changed them. It was a monumental task. Thank you for what you did. In the 90's I set up an OCR scanner for a company and it scanned 15 pages a minute, accuracy was not too bad (within its own parameters) and it would pull data and drop it in a spreadsheet etc. Hard to believe but true. It was for a State/Fed agency so they had unlimited funding. Nobody had seen one except the people before me who tried to figure it out. The learning curve on that thing was steep ha. It still causes sleepless nights. The manual (over a hundred pages of super small print) that came with it was written by the Japanese engineers that designed it and their translation skills where less than perfect. Lots of trial and error.
 
Marantz 1050
The service manual parts list and schematic show C801 as 470uF but a 330uF cap is fitted to the board.
 
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Klaatu561 said:
Yikes- That's one for the Marantz Gurus. Same voltage?
Click to expand...

Yes, 50V.

The SM covers both the 1050 and 1072 models. The parts list shows many differences in transistors and resistors between the two while the main board has a different part number too. However, all the capacitor references are exactly the same. Makes me wonder if the 1072 had a 447uF cap at C801 but that's been accidentaly transposed in the manual to cover both models.

I'm 99.9% sure that the 330uF cap is original as it's an old grey Elna and has still got the same brown brown goo fixing it to the board as the filter caps.
 
Well not sure this paste is of much use and probably something you already know. I am almost sure someone out here will know. The question was (research)-- Can I use a higher capacitance but the same voltage capacitor in my speedometer cluster gauge? Like a 10 uF 25 volt capacitor replacing a 6.8 uF 25 voltage capacitor? My first thought (that shows my ignorance) was sure- why not. Here is the paste of the response.
-----It will depend on how the capacitor is being used. If it is part of an averaging circuit then the answer is no. The capacitance change may change the input to output ratio and the speedometer may read too high. It is usually acceptable in circuits where the capacitor is being used as a filter to use a larger capacitance and the same or higher voltage. Remember that the voltage listed is just the limit of what the capacitor can tolerate before it begins to fail. -------
 
AngelAT said:
Lately I was working on a 2226. I found some typos in the schematics I downloaded from HIFIENGINE. On one C809 is with + to R802 and on the other it is with the negative ti the R802. From experience I can say that negative is to R802 and polarity is printed correctly on the board.
View attachment 1473243
View attachment 1473244
Click to expand...
Umm, I think the schematic on top is correct and the bottom one is wrong. This is due to the polarity of the diode. If you have the 2226 still measure the voltage with the probes right on the pins, negative probe to the negative pin and so on.
 
Descrepancies with the Marantz 2265B service manual I ran across while doing a rebuild.....

- PE01 Pre / Tone Amp Circuit Board: Capacitor CE40 polarity shown backwards on circuit board silk screen. Polarity shown correctly on schematic.

- P200 Tuner Circuit Board: In general, the schematic and circuit board layout in manual doesn’t match what was installed from the factory.

- P700 Main Amp Circuit Board: Siamesed transistors Q756/Q758 incorrectly identified as Q766/Q760 on right channel circuit board silk screen

- P700 Main Amp Circuit Board: Capacitors C718/C768 & C719/C769 shown as 0.1 uF in manual but replaced by jumpers from the factory.

- P700 Main Amp Circuit Board: The following component values shown in the service manual are different from what was installed from the factory:

· R729/R779 & R733/R783, 200 ohm called out, 300 ohm factory installed
· R730/R780 & R734/R784, 160 ohm called out, 300 ohm factory installed
· R731/R781 & R735/R785, 300 ohm called out, 820 ohm factory installed
· R732/R782 & R736/R786, 2.4K ohm called out, 1.6K ohm factory installed
· R737/R787, 36K ohm called out, 43K ohm factory installed
 
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