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Marantz Service Manual error thread

full amp rebuild of a 2240, the SM from hifi-E has in the schematic portion C704 is correctly listed as a 47uF-50v. But they do not indicate polarity. It is polarized and if you look at the SM and turned it on its side to read it properly, the + side is at the 'top' and it connects between R712 and R715
 
2220B C301 10uF missing polarity on board markings. The positive goes to R306 towards the chip.
 
For the Marantz 2270, R771 and R772 on the P750 power amp boards, there is a mismatch between the parts actually installed vs. what is shown on the SM parts list and schematic.

My unit (S/N 58763) has this mismatch and I have also seen a couple of other posts on AK that note the same thing: As-built R771-R772 are 20 kohms (red black orange gold) on both P750 boards, while Parts list and Schematic call for 27 kohms. Guessing it was a production change?
 
For the Marantz 2252B, there is an error on the P700 Main Amp and Power supply board schematic. The resistor labeled R726, 0.1 Ohm/200W should be labelled R762, 10 Ohm/2W, the counterpart to R761 for the other channel. The parts list for R762 is correct.

Also, on the same P700 board, the electrolytic capacitor C705, 47uF/16V is mislabeled on the schematic as C707.
 
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Marantz 2252B, CE23 and CE24 should be 1uF/50V, +/-20% Non-Polarized electrolytic capacitors as marked on the schematic, but not in the parts list.
Also, C721 on the board layout shows incorrect capacitor polarity (+), board silkscreen is correct orientation (opposite from layout).
 
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Not sure if this is the right place for this but has anyone had any experience with the PM 94 service manual, particularly the idle current adjustment section? I downloaded the manual from Hifi Engine and it looks like there are at least a couple of typos but I am not an electronics expert.

I recently aquired a PM94, it sounds very sweet but seems to be running very cool for class A so was going to check the various settings. However after looking at the SM I am a bit nervous about touching anything until I can get verification that the manual is correct (or otherwise).
 
Integrated Amp 1150 SM says
Power supply adjustment J805 and J810 adjust J815 to 44VDC, OK
Power supply adjustment J816 and J810 adjust J816 to -44VDC, NO.
There is no J816, it should read J806.
Power supply adjustment J806 and J810 adjust J816 to -44VDC, OK.

First time I've seen a Marantz that wasn't 35VDC on a single adjuster.
You adjust each rail on these. Cool!
 
2220B/2230B/maybe others:
This one is not an "error" per se, but it is at least a marginal part spec: R805 is rated at 2W. It has 21V across it 100% of the time, which is 1.33W. It gets HOT. Maybe a better idea to use 3W or larger.
 
The 2230b manual shows a shunt capacitor across R739 and R789, on the P700 board, (obviously). The value is .01 uF. This is in fact soldered to the back of the PCB.
 
2270 Service Manual P300 MPX Board
Found this on the P300 Board Assembly. Have not seen these in this thread so i thought I'd post.
No callout for L302
No callout for H302
H302 has callouts for E and C reversed on the board assembly. E should be toward the board edge connecting to R307, R319, C goes to R354. Transistor is installed correctly
Audiokarma has been a great help with my 2270 restoration SN 22314. (still in progress).
Thanks to all who have contributed to this amazing forum.​
 
I've been rebuilding the P700 of a 2330B. What a mess! Q709 on the schematic and layout show Q709 as being 739! I was chasing my tail! (I'm trained in electronics to an entry level). I went to DeVry and graduated in '81. But, I never worked in electronics in my professional career. I ended up programming CNC machinery for 15-20 years then transitioned to ITIL v 4 doing Change Management, so I never really had a, "Career" in electronics. But, I decided to rebuild the power supply as well as the output stage of my 1979 2330B. I was shocked at how the schematics/parts layout differed from the actual board!

I can tell you that in the, "official", service manual, The drivers on one channel are way off! The board numbering differs from the official schematic. What they show is Q786 on the schematic is actually Q709 on the board. If you have a 2330B, take your time and correct the errors before you start toasting output transistors. Ask me how I know. :D
 
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Need accurate silk screen diagram for 2330B...

My 2330B service manual has numerous errors for the 2330B P700 silk screen. Some are quire glaring. Some of the errors include:

Q738 is actually Q709
Q759 is actually Q739
Q721 is actually Q741...(This one is wrong on the schematic as well as the silk screen. The P700 schematic show both a transistor AND the thermistor as Q739).

Does anybody have an updated/fixed silk screen? I noticed there is a complete P700 board available on eBay, (minus parts) and it seems to be 100% accurate according to my existing P700 module. Whoever designed that board must have gotten the correct info from somewhere. Unless they just copied an existing board. Any help would be appreciated. It would make troubleshooting much easier!
 
A couple things for the 2330B P700 board...


First, all of the 330pF disc caps listed in the SM should actually be 2200 pF. There are 4 of them and they are all 2200pF; C718, c719, C737 and C738.
C745 and C748 are on the back side of the PCB. You'll see them in the schematic but won't see them in the parts list as it stops at C742. These are the same as C714, etc; .1 uF Film capacitor
R747 and R707 are 1/4 watt 470 ohm and are on the back of the PCB. Again, they're not in the parts list.
 
2330B - Incorrect resistor power ratings...

I don't have a complete list but there are multiple, (at least 10) resistors on the P700 that are rated at 1/4 watt in the parts list when they clearly aren't. Easily recognizable as they're on ceramic stand-offs. I found this out the hard way.
 
I stop by this thread when I have a Marantz on the bench, search says no 1040 SM errors.

BUT WAIT!

R741 mislabeled as R759.
 
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Marantz M-250-3 Service Bulletin.

There are no service bulletins specifically for the 250M. The 250 and 250M are essentially the same power amplifier aside from the different meters, so service bulletins for both amps are listed as for the 250. (The M in 250M stands for 'modified'.)

This service bulletin states it is for serial numbers above 6549. It was assumed that Marantz would continue on in sequence with serial numbers for the 250M. Unfortunately, Marantz reset the serial numbers for the 250M back to the beginning. This can be confusing.

So if you are working on a 250M, assume that this bulletin is for all model 250M amplifiers in addition to model 250 amplifiers above 6549.
 
1180 DC in P700 Main Amp there is CT01 on the right hand of service manual, in left hand C602, it should be CT02 right? CMIIW
 
Jailtime said:
Help us out! If you've run across anything that's wrong in the Marantz service manuals, post it!
Click to expand...
I have a Marantz 2330. The service manual doesn't show C720 or C721 on the schematics of the Amp Board (P700) and the parts list only mentions C720 (220pf) but not C721. Can anyone clarify this?
 
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