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Marantz Transistor/Diode/Trimmer Sub Guide

R762 is a 2.2k on both. R782 on this 2245 schematic from hifiengine.com is not shown as variable. I guess a little investigation is needed. But R762 is the trimmer for DC offset. R782 looks like a carbon comp resistor. Not sure why it shows as variable on your schematics.
Marantz 2245 main amp.PNG
Marantz 2245 main amp2.PNG
 
Thanks! I see now that on a 2245, R762 is 2.2K ohm, and there appears to be (4) more trimmers at R783 and R782 that are adjustable. It doesn't help that Page 27 from the 2245 SM is missing, which would cover those trimmers in detail.

Qp22qqq.jpg


Thanks again for keeping this all in order!
 
I just noticed, the High Res 2270 schematic, found here in the AK DB, shows it has 4 trimmers per P750 board, the two arrows I marked at R762, R763, but then also at R782 and R783 (same place as 2245):
97Uo5C3.jpg
 
Steven Tate said:
Well, I did another data dive and compiled a fairly comprehensive list of 99% of the transistors and diodes used in 70's era Marantz stereo integrated amps and receivers. I scanned threads until I was blue in the face, and scanned the internet for specs. I searched every Service Manual to pull a list of transistors and diodes. I looked for recommended subs throughout the threads, and collected the ones that were repeated often, or that someone had successfully used. I can't be sure of the appropriateness of any of the listed subs, but these are the ones I would start with if I were looking for a sub. I tried to search for availability, and only use subs I could find. Many recommendations that I came across turned out to be obsolete. I'm hoping the gurus will take a little time to scan for obvious problem suggestions, or to fill in blanks where I couldn't find any info. Please let me know if you find errors or have better suggestions for any sub. So, here is a link to the Excel spreadsheet on my Google Drive and I am attaching a PDF for those that don't have Excel handy. Give me suggestions on how to improve my list! Search for your transistor or diode in the left column (alpha order), and look for subs in the columns to the right.
Spreadsheet:
https://drive.google.com/file/d/11a0YpNoHxK-PQYfmikAL3U10215_ocn7/view?usp=sharing
Click to expand...
Thank you soo much just saved me a ton of work. Repairing a Marantz 5400 recording deck.
 
zedex said:
Nice Steven. I printed that off. Thats a heap of work saved for anyone looking to replace transistors/diodes.
Click to expand...
I've asked one mod to make it and the Marantz Control Cross Reference sticky, but no response one way or another. I think both documents can save a ton of time.
 
Absolutely. Even suppliers are scratching their heads when it comes to subs. I was on the phone for an hour with mouser for only 3 transistors. :) I sure appreciate it.
 
MarantzRefrb said:
Could we please have this be a sticky? Could we also please have someone be appointed to sticky items in the Marantz forum, for the future?
@Grumpy, @RayW, @Negotiableterms

Thanks!
Click to expand...
@Grumpy, @RayW, @Negotiableterms - Please! And while we're at it, this Marantz Control Cross Reference could be a great sticky reference. Both took a lot of time to compile for the purpose of preventing having to do a lot of research in the middle of a rebuild. Thanks!
https://audiokarma.org/forums/index.php?threads/marantz-control-cross-reference-spreadsheet.923978/
 
Well, I'm the least competent person to respond (I'm the administrative guy, like legal and tax stuff), but I think I managed to stick both threads. If I got it wrong, someone let me know, please?

Also, Ray, if you don't want them stuck, reverse course, please!
 
Well done, thank you! It took Steven Tate a considerable amount of effort to compile all of this, and it's something most of us here will need in the future, or have already used many times. Thanks to you both! :thumbsup:
 
MarantzRefrb said:
Is there a known replacement for diode 1N60?
Click to expand...
Depends on what it is used for, and the circuit it is in. Many times a 1N270 will work satisfactorily. Germanium diodes are long out of production. Sometimes certain Shottky diodes will work fine too. Although you can find some genuine NOS 1N60 and 1N60P, as well as 1N34 and 1N34A germanium. I have a small stash of 1N60 for those "just in case" times.
 
Skywatcher said:
Depends on what it is used for, and the circuit it is in. Many times a 1N270 will work satisfactorily. Germanium diodes are long out of production. Sometimes certain Shottky diodes will work fine too. Although you can find some genuine NOS 1N60 and 1N60P, as well as 1N34 and 1N34A germanium. I have a small stash of 1N60 for those "just in case" times.
Click to expand...
I got a small stash of 1N60's at Mike's Electronic Parts.
https://www.mikeselectronicparts.com/product/1n60/
 
Steve. Thanks for all your work on this. No doubt it will be the go to list for the foreseeable future.
I also think it speaks to how much people are willing to help each other on this site. I have been on other sites where you ask a question and you get completely flamed by the responses. Here, on AudioKarma, my experience has been that most people are willing to give their input and help you as much as they can. Great work again!! :music:
 
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