Marantz 3800 Op-Amp Replacements

[goldswimmerb]

Hi, so I saw this thread here and figure I would try it.

I did have some additional questions for any of the experts:
Would an OPA134PA work as a replacement for the LM301 chips in this amplifier? I noticed one of my 301's was replaced with something else and wanted to make sure that I could just drop in something modern. It looks like I should be able to just drop in a 134, but wanted to be 100% certain.

 

[Salty Guy]

Will this work as direct replacement???

https://www.ebay.com/itm/Ersatz-fur...ganic&brand=Revox&_trksid=p5411.c100167.m2940

 

[goldswimmerb]

Will this work as direct replacement???

https://www.ebay.com/itm/Ersatz-fur-ICs-uA739-uA749-A739-A749-mit-LME49720/174093728779?_trkparms=aid=1110006&algo=HOMESPLICE.SIM&ao=1&asc=20140131123730&meid=2b117cdd73c04722a489a551be035877&pid=100167&rk=3&rkt=13&sd=174073947546&itm=174093728779&pmt=0&noa=1&pg=5411&algv=DefaultOrganic&brand=Revox&_trksid=p5411.c100167.m2940

That's a good find, would probably work though unsure of the actual op amp they're using.

 

[Salty Guy]

The Marantz 3800 uses the ua749PC.

I ended up ordering this one instead...

https://www.ebay.com/itm/UA749PC-Se...187449?hash=item5b6ac2fc79:g:~2wAAOSwowdc-jk8

WHAT YOU THINK? ARE THEY ALL THE SAME? MAKE ANY DIFFERENCE? I'm just replacing parts, and not very knowledgeable.
Any help or input would be greatly appreciated.

 

[Mika.T_FIN]

Can anyone say what op amp can be used to replace a burnt lm301?

 

[goldswimmerb]

Can anyone say what op amp can be used to replace a burnt lm301?

opa134 is what I used and it worked well, just make sure your supply voltages are in line. You may have to change the dropper resistor to get it in spec in some units.

Though, the LM301 being burnt up likely points to another serious issue.

 

[jcat8s]

Hi, im looking for the selector switch bank or the phono 1 switch for the 3800...i have heard the 3600, has the same bank...please let me know, and have a great one