Marantz 18 Transistors

[mech986]

You guys might want to contact Tom Ishimoto at Northridge Electronics. He was former service manager at Marantz during the 70s and 80s and also helped design some of the last big power amps there in the 70s. He probably would know what to sub in if he will share that info with you (or repair for you or your client).

http://northridgeelectronics.com/

 

[tonebells]

SN# 18-5591 right channel would not bias up more that .07 volts. I replaced q10 34-1003 2N5195 and Q9 34-1002 2N5192 and it came up with room to spare.

Tony

 

[tonebells]

I added some info to post #18. http://www.audiokarma.org/forums/index.php?threads/marantz-18-transistors.852971/#post-12500933

Tony

 

[RV59]

my contribution:

Q11, Q14, M 34-1000: 2N3055
Q12, Q13, M 34-1001: MJ2955
Q1, Q2, Q4, Q5, M 34-1014: 2N3568 KSC945C
Q3, Q6, M 34-1013: 2N3638 KSA733C
Q605: M 34-1012: (fet) 2N5460

Transistors scope: 2SC2611

 

[Widzew83rts]

Hi

Where can i get transistors for Marantz18. 34 1013 and 34 1014?

 

[tonebells]

SN 18-4416 distorted left channel. I could pick up the distortion all the way from the input of the driver board to the output. Replaced Q7/Q8 and all was clear.

Tony

 

[Ray122]

Any recommendations for replacements for the diodes CR-1203, CR1202, and CR1201 on the scope display board?
Part numbers for CR-1201 and 1202 are 35-1004 and the part number for CR1203 is 35-1014

Thanks!

 

[EricB1983]

After running the new caps in for a week with zero issues, I turned my 18 off last night then turned it on when I got up this morning. After about ten minutes on, kept getting a loud popping noise from the right channel. Tracked it down to Q804 (which are 34-1010 on the parts list) on the Tone Amplifier board. Came here to find subs, and after going back and forth across several threads I tried a matched pair of KSC1845F and it's back to working normal. Hope this helps someone.