I had a little bit of a surprise when I opened up a Marantz 1120 I found at a garbage dump : The whole power amp part was missing and had been adapted with a part from different amps with a mix of output transistors and a rectifier bridge glued to the side of the amp and wired with non insulated coper wire. The faceplate is very clean and after spending a few hours getting all the non original parts out of it and installing the original MR752 rectifier diodes it now works as a preamp.
I would very much love to get it complete and back to original. I already managed to get hold of one pair of sj2519 outputs but I'm still looking for the feet, the whole power amp board, one grill for the output transistors and one pair of sj2519.
If anyone has these parts and wants to sell I'm interested !!
I would very much love to get it complete and back to original. I already managed to get hold of one pair of sj2519 outputs but I'm still looking for the feet, the whole power amp board, one grill for the output transistors and one pair of sj2519.
If anyone has these parts and wants to sell I'm interested !!
I finally found the parts I need to get this amp back to live. It didn't come cheap but it's worth it right 
?
This is how it looked when I first opened it :
The Power amp board should be getting here by november 2nd. Next step will be a total recap and maybe some small signal transistor replacements. No doubt that all the electrolytics will go but are there some film caps that also should be replaced and what would be a good model to replace them with ? The MKT film caps are cracked on the outside, is this in any way a sign of how their insides are doing ?
?This is how it looked when I first opened it :
The Power amp board should be getting here by november 2nd. Next step will be a total recap and maybe some small signal transistor replacements. No doubt that all the electrolytics will go but are there some film caps that also should be replaced and what would be a good model to replace them with ? The MKT film caps are cracked on the outside, is this in any way a sign of how their insides are doing ?
That one should be US made, before manufacturing was shipped off to Japan. I've only been inside one Marantz unit with the FR4 circuit boards but I don't remember which model, it was at least 20 years ago. Good find and good luck! I've been in two US models, I forgot about the 500 I repaired.
Craig
Craig
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Yes it is and I was very happy to find it although a little disappointed when I saw the inside had been messed with.
I decided to replace the ERO MKT caps with panasonic ECW for the .1µF and Vishay MKP1839 for the 1µF, both Polypropylene, the rest will be replaced with Vishay axial caps and some nichicon Fine Gold for the smaller values.
I've been looking around for threads about this amp and found a lot about the caps but not much about the transistors in this amp, it has the original SJ2519 ouputs and all the rest seems original as well according to the schematics. Does anyone know if some of those tend to have a bad reputation or should I just leave them all be if everything turns out to be working ?
I decided to replace the ERO MKT caps with panasonic ECW for the .1µF and Vishay MKP1839 for the 1µF, both Polypropylene, the rest will be replaced with Vishay axial caps and some nichicon Fine Gold for the smaller values.
I've been looking around for threads about this amp and found a lot about the caps but not much about the transistors in this amp, it has the original SJ2519 ouputs and all the rest seems original as well according to the schematics. Does anyone know if some of those tend to have a bad reputation or should I just leave them all be if everything turns out to be working ?
The last US Marantz I worked on was a Model 500 and since it was pre-interweb it was really hard to get info on the SJxxxx parts, doesn't look like the interweb has helped. I still have two SJ2500s and two SJ2501s, both orange grade, Motorola and test good on my analyzer. I don't know if they'll help you though.
Craig
Craig
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