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This is terrible.

HAL9000

HAL9000

i like marantz!!!
I got a marantz 250 3300 set from a friend of mine.

He bought it a few days ago. The buyer said that the set was completely serviced by someone. So everything seemed fine.

however, he connected everything and he heard the strangest noises coming out of the 3300 and 250. He brought the set to me with the question why the hell it's making popping sounds etc.
by further inspection i saw this.

CIMG2798.jpg

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VU L standing in the middle no sound!


VU R no sound and with sound. No reaction.

CIMG2800.jpg


The circus??
CIMG2801.jpg


2 relay forced on each other :thumbsdn:
caps, of al brands (chinese crap)

Left amplifier module has green print and does not belong here.
rubycon caps??, all transistors are displaced. also weird

CIMG2803.jpg


right channel seemd to be O.K
except for the NOS rubycons (new old stock)

CIMG2805.jpg


The wires for the lamp display have been re-done.
all is well but the VU meters are not fixed but loose.
and the Vu meter circuit hasn't been done! old broken caps, and transistors too.

CIMG2807.jpg



TERRIBLE. The 3300 seems 100% but am hearing distortion in Left channel. I don't know if it is the 3300 or the 250.
i haven't tested it yet.


THIS IS NOT HOW YOU SERVICE EQUIPMENT :tears:
 
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Use one channel cable and see if you can isolate which component is doing it. That ceramic power resistor on the left side looks a little crispy?

charles
 
I am sure you are going to fix it!!! :thmbsp::thmbsp: Let us know!!

The stamp "tested" on this unit is kind of crazy...

:beerchug:
 
I see a lot of burntness.....( is that a word? )

The "Hal Machine" can knock this out without working up a sweat..... I look forward to the updates.....


jk
 
I am sure you will get back to top shape Hal. I am also looking forward to the informative updates and great pictures

TC
 
Looks like you have **** cooking on these boards...Cooking transistors make terrible popping noises..
 

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Once finished, you'll be a middle man like this guy.
 

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Its a shame, but all to common so-called techs will butcher a machine or half-ass a repair. I see alot of that - at least 1 machine a week that's been under the knife of an amateur brain surgeon. :no:

I say if you don't know what you're doing - leave it alone. Don't make it worse for the next guy :thumbsdn:
 
I'm an amateur at repair, but I could have done a much better job than that. I HAVE done a better job than that. Geez, get some new transistors and some good quality caps! It never ceases to amaze me the terrible "repair" jobs some people do...
 
I've seen a few horrific "hack jobs", even much worse even than that. I don't know what these people think they are doing. The worst is that often this is done by 'professiona;s' who charge people money for screwing up their gear that way.

I'm an "amateur tech", too... but I make it a point of pride to work carefully and methodically, to do research first (as/when needed), use good materials and tools, etc... and I usually get good results that I'm reasonably proud of. If I do a soldering job that doesn't look good enough to me, and I can't re-flow it nicely, I'll suck it out and start over again. If I have doubts about any component, I'll get a meter out and check it, or replace it. If I'm re-capping, I'll check ALL resistors and transistors, too, and re-mount transistors with fresh grease, etc...

It's just a matter of personal integrity and pride in one's craftsmanship, of having to live with what I've done, every time I look at the gear or use it. If I did 'hack jobs', I'd quit trying to fix anything, if not for my own peace of mind, then for the sake of the gear!

So why can't all 'professionals' do the same? If we were talking about some huge investment of time, I could understand. It would be un-economical. But it takes no more time, really, to install a proper component than a wrong one, or to solder well instead of poorly, etc...

At least this poor, abused example is finally in the hands of someone who will make it all right again. Looking forward to seeing the progress through this thread!
 
Shame.....This one will challenge you HAL. There is a whole list of chit that goes wrong with the 240's and 250's. Let me know if you need any help. Popping is a common symptom for these and usually ends in destruction!!!!
 
paul79 said:
Shame.....This one will challenge you HAL. There is a whole list of chit that goes wrong with the 240's and 250's. Let me know if you need any help. Popping is a common symptom for these and usually ends in destruction!!!!
Click to expand...

yes you can help!!

I'm not getting the right models/types of transistors.
What are the models??

or replacements of.

sps1951
sps1952
2324 ? what is this? sn bc bd by?

i want to identify. print numbers:
Q518
Q517
Q506
Q502 Q501 = differential.


personally, i think differential i going to blow.
i'm seeing the weirdest things on my scope. (old oxidated transistors btw) :scratch2:


any help would be appreacated. :thmbsp:
 
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Nope. Q-501 and 502 is the differential pair.

Sps 1951 and 52 are just small signal transistors.

What's the problem i wonder?
 
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I'll have to bring the 250 manual home with me tomorrow but my money is on the Darlington transistors. Bet you got crazy stuff going on under load right? Loads of distortion? No bias? Also, seing how it is coming out of protect (I assume??)is the kicker. Here are the parts you need to change: MPSA65, MPSA43 are available at Newark, and MPS6519 is un-available but substitute with BC557 (pin-out is the same) available at Digikey. Buy 10 of each or so and replace all of them on both channels. If you have one good channel, swap em out and see!! There is no way that I have found to check them properly so I just change them. Replace all the electrolytics as there is only a hand full in the whole amp.
 
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