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marantzfan's 4400 - All Out Restoration!

WOW, I wish I had the skills you have.

I took my 4400 apart the other day to remove the tip of a headphone jack that broke off into the FRONT headphone jack. It was a pain in the butt to get that tip out of there. Had to remove the jack and take it completely apart to get tip out. But, I did get it back together and its working great again.

I was pretty proud. But, now I see someone with some great skills. Good luck. Wish I could apprectice with you while you do this restoration.
 
Hey, Jailtime,
The amount of work you are doing, is that the "norm" for a resto?
The reason I ask is because I got a real nice unit and it plays great and all functions work. At the very least I was going to do just the PS and change out the big filter caps as well. I see, however, you have gone that "extra mile" and all I can say is I'm dooly impressed to sya the least. But, since I lack the equipment, i.e; scope, etc, it is hard for me to send a trace signal down the line and really scope it out...pun intended.
In your "expert opinion", what is the very least I should do beside the aforementioned?
Also, can you briefly "explain" the caps you put across the filters alongside the bleeder resistors?

Thanx again for helping me along the way with your excellent post!

BTW, Marantzfan is one lucky dude to have your utmost attention to detail instilled in his resto.

Thanx! :thmbsp:

Bud
 
For a full restoration, yes, what I'm doing is normal. I'm even coming up a bit short on this one, not gonna do the tuner boards. I lack the experience to fix the tuner if I was to screw it up.

It all depends on what you want. Do you just want peace of mind that a receiver isn't gonna blow up in your face? Or do you want it to perform as well or better than original?

4400s run the power supply board very hard. Rebuilding it will get you that peace of mind that things won't go downhill real fast. If you're not gonna go whole hog, I'd do the PS, and clean all the connectors. Check all the bias and offset voltages. LED lamps would save the housing from further frying. I didn't really notice other areas in the 4400 where caps were subjected to excessive heat.

Those film caps across the filters are bypass caps. They're basically a filter that has the ability to charge and discharge quickly. They can improve high frequency performance. I think they look cool too. :D
 
Jailtime said:
Those film caps across the filters are bypass caps. They're basically a filter that has the ability to charge and discharge quickly. They can improve high frequency performance. I think they look cool too. :D
Click to expand...
Any preference for the stacked films??

Looks great!

Thanx,
Bud
 
Jailtime said:
I think I used Panasonic ECQ-V, 3.3uF 250V. They just fit.
Click to expand...

Nope...don't come in 250V versions. I think it's this one:

P10985-ND CAP FILM 3.3UF 250VDC RADIAL $1.36 (Panasonic ECQ-E series 0.819" L x 0.413" W (20.80mm x 10.50mm))

Thanx !
 
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This tone control board (PF01) is killin' me. I have good signal on all four channels from PE01 preamp board. Input from PE01 to PF01 is good. Somewhere in PF01, I'm losing signal to two of the channels. The section with the 2SK30s is good. I didn't replace anything on PF01, except the 4 10uF caps, which pass signal correctly. The board worked before, so I have no idea why it's wrong now.

It looks to me like signal passes through PF01 tone control before it heads to the PD01 tone amp. I did recap PD01. Possible that a mistake there is messing up what I see on PF01?
 
Bad cap? Wrong polarity?What about the diodes on that board? Is there signal coming out of the FETS? Fets don't like heat, so maybe a pair blew. Did the 5 I sent ever arrive?
 
Kyle,
If you don't have it, go to hifiengine and download the 4400 owner's manual. It has a really nice block diagram that might help narrow down the problem.

I'll bet your arms are tired from flipping that big bugger over on the bench.

Tom
 
Nice work Kyle......all this is Greek to me :sigh: ......can't wait for the final outcome. :yes:
 
I wish I had sufficiently encouraging words for you...the 4400 is a mess inside, and the schematic is a nightmare to behold. Marantz seemingly went out of their way with the construction and documentation on many of their units to make them as service-unfriendly as possible.

Many of the boards had to endure a lot of gymnastics to get to the solder side while replacing caps. Don't discount a broken wire or a wire-wrap post that now has its solder pad busted loose.
 
bktheking said:
Bad cap? Wrong polarity?What about the diodes on that board? Is there signal coming out of the FETS? Fets don't like heat, so maybe a pair blew. Did the 5 I sent ever arrive?
Click to expand...

The only caps on PF01 tone control that I replaced are the 10uF lytics. They are just coupling caps off those FETs. The signal looks good off the FETs and those caps. The ones you sent did arrive, thanks! :thmbsp:

catrafter said:
Kyle,
If you don't have it, go to hifiengine and download the 4400 owner's manual. It has a really nice block diagram that might help narrow down the problem.

I'll bet your arms are tired from flipping that big bugger over on the bench.

Tom
Click to expand...

Got it, I had the signal flow right. From PE01 buffer/preamp to PF01 tone control to PD01 tone amp. So the problem is definitely in that PF01. Input from PE01 is good, the output from PF01 is wrong on two of the channels.

I don't flip this 4400 over at all, got it standing on a side. :D

EchoWars said:
I wish I had sufficiently encouraging words for you...the 4400 is a mess inside, and the schematic is a nightmare to behold. Marantz seemingly went out of their way with the construction and documentation on many of their units to make them as service-unfriendly as possible.

Many of the boards had to endure a lot of gymnastics to get to the solder side while replacing caps. Don't discount a broken wire or a wire-wrap post that now has its solder pad busted loose.
Click to expand...

Yeah, it's dreadful to trace 4 different signals through this preamp/tone section.

I just don't know where something went wrong. I'm pretty sure there's no broken wires, I have good input to the board, at least from PE01. I didn't do any work on the section that's bad now, it worked previously. There's not really any sensitive components in the tone control board, just resistors, film caps, and pots.
 
Kyle,
Sorry for the delay in response to your PM.

The transistors I mentioned being problematic before are indeed on the short PD01 board. Even if you think the signal is getting past, replace all 8 of the transistors on that board with some low noise transistors.

If for no other reason, base it on my experience with having two 4400's with a problem here..

Other than that, It's gotta be something that happened while working on it...

I've been down deep in more of these than I care to have been... Just a PITA receiver with a whole lotta parts....but for some reason, they sound pretty good.
 
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ManyMoonsAudio said:
The transistors I mentioned being problematic before are indeed on the short PD01 board. Even if you think the signal is getting past, replace all 8 of the transistors on that board with some low noise transistors.

If for no other reason, base it on my experience with having two 4400's with a problem here.
Click to expand...

So you think it's possible that PD01 is messing with the signal on PF01? I'll give it a shot, because I really don't have much to go on right now. Time to order more parts.
 
From the schematic, the PD01 appears to be a sort of daughter-board to the PF01, in that signals are passed to the PD01, shuffled off through JD01~JD04 to God knows where (following the wiring gives me a migraine), and then back to the FET's on PF01.
 
I replaced the transistors on PD01, hard wired the joints from PD01 to PF01 to eliminate the possibility of a bad joint, and reflowed/resoldered joints on PF01. Same problem still there, low signal on two of the channels.
 
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