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marantzfan's 4400 - All Out Restoration!

ChrisMarantz said:
I hate it when that happens :saywhat:
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I hate it too. Got 32V on the DC offset test points, outputs and main drivers are OK. Emitter resistors are OK too. Checked wiring and board edge connectors. Tough problem to track down.

marantzfan said:
I have the utmost confidence that Kyle will get things sorted out and be back with more news soon. :yes:
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Thanks. It's nice to have these substitute outputs for troubleshooting. :yes:
 
Nose back to the grindstone. :D With the help of catrafter, looks like the root of the amp board problem was found. H735 diode had a bad joint. Testing results coming soon.

I rebuilt the phono board today. Finally an easy task in the 4400. Just 3 'lytic caps and two tantalums. Elna Silmic II for the 'lytics, Panasonic ECQ-V films for the tants. A nice Sprague axial was also installed. The board just folds right out when you remove its mounting screws, just be careful with the insulating paper under there.
 

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Jailtime said:
Nose back to the grindstone. :D With the help of catrafter, looks like the root of the amp board problem was found. H735 diode had a bad joint. Testing results coming soon.

I rebuilt the phono board today. Finally an easy task in the 4400. Just 3 'lytic caps and two tantalums. Elna Silmic II for the 'lytics, Panasonic ECQ-V films for the tants. A nice Sprague axial was also installed. The board just folds right out when you remove its mounting screws, just be careful with the insulating paper under there.
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I'm glad you were able to find the fault with the amp board, I know how frustrating it can be.

The phone board looks simple, what looks scary is the tangle of wires next to the board. :yikes:
 
ChrisMarantz said:
The phone board looks simple, what looks scary is the tangle of wires next to the board. :yikes:
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That's the selector and Dolby switches. Good thing there's no parts to replace hidden in that tangle. :yes:

The phono board is simple enough that I missed a VD 1212 diode by the pots. Guess the board is coming back out.
 
Hey Kyle, I'm glad to see you back in the saddle again on this one. I hate to see anyone struggle on a project. Especially when you're in the lime light! I bet you'll have this producing good, good, good, good vibrations soon! Jerry
 
EXCELLENT POST!!

I am going to be doing this as well and I was wondering if it is possible to get a copy of the parts list(s) from Mouser that you used?
I am going to be building an order too.
Also, I'm playing hell trying to find those EPCOS axials...or anything close to that temp. in the same price range. Mouser only stocks the Vishay's at over $17.00 ea.!
Thanx!!
Bud
 
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Here is the parts list from Digikey. The 1000uF EPCOS axial is line number 11 on the list. The Vishay axials for the amp section are line number 15. All the handy part numbers and quantities are right there in the list for you. :D I only ordered relays and small signal transistors from Mouser.
 

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Well, I was ready to pull the trigger on the parts order with Digikey (thanx again Jailtime!) but I need to do some more investigating.
Seems that some parts are N/A (lines #5, 22 & 29 in your list) and some duplicates #'s 25 & 29.
I was think I found a suitable replacement for #5 using Digikey # 493-1332-ND. I have found some CDE brand ones (338-3338-ND for the .47UF and 338-3331-ND for the 1.0Uf one but they are rated up to 85C) but I am still trying to find the poly stacked caps. Any suggestions on what to cross those Panasonic ones with?
Thanx,
Bud
 
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69sixpackbee said:
I have found some CDE brand ones (338-3338-ND for the .47UF and 338-3331-ND for the 1.0Uf one but they are rated up to 85C) but I am still trying to find the poly stacked caps.
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Those CDE films should be just fine, I wouldn't worry about the temp rating.
 
4400 update - Amp sections installed, bias and offset adjusted. All channels sound great using my DAC direct to main in jacks.

Tone control board is in work now, being a bit of a PITA with low volume on two of the channels. Gonna break out the scope tomorrow for some signal tracing fun. :D
 
Jailtime said:
4400 update - Amp sections installed, bias and offset adjusted. All channels sound great using my DAC direct to main in jacks.

Tone control board is in work now, being a bit of a PITA with low volume on two of the channels. Gonna break out the scope tomorrow for some signal tracing fun. :D
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Fets show up?
 
On the tone board, where the pots are, I've had issues with the transistors on that board...
 
marantzfan said:
Good God Kyle, will anything with this receiver be easy? :no:
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I don't think so, but it's getting close to done now. Dolby unit is gonna be the worst of it that's left. Amp section sounds great, at least! :D

bktheking said:
Fets show up?
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Not yet.

ManyMoonsAudio said:
On the tone board, where the pots are, I've had issues with the transistors on that board...
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That's where my issue is, it seems. I have good equal signal from the 4 outputs of PE01 preamp board. The signal gets really weak on a couple channels in PF01 tone control. I should have equal signals from PF01 to that little daughter board PD01, correct?

EDIT: Looks like the transistors on that PF01 tone control are 2SK30s, which I'm gonna have 4 of. Those are for the scope amp though. Dammit.
 
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