Help needed with Marantz 2225 Reciever

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Hello, new member here. I am having trouble figuring out what is going on with this receiver I've been working on for awhile now.

It's not passing signal past the tone board's 1st transistor and voltages are off on the tone caps board, especially that first transistor. I've replaced the first transistors on both channels and no change really.

It has a sort of loud crackley distorted sound when the volume is turned up, but it is almost impossible to tell it's anything music related through the noisiness . It's only a in and out crackling output. I have recapped the power supply board, and everything was at their correct voltages on that board.

What could be the issue?
 
BEFORE you made any changes, did it work? I assume you have the service manual (available at HiFiengine for free).
What are the voltages on HE01,HE02,HE03 and HE04? Those are on the Tone Amplifier Assembly (PE01). Passive
components CAN change though rarely do but if the Voltages are wrong SOMETHING changed. I don't know your
skill level with a soldering tool so "shotgunning" the resistors and caps might make things worse. It's always better
figure it out from the symptoms as you learn troubleshooting skills and minimal potential damage.
 
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In front of the tone amp: Volume and Balance pots, getting signal from TapeMonitor (& Mono) switch, from source selector switch (= PreOut). Check all of these.
Inputcap of tone circuit is a 0μ22/50 (CE01 & CE02), to replace.
 

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Hello, new member here. I am having trouble figuring out what is going on with this receiver I've been working on for awhile now.

It's not passing signal past the tone board's 1st transistor and voltages are off on the tone caps board, especially that first transistor. I've replaced the first transistors on both channels and no change really.

It has a sort of loud crackley distorted sound when the volume is turned up, but it is almost impossible to tell it's anything music related through the noisiness . It's only a in and out crackling output. I have recapped the power supply board, and everything was at their correct voltages on that board.

What could be the issue?

Check all voltages on PE01 in accordance with scheme No. 4 fig2
 
Okay, so I've tested the voltages on the transistors and this is what they were

HE01: E-0 C-31.5v B-0
HE02: E-0 C-31.5v B-0
HE03: E-31.66v C-0 B-31.58v
HE04: E-31.66v C-0 B-31.58v
HE05: E-0.4v C-11.4v B-0.9v
HE06: E-0.4v C-11.1v B-0.9v
HE07: E-12.5v C-0.4v B-11.8v
HE08: E-11.4 C-0.4v B-11.1v
 
In front of the tone amp: Volume and Balance pots, getting signal from TapeMonitor (& Mono) switch, from source selector switch (= PreOut). Check all of these.
Inputcap of tone circuit is a 0μ22/50 (CE01 & CE02), to replace.

According to the manual, CE01 and CE02 are 0.22 uF 50V film caps. Do you really think those are a problem?
Over 40 years I've seen countless 'lytics go open, 1 or 2 short out, maybe 6 ceramics short out and not a single
film cap failure. Given we do not know how good he is with a soldering iron, it possibly does more harm than good
considering the film cap failure rate.

I haven't worked on Marantz consumer stuff in a long time and I don't know Marantz had a problem with
PCBs but I did own a Sony CD player that had circuit board failure where there was no obvious break in the
tracks but some of them were open. It would not take very long to "ohm out" all the traces connected to
the first 4 transistors. They are probably fine but when things get as weird as this, it's worth grasping at a
few straws.

 
I pulled HE03/04 and tested them and they both showed proper hfe and what not. The 01/02 both tested fine, but I had replacements for their type on hand and installed to see if they would work them to no avail.

I've been working on tube equipment for close to ten years so I can solder okay. I really don't like rebuilding traces on boards, but does that sound like the culprit?

There's no obvious burned resistors or exploded cap guts. I should ad that I have clear audio tracing through my phono pre/tape monitor/volume and up onto the board. I believe the caps were passing audio and it was just stopped at the first transistor stage.
 
I pulled HE03/04 and tested them and they both showed proper hfe and what not. The 01/02 both tested fine, but I had replacements for their type on hand and installed to see if they would work them to no avail.

I've been working on tube equipment for close to ten years so I can solder okay. I really don't like rebuilding traces on boards, but does that sound like the culprit?

There's no obvious burned resistors or exploded cap guts. I should ad that I have clear audio tracing through my phono pre/tape monitor/volume and up onto the board. I believe the caps were passing audio and it was just stopped at the first transistor stage.

PCB failures are very rare but NOT impossible. I was looking at the power levels on the resistors and it is so low
compared to the ratings that unless something acidic spilled on the board I would not expect any failures from
'burn out'. You have something weird going on that might benefit from an"out of the box" approach.

Tube soldering is a little different as tube sockets and terminal strips are more tolerant of too much heat.
PCBs CAN be temperature finicky. I had an old Sony monitor a couple years back that lifted pads with a 700°
tip but were OK with 600°. BTW I use a Metcal so the temps are correct.

 
Okay, so good news is RE07 was blown and replacing it brought me back to having bias and now I am getting sound all the way through the reciever.

The sound I am getting through is distorted. Do I need to replace the transistors that ran without bias? Would they have been damaged enough to cause distortion?
 
"Where exactly could the distortion be coming from?" Hard to say without knowing what it looks like.
The test signal shape can point out a lot of problems by knowing how it started and what it morphed in to.
Sine waves, ramps, square waves can all be revealing. Please don't say you don't have a test generator
because you do have one. The sound card in the PC can be an excellent signal generator. I use Adobe
Audition 3 to do that but Audacity can do that also. Thinking about it, Audacity could be your scope as
well BUT I do not know if you can play AND record simultaneously. If you have a second PC then you can
do anything you want. OR you could make the test signals, burn them to a CD and use the CD player as
your test generator. Not many people here do NOT have the needed gear.

Thinking more on this, I have Dell PC at work and its analog audio output was SO BAD I had a hard time
telling a 1 KHz square wave. An external DAC solved the problem but the average guy could get really
confused from the Dell. My Gigabyte boards with Realtek CODECs work exactly as expected.

Make some test signals and capture wave forms and show them to us.

 
I do have a sine/square wave generator but I do not have an oscilloscope set up and working. I have a BK Precision that's been nonfunctional since I have owned it and I have a Tektronix 535A that is supposed to be functional, but I'm not looking to turn that space heater on in the middle of August.

Is there any way with signal tracing and voltage double checks to figure out what components are causing the issue.

One common issue that I have heard is that the tantalum caps tend to fail and cause a crackling noise, but this distortion sounds more like audio stages are overdriving.
 
Bump

Is there anyone that can help? I've been trying everything.

It's incredibly distorted now, and the power amp adjustment is somehow not working and I am seeing no voltage across the pins J714 J716 on now after it was showing over 52 mv and the adjustment pots didn't have any effect on the voltage at all.

This is a project I have been working on someone, and I really would like to get it out of my space. I have no idea where to go now/what to check now as I usually deal with tube equipment.
 
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