Marantz 18 receiver needs help

[bigdrums925]

checking the .pdf I can see it does not show the amendments I made
So what do I need to do to have the .pdf reflect the changes?
Also: can you tell me how to delete or edit or select a value I've added to the schematic?

I have the service manual for this unit but believe it's too big to upload- I'll try again as it contains more accurate drawings
Nope it says failed to upload

[bigdrums925]

Tried downloading a pdf printer to file program which hasn't worked to allow me to post a pdf version of the KiCad .sch file I added the voltages to.
Don't know what to do at this point.
Filling in the voltages reveled an area around Q1, Q3, Q4 with many 0.0 v. Obviously something wrong there
I will try checking Q3, Q4 but Marantz part numbers and no help from them so I don't know what to do if they are bad....

[Jazz P Bass]

Try "Cute Pdf Writer".

CutePDF :: Product :: CutePDF Writer

[bigdrums925]

OK so took Q3 & Q4 out and tested. Q4 is good but Q3 is bad. Marantz part # 34-1013.
How can I find a replacement since this is a proprietary # and Marantz is no help at all?

I got Cute PDF and here is the result:

Upload failed
Damn!

[nickb]

Tried downloading a pdf printer to file program which hasn't worked to allow me to post a pdf version of the KiCad .sch file I added the voltages to.
Don't know what to do at this point.
Filling in the voltages reveled an area around Q1, Q3, Q4 with many 0.0 v. Obviously something wrong there
I will try checking Q3, Q4 but Marantz part numbers and no help from them so I don't know what to do if they are bad....

As Jazz says Cute PDf will work. If you are on a recent Windows 7 or 10 it comes with a pdf printer "Microsoft Print to PDF"

See https://answers.microsoft.com/en-us/...3-92345d6e25df

[The Dude]

OK so took Q3 & Q4 out and tested. Q4 is good but Q3 is bad. Marantz part # 34-1013.
How can I find a replacement since this is a proprietary # and Marantz is no help at all?

Is there not a generic number on the device itself?

[bigdrums925]

No printing on the transistor is same as schematic 34-1013
716 follows that Marantz # however

[nickb]

OK so took Q3 & Q4 out and tested. Q4 is good but Q3 is bad. Marantz part # 34-1013.
How can I find a replacement since this is a proprietary # and Marantz is no help at all?

Just about any small signal PNP transistor will work there. It dissipates almost no power and has negligible voltage across it. It doesn't even need much gain. Have a look in your spares box and see what you can find. You can even run without it temporarily as it's just part of the current limit.

PS: Just make sure you get the pinout right

[bigdrums925]

CutePDF allows me to print to a file but the file will not open because it is unrecognizable or damaged says the error message
Microsoft Print to PDF is not available on my windows 7.
all I can do is post the .sch file and maybe someone can convert to pdf.
Nope cant do that either- not a valid file type

[nickb]

CutePDF allows me to print to a file but the file will not open because it is unrecognizable or damaged says the error message
Microsoft Print to PDF is not available on my windows 7.
all I can do is post the .sch file and maybe someone can convert to pdf.
Nope cant do that either- not a valid file type

Consult the CUTEpdf online help. In the meantime just zip the sch and post it.

[bigdrums925]

model18schematic.zip

[nickb]

PDF of post #56 M18-7.pdf

I see everything around Q3 is still 0V, Have you removed/replaced it yet?

[bigdrums925]

Yes, there is now -1.3v on collector. 0v on emitter and base.
Waiting for output transistors I ordered

[nickb]

Well ,while you wait you can run it up with a signal generator with no load and see if you now get the full swing on the output using the scope. The driver transistors will provide enough current for small loads.

[bigdrums925]

I get about a 4v P-P swing at the driver collectors
The waveform looks much better but gets fuzzy & distorts as I turn up the tone controls
At least there's progress