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Pioneer SA-9500 : Troubleshooting Noise

Thanks @Skywatcher

I ordered the capacitors. Not going to go further until they get here. No problem.

I have parts ordered for the 61 RCA RC-171F tube amp pictured above as well. Lucked out and got a new Sam's pristine service manual for it. Getting a quote on making new filter caps. I have to make two (maybe all on one) circuit board(s) to replace the Bulplate's/PEC's. Huge learning experience. So basically I have nothing to work on (tech-wise), so going to read some electronics books and watch videos to learn. It's raining all day, so it's good for it.

Thank you.

Rick
 
Hopefully picking this up tomorrow. Much too like social media and I don't usually do that.
 

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Hi

I picked up the Zenith Thursday. It's a Zenith SFD2501R (Chassis 4D20). The outside looks bad, but the inside is in excellent condition. Plays well. When I get ready to work on it I will start a thread in Tubes. I can't find any information on it or the chassis. I think it's 1961-62.
Zenith SFD2501R_Ch_4D20_01_1200.jpg
 
Hi,

Received the capacitors but not sure about one:
Should be UPW1A331MPD 330uF 10v
What I received was FKP2O100331D00KSSD - CAP FILM 33PF 10% 1KVDC RAD
So is it 0.000033 uF 1000v?

I also have a 33UF 50v

What I don't have to match exactly is .22uF 50v & 330uF 10v

I still have trouble with the conversion.

Thanks
Rick
 
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Yup, 33 picofarad.
Maybe this will help with conversion recognition. It still gets to me sometimes too.
1.0 One Farad (massively large capacitance).
0.001 One millifarad, you almost never see 'millifarad' used, more often written as 1000 microfarad (1000µF).
0.000,001 One microfarad, 1µF.
0.000,000,001 One nanofarad (nF), you almost never see 'nanofarad' used, it is usually listed as 0.001µF or 1000 picofarad (pF)
0.000,000,000,001 One picofarad, used to be listed as 1 µµF (micromicrofarad).

EDITED
 
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Thanks @merlynski
So will 33UF 50v work for .22uF 50v & 330uF 10v and
33PF 10% 1KVDC for 330uF 10v
...or do I need to start over. Haha

The parts listed for for AWM-074 were not all in stock so I used the Digi-Key "View Similar" feature. They are not all similar using this, but thought I picked the right ones.

Rick

P.S. I managed to translate old parts for my RS-171F tube amp accurately (had someone at AK in the Tube group verify before I ordered). Maybe beginners luck.
 
Those values are way too far apart to be used as replacements.
Voltage can usually be increased with out a problem, as long as the physical size (and wallet impact) is acceptable. Otherwise, in most cases, capacitance has to be the same, unless there is a good technical reason to change it.
 
Which components are those intended to replace. I will be able to make suggestions by looking at the schematic and component location.
The 330µF cap you listed has a lead spacing of 3.5mm, is that a requirement for fit/location?
 
I was a little distracted when I ordered the capacitors.
AWM-074: C1 & C2: .22uF 10v CSSA: 667-ECQ-V1H224JL2 .22uF 50v Digi-Key Specs for replacement listed here at AK
AWM-074: C3 7 C4: 330uF 6.3v CEA: 647-UPW1A331MPD 330uF 10v Digi-Key Specs for replacement listed here at AK

Where do you find spacing? I have original manual and don't see it. I could "micrometer" it if needed.

Thanks!

EDIT: I just figured out how I messed up - through the option menu. I entered wrong values.
 
I got the lead spacing from the replacement part number (datasheet) you listed. Sometimes it is critical for getting a component to fit in the space on the PCB, other times it is just convenient to drop in correctly. I have a simple divider caliper that I set from the PCB then measure with a dial caliper or ruler.

Those parts look OK to me, though I rarely buy from digikey, unless Mouser is OOS or there is a large price difference. Not that I have a bad opinion of Digikey.
 
Thanks for your guidance @merlynski

I buy from both; well, I haven't bought a lot. Mouser didn't have some parts I needed for a tube amp and their processing took a little longer. The prices were the same. I have no issue buying from either really.

I guess I wait again. Nice being retired. Hardly ever in a rush and plenty to do.
 
You are most welcome. One of the reasons I like Mouser is their warehouse in Texas. Before the WuFlu issues scrambled everything my orders would often be upgraded to overnight shipping (no extra charge) and I would get parts the next day via FedEx.
 
While I am waiting again; I have been looking at various PCB software. I really know very little about designing circuits, but would like to redo some PDF ones I have that are terrible. Just curious as well if there are any that simulate the circuit and give feedback. Just started looking and may have that question answered as I look.
 
I use LTSpiceXVII, though I am still a beginner with it. It is a circuit simulator not a PCB layout program. I have not seen any that do circuit simulation and PCB layout at the same time. It will export the schematic to a graphics format.
 
RICK KING said:
I just figured out how I messed up - through the option menu. I entered wrong values.
Click to expand...

Well, that's only partially true. I have been working on five amps, two tuners and two turntables. Because of this I put all the required parts in a spreadsheet for each component, etc. The bottom line is that I did not format cells and zeros got dropped in some cases or I mistyped. This happen again with another project where .47uF should have been .047uF.

Thankfully the parts are not expensive, but extend my wait. Mistakes are an opportunity to learn.
 
BTW, just dropping a "historical bit"

The SA-9500 was the unit where I proved that there are UKL e-capacitors needed in certain locations to reduce noise the noise floor noticeably AND measurably.
One experimental channel was UPW caps in those locations, and UKL caps (as per the BOM) in the other channel.
 
While waiting I thought I would catch up on some reading. As you can see by the date I'm a little behind. In one of the articles they discuss the inefficiencies in the wire recorder and how the magnetic tape recorder is in development.
AE_May_1947_1200.jpg
 
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