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The old list has many obsolete parts that are no longer available so I would like to update it.

Is there any reason I cant or shouldn't use any of these parts to recap 2465A and 2465B scopes? I do have one or two caps that are only rated to 85C, do I need to upgrade them to 105C? The old list changed some resistors labeled as FILM to Ceramic, I changed them to Metal Film due to price and availability.

Once I get the list right I will update it with quantities and upload it for others.

___________CAPACITORS____________

C1021 & C1022
Electrolytic Capacitor, 330 ?F, 200 V, ED Series, ± 20%, Radial Leaded, 18 mm Manufacturer: PANASONIC ELECTRONIC COMPONENTS EEU-ED2D331


C1016 & C1018
Safety Capacitor, 0.068 ?F, X2, R46 125°C, 275 V, PP (Polypropylene) Manufacturer: KEMET R46KF268040H1M


C1025, C1260, C1280, C1300, C1330, C1350, C1101, C1102
Electrolytic Capacitor, Miniature, 100 ?F, 50 V, PW Series, ± 20%, Radial Leaded, 8 mm Manufacturer: NICHICON UPW1H101MPD1TD


C1034
Tantalum Capacitor, 4.7 ?F, 35 V, T350 Series, ± 10%, Radial Leaded, 2.54 mm Manufacturer: KEMET T350E475K035AS


C1020 & C1051
Safety Capacitor, 2200 pF, Y2, B32021 Series, 300 V, PP (Polypropylene) Manufacturer: EPCOS B32021A3222M000


C1052
Safety Capacitor, 0.01 ?F, X2, B32921 Series, 305 V, PP (Polypropylene) Manufacturer: EPCOS B32921C3103M000


C1066
Electrolytic Capacitor, 4.7 ?F, 50 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1H4R7MDD1TD


C1065
DC Film Capacitor, 0.056 ?F, 400 V, PET (Polyester), ± 10%, ECQE(F) Series Manufacturer: PANASONIC ELECTRONIC COMPONENTS ECQ-E4563KF


C1072
Electrolytic Capacitor, Miniature, 3.3 ?F, 400 V, PK Series, ± 20%, Radial Leaded, 8 mm Manufacturer: RUBYCON 400PX3.3MEFC8X11.5


C1110, C1111, C1113, C1114, C1115, C1116
Electrolytic Capacitor, 330 ?F, 50 V, EB Series, ± 20%, Radial Leaded, 10 mm Manufacturer: PANASONIC ELECTRONIC COMPONENTS EEU-EB1H331


C1120, C1130, C1132, C1220, C1240
Electrolytic Capacitor, Miniature, 10 ?F, 250 V, VR Series, ± 20%, Radial Leaded, 10 mm Manufacturer: NICHICON UVR2E100MPD1TD


C1400 & C1402
Electrolytic Capacitor, 47 ?F, 35 V, KA Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UKA1V470MDD1TD


C1274 & C1291
Electrolytic Capacitor, Bi-Polar, 1 ?F, 50 V, VP Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UVP1H010MDD1TD


A1 board recap - 2465A
Electrolytic Capacitor, 10 ?F, 50 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1H100MDD1TD


A1 board recap - 2465A
Electrolytic Capacitor, 22 ?F, 35 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1V220MDD1TD


A1 board recap - 2465A
Electrolytic Capacitor, Miniature, 220 ?F, 35 V, HE Series, ± 20%, Radial Leaded, 10 mm Manufacturer: NICHICON UHE1V221MPD6TD


A1 board recap - 2465B Ser >50k
EEE-FC1V100R - SMD Aluminum Electrolytic Capacitor, Radial Can - SMD, 10 ?F, 35 V, FC Series, 2000 hours @ 85°C


A1 board recap - 2465B Ser >50k
PANASONIC ELECTRONIC COMPONENTS - SMD Aluminum Electrolytic Capacitor, Radial Can - SMD, 33 ?F, 10 V, FC Series, 2000 hours @ 85°C


___________RESISTORS____________

R1010 & R1019
Through Hole Resistor, 15 ohm, PR02 Series, 2 W, ± 5%, Axial Leaded, 500 V Manufacturer: VISHAY PR02000201509JR500


R1020
Through Hole Resistor, 270 kohm, PR03 Series, 3 W, ± 5%, Axial Leaded, 750 V Manufacturer: VISHAY PR03000202703JAC00


Thank you
Timothy

That would be great.

I did that back in 2013 I think. Mostly Newark.com parts.

2465A and 2465 still going strong.

Ancel

This last March I did it for a 2465B I am working on.? So I uploaded my list to the files section for your reference.? It includes part numbers for three resistors in the LVPS that often need to be replaced.

Thanks for that effort, but I'm not going to agree with some of your choices.

I have sold hundreds of these kits to 24xx owners all over the world, and have paid close attention to the comments of my users, who were not shy in recommending improvements over the years.

1.I see that you've increased the VOLTAGE rating of some capacitors. It's not a smart idea to increase the VOLTAGE rating value of a given capacitor, without checking the ACTUAL voltage passing through the capacitor.
Wherever practical, the VOLTAGE rating of a capacitor should NEVER be more than about 1/3 more than the actual voltage passing though it, as the capacitor will not be NOT energized correctly, leading to efficiency losses. 10uF/50V is not a smart choice, where 10uf/25V is. Same for 10uF/250V replacing a 10uF/160V. The same goes for all the units where the OP increased the voltage rating (in this posting's list), without checking the circuit requirements.
2. It was already agreed that Panasonic EB (although a highly reliable capacitor), is NOT optimal for THIS switching power supply. The MOST suitable capacitor series for these units is NIchicon HE and PW, due to their much higher Ripple capabilities, and these series are freely available at Mouser and Digikey, The Nichicon PM is not my go-to choice, when I want a repair with the absolute longest reliability, and nor are Rubycon caps at all (but that's only my opinion).
3. Selecting a Nichicon KA capacitor is unacceptable. This is an Audio-Grade cap, which has absolutely no place in a SMPS.
4. For the BiPolars and Tantalums, I ALWAYS recommend Wima MKS2 films - compact, precision, and FAR more reliable. I do NOT use Tantalum caps at all.
5. ALL the required Film capacitors are available from Vishay - MKP3381 X1 series, MKP3366 Y2 series, MKT372 DC.
6. ALL the caps here should be rated for 105C. There is no reason whatsoever to install a 85C cap here.
7. The Resistors - Vishay PR03 - Power film series

In short, the optimum components are STILL available from Mouser and Digikey, even if Newark doesn't have them.

My point is - if an owner is going to do the job (and doesn't want to redo his work in a few years), then do it right the first time. There is a world of choices out there, and NOT all of them are the smartest choice for THIS application.

Menahem Yachad
CondorAudio
Jerusalem Israel

Menahem,

Thank you for taking the time to write that reply. I am a novice circuit designer and I am just beginning to learn the importance of things like ESR in a circuit and your post is the guidance I was looking for. The myriad of capacitor series are mind numbing. I was trying to revise the list found it 2465LVPS_ReCap, A1 recap-parts.xls I found in the files section. Almost all of the parts were upgraded with higher voltage parts and from my research many people were recommending upgrading the voltage with replacement parts with just a few voices of warning about higher voltage caps never fully energizing.

I will take more time searching for suitable Nichicon HE and PW replacements. There were times I chose a part just based on a lower price point and I see now that would be a mistake. I will skip the tantalums and I will select film caps and resistors from Vishay as you recommend and make sure they are all 105C rated.

I stuck with one source to try and save on shipping costs but I see that I may have to source parts from more than one distributor.

On Sat, Jun 9, 2018 at 04:45 pm, machineguy59 wrote:

This last March I did it for a 2465B I am working on.? So I uploaded my list
to the files section for your reference.? It includes part numbers for three
resistors in the LVPS that often need to be replaced.

Ancel, I searched the files section from March and I cannot find anything related to the 2465B caps. Can you send me the link or point me in the right direction.

Thank you

Timothy, What's with the multiple copies of your messages - it's tedious seeing seven copies of the same post!

Do remember that most of us receive the posts by email so if you make a post using the web UI and then change it six times, everyone will receive seven messages saying pretty much the same thing :(

Dave

I believe you are asking for this:
/g/TekScopes/files/Caps%20list%20updated%20March%202018.xlsx
I did not verify the series information but all are high temp, long life and most are either Nichicon HE, PW, or Panasonic EB.? I also list the ceramic and tantalum capacitors but I don't replace those.? My logic is they seldom fail once they are "mature".

I have been switching to aluminum poly caps which cost more but it
their specs look so much better. Lower ESR, Longer life, Higher temp.
handling.

On Sat, Jun 9, 2018 at 8:14 AM, mustang_gt_y2k via Groups.Io
<mustang_gt_y2k@...> wrote:

Is there any reason I cant or shouldn't use any of these parts to recap 2465A and 2465B scopes? The old list has many obsolete parts that are no longer available. I do have one or two caps that are only rated to 85C, do I need to upgrade them? Once I get the list right I will update it with quantities and upload it for others.

Electrolytic Capacitor, 330 ?F, 200 V, ED Series, ± 20%, Radial Leaded, 18 mm Manufacturer: PANASONIC ELECTRONIC COMPONENTS EEU-ED2D331

Safety Capacitor, 0.068 ?F, X2, R46 125°C, 275 V, PP (Polypropylene) Manufacturer: KEMET R46KF268040H1M

Electrolytic Capacitor, Miniature, 100 ?F, 50 V, PW Series, ± 20%, Radial Leaded, 8 mm Manufacturer: NICHICON UPW1H101MPD1TD

Tantalum Capacitor, 4.7 ?F, 35 V, T350 Series, ± 10%, Radial Leaded, 2.54 mm Manufacturer: KEMET T350E475K035AS

Safety Capacitor, 2200 pF, Y2, B32021 Series, 300 V, PP (Polypropylene) Manufacturer: EPCOS B32021A3222M000

Safety Capacitor, 0.01 ?F, X2, B32921 Series, 305 V, PP (Polypropylene) Manufacturer: EPCOS B32921C3103M000

Electrolytic Capacitor, 4.7 ?F, 50 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1H4R7MDD1TD

DC Film Capacitor, 0.056 ?F, 400 V, PET (Polyester), ± 10%, ECQE(F) Series Manufacturer: PANASONIC ELECTRONIC COMPONENTS ECQ-E4563KF

Electrolytic Capacitor, Miniature, 3.3 ?F, 400 V, PK Series, ± 20%, Radial Leaded, 8 mm Manufacturer: RUBYCON 400PX3.3MEFC8X11.5

Electrolytic Capacitor, 330 ?F, 50 V, EB Series, ± 20%, Radial Leaded, 10 mm Manufacturer: PANASONIC ELECTRONIC COMPONENTS EEU-EB1H331

Electrolytic Capacitor, Miniature, 10 ?F, 250 V, VR Series, ± 20%, Radial Leaded, 10 mm Manufacturer: NICHICON UVR2E100MPD1TD

Electrolytic Capacitor, 10 ?F, 200 V, VY Series, ± 20%, Radial Leaded, 8 mm Manufacturer: NICHICON UVY2D100MPD1TD

Electrolytic Capacitor, 47 ?F, 35 V, KA Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UKA1V470MDD1TD

Electrolytic Capacitor, Bi-Polar, 1 ?F, 50 V, VP Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UVP1H010MDD1TD

Electrolytic Capacitor, 10 ?F, 50 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1H100MDD1TD

Electrolytic Capacitor, 22 ?F, 35 V, PM Series, ± 20%, Radial Leaded, 5 mm Manufacturer: NICHICON UPM1V220MDD1TD

Electrolytic Capacitor, Miniature, 220 ?F, 35 V, HE Series, ± 20%, Radial Leaded, 10 mm Manufacturer: NICHICON UHE1V221MPD6TD

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On Sun, Jun 10, 2018 at 01:18 am, David C. Partridge wrote:

Timothy, What's with the multiple copies of your messages - it's tedious
seeing seven copies of the same post!

I am sorry, I was not aware that editing a message caused this. I will refrain from doing so in the future.

On Sun, Jun 10, 2018 at 09:57 am, machineguy59 wrote:

I believe you are asking for this:
/g/TekScopes/files/Caps%20list%20updated%20March%202018.xlsx

Thank you, You deserve a medal!

Im happy to help.? Posting it caused me to verify several points in my list.? Let me know if you find more.? The most glaring problem I found was substituting some Nichicon for Panasonic and not changing the "Type" column.

Its mostly correct, but I found an error, maybe two.

C1065 .056 ?F 250 MTLZD .056 ?F 300 Vishay Polyester Film 399-7635-ND
The lead spacing is to wide for the replacement part. Should be 7.62mm but the part is 14.50mm. I could not find a part that fits from Kemet or Vishay @ Digi-key.

C1050 0.22 ?F 400 PLSTC 0.22 400 Kemet Polyester 495-4473-ND
The lead spacing is not far enough, are you adding tinned copper wire to lengthen the lead or is this a mistake?

C1130 10 ?F 100 ELCTLT 10 ?F 160 Nichicon PW 493-11888-3-ND
Link bring up minimum quantity of 500, I think you can use this link instead ?
FYI I ordered these and they sent the wrong part. I will find out sometime tomorrow if they have corrected the issue and post an update.

For C1120 10 ?F 100 ELCTLT --> 10 ?F 160 ,
Can I use or is there some benefit to using a 160V cap?

C1132 10 ?F 160 ELCTLT 10 ?F 160 Nichicon PW
I pulled out a 250uf 20v from this location

C1115 250 ?F 20 ELCTLT 330 ?F 50 Panasonic EB
I pulled out a 10uf 160v from this location

I seem to remember reading this is also an error in the documentation.
Also can I use a 20v 330uf cap for C1132 or is the 50V better? I'm just remembering what Menahem said about larger caps...

Sorry for multiple posts for all of you on the mailing list. Groups.io really should filter out edits...

I only have a short minute but want to post this.? I will comment more on your other posts later when I have more time.
All Tektronix documentation has the physical locations of C1115 and C1132 interchanged.? You may want to update your documentation of PCB layout to show these two capacitors interchanged.? The power supply will not work if you install new capacitors based on the Tektronix documentation for these two parts.? You can verify the proper positions with your ohm meter.? C1115 positive terminal must connect to L1115.

Thank you for posting your findings.? Here is a complete answer with rationale for some of my choices.? Hope this helps.

You wrote:>

C1065??? .056 ?F???250??? MTLZD??? ??? .056?F??? 300??? Vishay Polyester?Film??? 399-7635-ND?
The lead spacing is to wide for the replacementpart.? Should be 7.62mm but the part is 14.50mm. I could not find a partthat fits from Kemet or Vishay @ Digi-key.

You are right.? I am sorry I still have that information inthe list.? I gave up trying to fit thatlarge cap and accepted one from Panasonic:?P12080-ND I think it’s a decentchoice but not perfect.

You wrote:>

C1050??? 0.22 ?F???400??? PLSTC??? ???0.22??? 400??? Kemet Polyester???495-4473-ND
The lead spacing is not far enough, are you addingtinned copper wire to lengthen the lead or is this a mistake?

That is a dilemma.? The original fitment is an axial capacitorwith the leads spaced about 33 mm.? Icould find one from Illinois Capacitors 1572-1684-ND ?with a body that is 29 mmlong. ??It costs 1.14 USD and will workwell.? There is also one from Vishay BC2609-NDThat is 31 mm long for 3.48 USD.?I chose to add leads to a radial cap by TDK 495-4473-ND This only cost 0.82 USD but it was not a good choice.? My next recap will be either the Illinois Capacitor or the Vishay.? They might be abit long but there is ample room to raise them from the board and bend theleads back to fit the holes. ?

You wrote>

C1130??? 10 ?F???100??? ELCTLT??? ??? 10?F??? 160??? Nichicon PW???493-11888-3-ND
Link bring up minimum quantity of 500, I think youcan use this link instead? ?
FYI I ordered these and they sent the wrong part.I will find out sometime tomorrow if they have corrected the issue and post anupdate.

Sorry for the confusion.? Digikey corrected my order (from 493-11888-3-ND to 493-11888-1-ND) but I did notcorrect the list.? I meant instead 493-11888-1-ND which is the same cap in small quantities.? I prefer it over your suggestion because ithas a much higher life rating (5000 hours) but only costs 0.08 USD more. ?

You wrote>

For C1120??? 10 ?F???100??? ELCTLT??? ? -->???? 10 ?F??? 160? ,
Can I use is there some benefit to using a 160V cap??

The choice of 160 Volt caps was done years ago bysomeone who made the original list.? Ionly updated it to get longer life.? Multiplemembers of the forum have used 160 Volt substitutes with no reports ofproblems.? I have not looked for 100 voltparts with long life ratings.? But Iprefer my suggestion over the ones you linked to because of the lifetimeratings.

You wrote>

C1132??? 10 ?F???160??? ELCTLT??? ??? 10 ?F???160??? Nichicon PW
I pulled out a 250uf 20v from this location

C1115??? 250?F??? 20??? ELCTLT?????? 330 ?F??? 50??? Panasonic EB
I pulled out a 10uf 160v from this location

I seem to remember reading this is also an error in thedocumentation.

Actually, Tektronix documentation is incorrecthere.? You pulled a 20 volt cap from thelocation MARKED C1132 and a 160 volt cap from a location MARKED C1115.? The markings are interchanged by Tek on everydocument I find for these power supplies.??Take care when putting things back.?Use your Ohm Meter to check that C1115 is connected to L1115.

You wrote>

Also can I use a 20v 10uf cap for C1115 or is the 50V better?I'm just remembering what Menahem said about larger caps... I'm justremembering what Menahem said about larger caps...

The 50 Volt capacitor had a better lifeexpectancy.? Menachem has a good pointabout ESR of higher voltage caps.? But Ithink you will find that in these lower voltages there is little difference inESR between 20 volts and 50 volts.? So Ichose for other reasons.? Sometimes justto make a bulk order of one part number, sometimes because it looked moreuniform on the completed board.? Butalways for higher life and higher capacitance.?(Take note, higher capacitance is not always a good thing so check theapplication before deviating from spec.)

Let's get some clarity on this.

A decoupling cap can USUALLY have the CAPACITANCE increased, but NOT the voltage rating.
Sometimes the cap's VOLTAGE rating should even be decreased, according to the actual circuit voltage.
I hope that's clear!

On these 180uf/40V, the optimum substitute IN THIS CIRCUIT is a 330uF or 470uF/50V, preferably Nichicon PW or HE, but DEFINITELY NOT Panasonic EB. That "updated" list is completely misleading, by listing Panasonic EB caps as "suitable".

On the 10uF/100V caps, with about 80VDC going through them, you do NOT install a 10uF/160V to save money, by buying 10/160's for both the 10/100 and 10/160. You put the correct-rated cap in the correct place.

C1115 and 1132 are WRONG in the manual.
What you pulled out, is EXACTLY what you reinstall.
The 250uF/20V caps are replaced with 330uF or 470uF/25V. PW or HE. Nothing else.

The Film caps as follows - all VISHAY, and ALL confirmed available from Mouser.
I do NOT know about Digikey.
2.2nF BFC233660222 Qty 2
10nF BFC233660103 Qty 1
56nF BFC237241563 Qty 1
68nF BFC233810683 Qty 2

These all have the correct lead pitch, and all fit PERFECTLY, both physically and electrically.

And a last word of caution - if you're looking at other brands/models to save a few cents, then DON'T!
The headaches are NOT worth it.
"Only a rich man can afford to buy cheap"

If somebody would like to take it upon himself to update the "updated 2018" cap list onsite here with regard to these salient points, it would save a lot of newbies and hobbyists headaches, as they trust the knowledge of the men who put this list together, and there should NOT be any errors in that list.

Best of luck!

Menahem Yachad
Jerusalem Israel

But, alas, what you say is not true. It once was, back when
electrolytic capacitors used rather caustic electrolytes that
ate away the aluminum oxide dielectric layer, but that hasn't
been the case for about 30 years.

It is just fine to raise the voltage rating of an electrolytic
capacitor used as a decoupling cap, filter, bypass, whatever.

It is also just fine to buy only 10uf 160V caps, and use them
to replace both the 10uf 100V caps, and the 10uf 160V cap in
the 2465's power supply.

Just like it was fine when you specified 330uf 50V caps to
replace both the 250uf 20V and the 180uf 40V caps in the
power supply.

This isn't audio gear where you have to worry about how the
end user might "feel" about your choice. You can use valid
technical reasons.

If you need some evidence to back my assertions, grab any old
bag of electrolytic capacitors that have been sitting on the
shelf for years, and measure the capacitance. They will all
measure at the nominal value... after years of being operated
at the extremely low voltage of 0V. I have just such a bag
of nichicons from a project where I overbought the caps. This
was back in the 1970's. They all still read 2200uf +/- 10%.

-Chuck Harris

M Yachad wrote:

Chuck

“If you need some evidence to back my assertions, grab any old bag of electrolytic capacitors that have been sitting on the shelf for years, and measure the capacitance. They will all measure at the nominal value... after years of being operated at the extremely low voltage of 0V. “

Not sure if you’re trying to be funny, or if you’re serious.

If you’re serious, I think your comparison is irrelevant. Unless a capacitor is in a working environment, coping with heating and cooling cycles, you cannot compare it to a shelf model, no matter what voltage. And statistically, throwing a single bag of old undocumented caps into the ring here, is irrelevant.

“I have just such a bag of nichicons from a project where I overbought the caps. This was back in the 1970's. They all still read 2200uf +/- 10%.”

In the best case, it just goes to prove that Nichicon is still the right choice, today.

“But, alas, what you say is not true. It once was, back when electrolytic capacitors used rather caustic electrolytes that ate away the aluminum oxide dielectric layer, but that hasn't been the case for about 30 years.”

On the contrary, the low-ESR capacitors of today DO contain corrosive electrolyte.
Do I need to expound on the A5’s damage?

Read up on Chemicon’s recent hard lessons on their KYx KZx and LXx series, with the problems, and subsequent requirement to reformulate the highly corrosive electrolyte.

We only get to know about these problems, LONG AFTER the caps have been installed in the customer’s machine, and he has paid for them.
So why not anticipate the problem, and plan for it?

Therefore, there is enough empirical evidence to support the postulation that the issue STILL exists today.
And I simply do NOT see this as a problem.
We can choose to ignore it, or we can choose to plan our BoM, with the knowledge that a poor choice may bite us in the future.
My way to deal with this exact issue, is to suit the capacitor voltage rating to the actual circuit voltage.
Is that such a difficult decision to make?
To me, it’s simply preempting the possible problems which corrosive electrolytes cause.

It’s a free world.
I choose the path of caution and reliability – I have customers to answer to, and my hard-won reputation to uphold.

A man who’s rebuilding his own scope can throw whatever he wants in there – the only one he needs to answer to, is himself. And in that case, to him, this discussion is irrelevant.

“Just like it was fine when you specified 330uf 50V caps to replace both the 250uf 20V and the 180uf 40V caps in the power supply.”

You’re right – in my PDF, I did say that. I did not pay sufficient attention during my proofreading to differentiate. However, after that PDF was published, there was a lot of positive feedback on this forum, pointing out the errors and suggesting the changes which should be made. All of those changes are included in my ebay repair kit, which has sold nearly 200 units, the vast majority of them not on ebay.

“This isn't audio gear where you have to worry about how the end user might "feel" about your choice. You can use valid technical reasons.”

I’ve been around much too long to give much thrift to what people “feel” about my conservative way of life, much less to audiophools who chase after every new bottle of snake oil. My principle is “First reliability, then sound”. Why? If the machine doesn’t work, then what worth are all the salesman’s promises on the superior sound which it is supposed to it deliver?

G-d bless you all for your input – it’s what keeps this forum alive and each of us learning more as we go along.

Menahem