PLUTO-2 parts ordering at Digikey

[BrianL]

your first plan sounds good. With the short leads on the cap, you don't want to risk damaging the area where the leads go into the epoxy by twisting and screwing (no matter how careful you are) on the leads. Better to hook/twist your jumper around the existing lead and then solder.

[David Miller]

Pick up one cap, extend one tail, solder the cap to a board.
If that works, do likewise to the cap that fits in the compliment place on the second board.
Pick up another cap…
That would be my method.
Dave

[nezbleu]

I had ordered a couple of Vishay BC Components polypropylene box caps from Newark for some values that Digikey didn't have, and they have a really small and square footprint with short leads. I soldered a heavy-ish lead clipping in one hole and bent it over so it was essentially lying on the circuit board, and bent one lead of the capacitor so it was also parallel to the board. Then I inserted the other lead of the cap into the other hole such that the bent lead was resting on the soldered clipping, soldered it in place, and then soldered the two "horizontal" leads together. Maybe I will post a picture.

I had also ordered a couple of Vishay Roederstein 1% polypropylene box caps -- they are also small and square, but have nice long leads. I also ordered some LCR Components polystyrene caps (also 1%) which are axial and have long leads, so they are easy to fit (especially for the "flying" caps in the 2.1 mod). Unfortunately, most of them were back-ordered including 20 33nF caps. So it will be a few more weeks before I can power up my circuit boards. When Newark say they are in stock but "Supplier stock" it means they are not in stock.

[roehrig]

Nezbleu,

JimB posted an elegant solution to the "33 nF problem" a while back, here:

http://orion.quicksytes.com/viewtopic.php?f=12&t=1018&start=105

I'm sure that the idea would also work for many of the other capacitor woes ailing us these days. In Jim's solution, he changes the 33 nF capacitor to a 30 nF part, of the same high quality, and of which there are plenty in stock at DigiKey. Then, he "re-scaled" the circuit that used this capacitor, by changing resistor values appropriately, and the result is a circuit essentially equivalent, but using readily available parts. The point is that 1% resistors are commonly available, but the fancy 1% or 2% poly caps are becoming less so.

One way to see how this works is to study SL's spreadsheet pz-eql.xls (see the Pluto+ page, in the "Frequency response equalization section"). The magic number is the value of "k". Changing this changes the impedance scaling of the filter stage. Small changes in k result in identical circuit performance, but different values of the resistors and capacitors. Jim did the same thing with some of the Pluto circuit (specifically, the 1000 Hz crossover section). He changed a capacitor value, and then brought everything back into focus by changing the associated resistors.

Steve

[earyan]

New user here—I've been lurking for a while, and when the solder-tab Aura tweeters came back into stock at Madisound I took the plunge.

Now I'm trying to order the electronic components from Digi-Key. I have registered with Digi-Key, but when I click on the link in the first message in this thread I get a 'Page not found' from Digi-Key in twelve different languages. Am I doing something wrong?

Thanks for the help.

Also new to the group. I had same problems you had. This is probably too late to help you but other newbies might use it. If you have excel you can make up two columns from Linkwitz's parts list (copy and paste) quantity and part number. Then use Digikey's import text for a BOM (again copy and paste). Apparently when Digikey changed their catalog the old list would no longer work. This worked for me (split list into 3 parts).

[James]

Hi all. Not sure if this thread is still active, so I'll post a new thread as well. I'm in the 'ordering" stage of building the cross-overs for the Orion+ and I'm having the same problems finding the right capacitors. I've managed to make substitutions for all of the caps except the 33nF 2% (orion uses P3919) and the 330 nf 2% (P3931). The only replacements Digi has that have the same dimentions are all 5% (with the exception of BC2079-nd which has much shorter leads).

In searching the WEB I found Electronic Concepts (http://www.polycarbonatecapacitors.com/). They are on vacation right now, so no one is answering the phone. According to the website they specialize in polycarbonate capacitors in our ranges and tolerances. I don't know the prices yet. Has anyone heard of this company or know whether polycarbonate would be ok in our applications?

Jim

[wizardofoz]

Ok...I havent had my cuppa today yet....but... how does one get the BOM for the 2.1 or even the 2 to load in digikey site. I chatted with online support and the link in the first post of this thread is no good nor could he find any pluto BOM project. Do I have make one from scratch? What are those recent posters using to get the bulk of the order input?

Some help here would be really shweet if anyone has a moment .... my board drivers and pipes are all in transit and now I need the little bits to piece it all together.

Paul

[stefan]

Hi
A recent BOM would be extremely helpful for me as well.
I have no idea otherwise to get these capacitors (or most of them at least)

Paul, did you get one from someone, did you do your own?

Stefan

[wizardofoz]

I haven't got anything yet but the caps seem to be the hardest for accurate tollerances, the rest I can get locally in Singapore diy shops, and at much better prices than digikey or mouser

[lamikeith]

I placed my big order with Digi-key today. As time moves on, more parts specified on the spreadsheet become obsolete. Even the suggested replacement Panasonic ECH-S line of PPS film capacitors has been discontinued. Below is how I handled the nine parts that are no longer available from Digi-key, and the one part that is on back-order for the next six months. My goal was to find parts that matched as closely as possible to the original and could be obtained from Digi-key. Naturally, there were some compromises (5% over 2%, 10mm lead spacing over 15mm). I am not an electrical engineer, only a humble electronics technician in a former life, so please feel free to correct any obvious mistakes that I may have made in choosing substitute parts.

Part Spec Original # Replacement # Notes

-15VDC Reg. 500ma TO-220 LM79M15CT-ND LM7915CT/NOPB Nat'l Semi -15VDC 1.5A TO-220

820pF P 5% 50V 5mm P3900-ND PS1821J-ND Pana ECH-S PPS 5% 100V 5mm

2.2nF PP 2% 50V 5mm P3222-ND PS1222J-ND Pana ECH-S PPS 5% 100V 5mm

10nF PP 2% 50V 7.5mm P3103-ND PS1103J-ND Pana ECH-S PPS 5% 100V 7.5mm

33nF PP 2% 50V 7.5mm P3333-ND PS1H333J-ND Pana ECH-S PPS 5% 50V 7.5mm

100nF PP 2% 50V 7.5mm P3104-ND PS1104J-ND Pana ECH-S PPS 5% 100V 12.5mm

330nF PP 2% 50V 17.5mm P3334-ND PS1H334J-ND Pana ECH-S PPS 5% 100V 15mm

470nF PP 2% 50V 17.5mm P3474-ND PS1474J-ND Pana ECH-S PPS 5% 100V 15mm

0.1uF MP 10% 450VDC 15mm P10755-ND EF4104-ND Pana ECQ-E MP 10% 400VDC 10mm

22000uF E 50V 10mm P6946-ND 338-1599-ND CDE E 50V 10mm

Key
P = Polyester
MP = Metallized polyester
PP = Polypropylene
PPS = Polyphenylene Sulphide
E = Electrolytic

[lamikeith]

*sigh*
So much for my nicely-formatted table. I have attached what I hope is a legible text file.

[PaulWooferwitz]

It comes out jumbled in Windows Notepad (my default text app) but comes through beautifully formatted in Wordpad.

Thanks, Keith, that might come in handy one of these months.

[wizardofoz]

I'd did up a boom in digikey and pluto search should find it, I'll post the boom number later when I can get on my Mac. I will also update with the above alternate parts and name it accordingly, and even order it just for fun...see if my Singapore electronics shop can beat the digikey boom and then compare the sounds and test points of the 2 different builds.

[wizardofoz]

Sorry that should be BOM not boom ... My iPad likes to overcorrect with loud words

[lamikeith]

Today I received the following from Digikey:

"Due to an inventory discrepancy we do not have any of part number P3893-ND available to ship. As this part is now obsolete, I'm sorry but we are unable to backorder it for you, so this item has been removed from your order."

P3893-ND is 220pF located at C 2, 4, 21, 27, 63, 68. Digikey has nothing close that I can see. Newark has LCR, Wima, and Vishay parts that may suit the purpose. Comments welcome.