Questions raised during composing my parts shopping list for my PIMETA

[applegd]

I am working on the parts shopping list for my PIMETA. Got following questions need help.

Here is the link to see Tangent's PIMETA Parts List: http://www.tangentsoft.net/audio/pimeta/plists.html

(Question 1)
For C1(0.22 µF metalized polypropylene capacitor), on Tangent's optional part list, BC2062 from digikey is listed but I prefer to buy all my parts from mouser in one shot if possible, my question is whether mouser has nicer one for this C1?(I did the search on mouser, but not 100% sure which one to pick)

As this CAP is in the signal path, if it is not good enough, I will just leave it shorted(default).

(Question 2)
For D1(optional crowbar diode, Schottky Rectifier 10 Amp 45 Volt), I plan to buy 511-STPS1045D(made by STMicroelectronics) or 625-MBR1045(made by Vishay). My question is whether it will be better to use 625-MBR1045?

(Question 3)
For CRD(Current-regulating diode), on Tangent's optional parts list, 610-1N5299 from Newark is listed. But I can not find its position on my PIMETA(V1.1C) board. My questions is whether I need to buy it? Is it related to Q1/Q2?

(Question 4)
For DC power jack, Tangent listed two choice: 163-1025(Standard) or 163-4305(close circuit), I want to know which one is better.

(Question 5)
For RCA Input jack, I plan to buy 3501FR(made by Switch Craft). Is this a good choice?

(Question 6)
For C6(10pF NP0 ceramic, 0.1" pitch, radial), 80-C320C100J1G is out of stock at mouser now, is there any alternative I can buy at mouser?

(Question 7)
After reading the POWER SUPPLY section of PIMETA's schematic(http://www.tangentsoft.net/audio/pim...schematic1.pdf, if I use RLED, then the ZNR,FET and RFET are not needed any more, am I right?

Sorry for so many questions, any help is appreciated........

 

[motherone]

I hate to say this, but have you read the parts selection guide from Tangent? He does a great job explaining most of the parts.

1) Mouser will probably have an equivelent metallized polypropylene, probably from Xicon.

2) The crowbar diode is for reverse voltage protection. It's there to save all your chips in case you hook the power supply up backwards. The quality of the part isn't very important.

3) I don't believe there is a spot for a CRD on pimeta boards. Q1/Q2 create the functional equivelent of the CRD.

4) I believe the only different between those is whether or not it has a switch in it.

5) That's a subjective question, and just depends on what you want out of your RCA jacks. You could go with cheap ones, or you could spend $20/each (or more!) for WBT's or Cardas connectors.

6) Try looking at the silver mica 10pf caps. I used those in my pimeta, and all you'll need is some creative lead bending

My other suggestion would be to learn how to read the datasheets for the parts you're selecting. It will make it much easier for you to figure out the answers to your questions on your own.

 

[applegd]

Thanks very much!! motherone

I have read Tangent's parts selection guide before I asked questions, I will read it again.

 

[tangent]

Quote:

Originally Posted by applegd For CRD(Current-regulating diode), on Tangent's optional parts list, 610-1N5299 from Newark is listed. But I can not find its position on my PIMETA(V1.1C) board.

If you mean when using it in place of Q1 and Q2, you simply reuse two of the holes for Q1 and Q2. If you can't see how to do it from the schematic and my op-amp biasing article, don't use a CRD, use JFETs.

If you mean using the CRD for the LED cut-off feature, start reading in the parts selection guide about the zener. That's where most of the application info is.

Quote:

For DC power jack, Tangent listed two choice: 163-1025(Standard) or 163-4305(close circuit), I want to know which one is better.

You don't need a closed-circuit jack, but the physical structure of the jacks are different. Best thing to do is download the catalog so you can see pictures of each. One of them will probably look better to you; choose that one.

Quote:

For C6(10pF NP0 ceramic, 0.1" pitch, radial), 80-C320C100J1G is out of stock at mouser now, is there any alternative I can buy at mouser?

I don't have a part number on hand, but rest assured, this is an absolutely generic part. You just need to do a little searching.

Quote:

if I use RLED, then the ZNR,FET and RFET are not needed any more, am I right?

Yes, it's one set of components, or the other.

 

[applegd]

Thanks very much!! Tangent

I am doing my home work now...

 

[applegd]

One more question.

I want to buy CARDAS RCA jacks, I did a search using google, found hndme.com is selling them. Just wondering anyone used this website before? Any other store websites?

Thanks!

 

[tangent]

Quote:

Originally Posted by applegd hndme.com is selling them. Just wondering anyone used this website before?

Yes, they're legit.

 

[Fitz]

Handmade supplied most of the caps that're in my amp, so yeah, they're fine.

 

[bhjazz]

A lot of people choose to leave C1 out. There is a trace just below it in the board, so you'd have to cut it to install C1. It really depends on what willb e driving the Pimeta. You might want to double check the parts selection guide as it has a link to a discussion regarding input capacitors for headphone amps.

As for Cardas RCAs, Partsconnexion also has them, and even though they are in Canada, they do ship to the US (and I can vouch for their great service).

I'll double check my parts list tonight and try to offer a few more answers.

 

[applegd]

Thanks very much for all the helps!!

I am ordering the parts now.

 

[luvdunhill]

This seemed like a good place to post this question

Can anyone recommend a standoff solution for the PIMETA boards (no standoff holes) and TREAD (with standoff holes)? Are plastic standoffs recommended? Any ideas on what diameter/height would be most appropriate?

Also, any good alternatives from the Molex KK series for input/output/power board disconnects? I'm having trouble finding a good 2x2 square connector that would work in my Digikey catalogue

Thanks all!
-Marc

 

[n_maher]

Generally speaking as long as you have a board-mounted pot you don't need to worry about standoffs.

 

[luvdunhill]

Quote:

Originally Posted by n_maher Generally speaking as long as you have a board-mounted pot you don't need to worry about standoffs.

ah, sorry, I should have mentioned that

I will not be using a board-mounted pot...

Thanks!

 

[soloz2]

I used spare mobo standoffs.... left over from the last few pc builds