[andrzejpw]

I'm looking for a few values of visay/dale resistors at mouser. I just can't find them!

470
4.7
22K
220K
47

Anyone know where I can find these?

Vishay/Dales: 71-RN55D-F-$$$

where $$$ is replaced by the value.

 

[puppyslugg]

Try:

475
4.75
22.1K
221K
47.5

 

[andrzejpw]

Hmm, thanks. Is 4.75K ok instead of 4.7? I'm guessing yes. . .

Oh, and I still can't find 470

 

[andrzejpw]

wait, I found 475. That's ok, right?

That'll give me a gain of 5.71 . . .

 

[Nezer]

Quote:

Originally posted by andrzejpw Hmm, thanks. Is 4.75K ok instead of 4.7? I'm guessing yes. . . Oh, and I still can't find 470

This isn't an exact science, just get close.

Download the passive section of Mouser's catalog and they have a table on the page with the Visahy CMFs that list all the available values.

 

[JMT]

Quote:

Is 4.75K ok instead of 4.7?

A 1% variation is perfectly fine. Keep in mind that your resistors will have a 1% tolerance so the values of the resistors will not be exact. It will be important to use a digital multimeter to match the resistors between channels. Buy a few extra than you need so you can match.

 

[tangent]

Quote:

Download the passive section of Mouser's catalog and they have a table on the page with the Visahy CMFs that list all the available values.

There are several such tables throughout the section, because these values are standardized. Every manufacturer that makes 1% resistors makes a 4.75K version, because 475N (N being a power of 10) is a standard E-96 resistor value. That's why you can also find 475 ohms for R3 and 47.5 for R7-R9.

No, I'm not going to change my schematic to use 1% resistor values -- inertia has captured me.

(47N is a 5% resistor value; there are only 24 standard 5% values for each power of 10, so they're a lot easier to memorize, and so are more common when engineers are designing extemporaneously.)