Spare Parts resistors and caps

[docbob52]

Does anyone know the brand of metal film resistors, ceramic and electrolytic caps that Doc uses in his products.  I need to get an assortment of especially the metal film resistors since my Radio Shack closed here.  All advice appreciated.

[aragorn723]

The resistors are Vishay-dale RN55D's. 

Dave

[Chris65]

The brands would vary somewhat I would guess, depending on what's available, price from the supplier, etc
And also vary with each particular kit.

As you mention RadioShack, I guess you're in the States, there you have good access to suppliers such as Mouser, Digikey & others.
Unless you particularly want boutique parts, hard to go wrong with known brand names like Vishay, Panasonic, Nichicon & many others.

[mcandmar]

I pretty much stick to Vishay Dale resistors for no particular reason, even though they are more expensive than regular metal films. 99% of the parts you will ever need can be sourced from Mouser.

[Paul Birkeland]

It's easy enough to get a bulk assortment of metal film resistors on eBay for $50-75 or so.  1/4W parts will work well for attenuators and some functions in high voltage circuits, though not all of them.  You may find it more helpful to buy an assortment of Vishay PR-01, PR-02, and PR-03 resistors for that duty.

We do not use one brand or one type of resistor, as a given position in a circuit may call for something specific.  We do not ascribe to the philosophy that every resistor in a kit needs to be the same to "voice" it properly. 

For electrolytic capacitors, having 22uF, 47uF, 100uF, and 220uF at 450V and 250V would be a decent set of spare parts.  Look for high lifetime and high allowable ripple current. 

[Doc B.]

I don't understand what these parts are for. A needed repair? Spares for a working piece of equipment? A pile of parts to experiment with?

I would just save my money and order exactly what I needed for a repair. For spares I would also wait. The only things electrical that will wear out are the tubes and the electrolytics. The caps will take like 10 years to deteriorate. So why buy caps now that will sit for ten years and deteriorate on the shelf before you even use them?

As far as resistors, if you want spares for a kit just get as close as you can to what we used. If you just want a pile for experimenting, the first rule is that you will never have the value you need and you will need to order it anyway. So just start buying them as you need them. In a few years you will have a massive supply of unused resistors in all sorts of values. But if you really want a box full of resistors sitting on the shelf from the get-go I would suggest buying a few of each of values that are orders of magnitude apart, like 10 ohms, 100 ohms, 1000 ohms, 10K ohms, 100K ohms, 1M, etc. You can series and parallel those values to make other values you might want to experiment with, then order the proper value once you find out what it needs to be. Probably stay with 1/4W and just accept that occasionally you will need to order higher power rated values.

[Chris65]

As far as resistors,............ the first rule is that you will never have the value you need and you will need to order it anyway.

So true!!

[mcandmar]

That is so true, and if you have the right value, it will be the wrong wattage.

You can buy a big bag of E24 value .5w metal films from eBay for very little, i use those for mockups and testing.   For everything else i have a big box of recycled components, from working in IT i regularly have to dispose of elecy equipment so i keep any boards with useful components.  Old TV's and laser printers are a great source for film and electrolytic caps, and high wattage resistors.

[ALL212]

If I order components I always order 2 to 3 times as many as I need at the moment.  I've got a pretty good stash from doing this.  The cost is usually minimal to add another 1/2 dozen.  It also allows you to match values if needed.