What are these big honkin' resistors I am finding?

[zenpeace69]

I have bought a bunch of resistors to do some projects.  The highest value I have are 2meg.  All of them are the really small 1/4 watt resitors.  I have been looking at other circuits of the pedals I own and I have been finding these big, brown, honkin' resistors.  What is the difference?  Why are they so large?  Why would you use one of these over a small one?  

Also, I have been finding these big honkin' white blocks.  Are these capacitors?  What is the difference between those and the radial or orange drop kinds?

[sir_modulus]

WHATT!!!!! Who made these pedals? are they high voltage (like 300V) or so tube pedals?Those huge brown things are resistors (smaller brown are 1 watt large brown are 2 and 3 watt. The white blocks are 5 - 15 Watt Resistors. That's uterly pointless to put those kinds of things in a pedal that has to deal with (at max) 1V peak to peak.Those Orange Drop caps are for tube amps (usually) and are less than 1 Uf and are rated at around 600V Radial caps are just a different type of electrolytic cap. Radial are often used in Tube amps, for ease of use in wiring or stripboard. Check if there are Transformers on these "pedals" as they might be unfinished or unconnected Tube Amps.

Use small resistors unless your a moron who wants to spend more money to buy useless components.

[cd]

Actually for most circuits, 1/8W resistors would be fine, except they're so small they're too difficult to work with.

Larger resistors (higher wattage rating) have potentially lower noise (see geofex.com) however it doesn't make a whole lot of difference in a guitar pedal.  I'll bet the maker just used whatever they had lying around, I know I do.

[petemoore]

I see these teeny resistors in elec keyboards and computer monitors all the time...they're small, about 1/16'' wide and 1/8'' long in the body...I see 'em all the time, they're too small to read values easily, and so small I like to stick with the larger ones.
 Not that I NEED to know right now,  but what are these, 1/8w?

[sir_modulus]

Are they real small with like a silver body and a black bit with numbers? if so (or kinda like that) then they're Surface mount resistors. They're really teeny resistors for PCB's in industrial use. They can be ruined by even 1/4 watts of power.

[ExpAnonColin]

Often those really big fat ones are used in amps... or used to be used in amps.

Also, back in the day, resistors were just bigger...  now we have tiny tiny SMD resistors, as opposed to what we're used to, the 1/4 watt size.

Here's a nice diagram:


Also, since you mentioned they were brown, they're probably carbon comp rather than carbon film...  Older, higher tolerance.

http://www.w8ji.com/Carbon_Metal_resistors.jpg

-Colin

[Eric H]

 Not that I NEED to know right now,  but what are these, 1/8w?

Pete --you need to know everything right now :mrgreen:

You are correct --1/8 watt. They work fine in stomp circuits. I wouldn't use them inline with the power-supply, or to set current on an LED, though. Personally,  I always check every resistor with a meter before I install it.

-Eric

[zenpeace69]

http://www.w8ji.com/Carbon_Metal_resistors.jpg

-Colin

Yeah, they are the ones at the top left of that picture.  Round fat ones...

So there is no need to use resistors like that?  What if they have an odd value?

I got some odd values when checking them:

8.2
.45
.35   <--- Are these 1k resistors?
34.7

[zenpeace69]

Oh yeah, that rectangular white block has this number on it "1J160M" the "M" has a horizontal line going through it.  What could this thing be?  I assumed it was a cap because it is one of the first components from the "in".

[ExpAnonColin]

You actually are probably going to want odd values less, I much prefer  having a large stock of 1, 22, and 47's than a bunch of odd values...  Not a whole lot of use for them, but you can always putt  hem in a pedal and say it has VINTAGE NOS parts in it...

-Colin

[sir_modulus]

That would definatley make an interesting pedal. Better and not as crappy as some stuff i've seen on Ebay