Noob capacitor question

[wavley]

LOL     Looks like someone's been spending too much time around the transmitter array (your icon...)?

I'm a receiver guy, almost completely next generation cryogenic receiver R&D these days.  That picture was from my trip out to New Mexico at the VLA to teach micro-assembly and wire bonding to the techs out there.

Although, maybe you're half right because that array is featured in this movie...

Any old kind, 5 or 10% tolerance.  Precision?  What's that?     ONLY if called for, in my book - and I've seen NO stomps requiring precision, ever...only test equipment like special oscillators used to calibrate things, and the like...I'd buy them then, if I needed them.

Many ppl use standard carbon composition type, or wire wound.  I prefer good ol' fashioned carbon comp.  Get 'em on Ebay, a whole set for like $5.   1/4 watt rating for 9V use, and 1/2W for some more specialized stuff like tube work.

I use 1% resistors a lot only because on the scale I build things the cost difference in negligible and I don't want tolerances to be working against me when I'm troubleshooting, BUT... what he said, it shouldn't really make any difference, save yourself some dough.

[duck_arse]

gibson - a doctor once told me to take aspirin, because "it reduces the swelling". and since then, whenever I get the swelling, I get the asprin.

butcher - please don't mention useful, you'll ruin my reputation.

and wavley - has anyone ever told you a story along the lines of: just after the war, when radar was still new-ish, "the boys", on a friday evening before going out on the town, would tilt the dish down, power up and stand in front for a 'short while' to kill the swimmers?

that'd get the white dielectric material going.

[Brisance]

I love the regular 5% carbon comp resistors, because the value is clearly visible and easy to read. I am using 1% for now though, because I picked up a kit really cheap from china. I despise them as the blue paint is so dark on them it's hard to read and I mostly verify 'em with a DMM.

They are cheap though:
http://www.aliexpress.com/item/Free-Shipping-Total-600pcs-1-1-4W-Metal-Film-Resistor-Assorted-Kit-30-Values-10-Ohm/1430424968.html

[GibsonGM]

I have to agree, the blue ones are hard to read and ANNOY me to no end!  So I shy away.  1%, 5% - it's all good. I don't know about 10%, that's going a little out there, for me, LOL.   

Nice occupation, Wavley!!  Must be fun; I used to work project management in environmental cleanup (plan, install treatment systems with pumps, filters and the like)..loved it, but office politics sucked.  I paint houses in a very rural area of Maine now, much happier!   I do miss the tech stuff, tho!    You must have tons and tons of cool inside 'tricks of the trade', maybe some that apply here....watch out for prime numbers, though! 

Where's the 'swelling', Duck?  I've tried aspirin, but it didn't work.  Esp. for my swollen head when I tell a noob something....the only cure for that is a 'master' coming along and quickly pointing out where I've made a mistake, ha ha! 

[wavley]

gibson - a doctor once told me to take aspirin, because "it reduces the swelling". and since then, whenever I get the swelling, I get the asprin.

butcher - please don't mention useful, you'll ruin my reputation.

and wavley - has anyone ever told you a story along the lines of: just after the war, when radar was still new-ish, "the boys", on a friday evening before going out on the town, would tilt the dish down, power up and stand in front for a 'short while' to kill the swimmers?

that'd get the white dielectric material going.

Hah!  You made a Cosmic Microwave Background Radiation joke, you're a nerd... wait, what does it mean if I got it?  Nevermind.

Ironically, my original job in radio astronomy was working for the team that designed and built the low noise amplifiers for WMAP, they mapped the CMBR.

I have to agree, the blue ones are hard to read and ANNOY me to no end!  So I shy away.  1%, 5% - it's all good. I don't know about 10%, that's going a little out there, for me, LOL.   

Nice occupation, Wavley!!  Must be fun; I used to work project management in environmental cleanup (plan, install treatment systems with pumps, filters and the like)..loved it, but office politics sucked.  I paint houses in a very rural area of Maine now, much happier!   I do miss the tech stuff, tho!    You must have tons and tons of cool inside 'tricks of the trade', maybe some that apply here....watch out for prime numbers, though! 

Where's the 'swelling', Duck?  I've tried aspirin, but it didn't work.  Esp. for my swollen head when I tell a noob something....the only cure for that is a 'master' coming along and quickly pointing out where I've made a mistake, ha ha! 

I love my work, sometimes hate my job, coworkers can really make things suck sometimes.  There's a lot that applies both ways.  I was a pro audio repair guy before this, my wife saw the job post and convinced my to put my resume in.  I interviewed, they put me in front of a microscope and handed me some tweezers and some tiny parts and asked me if I could place things like they were on a drawing, I could, they offered me a job.  I said "I think there's a big difference between the Crown Macro 5000s I work on and cryogenic amps you build under a microscope, you sure?"  My then future boss/mentor replied with a thick Polish accent "Amps is amps."  He was more right than you know, my tube amp knowledge helps me with my job and vice versa, plus since my skill set is different than schooled microwave guys I often come up with novel solutions to GHz stuff that are just normal for audio.  I think differently than my coworkers.

[GibsonGM]

^ Ha, awesome!  I bet you do have a different approach.  I have a good friend, an EE, and he is ALWAYS giving me WRONG "tips" regarding audio...his forte is hotel automation, now at Disney automating rides etc....great field, but without knowing the little "gotchas!" I mentioned above, you can screw things up pretty well.     

Like not contemplating what affect a cap has on frequency when coupling things ("any fair value cap will do, to block DC"), that sort of stuff.  Looking for precision in some areas that are important in another field/application, but are meaningless at audio - you get the gist.

I started in radio, just making SW receivers and things.  Gives you an appreciation for what those little capacitances can do, ha ha...esp. the ones that you aren't very aware of (interelement, parasitics), and when caps act like inductors    

[Butcher]

three pages from a messed up first post... must be some kind of record there.

I am learning though!
Aspirin reduces swelling
Microwave radiation kills baby batter
I was gonna order the wrong resistors
This thread no longer has anything to do with capacitors

[LightSoundGeometry]

ha! we just started atomic nucleus and radioactivity today in physics class - not much electricity involved that we discussed other than the table of elements, the outer shell and the charges of the atoms (principle quantum and the strong force).  we just finished up an overview of thermal dynamics and Newtons law of Cooling..Q=mc ΔT,  Q=mLv and Q=mLf

[duck_arse]

three pages from a messed up first post... must be some kind of record there.
.......
This thread no longer has anything to do with capacitors

the tracks were originally laid down, but the carriages seem to have been shunted to a siding before the first post. it's not our fault this time, and you may have broken the "fewest posts to complete derail" record.



also: capacitors.

[PRR]

> next stupid question

Nobody is born knowing this stuff, we all had to ask the ignorant questions.

5% carbon-film.

I grew up with carbon composition, and they work, but CF is more stable and less hissy than CC.

Some say there is "a mojo" in composition. I think it is like using old tires on your classic car--- new tires are made a little better and are much less potential trouble. Your choice. But CC is now costly and CF is a glut on the market. Leave the cork-sniffing of india-ink, titanium film, and coal/clay (carbon composition) for when you know almost everything and are looking for minor ways to shift flavor or just amuse yourself.

In pedals, 1/8 Watt is ample almost everywhere. My fat fingers prefer 1/4W for small stuff. When I feel really clumsy, or am working in power or tube circuits, I use 1/2W where it does not matter, 1W and 2W and up where the resistor has real work to do.

[wavley]

> next stupid question

Nobody is born knowing this stuff, we all had to ask the ignorant questions.

5% carbon-film.

I grew up with carbon composition, and they work, but CF is more stable and less hissy than CC.

Some say there is "a mojo" in composition. I think it is like using old tires on your classic car--- new tires are made a little better and are much less potential trouble. Your choice. But CC is now costly and CF is a glut on the market. Leave the cork-sniffing of india-ink, titanium film, and coal/clay (carbon composition) for when you know almost everything and are looking for minor ways to shift flavor or just amuse yourself.

In pedals, 1/8 Watt is ample almost everywhere. My fat fingers prefer 1/4W for small stuff. When I feel really clumsy, or am working in power or tube circuits, I use 1/2W where it does not matter, 1W and 2W and up where the resistor has real work to do.

As always, Paul is right.  As an interesting side note there is a use for CC resistors as detailed in this Geofex article by R.G. http://www.geofex.com/article_folders/carbon_comp/carboncomp.htm you'll note that the use is very specific and there are trade offs to the benefits.

Ironically, I use the tires on a classic car example often and a little differently, it goes "You wouldn't drive a 66 Mustang with it's original set of bias ply tires and tank of gas would you?  It's asking for trouble.  Why would you play a 66 Twin with it's original filter caps?  Like tires and gas, caps and tubes are consumables."

But I digress, you should futz around with 9v stompboxes for a while before you start poking around in tube amps.

[GibsonGM]

I was going to come back and re-state that, ha ha...yes, carbon film, my mistake, and thanks for catching it, Paul.   Guess I have my head stuck in the old tubes!  Next I'll call your caps "condensers"!  

Well agreed, carbon comp's are noisy!  Some use them for 'mojo' in their tube builds...sure, go for it but not me.   You'd pay MORE to get the claimed mojo, too, lol.     I like the size of 1/4 watt, and easier to read for an old man  

[Butcher]

> next stupid question

Nobody is born knowing this stuff, we all had to ask the ignorant questions.

5% carbon-film.

I grew up with carbon composition, and they work, but CF is more stable and less hissy than CC.

Some say there is "a mojo" in composition. I think it is like using old tires on your classic car--- new tires are made a little better and are much less potential trouble. Your choice. But CC is now costly and CF is a glut on the market. Leave the cork-sniffing of india-ink, titanium film, and coal/clay (carbon composition) for when you know almost everything and are looking for minor ways to shift flavor or just amuse yourself.

In pedals, 1/8 Watt is ample almost everywhere. My fat fingers prefer 1/4W for small stuff. When I feel really clumsy, or am working in power or tube circuits, I use 1/2W where it does not matter, 1W and 2W and up where the resistor has real work to do.

Very informative, thank you.
Do you have a manufacturer you prefer?

[Butcher]

three pages from a messed up first post... must be some kind of record there.
.......
This thread no longer has anything to do with capacitors

the tracks were originally laid down, but the carriages seem to have been shunted to a siding before the first post. it's not our fault this time, and you may have broken the "fewest posts to complete derail" record.



also: capacitors.

Yes I only have myself to blame. 

[Butcher]

I love the regular 5% carbon comp resistors, because the value is clearly visible and easy to read. I am using 1% for now though, because I picked up a kit really cheap from china. I despise them as the blue paint is so dark on them it's hard to read and I mostly verify 'em with a DMM.

They are cheap though:
http://www.aliexpress.com/item/Free-Shipping-Total-600pcs-1-1-4W-Metal-Film-Resistor-Assorted-Kit-30-Values-10-Ohm/1430424968.html

That seems like a good deal, think I'll place an order.

[PRR]

> Do you have a manufacturer you prefer?

Perfectly good carbon-films are made in back alleys in asian cities. If there is even a name on the door, you'll never know.

The field is not rife with rejects, but you can get some mis-described or just nasty parts. I think the tip is to Know Your Supplier. Small Bear stocks parts which make pedal builders happy. DigiKey and Mouser stock way too many resistors in way too many types for all sorts of builders, but they are all good quality. The gang here knows other sources. Too-cheap baggies on eBay or ChinaMart may not be what you expect. And resistor costs are too small to fool with "bargains", IMHO. Mis-marked resistors, or an "assortment" which is all 68K, spoil your day.

[tubegeek]

I love my work, sometimes hate my job, coworkers can really make things suck sometimes.  There's a lot that applies both ways.  I was a pro audio repair guy before this, my wife saw the job post and convinced my to put my resume in.  I interviewed, they put me in front of a microscope and handed me some tweezers and some tiny parts and asked me if I could place things like they were on a drawing, I could, they offered me a job.  I said "I think there's a big difference between the Crown Macro 5000s I work on and cryogenic amps you build under a microscope, you sure?"  My then future boss/mentor replied with a thick Polish accent "Amps is amps."  He was more right than you know, my tube amp knowledge helps me with my job and vice versa, plus since my skill set is different than schooled microwave guys I often come up with novel solutions to GHz stuff that are just normal for audio.  I think differently than my coworkers.

I LOVE THIS STORY!

[Wavley's future boss/mentor replied with a thick Polish accent "Amps is amps."] is a possible new sig.....

[Butcher]

just found an app on my iPhone for resistor colour codes. much simpler!!

[Saint Louis Toneworks]

nothign like building 3 in a row then wasting 5 in a row ..im out of materials as i wasted everything all pissed off trying to get my pedal together..how can some come together and then repeat the same process with no luck at all ..

[Butcher]

nothign like building 3 in a row then wasting 5 in a row ..im out of materials as i wasted everything all pissed off trying to get my pedal together..how can some come together and then repeat the same process with no luck at all ..

I'll let you know when I build more pedals.