here's a loaded question?

Started by sbgodofmetal, April 08, 2011, 10:27:17 PM

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LucifersTrip

#20
Quote from: R.G. on April 11, 2011, 12:27:18 AM
Quote from: LucifersTrip on April 11, 2011, 12:17:47 AM
This brings up a question I've always pondered but never sat down to figure out.  How many different caps and transistors would it take to have every value you need if you can make combinations of 2, 3, 4 etc in series or parallel?  Those ceramic caps and 1/4 watt resistors are so small, I have no problem putting multiple ones together and fitting them in the same spot that one would take up on a perfboard.
Well... it depends on what limitations you put on how many resistors/caps you will stand for in combinations. If you have no limit on the number of resistors you'll allow to be series/paralleled, the obvious answer is only one value is needed, and it does not matter what it is.  :icon_biggrin:

The answer is different if you restrict the series/parallel combination to no more than 100 resistors in a clot, no more than 10, no more that 4, etc. All different answers, and the answer varies again if you restrict how closely you have to hit the target value.


I would start with something simple and reasonable, using only a combination of 2 components with a 10% closeness target.
I could have probably figured that out a decade ago after finishing my masters in statistics, but that info is gone...

A programmer could do this easily by just looping all the calculations & checking the answers against the complete value set.

It'd be great to see a table/chart of all the values that can be gotten by combining  2 caps in series/ 2 resistors in parallel, using  just common values of each. Obviously, a parallel cap/ series resistor chart would be unnecessary. Again, a programmer could generate that very quickly.
always think outside the box

slacker

#21
Quote from: LucifersTrip on April 11, 2011, 12:33:15 AM
It'd be great to see a table/chart of all the values that can be gotten by combining  2 caps in series/ 2 resistors in parallel, using  just common values of each. Obviously, a parallel cap/ series resistor chart would be unnecessary. Again, a programmer could generate that very quickly.

Like this you mean http://www.diystompboxes.com/smfforum/index.php?topic=76470.0  ;) Not every value I admit, but I think it gives most of the values you're likely to need to build stompboxes.

LucifersTrip

Quote from: slacker on April 11, 2011, 02:56:31 PM
Quote from: LucifersTrip on April 11, 2011, 12:33:15 AM
It'd be great to see a table/chart of all the values that can be gotten by combining  2 caps in series/ 2 resistors in parallel, using  just common values of each. Obviously, a parallel cap/ series resistor chart would be unnecessary. Again, a programmer could generate that very quickly.

Like this you mean http://www.diystompboxes.com/smfforum/index.php?topic=76470.0  ;) Not every value I admit, but I think it gives most of the values you're likely to need to build stompboxes.

No, not really...but, that's definitely on the right track. I wanted a full, easy to ready reference table.  I forgot I could do it easily in Excel, so here's a quick one for caps:
Capacitor series combo chart
always think outside the box

sbgodofmetal

well ya see i'm redused to cash in hand i.e. i have no credit card and do not qualify to get one i've tried, i usually never have enough to use a reloadable debit card and cant afford the fee's if i did, i have no bank accounts, don't trust paypal, and unless a store will order it i'm screwed, so i just shop radio shack and other various electronic parts providers, along with the various music shops around my area. at least until i can find a decent paying job somewhere i'm stuck with that
I'vE gOnE iNsAnE wItH hOrRiBlY lOnG iNtErVaLs oF sAnItY!!!!

Somicide

#24
not to be severely off topic, but there's no reason to not trust paypal.  Hell, I don't trust sites that don't support paypal!

regarding the debit/credit, most debit cards from major banks now carry a Visa or Mastercard logo, meaning they can be used at any online store that accepts them (read:  ALL of them).  That said, if you can secure yourself a checking account (~1hour of misery in a bank, IME XD ) then you're good to go for online ordering.

Just a thought.
Peace 'n Love