250 ohm resistors
Why are 250 ohm resistors for bread boards so hard to find?
Re: 250 ohm resistors
Because resistors are nearly always manufactured to fit into a standard series of resistor values by range. These ranges are known as E6, E12, E24, E48, E96 and E192. 250 Ohms doesn't exist in any of these standard ranges.urlonz wrote:Why are 250 ohm resistors for bread boards so hard to find?
See the table at the link below and select the nearest standard value...
http://www.logwell.com/tech/components/ ... alues.html
Unless the resistor is being used as part of a precision reference chain for some reason, its exact resistance probably isn't going to matter a great deal within 10% either way. Very loosely speaking, the lower the range you can select from, the cheaper it will be.
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Pithagoros
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Re: 250 ohm resistors
I have some, but they are chunky 1 watt jobbies. Can't remember ever having seen a 1/4W one.
If you need 250 ohm then do a bit of 1/r1 + 1/r2 and solder a couple in parallel.
If you need 250 ohm then do a bit of 1/r1 + 1/r2 and solder a couple in parallel.
Re: 250 ohm resistors
A 270Ω resistor would be the nearest preferred value. It's only 8% higher than 250Ω . A properly designed circuit won't be upset by than small a change in values.
PeterO
PeterO
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Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson