K2 Resistor R9 Question

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K2 Resistor R9 Question

pagoglia
I began assembly of our K2 this evening, so we are in the early stages.  The control board assembly calls  for several 1% resistors, and it calls for testing these resistors with an ohm meter.  Three of the four checked out well.  The fourth, R9, an 806k resistor, checked in at 435k on one  ohm meter and just over 520k ohms on a different ohm meter.  We opted not to solder it in until we hear whether it will still do the job or should we request a replacement, or is there another way to test it.

Thanks

WN2K
Paul
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Re: K2 Resistor R9 Question

Don Wilhelm-4
  Paul,

The 1% resistors on the control board are there to permit correct
voltage and current measurements, so they should be "spot on".

But it all depends ---
Some ohmmeters will give a false indication at the extremes of their
ranges - what range were you using when you measured the 435k resistor?  
If it was not mid-scale, then change the range and measure again - if
you were relying on auto-ranging, switch to manual range and verify.

Second question is "what do the color codes indicate?"  While there can
be errors in the color codes, that is quite unusual.

If you have another resistor with a value between 470k and 1 megohm, use
that to make a sanity check on your ohmmeter.  If that value is also
quite different from the value marked on the resistor, suspect your
ohmmeter, but if the values track with the color codes on the
resistor(s), you can be confident that you have a 1% resistor that is
marked incorrectly.  If so, send a note to [hidden email] and ask
for a replacement.

73,
Don W3FPR

On 11/30/2010 7:57 PM, Paul Agoglia wrote:
> I began assembly of our K2 this evening, so we are in the early stages.  The control board assembly calls  for several 1% resistors, and it calls for testing these resistors with an ohm meter.  Three of the four checked out well.  The fourth, R9, an 806k resistor, checked in at 435k on one  ohm meter and just over 520k ohms on a different ohm meter.  We opted not to solder it in until we hear whether it will still do the job or should we request a replacement, or is there another way to test it.
>
> Thanks
>
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