Yes, you should round up to 3.8 volts. There will be some variability
due to DMM differences, and some further variability due to component
tolerances. When a value like 3.8 is specified, rounding to one
significant digit is what is intended.
Most of the values listed in the DC voltage charts are the result of
actual measurement from a properly working unit, so pay attention to the
conditions listed for any measurements (band, power setting, supply
voltage, etc.) - do not use more decimal places than what is listed in
the chart even though your DMM may show the value to a large number of
decimal places. A variation of 10% is usually within the expected
tolerance range.
73,
Don W3FPR
MGFoster wrote:
I've reached the first DC Voltage Check in the RF Board assembly and
for the AF amplifier (LM386N-1, component U3) pin 5 check the Voltage
should be between 3.8V and 4.2V. My DMM measured 3.786V. Is this
significant, or should I just round up to 3.8V? All other voltage
check points were within predicted range.
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