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OMG !!!!! how hard is it to read a meter ?


Assuming that the thing is calibrated for the power level the meter is 'in', and going by the pictures in the first post, 10 watts and 6-7 watts. Which is about 'average' accuracy for almost any brand of meter. The 'scale'/marks on the scales are not congruent, but the 'numbers' attributed to those marks are (see the diagonal marks between the two 'scale' lines, notice how they are not all the same diagonal 'angle' for each consecutive mark? Typical for different 'scales' on a D'avarsenal(sp) meter.).

You're right, the user should learn how to read the meter. RTFM, simple with just a tiny bit of thinking. Is the meter 'junk'? Nope, just about average for accuracy for any meter. Don't like the 'Radio Shack' name on it? Cover it up, then don't worry about it. The largest inaccuracy in reading meters is usually with the one doing the reading...
- 'Doc
 
The RS power meter scaling “L” (low) hash mark is for the readings under 20 watts (20 watt scale). The power meter scaling “H” hash mark is for the readings over 20 watts (200/2000 watt scale). The manual gives an accuracy reading of +/- 10% per each scale. It does not indicate if this is full scale (but I assume it is) or of actual reading. this does not include operator error in the readings, but the huge margin of +/- 10% should allot for that.

Most meters compliant to ISO 17025 will have the uncertainty levels for the scale, and actual reading. The two numbers are then placed into computation for the max uncertainty levels. These accuracy readings are only good/guaranteed if the meter is calibrated every 12 months (in some CE conditions every 6 months). In some instances the +/- % accuracy can improve if these guidelines are met and they meet calibration standards according to that ISO standard. In real-world environments the meters can be subjected to shock and vibration and deterioration/degradation that could also alter readings over time.

Of course the RS meter has no traceability or calibration paperwork, so the 10% is good enough specs for the lay person (maybe not enough for FCC determining actual ERP). The meter scaling does not account for parallax error; some of the meters have the mirror or reflective background so the user can look at the needle straight ahead with little or no angular view distortion.

I would not use the 200 watt scale to read the 6-7 watts as displayed due to meter scaling (lack of hash marks) and the sensitivity (or lack of) of the circuitry and movement at those low readings.

;)
 
BOOTY MONSTER said:
http://www.cbradiotalk.com/viewtopic.php?t=13733

maybe this is why some say they get 1200-1600 watts out of a 2x4 class C amp .
Click to expand...

A volted 2x4 will do 1600 watts peak on a Dosy.
 
psycho said:
BOOTY MONSTER said:
http://www.cbradiotalk.com/viewtopic.php?t=13733

maybe this is why some say they get 1200-1600 watts out of a 2x4 class C amp .
Click to expand...

A volted 2x4 will do 1600 watts peak on a Dosy.
Click to expand...

I had cheap watt meters and they never showed the watts these guys see.
 

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