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SWR\Power meter

If you are just using them for any HF Band I use AUTEK WM-1 meters.I own (3) of them because they are reliable & no calibration & they read both output power & SWR all at once.They are no longer in business but there sometimes are found For sale.They read Average or Real PEP output unlike the cheap Dosy,Palomar,PDC & other meters.It depends upon which version you find but some of the meters are lit & some are not but they are the same meter.I also use a WELZ SP-600 with an added PEP kit for 6 meters & it is a very accurate meter & it covers,HF,VHF,& UHF all in one meter.

SIX-SHOOTER
 
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As time goes on I have less use for a pep meter. Hit the tune bu
Riverman said:
Dadgumit!
They're supposed to be the best thing since sliced bread.
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Don't sweat the small stuff. When my palstar pm200a says 1500 pep, my bird 43 w/ pep kit says 1750. I decided to trust the palstar. ;)

Seriously though. I have never had two watt meters that agreed with one another across the scale. They were all close enough though. The top O the line bird is accurate within 5% but only at full scale. At less than full scale, who knows?
 
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I've read that the bird meters are most accurate in the middle of the sweep. As you get closer towards the edges is where the discrepancies are highest.
 
Say for example you have a voltmeter advertised as being plus or minus 10%. That has to mean "of full scale" in order to mean anything. Now, say this meter has a full-scale value of 100 volts. Ten per cent of a hundred...carry the 6... OK. With a known-good 100 volts applied, the meter can read anywhere from 90 to an extrapolated 110 volts and still meet the manufacturer's specifications. Similarly, if you're trying to read a known-good ten volts, the meter can read anywhere from zero to twenty volts and meet the specs. Bird meters must be used with a calibrated slug of realistic power and frequency range.
 
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Analog meters are just not as accurate as a digital meter. So many things can affect the analog meter readings, parallax, and operator error being the most common.
If you have ever "pegged" the meter you have caused damage to the meter.
 
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999 said:
I've read that the bird meters are most accurate in the middle of the sweep. As you get closer towards the edges is where the discrepancies are highest.
Click to expand...

A decent meter will state its accuracy at full scale deflection in any paperwork that comes with it. The majority are only truly accurate at or near FSD.
 
The meters are calibrated at a minimum of three reading through out the entire scale to maximum deflection...meaning any one of those points of calibration have to be within the tolerance stated. If it does not meet those parameters then you can not calibrate it properly and it is rejected. So that statement is not true. If you have a meter that reads only accurate in the middle or at the top then you are dealing with a uncalibrated meter.
 
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If you would like to know more on the matter you can look at ANSI/NCSL Z540-1-1994. That is the spec that calibration labs have to follow. You can use a NIST STANDARD or transfer standard for your instrument calibrations...either way there is a 4:1 test accuracy ratio simply meaning whatever instrument you are calibrating has to be done by another instrument that is 4 times more accurate. And talk about compounding percentages that spec also says that the collective uncertainty of the measuring standards shall not exceed 25% of acceptable tolerance for each characteristic. lol.
 
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