| Author |
Message |
    
vernonott
| | Posted on Friday, June 01, 2001 - 10:14 am: | 
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307 : Why do all of my Dosy meters read different outputs on different scales? On the 300 watt scale I may be putting out 250 watts,if I switch to 1000 watt scale I may be putting out 300 watts.Isn't a watt a watt? |
307 (307)
| | Posted on Friday, June 01, 2001 - 10:56 am: |
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Anther common problem , when these meters are built they are built in production. Each meter is not calibrated however one in probably every 50 or so are. This is called a pull check (in production). What happens is a "standard" meter is built and the "settings" on the pots are marked. when they install the new pots into the production line , they "eyeball" them to match the standard. This cuts several production positions that would have to take place if everyone was calibrated. The end result is NO two are the same....Now if you buy a BIRD or RF CONCEPTS meter , they are ALL calibrated and you pay for it as well. Thats why they are so much money , NOT the electronics in them but they are CALIBRATED to be really exact. This is why I always argue the fact one CB shop gets 50 watts out of the same radio that I get 25 watts out of. I have Calibrated equipment and I have it calibrated every 6 months. |
bullet
| | Posted on Saturday, June 02, 2001 - 2:18 am: |
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the rf sampling sections of the docy meters
are extreamly small and very cheap in make, as is the case with about all of the cb watt meters in production.these meters are relative watt meters
meaning they just put ya in the ball park.thats it
now Struthers,Bird and a few others make meters
that are very acurate and have well made rf sampling sections and very nice metering. not alot of flashy stuff like lights,chrome knobs,switches ect ect but its the closest thing to dead on metering you will get out of the box. besides checking the voltage/current and doing the math P=E x I (watts=volts x current)
so you do get what ya pay for when ya buy a struthers or a bird watt meter if you want a good
reading anyway. alot of guys dont take radios
that serious and just want a meter to use for swr checks and ball park wattage checks and this is were the doscy shines.again ya get what ya pay for.
later bullet |
Dutchman
| | Posted on Saturday, June 02, 2001 - 1:47 am: |
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307 is dead on about uncalibrated meters. My dad was a meter tech for almost 30 years before he retired. He was the type of guy that 307 would send his equipment to to be certified (he did NBS certs)
If it isn't calibrated and aligned right....you are getting"close guesses&approximations"...not accurate readings.
Find a shop near you that does meter repair and certification....a meter like yours can be done fast and relatively inexpensevely if you ask!! |
vernonott
| | Posted on Saturday, June 02, 2001 - 7:49 pm: |
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Dutchman : Sounds like good advice to me.Thanks |
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