Author Topic: CWOP / MADIS Barometric Pressure issue  (Read 765 times)

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Offline wegenmaier

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CWOP / MADIS Barometric Pressure issue
« on: December 26, 2020, 05:10:45 PM »
I am sending through AmbientCWOP and just got a message that my MADIS data is "off". I am WB4ZUT (CWOP ID) using an Ambient WS-2092C station and they are telling me to compare to a profession station in my area. I have calibrated with the airport which is only 2 miles from me, so I am not sure how more accurate i can be.
Any suggestions on how to resolve this. My current barometric pressure is 30.03 and so is KEVV airport in Indiana. Appreciate any help.
Walt / WB4ZUT

Offline Clarkey

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #1 on: December 26, 2020, 06:00:22 PM »
Hi Walt,

Currently you are reporting 30.37 and KEEV is reporting 30.04 ... is your altitude correction being done twice possibly? I'm not sure if Ambient changes/adjusts this at all ????

Clarkey
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Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #2 on: December 26, 2020, 06:10:18 PM »
My current value is 30.01, so not sure why this is so far off.
I'm at 118 meters


Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #4 on: December 26, 2020, 06:15:12 PM »
Do i have to go in and recalibrate or recalculate my absolute barometric pressure or just go in and set my relative pressure to my airport? I'm currently 30.01 and my airport about which read it about an hour ago is at 30.04

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #5 on: December 26, 2020, 06:20:31 PM »
I see about 4 different pressures...which is the correct one and which do I have to recalibrate?
I have the d/l on how to claibrate barometric pressure, but the manual talked about changing absolute pressure and i think I may have goofed there.
Should I start with the manual again and calibrate absolute again, or just adjust according to my airport?
I'm very new at this and likely messed with the absolute and messed up. Give a place to start and I will try again.
Walt

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #6 on: December 26, 2020, 06:23:13 PM »
Currently my absolute is 29.95 and my relative is 30.02

Offline CW2274

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #7 on: December 26, 2020, 06:28:45 PM »
Currently my absolute is 29.95 and my relative is 30.02
That may be what you see at home, but that's certainly not what's being put online. Your relative as of the 1720 op is 30.39 inHg and absolute 29.94 inHg.

Offline CW2274

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #8 on: December 26, 2020, 06:34:01 PM »
Looks like you're reporting online ~360 ft too high.

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #9 on: December 26, 2020, 06:35:31 PM »
Ok, I just went in and reset the absolute back to factory settings, then checked the airport and matched theirs to mine. I am now reading 30.03 and airport is reading 30.02.
I think I messed things up when I went in and tried to change the absolute. By reseting it to factory settings, I hope I fixed my error. Then, making mine the same as the airport 2 miles away, I should be back in compliance or same as airport. Can I use the same link to see what it reads now and which of the 4 pressures do I look at?
Walt/WB4ZUT

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #10 on: December 26, 2020, 06:39:09 PM »
My elevation is 388.92 ft. I think I messed it up when calculating my altitude.
Since I corrected it about 8 minutes ago...maybe it is reading true now?
I will click on those former links you sent, but again, new at this and not sure which values I need to concentrate on to see the error. Sorry for not knowing more.
Walt

Offline CW2274

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #11 on: December 26, 2020, 06:40:50 PM »
Can I use the same link to see what it reads now and which of the 4 pressures do I look at?
Walt/WB4ZUT
Sure, sea level pressure, also known as SLP or MSLP.

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #12 on: December 26, 2020, 06:44:14 PM »
Since I made the adjustment, my pressure has changed considerably. Our relative pressures are now matched. Not sure I fixed the problem, but all appears much closer and more accurate to my novice abilities. Can you take another look and see if I'm better now? Altitude more accurate?

Offline CW2274

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #13 on: December 26, 2020, 06:52:46 PM »
Can you take another look and see if I'm better now? Altitude more accurate?
Looks like you're still a touch high, wait for the next airport op which will be at 1754 (probably won't display til the top of the hour or so). Compare then.

Offline wegenmaier

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #14 on: December 26, 2020, 06:58:40 PM »
How do I adjust the altitude?  Make changes to the Absolute pressure? And which way do I go and how much.

Offline CW2274

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Re: CWOP / MADIS Barometric Pressure issue
« Reply #15 on: December 26, 2020, 07:01:36 PM »
How do I adjust the altitude?  Make changes to the Absolute pressure? And which way do I go and how much.
I'm a Davis owner, so no help here. Someone else will.