Calibrating Power?

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KC7RBW
Posts: 159
Joined: Wed Nov 20, 2019 1:23 am

Calibrating Power?

Post by KC7RBW » Fri May 15, 2020 8:16 pm

Is there a guide describing how to calibrate power levels?
And are there relatively inexpensive tools to measure RF power that people like?

There's a repeater around 8km away that I allegedly hit really well when my radio says it's at 50mW so I'm wondering if my calibration is off.

VK3KYY
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Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Calibrating Power?

Post by VK3KYY » Sat May 16, 2020 6:04 am

Its simple.

1.Connect the USB cable to the radio
2.Run the CPS
3.Open the Calibration screen and read the data from the radio
4.Set the radio to 1W.
5.Measure the power, and adjust the 1W (Low power) power number for the frequency you are transmitting on.
If the power is too low, increase the number, if the power is too high decrease the number.
6.Write the new calibration data to the radio
7. Repeat the process from Step 5 until the radio transmits the power you level you have set. (1W or 5W)

8.Repeat steps 5 to 7 for the High power values with the radio set to 5W

9. Repeat steps 5 to 8 for every 5MHz section of the RF range you intend to use.

VK3KYY
Posts: 7473
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Calibrating Power?

Post by VK3KYY » Sun Jul 19, 2020 10:57 pm

Question moved to this topic as it contains the answer (see above).

BTW. Its not possible to calibrate the Rx RF sensitivity, as there is no hardware in the radio to do this.

VK3KYY
Posts: 7473
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Calibrating Power?

Post by VK3KYY » Mon Jul 20, 2020 6:37 am

kewinxx wrote:
Mon Jul 20, 2020 6:29 am
Ciao e possibile fare una guida con i vari passaggi di calibrazione rx tx???
Translates to
Hello is it possible to make a guide with the various calibration steps rx tx ???

VK3KYY
Posts: 7473
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Calibrating Power?

Post by VK3KYY » Mon Jul 20, 2020 6:38 am

No.

I can't see how I can make the instructions more simple...



1.Connect the USB cable to the radio
2.Run the CPS
3.Open the Calibration screen and read the data from the radio
4.Set the radio to 1W.
5.Measure the power, and adjust the 1W (Low power) power number for the frequency you are transmitting on.
If the power is too low, increase the number, if the power is too high decrease the number.
6.Write the new calibration data to the radio
7. Repeat the process from Step 5 until the radio transmits the power you level you have set. (1W or 5W)

8.Repeat steps 5 to 7 for the High power values with the radio set to 5W

9. Repeat steps 5 to 8 for every 5MHz section of the RF range you intend to use.

dl9sec
Posts: 29
Joined: Sun Jun 28, 2020 11:32 am

Re: Calibrating Power?

Post by dl9sec » Sun Feb 28, 2021 4:06 pm

VK3KYY wrote:
Sat May 16, 2020 6:04 am
Its simple.

1.Connect the USB cable to the radio
2.Run the CPS
3.Open the Calibration screen and read the data from the radio
4.Set the radio to 1W.
5.Measure the power, and adjust the 1W (Low power) power number for the frequency you are transmitting on.
If the power is too low, increase the number, if the power is too high decrease the number.
6.Write the new calibration data to the radio
7. Repeat the process from Step 5 until the radio transmits the power you level you have set. (1W or 5W)

8.Repeat steps 5 to 7 for the High power values with the radio set to 5W

9. Repeat steps 5 to 8 for every 5MHz section of the RF range you intend to use.
Hi Roger,

could you give some further information please?

Is the power measured in FM mode?
What to do with the "DMR Tx 4FSK" values?

Thank you.

73, Thorsten

BTW: It is not possible to search the forum for the word "calibration" ("...too common words: calibration"). It was only possible via the google site search...

G4EML
Posts: 919
Joined: Sat Nov 16, 2019 10:01 am

Re: Calibrating Power?

Post by G4EML » Sun Feb 28, 2021 5:13 pm

Yes, with amateur test equipment you can only really test the power when set to FM.

"DMR Tx 4FSK" values... Don't touch them! Any adjustment needs a proper DMR test set. If you have one than you should already know what to do.

Colin.

G4EML
Posts: 919
Joined: Sat Nov 16, 2019 10:01 am

Re: Calibrating Power?

Post by G4EML » Sun Feb 28, 2021 5:35 pm

This is a good video explaining why it needs a proper test set to test and adjust DMR signals...

https://www.youtube.com/watch?v=GZWies3Rb4k


Colin.

dl9sec
Posts: 29
Joined: Sun Jun 28, 2020 11:32 am

Re: Calibrating Power?

Post by dl9sec » Sun Feb 28, 2021 6:58 pm

Thank you very much for the information, Colin.

73, Thorsten

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