Hi Moshin,

The project was based on using the AD8307 power detector module from SV1AFN. You will find a link HERE

The module is based on the AD8307 application note, so should be easy to recreate. NB: I don’t recommend using the cheap AD8307 modules from eBay (China) as, in my experience, they use substandard components that make accurate calibration very difficult.

Regards,

Mike

Hi Mike

Thanks !

73
Yoram
4X1YS

Hi Yoram,

I sold the original article to Practical Wireless magazine so they own the copyright. I suspect the link you were given was an illegal copy, hence its removal.
The AD8307 module I used was the one in the link below by Makis SV1AFN. Makis makes a range of useful RF modules. If you follow the link he has the AD8307 data sheet as well as notes on its performance. That should give you all you need.

AD8307 Module

Regards,

Mike – G4WNC

( http://techham.altervista.org/Arduino-Ham/A%20Look%20at%20the%20Arduino.pdf )

And unfortunately the link does not work….
Is there a link to the article Please ?

Thanks again
73
Yoram
4X1YS

Hi Mike

Thanks for the quick response
Indeed changing the parameter did the job
simply incredible !
This is a nice upgrade to my dummy load .
When I finish the job I will be happy to send pictures of the final product .

Thank you so much Mike !!

73
Yoram
4X1YS

Hi Yoram,
In the Arduino sketch, I compensate for the loss in the RF tap by altering the intercept point used for the power calculation. The intercept point is the power input required by the AD8307 to give a theoretical 0V output. This figure is calculated from the power vs voltage slope of the AD8307. However, useful results can be had by using the nomonal intercept point of -88dBm. For a 40dB power tap from the transmitter, that figure needs to change to -44dBm but for your 60dB tap/attenuator the intercept will be -24dBm.
To adapt the code for your system, do the following:
Find the “// initialise the variables” section of the sketch
Find the line that begins: float intercept =
Change that line to read: float intercept = 24.0;

That’s it!

Regards,

Mike – G4WNC

73
Yoram
4X1YS