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Hi there,

I have recently purchased the Simultaneous RFID Tag Reader (SRTR) - M6E Nano alongside with the external UHF RFID Antenna (TNC) for range improvement. For reading purposes it is connected to an Arduino Uno r3 module.
I'm creating an harvesting system so I can measure the power received in a load (from the system SRTR + external antenna) over the distance but my receiving antenna is tunned at a frequency of 915 MHz.
The question is: Do I have to configure the SRTR so that emmits that fixed frequency or there will be no problem?

Thank you in advance.
Hi cfernandes,

I am not sure I fully understand your application here. Are you reading the RFID tags with the M6E Nano and then transmitting the data via an RF connection running at 915MHz? If not, please elaborate a bit on what exactly you are trying to accomplish with the M6E Nano and the UHF Antenna.

The operating frequency range of the M6E Nano is 860-960 MHz depending on how it is configured. The frequency of the M6E Nano can be configured by selecting your region either in the Arduino library or in the Universal Reader Assistant software. The Design Guide and datasheet for the M6E Nano will have more information about that.
Hello TS-Mark,

My goal is to measure the the quantity of power transmitted by the system (M6E Nano + external UHF antenna) using an harvesting system, but the receiving antenna on the harvesting side is configured to operate only at 915 MHz.
My question is: do I have to configure the M6E Nano to operate at that fixed frequency in order to optimize the power transfer or since it has a wide range of frequency values it will not make any difference?

The FREE / available UHF frequencies are assigned differently in different regions in the world. The other UHF frequencies have been licensed for specific usage ( e.g. military, commercial etc.). As you use the M6E you MUST use the free frequency(ies) that is (are) available for your region to not interfere with licensed frequencies. A good article to read is ... egulations.

If you look at page 74 of the design guide you will see what frequencies fit with each region for the Nano. For some other regions Jadak has made special versions of the M6E, like M6e-PRC and M6e-JIC have different ranges for their Open region. 840 to 845MHz and 920 to 925 MHz for M6e-PRC, 915 to 925 MHz for the M6e-JIC.

The 915Mhz is available on the M6E-Nano as part of setting region 'OPEN'. However this is a hopping table. It will start with 859Mhz and if it does not find a tag within a certain time, it will increase with 100Khz and try again. After 15 times it will have reached 873Mhz. If still not successful, it will now start with 915Mhz and as long as not successful increase in 16 steps to 930Mhz. If that is not successful, and the READ request has NOT timed-out, it will start all over again. I am not sure this will serve your need. As described in the design guide page 74, one can adjust the default hopping table, but that instruction is NOT available in the Sparkfun driver, only in the Jadak Mercury API

But again.. you are ONLY allowed to use the FREE UHF frequency(ies) in the region the M6E is applied.