M7E not reading tags with external Antenna

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1

I have attached a Times7 5020 antenna to the M7E. We are using a Linux setup. The antenna can see 1 or 2 tags at times that are within 3 ft direct line of site.

With this setup I should be able to see hundreds at a time. Not sure what we are doing incorrectly .

Any help is appreciated.

2

Which one are you using? A5020 Series Some have -dBi

Have you increased the reading power?

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3

We are currently at 22. Do you think it needs to be 27 to read tags within 3 feet? We are using the antenna below. Thanks for the help.

Times-7 SlimLine A5020 Circular Polarized Antenna

https://www.atlasrfidstore.com/times-7-slimline-a5020-circular-polarized-antenna-fcc-etsi/?sku=60010&utm_medium=cpc&utm_source=google&utm_term=&utm_campaign=G±+03±+PMAX±+Antennas±+US±+Feed+Only±+E.E.&hsa_acc=4442410237&hsa_cam=21417594943&hsa_grp=&hsa_ad=&hsa_src=x&hsa_tgt=&hsa_kw=&hsa_mt=&hsa_net=adwords&hsa_ver=3&gad_source=1&gad_campaignid=21413567453&gbraid=0AAAAAD7Pc8GBrIS2Sf1Fyo2bCDCBmH3yk&gclid=CjwKCAiA3-3KBhBiEiwA2x7FdJrhXV9iUHHeYfwheECBE8Cs4g2OG7UheDVog_htS2U4T6rHHUF-YxoCsT0QAvD_BwE

4

Did you change the solder link on the M7E ?

I assume you are using the Jadak MercuryAPI. Can you share the example you use ?

5

Hi,

I work with Brad, and below is the code we’re using. We can connect to the reader successfully every time; however, tag reads are inconsistent — sometimes it detects tags, but most of the time it doesn’t find any.

import mercury
import time
from datetime import datetime

def connect_reader(uri, baudrate=115200, retries=5):
    last_error = None

    for attempt in range(1, retries + 1):
        try:
            reader = mercury.Reader(uri, baudrate=baudrate)

            # Small warm-up delay (important)
            time.sleep(0.5)

            return reader

        except Exception as e:
            print(f"[WARN] Reader init attempt {attempt} failed:", e)
            last_error = e
            time.sleep(1)

    raise RuntimeError(f"Failed to initialize reader after {retries} attempts") from last_error


# ---- main ----

reader = connect_reader("tmr:///dev/ttyUSB0")

# Apply configuration AFTER successful connect
reader.set_region("NA")
reader.set_read_plan([1], "GEN2")
reader.set_gen2_target(2)
reader.set_read_powers([(1, 2200)])

print(reader.get_gen2_target())
print("Reader Model   :", reader.get_model())
print("Serial Number  :", reader.get_serial())
print("Firmware       :", reader.get_software_version())
print("Antennas       :", reader.get_antennas())
print("Power Range    :", reader.get_power_range())
print("Temperature    :", reader.get_temperature())
print("\nReading tags...\n")

print(reader.read())

reader.start_reading(lambda tag: print(tag.epc, tag.antenna, tag.read_count, tag.rssi, datetime.fromtimestamp(tag.timestamp)))
time.sleep(1)    
reader.stop_reading()
6

Thanks , did you check the soldering link ?

Also try to see what happens if you change:

reader.set_read_plan([1], “GEN2”)
reader.set_gen2_target(2)
reader.set_read_powers([(1, 2200)])

to :

reader.set_read_plan([1], “GEN2”, read_power=2200)

7

Are you referring to an external power supply..Currently we are using the USBC power from the RasberryPi I have not connected an external power supply.

8

The issue is the external antenna…It is connected to the board…If we move the rfids withing abou 6” of the board we can see the RFIDs…If we put the RFID tags about 12 “ in front of the antenna we can not see anything..So it seems the antenna is not send / receving ..Any ideas on what might be the issue?

9

Hi Brad (@Brad_Amster ),

Using an external antenna has its own section in the docs. Please see the link below.

Your board should look like this (note the modified position of the zero Ohm resistor):

image
image259Ă—143 63.3 KB

I hope this helps,
Paul

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