# RFID reader hookup problems with Redboard **URL:** \ **Category:** Arduino\ **Created:** [April 23, 2025, 8:12pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755 "2025-04-23T20:12:33Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [April 23, 2025, 8:12pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/1 "2025-04-23T20:12:33Z")
i am trying to hook up the RFID reader with a Redboard. I ![IMG_8105](https://canada1.discourse-cdn.com/sparkfun/original/2X/d/d5eec7e838acca4bccecee06aaa38383f3959ef7.jpeg) ![IMG_8104](https://canada1.discourse-cdn.com/sparkfun/original/2X/7/70aea1e3f71450869c528ecbc69f347753e13f99.jpeg) ![IMG_8103](https://canada1.discourse-cdn.com/sparkfun/original/2X/d/d80d4b953adb7d07fd628c5dd9e280f39e36ad6b.jpeg) n the hook guide they are using a redboard artimis. do i have to have that one? i get flickers form RX and TX , making me think the power is an issue on this board or a connection. i am needing help using this red board. ---
**Author:** ![darrellg](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/darrellg/32/3334_2.png) [@darrellg](https://community.sparkfun.com/u/darrellg)\ **Post date:** [April 23, 2025, 8:19pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/2 "2025-04-23T20:19:04Z")
Some solder on those pin header connections would be a good start if you suspect an intermittent connection. ---
**Author:** ![paulvha](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@paulvha](https://community.sparkfun.com/u/paulvha)\ **Post date:** [April 24, 2025, 7:24am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/3 "2025-04-24T07:24:48Z")
the RX and TX (pin 1 and 0) are the same as Serial / USB connection. Use pin 2 and 3 and softtSerial as in the examples sketches. Make sure the switch on the M7E is set to SER. P.s. You seem to have connected an external antenna, but you have not changed the onboard zero resistor RF to select the external antenna. look in the hookup guide of the M7E how to do that. ---
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [April 25, 2025, 11:33pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/5 "2025-04-25T23:33:08Z")
i have fixed the wired connection and i am getting reading from the external antenna, but its only from a few inches away, how to i improve the range ? ---
**Author:** ![TS-Russell](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/ts-russell/32/6092_2.png) [@TS-Russell](https://community.sparkfun.com/u/TS-Russell)\ **Post date:** [April 26, 2025, 12:24am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/6 "2025-04-26T00:24:50Z")
Check out [https://docs.sparkfun.com/SparkFun\_Simultaneous\_RFID\_Reader\_M7E/hardware\_assembly/#power-supply-considerations](https://docs.sparkfun.com/SparkFun_Simultaneous_RFID_Reader_M7E/hardware_assembly/#power-supply-considerations) first, then try increasing the dB using rfidmodule.SetReadPower() from the library [https://docs.sparkfun.com/SparkFun\_Simultaneous\_RFID\_Reader\_M7E/software\_setup/](https://docs.sparkfun.com/SparkFun_Simultaneous_RFID_Reader_M7E/software_setup/) ---
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [April 29, 2025, 8:11pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/7 "2025-04-29T20:11:48Z")
Using a 9V battery through the barrel jack and the Arduino ide and tells me “Module failed to respond. Please check wiring”. what wires would i need to change ? ---
**Author:** ![YellowDog](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/yellowdog/32/1782_2.png) [@YellowDog](https://community.sparkfun.com/u/YellowDog)\ **Post date:** [April 29, 2025, 9:05pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/8 "2025-04-29T21:05:56Z")
> [@Will\_Jarmer](#): > > Using a 9V battery through the barrel jack 9 volt battery is not capable of providing enough current to operate the RFID reader. You will need a power source that can supply at least 1 amp of current but more current is better. ---
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [April 29, 2025, 9:52pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/9 "2025-04-29T21:52:52Z")
would a barrel jacket that can plug into the wall work ? ---
**Author:** ![TS-Russell](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/ts-russell/32/6092_2.png) [@TS-Russell](https://community.sparkfun.com/u/TS-Russell)\ **Post date:** [April 29, 2025, 10:02pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/10 "2025-04-29T22:02:21Z")
Yes, a barrel jack works…preferably it’d be a mean-well supply. Like he said, 1a is good but 2a or more is even better. That 1st link I sent covers this in in ‘power supply considerations’ section ---
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [May 2, 2025, 1:15am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/11 "2025-05-02T01:15:13Z")
i am having trouble with using an external power source. when i am plugged into computer the tag reader works fine. however once unplugged and external power is used my displays shows "RFID init fail ". ---
**Author:** ![TS-Russell](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/ts-russell/32/6092_2.png) [@TS-Russell](https://community.sparkfun.com/u/TS-Russell)\ **Post date:** [May 2, 2025, 1:44am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/12 "2025-05-02T01:44:19Z")
Share a photo or two of the setup with external power ---
**Author:** ![Will\_Jarmer](https://avatars.discourse-cdn.com/v4/letter/w/ce73a5/32.png) [@Will\_Jarmer](https://community.sparkfun.com/u/Will_Jarmer)\ **Post date:** [May 2, 2025, 5:28pm UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/13 "2025-05-02T17:28:20Z")
![IMG_8139](https://canada1.discourse-cdn.com/sparkfun/original/2X/9/907fef56f631365c0ee707ec0c9d35e2fc3c4eb0.jpeg) ![IMG_8141](https://canada1.discourse-cdn.com/sparkfun/original/2X/5/5c70da989173205d911bfbfdd88a9f5b82b19c56.jpeg) ![IMG_8142](https://canada1.discourse-cdn.com/sparkfun/original/2X/0/090884188f5f564f3d01dbf6b7dd8291652afe40.jpeg) ![IMG_8143](https://canada1.discourse-cdn.com/sparkfun/original/2X/e/e0365b94a1649e2b7553134a8f8169f5a87d3f66.jpeg) the Photo that shows scanning is when it is connected to laptop , all other is on external power ---
**Author:** ![TS-Russell](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/ts-russell/32/6092_2.png) [@TS-Russell](https://community.sparkfun.com/u/TS-Russell)\ **Post date:** [May 3, 2025, 2:06am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/14 "2025-05-03T02:06:06Z")
The soldering looks good; I’d make sure the alligator clips aren’t an issue and probably remove the screen wiring for now to simplify things for testing On the Uno side it looks like the wires might be off by 2 spaces; ![image](https://canada1.discourse-cdn.com/sparkfun/original/2X/4/4301c445c3d1d3648a9b65413d4d399d9ab974f4.png) I’d try moving those 2 yellow fellas over ---
**Author:** ![paulvha](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@paulvha](https://community.sparkfun.com/u/paulvha)\ **Post date:** [May 3, 2025, 7:55am UTC](https://community.sparkfun.com/t/rfid-reader-hookup-problems-with-redboard/64755/15 "2025-05-03T07:55:38Z")
it is a bit hard to see, so I better ask: I see the power led on M7E clearly when connected to the PC (and scanning), but I do not clearly see the power led on the M7E in the pictures with the external power supply. As you apply the external power to VIN, the UNO R3 will switch off the 5V from USB. Maybe that causes a spike that the M7E does not like. Try to remove and reconnect the power to the m7E / breadboard after you apply the external power supply. Is the M7E very hot ? In that case it might just shutdown and you have to wait until it cooled down.