Features: 1. Hotspot Board Kit P25 for Pi-star MMDVM Power Bank2. Only for Mini Duplex MMDVM board3. Set up Pi-star software and raspberry hardware (rpi 0-3) New pi4b needs to remove Right Socket4. Pi-star general configuration of MMDVM_DUPLEX5. Set controller mode: duplex repeater or simpleDescription: 1. Radio frequency: Freq: 144-148, 219-225, (main frequency band) 420-475, 842-9502. Duplex mode: Example: RX: 438.000000 TX: 433.0000003. Duplex mode: Example: RX: 145.000000 TX: 433.0000004. Simple mode: Example: RX: 438.000000 TX: 438.0000005. Radio/Modem Type: STM32-DVM/MMDVM_HS- Hat(GPIO) or any other (GPIO board)6. : (not needed now, some old boards need to be set)7. AdminExpertEdit MMDVMHOSTRXOFFSET=0 TXOFFSET=0 (default value in pistar)8. (Update: 2019/2 new 3225 TCXO so offset is 0)9. Update new firmware: (pi-star / Expert / ssh access / user : pi-star pass: raspberry)10. sudo pistar-mmdvmhshatflash hs_dual_hat11. The default bit error rate is less than 5%, and the default offset is 0. If the bit error rate is 5%, as long as the signal can be received, it can be corrected through offset.Note: Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The Usesize: about 65 x 31 x 15mmMaterial: Aluminum PCBcolour: As ShownPackage Contents: 1 x Hotspot Board Kit (With Case And Screen)2 x Pin Header Socket1 x Oled BoxOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.