FAQ:what MODE you Tested ? DMR or YSF or P25 I tested is the same. FAQ:Does i need test Using MMDVMCal Program?If You Tested Fail,Best way Using MMDVMCal To Test GM3XX TX- Mobile Function. GM3XX RX- Function It is Easy To Check Just COS(RECEIVE SIGNAL) LED And MODE LED,if Both LED ON ,GM3XX Rx is work! FAQ:Does i need to change MMDVM.ini -TX Invent and RX Invent?that is Also Import,in MMDVMCal TX Testing Mode you can Press I to Invent TX to Ensure Your GM3xx is invent or not . TESTED:GM950i TX Invent =0,RX Invent=0 BEST for Test is GM338 and GM950i ,GM300 TX Freq is not stable ,rx is ok GM300 need set inside Jumper to Disable 300HZ and 3000HZ filter. GM950i need set RX AUDIO(FLAT(UNSQUELCHED)Accy Pin 11,and GP1 PTT LOW 3(I/P) in GP I/O Lines 1.Support 5V microusb Power input(1A) 2.Support OTG Function 3.Support wifi client mode(connect home wifi 4.Running Repeater Mode, example 438.000MHZ -5 5.Cp210x Serial out (115200bps) Debug info BER Login ERROR 6.Easy Configution MMDVM ini File in web 7.Digital Echo (Parrot) Repeater Function (YSF, DMR, P25) 8.Support MD380, MD760, FT2D, XTS3000, XTS5000, MOTO Technical support: jumbospot17.blogspot.com P8268,etc. colour: green Material: ABS size: 65 x 56mm Package Contents: 1 x Repeater Modem Only 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.