Monday, April 16, 2018

UserGuide for MMDVM Repeater Kit Board (LinkerV3)

Repeater Kit Board interface definition (for Nano series) #MMDVM#, using with MOTO GM338/GM300/M120/GM3188, Interface definition reference, other devices follow board interface "PTT/TX/GND/RSSI/COR/RX" .
Compared with Duplex hotSPOT, it can provide larger and more stable power output without the need of TX amplifier.


Has verifying radio list ,
by Nano users:
@BG8FCQ GM950i, setting view the end of this BLOG
@BD7NJC M120  ,same as GM300,
@BD7ILU GM300 , Can not change TCXO,otherwiseTX )to termail radio not work
@BH3PXX GM300 DR-1X FT-7800 C4FM DMR
@BH1RQN GM338 ,need change pi-star config TXInvert=0
@DW4CHZ maxtrac motorola ,two radio are working good without any adjustment on board
@BI7JTA CDM1250/CDM1550/GM338 need to do:
1) Re program radio follow user guide,  
2) Change pi-star config TXInvert=0

MOTOROLA M120/GM300/GM338/CDM1250/GM3188, DMR/YSF/P25/NXDN/DSTAR/POCSAG MODE

Recommend radios for homebrew repeaters (G4KLX)

Step by step:
1) Test simplex first, use 1x radio, when 2x radio can work well in simplex mode, then
2) test duplex with 2 radio + duplexer .
Otherwise, you do not know where is the problem.


Linker V3 define↓

Linker for Motorola radio(Also for other radio)




Act as a simplex hotSPOT



Act as a repeater(Duplex) mode



POCSAG mode support


MOTO GM300 need modify the P551 to A, P601 to B, open the case,

And keep the TCXO factory ,not change it ,otherwise the TX(gm300 to DMR radio can not decode data)↓

The right radio TCXO has been change, will cause terminal radio can not decode digital voice data↓



                                             Linker V3 define↓




Simplex mode(RX and TX in one board) V2↓

Repeater(Duplex) mode (RX and TX split into 2 board) V2



For FT-2720


Test successful with CDM1250(GM338)



GM338/CDM1250
http://mmdvm.io/files/CDM1250_GM338_notes-for-interfacing-the-cdm-1250-uhf-radio-with-the-mmdvm-board.pdf


GM3188 (Change to Engilsh description soon)







Debug RX:(Terminal radio to MMDVM decode)
Purpose:
Adjust your external repeater radio with your MMDVM repeater board
Require:
Yes
See the photo and the short videos at the end segment.

Ensure:
1) Test simplex first, use 1x radio, when 2x radio can work well in simplex mode, then
2) test duplex with 2 radio + duplexer .
Otherwise, you do not know where is the problem.



Debug TX:(MMDVM to Terminal radio decode)
Purpose
Adjust TX ,Radio transmit, terminal device decode if normal.
Require
No, just when your terminal radio not decode digital signal.


SDR spectrum assistant adjustment(Optional) 


Use with POCSAG, firmware RPT_1.4.7




Display interface definition:

OLED: VCC/GND/SCL/SDA (left to right)
Nextion: the STM32F105 not support modem type, just support ttyUSBX,use USB to TTL Adapter,suggest use CP2102 or CH340,
HS RXD to Nextion TX
HS TXD to Nextion RX
HS 5V   to Nextion 5V
HS GND to Nextion GND



Duplexer you can find here,
http://mmdvm.bi7jta.org/2018/06/duplexer-preview-made-by-my-friend.html


Extended reading 

Add whitelist Talkgroup to TS1,TS2 #DMR
http://mmdvm.bi7jta.org/2018/05/mmdvm-uses-experience-and-skills.html

How to buy

Facebook https://www.facebook.com/cqcqcq73/
email to bi7jta@gmail.com

How to flash Pi-Star OS


Download the new version Pi-Star IMG

Add whitelist Talkgroup to TS1,TS2 #DMR

rpi-rw
sudo nano /etc/mmdvmhost
[DMR]
Enable=1
Beacons=0
BeaconInterval=60
BeaconDuration=3
ColorCode=1
SelfOnly=0
EmbeddedLCOnly=0
DumpTAData=1
# Prefixes=234,235
# Slot1TGWhiteList=
# Slot2TGWhiteList=  

Youtube test Video for reference






Useful resource reference,

Some link for reference,

By f5uii
https://www.f5uii.net/en/tuning-mmdvm-dmr-tait-tm8100-tm8115/
By OH1E
https://www.youtube.com/watch?v=zqs4NVBvNHE&t=0s&list=PLe3vAuVeEGj-jYT4lNsAehVkH2FDV2PHo&index=4

Ajuste de desviación en frecuencia en MMDVM, parte 1 (teoría)
https://www.youtube.com/watch?v=-m8CcLH4KiI 

Ajuste de desviación en frecuencia en MMDVM, parte 2 (práctica)
https://www.youtube.com/watch?v=fM3NYKRIak8&t=5s 

Recommend for Motorola radio 
https://wiki.brandmeister.network/index.php/Homebrew/MMDVM 

installation-calibration-adjustment-tunning-mmdvm-mmdvmhost-raspberry-motorola-gm360

https://www.f5uii.net/en/installation-calibration-adjustment-tunning-mmdvm-mmdvmhost-raspberry-motorola-gm360/5/ 

Collection for radio setting

GM950i
Programming radio

Config Pi-Star in Expert mode

 Simplex mode

Duplex(repeater) mode


1 comment:

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