MMDVM DUAL HS Hat with external Amplifiere

MMDVM_HS Hat hardware
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DL8MMR
Posts: 5
Joined: Sun Jun 24, 2018 1:25 pm
Location: Germany

MMDVM DUAL HS Hat with external Amplifiere

Post by DL8MMR » Sat Apr 13, 2019 5:50 am

Hello,

i'm using a original DB9MAT board with the current Firmeware 1.4.16. At my Board is describe one SMA TX output and one SMA RX input. So i'was think
this is FIX TX & RX SMA Connectors. But if connect on TX, some Amplifiere the Board recieve nothing more. The RX SMA Connector is still connected to some Diamond X30N Antenna.

My Question, is there some configuration way, to fix TX is relay the TX sma connector and RX connector is fix RX???

Thanks for Help!
73 DL8MMR

M1DNS
Posts: 274
Joined: Thu Apr 05, 2018 5:30 am

Re: MMDVM DUAL HS Hat with external Amplifiere

Post by M1DNS » Sat Apr 13, 2019 7:44 am

Unless you employ a duplexer that tx power would be overloading the Rx input. It's not recommended to attach an amp to a hotspot board as a driver there's very little filtering employed on the boards. Ur prob spewing junk all over the bands.

If you need a wide area install go for an mmdvm radio board and a couple Tait 8000 series or GM 300 series mobile radios, and base the build around that.

Andrew M1DNS, (Mod)



Andrew M1DNS.
Pi-star Admin Team.

DL8MMR
Posts: 5
Joined: Sun Jun 24, 2018 1:25 pm
Location: Germany

Re: MMDVM DUAL HS Hat with external Amplifiere

Post by DL8MMR » Sat Apr 13, 2019 8:49 am

> Ur prob spewing junk all over the bands

I'know i'want test only - but is there a way in the configuration to fix dmr and c4fm to rx and tx connector?

M1DNS
Posts: 274
Joined: Thu Apr 05, 2018 5:30 am

Re: MMDVM DUAL HS Hat with external Amplifiere

Post by M1DNS » Sat Apr 13, 2019 10:05 am

No. Not as it is...
The dual refers to the hardware. consisting of two 7021 radio chips.
ones running as the TX. The other as the Rx.

They are set up in the STM chip.

whether that could be changed in the STM firmware I'm not sure ??
but not something that can be done within pistar.

It'll need firmware rewrites from the MMDVM group, If at all possible.

Andrew M1DNS, (Mod)

Andrew M1DNS.
Pi-star Admin Team.

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