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RSSI .DAT works?
Posted: Sun Feb 16, 2020 3:36 pm
by IK8JHL
I wanted to know if OpenGD77 supports RSSI.dat and if there is a way to calibrate it. I tried to launch pistar-mmdvmcal but it doesn't support OpenGD77
Re: RSSI .DAT works?
Posted: Sun Feb 16, 2020 8:20 pm
by VK3KYY
MMDVMCAL is not supported as there is no need for this to calibrate the radio.
The RSSI value is taken directly from the AT1846 RF IC, however the chip is not super accurate
Re: RSSI .DAT works?
Posted: Mon Feb 17, 2020 11:55 am
by IK8JHL
VK3KYY wrote: ↑Sun Feb 16, 2020 8:20 pm
MMDVMCAL is not supported as there is no need for this to calibrate the radio.
The RSSI value is taken directly from the AT1846 RF IC, however the chip is not super accurate
So if I understand correctly, mmdvmhost doesn't use the rssi.dat file? Is the value I read in the Pi-star dashboard read directly from the GD-77?
Re: RSSI .DAT works?
Posted: Mon Feb 17, 2020 1:41 pm
by F1RMB
Hi,
IK8JHL wrote: ↑Mon Feb 17, 2020 11:55 am
VK3KYY wrote: ↑Sun Feb 16, 2020 8:20 pm
MMDVMCAL is not supported as there is no need for this to calibrate the radio.
The RSSI value is taken directly from the AT1846 RF IC, however the chip is not super accurate
So if I understand correctly, mmdvmhost doesn't use the rssi.dat file? Is the value I read in the Pi-star dashboard read directly from the GD-77?
The default Pi-Star mapping file (RSSI.dat) just convert positive to negative RSSI values:
Code: Select all
# RSSI Default Values for MMDVM_HS
#
43 -43
53 -53
63 -63
73 -73
83 -83
93 -93
99 -99
105 -105
111 -111
117 -117
123 -123
129 -129
135 -135
141 -141
So, what you see in the Pi-Star (or a dashboard) it's the value reported by the GD itself, but switched from positive to negative by MMDVMHost, using the RSSI.dat file:
Code: Select all
M: 2020-02-17 13:41:55.221 DMR Slot 2, received RF voice header from F1RMB to 9990
M: 2020-02-17 13:42:01.156 DMR Slot 2, received RF end of voice transmission from F1RMB to 9990, 5.8 seconds, BER: 0.5%, RSSI: -70/-43/-69 dBm
Cheers.
---
Daniel
Re: RSSI .DAT works?
Posted: Mon Feb 17, 2020 2:05 pm
by IK8JHL
OK, so the ratio is 1: 1 and there is no need calibration (about) but it only eliminates "negative", thanks for the answers