Amazing.
Actually on DMR, its not really a problem, because its only 50% duty cycle.
Nice to read that fixed the problem on your side.kd2lh wrote: ↑Tue Feb 25, 2020 2:38 pmRunning all night, no problems with dumping out of hotspot mode.
I think we should close this problem, and recognize that the RF can get into the USB cable supplied by Radioddity with the radio (that we use to interconnect the RPi and the GD77.
Documentation should be added to recommend installation of one or two ferrite filters on the USB and power feeds to the RPi, and that the RPi operate in a metal enclosure if it's in the proximity of the radio. Keep cabling 90 Degrees to the radiation plane of the antenna used.
- - - - - - -
Separately, it's good to see the GD77 used on DMR at full 5 watt power in hotspot mode. Since the Radioddity development lab in China has not responded about power dissipation and continuous duty cycle use of the radio, experimentation like this is the best we'll have.
Recently surfaced documentation of the final amplifier (posted on this site) has also been helpful.
RF Power LDMOS Transistor
High Ruggedness N--Channel
Enhancement--Mode Lateral MOSFET
Freescale Semiconductor Type: AFT05MS004NT1
viewtopic.php?f=13&t=609&p=5256&hilit=aft05%2A#p5256
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usb usb1-port1: disabled by hub (EMI?), re-enabling...
[44282.786486] usb 1-1: USB disconnect, device number 2
[44282.786891] cdc_acm 1-1:1.0: failed to set dtr/rts
[44282.986352] Indeed it is in host mode hprt0 = 00021d01
[44283.266178] usb 1-1: new full-speed USB device number 3 using dwc_otg