Search found 936 matches
- Tue May 07, 2024 2:54 pm
- Forum: GD-77 / DM-1801 / RD-5R / GD-77S
- Topic: RD-5R Power Calibration
- Replies: 7
- Views: 458
Re: RD-5R Power Calibration
It's probably accurate enough. Power measurements are difficult to do accurately and also not really very important so I wouldn't worry too much about them. It sounds like the minimum your radio can output is 0.28W and the slope is probably not flat below 1W . The firmware power settings below 1W ar...
- Tue May 07, 2024 8:46 am
- Forum: GD-77 / DM-1801 / RD-5R / GD-77S
- Topic: RD-5R Power Calibration
- Replies: 7
- Views: 458
Re: RD-5R Power Calibration
It may be that your radio cannot go lower than 1W. Individual radios vary greatly so that is a possibility. You can check by going to the 1W Calibration and reducing the adjust level to zero. That is the lowest power that can be achieved. Also to calibrate correctly you should do at least three adja...
- Fri May 03, 2024 4:38 pm
- Forum: General discussions
- Topic: RD-5R won't talk to hotspot, what have I done wrong?
- Replies: 7
- Views: 407
Re: RD-5R won't talk to hotspot, what have I done wrong?
Those sort of frequency errors are not unusual and a proper DMR repeater would have no problem with them. Unfortunately most Hotspots use a receiver chip that is not really designed for TDMA and consequently is very critical on frequency. The SDR play doesn't have a very accurate frequency reference...
- Wed May 01, 2024 8:47 pm
- Forum: General discussions
- Topic: RD-5R won't talk to hotspot, what have I done wrong?
- Replies: 7
- Views: 407
Re: RD-5R won't talk to hotspot, what have I done wrong?
It may be that your two radios are on very slightly different frequencies. Most hotspots are excessively fussy about frequency. Do you have a means of comparing the transmit frequency of the two radios? A radio or SDR with a spectrum display would show the difference. You could then use the OpenGD77...
- Sun Apr 28, 2024 9:40 pm
- Forum: Off topic
- Topic: Modification of the Radioditty charger with "TP5100" card at $ 2.
- Replies: 81
- Views: 81930
Re: Modification of the Radioditty charger with "TP5100" card at $ 2.
I don't think so. The charging voltage is defined internally in the chip.
Colin G4EML
Colin G4EML
- Sun Apr 28, 2024 9:32 pm
- Forum: General discussions
- Topic: Simplex repeater possible?
- Replies: 7
- Views: 3412
Re: Simplex repeater possible?
The reason the two handhelds can't hear each other is because they are both set for DCDM TS Split mode. They transmit on the selected timeslot but receive on the other one. Hence when set to transmit on TS2 they are actually receiving on TS1. As the guy says this SFR implementation is specific to An...
- Fri Apr 26, 2024 2:35 pm
- Forum: General discussions
- Topic: Simplex repeater possible?
- Replies: 7
- Views: 3412
Re: Simplex repeater possible?
Yes, it is called Single Frequency Repeat and is available on high end DMR radios from the likes of Motorola and Hytera. As Daniel says it also needs DCDM support on the handhelds to differentiate the timeslots. It doesn't need a duplexer as it is single frequency. However it does need radio hardwar...
- Thu Apr 25, 2024 10:40 pm
- Forum: Baofeng DM-1701 / Retevis RT-84 specific
- Topic: DM-1701 - Shouldn't it show up as a serial port"
- Replies: 2
- Views: 3454
Re: DM-1701 - Shouldn't it show up as a serial port"
You are correct.
The original firmware does not enumerate as a com port.
OpenGD77 does enumerate as a com port in normal use.
Both radios enumerate as an STM DFU device when set to download firmware. (This is defined in the radios bootloader which remains untouched by OpenGD77. )
Colin G4EML
The original firmware does not enumerate as a com port.
OpenGD77 does enumerate as a com port in normal use.
Both radios enumerate as an STM DFU device when set to download firmware. (This is defined in the radios bootloader which remains untouched by OpenGD77. )
Colin G4EML
- Thu Apr 11, 2024 9:55 pm
- Forum: TYT MD-UV380/390 / UV380/390 Plus 10W / Retevis RT-3S / Baofeng DM-1701 / DM-1701B / Retevis RT-84
- Topic: UV380 + DM-1701 Beta 2023 03 08
- Replies: 12
- Views: 4539
Re: UV380 + DM-1701 Beta 2023 03 08
Yes, as mentioned before we know the the radio can do DCDM but we don't know how to do it! As Roger said, DCDM seems to be a vendor specific feature and as such is not well documented in the ETSI DMR spec. Likewise the limited HRC6000 documentation barely mentions it. It might be possible to generat...
- Wed Apr 10, 2024 8:05 pm
- Forum: TYT MD-UV380/390 / UV380/390 Plus 10W / Retevis RT-3S / Baofeng DM-1701 / DM-1701B / Retevis RT-84
- Topic: Flat audio (9600baud G3RUH) data port from SP/MIC?
- Replies: 4
- Views: 1880
Re: Flat audio (9600baud G3RUH) data port from SP/MIC?
In theory it would be possible to have flat audio option for the radio, at least as far as the actual RF chip is concerned. However there is no control over the additional audio components in the microphone and speaker paths. So the end result may not have a flat response, especially at the low freq...