I have read that the MMDVM Pi output is 10mW at 100% output. I do not know if this is true.
What I am thinking of doing is attaching different antennas to the Pi and seeing if range can be a factor in using my Anytone H/T while walking about my area. Antennas like the Diamond SRH805S antenna, along with the Sharman flexible antenna and a 70cms ground plane antenna. Want to see if range can play a part in squeezing out more afar contacts as I live in SW Scotland on the Southern Upland Way walk. This a hill area (141m ASL) so would like to see if I can cover my area mostly with the MMDVM and some antenna to have when out and about without using a X30 antenna.
So is the 10mW an actual power output or is is it more? Also do you think I could cover my area with the Pi hat with just a ground plane antenna or the others described?
TX output
Re: TX output
Remember in UK hotspots are permissable without the need for additional licensing as they are intended to cover your property (station) if you are looking to cover a wider area, you might need application for a NOV.
I'd double check the regs if your thinking of having it cover a wider locale.
Sent via smoke signals from my SM-G935F M1DNS (Admin)
I'd double check the regs if your thinking of having it cover a wider locale.
Sent via smoke signals from my SM-G935F M1DNS (Admin)
Andrew M1DNS.
Pi-star Admin Team.
Pi-star Admin Team.
Re: TX output
According to the datasheet the maximum output-power of an ADF7021 (mostly used in hotspots) is 13dBm.
Looking at the signal of this device, I would not recommend to connect it to an outdoor antenna or an power-amplifier without additional filtering means.
Wolfgang, DF1KZ
Looking at the signal of this device, I would not recommend to connect it to an outdoor antenna or an power-amplifier without additional filtering means.
Wolfgang, DF1KZ
Re: TX output
I have three “hotspots”, two are MMDVM boards and the other is a 2m DVAP dongle.
They all produce between 10 and 12mW output, as measured with a Rigol spectrum analyser and attenuator. This is the specification of the IC used in the boards.
The maximum range I can “ping” one of the 70 cm MMDVM units is between 200 and 300 metres across a housing estate. The terrain is flat with few houses. The hotspot is located indoors near a large window favouring the direction of the test, it is around 1.5 metres above outside ground level and the handheld is an Icom ID51 plus 2, which gives a measured 80mW (SLO power setting). The hotspot has a 70mm long helical mounted on the SMA socket and the handheld uses the stock antenna (FA-S270C).
I think that range is pretty impressive and more than enough to cover a typical house and all but the largest garden, even without resorting to an outside antenna, or mounting the hotspot on an upper floor.
73 Dave
They all produce between 10 and 12mW output, as measured with a Rigol spectrum analyser and attenuator. This is the specification of the IC used in the boards.
The maximum range I can “ping” one of the 70 cm MMDVM units is between 200 and 300 metres across a housing estate. The terrain is flat with few houses. The hotspot is located indoors near a large window favouring the direction of the test, it is around 1.5 metres above outside ground level and the handheld is an Icom ID51 plus 2, which gives a measured 80mW (SLO power setting). The hotspot has a 70mm long helical mounted on the SMA socket and the handheld uses the stock antenna (FA-S270C).
I think that range is pretty impressive and more than enough to cover a typical house and all but the largest garden, even without resorting to an outside antenna, or mounting the hotspot on an upper floor.
73 Dave
ID51E plus 2
ID5100E
IC9700
AnyTone AT-D878UV
Chinese MMDVM with OLED on a Pi 3B
DVAP on a Pi 3B
ID5100E
IC9700
AnyTone AT-D878UV
Chinese MMDVM with OLED on a Pi 3B
DVAP on a Pi 3B
Re: TX output
You really are on a hiding to nothing looking to extend the range of a 10mW hotspot past a couple of hundred meters.
A better option would be to use a GD-77 hand held as a 3 or 4 watt wide area MMDVM node/ hotspot/ gateway running in to an external antenna which would give you a more selective Rx and a bit more Tx power. 10km range is possible doing this.
Running a commercial mobile radio as a personal node would give a bit more power, otherwise consider putting up a MMDVM Pi-Star repeater to give coverage up the A76 from Cumnock to Thornhill.
It could be an interesting project
Allister
A better option would be to use a GD-77 hand held as a 3 or 4 watt wide area MMDVM node/ hotspot/ gateway running in to an external antenna which would give you a more selective Rx and a bit more Tx power. 10km range is possible doing this.
Running a commercial mobile radio as a personal node would give a bit more power, otherwise consider putting up a MMDVM Pi-Star repeater to give coverage up the A76 from Cumnock to Thornhill.
It could be an interesting project
Allister