OpenGD77

I had no opinion for extended UHF frequency range. But I do not recommend to extend VHF frequency down to 12xMHz for following reason.

1:The civilian aeronautics use 118-137MHz in AM. Since the RDA1846 does not support AM at all,it would be meaningless to use RDA1846 to receive 12x-137MHz.

2:Support TX in 12x-137MHz in FM would be meaningless,and might cause harmful interference to civilian aeronautics.

I recommend the author could reserve extended frequency in source code,but restrict to within 136-174MHz in binary F/W to prevent unintentional abuse.

cmwang wrote: ↑

Sun Apr 19, 2020 6:01 am

I recommend the author could reserve extended frequency in source code,but restrict to within 136-174MHz in binary F/W to prevent unintentional abuse.

The official firmware already does this range, if you change the band limits in the codeplug. Most people already did this.

F1RMB wrote: ↑

Sat Apr 18, 2020 2:54 pm

IU4LEG wrote: ↑

Sat Apr 18, 2020 2:34 pm

It was also implemented the microphone gain for the FM?

Yes.

Cheers.
---
Daniel

I also tried the microphone gain in FM. works well
thanks

Hi,

IU4LEG wrote: ↑

Sun Apr 19, 2020 8:59 am

F1RMB wrote: ↑

Sat Apr 18, 2020 2:54 pm

IU4LEG wrote: ↑

Sat Apr 18, 2020 2:34 pm

It was also implemented the microphone gain for the FM?

Yes.

Cheers.
---
Daniel

I also tried the microphone gain in FM. works well
thanks

Cool


Cheers.
---
Daniel

jobdone wrote: ↑

Sun Apr 19, 2020 9:49 am

tx on 190 made my freq counter show 380 (second harmonic)
tx on 280 made my freq counter show 560 (second harmonic)

There is no RF stage for the range from 174 - 400Mhz, but I found it was better to enable the UHF PA and the UHF Rx amp, because if I use the VHF RF sections for this range, the Rx sensitivity is low.

Its not possible with the way the firmware is written to use a different RF section for the Rx to the Tx.
And the change to make the best use of the baseband RF chip are intended for Rx.

Radio #1:

127 - 178
190 - 282
380 - 564

HI.MY BAOFEN DM-1801 IN TX WORK:

136000 to 172000 - vhf
381000 to 500000 - uhf


does not work at 200 mhz, is this so? Can someone make it work in that band correctly?
73

Hi,

CX2JO wrote: ↑

Mon Apr 20, 2020 1:21 pm

HI.MY BAOFEN DM-1801 IN TX WORK:

136000 to 172000 - vhf
381000 to 500000 - uhf


does not work at 200 mhz, is this so? Can someone make it work in that band correctly?
73

Did you turned "Band Limits" off, in the Options ?

Cheers.
---
Daniel

Hi,
If I verify that exactly, then I have another one that in uhf I cannot achieve that transmits in hotspot mode in uhf, I don't know if this problem has happened to someone. Do you say that in the 200mhz band in rx and tx it has the same range? and what power does it offer?
thanks

F1RMB wrote: ↑

Mon Apr 20, 2020 1:35 pm

CX2JO wrote: ↑

Mon Apr 20, 2020 1:21 pm

HI.MY BAOFEN DM-1801 IN TX WORK:

136000 to 172000 - vhf
381000 to 500000 - uhf


does not work at 200 mhz, is this so? Can someone make it work in that band correctly?
73

Did you turned "Band Limits" off, in the Options ?

Cheers.
---
Daniel

It has installed the last fw dated 04/18/20 where the frequency expansion is, as it is in beta, I am interested in trying and seeing what errors can be corrected.
73 javier

CX2JO wrote: ↑

Mon Apr 20, 2020 1:54 pm

Hi,
If I verify that exactly, then I have another one that in uhf I cannot achieve that transmits in hotspot mode in uhf, I don't know if this problem has happened to someone. Do you say that in the 200mhz band in rx and tx it has the same range? and what power does it offer?
thanks

F1RMB wrote: ↑

Mon Apr 20, 2020 1:35 pm

CX2JO wrote: ↑

Mon Apr 20, 2020 1:21 pm

HI.MY BAOFEN DM-1801 IN TX WORK:

136000 to 172000 - vhf
381000 to 500000 - uhf


does not work at 200 mhz, is this so? Can someone make it work in that band correctly?
73

Did you turned "Band Limits" off, in the Options ?

Cheers.
---
Daniel