Morning,
If this is the wrong board. Let me know I I will post it some other place. I had a couple XPR6580 sitting around. I tuned my MMDVM to 902.65 and 927.65. My antennas have a flat match. Was not able to get very far away from the MMDVM before I lost the signal. So I hooked my spectrum up to the MMDVM. on 420 it is putting out 14mW. on 900 it is only putting out 818pW. Is this normal? Are there components that needs to be changed on the board to make it work on 900? It says the chip will work from 896 to 950ish. If it is not possible to get more power out of it. I can just get a different MMDVM and run HT's instead. But I would rather run the MMDVM. They are better on power then an HT is.
Thanks,
Ryan (KB8PMY)
MMDVM_HS Duplex 900Mhz
Re: MMDVM_HS Duplex 900Mhz
Can you give some more information about the HAT that you're using please.
It's probably based on the ADF7021 chip for the RF side but it's possible it's something else.
If it is that chip then the Tx output and Rx input match will require component changes but I don't have any values to hand, you might find the data sheet tells you more. A reduction of 70-80dB on the Tx undoubtedly tells me that the output network is not working at the frequency you want but I would also caution you if the antennas are really well matched over a >2:1 frequency range, they may be quite inefficient if that is the case.
HTH
It's probably based on the ADF7021 chip for the RF side but it's possible it's something else.
If it is that chip then the Tx output and Rx input match will require component changes but I don't have any values to hand, you might find the data sheet tells you more. A reduction of 70-80dB on the Tx undoubtedly tells me that the output network is not working at the frequency you want but I would also caution you if the antennas are really well matched over a >2:1 frequency range, they may be quite inefficient if that is the case.
HTH
--
Brian G8SEZ
Brian G8SEZ