op 17-03-14 16:50, bhhoyer@... schreef:

 

The UDR has a SAW Filter in both the transmit and receive paths. We are currently using a 440MHz filter with a 19MHz BW, meaning we are 3db down at 430.5MHz and 449.5MHz.

I have been searching for 20MHz filters and have found no reasonable cost solutions. I will be traveling to China later this year to look into the cost (MOQ really) of having SAW filters made to our specification.

Looking at the ARRL BandPlan for 70cm, ATV is up to 432 and the top of the band is for Voice repeaters. Many countries only go up to 440.

The question for the group is, how does this affect your planned deployment? Is it a real issue for production.

Thanks,

Bryan K7UDR

All 9k6 AX.25 channels in the Netherlands are between 430.400 and 431.025 and german duplex ax.25 channels have input between 430.400 and 430.5875 and output between 439.800 and 439.9875.

So there would be some limitation if the 19 MHz SAW filter is used in this configuration.

73 de Andre PE1RDW