Re: SAW Filter limitations


"Michael E Fox - N6MEF" <n6mef@...>
 

Also, I’m an “appliance operator” so I don’t understand the purpose of the
filter. But I wonder why the radio would have a limitation that other
amateur radios in the 440 band don’t have. Is this limitation necessary?



Our existing 440 radios are supplemented with cavity filters at sites where
that is needed, just like any radio would be expected to have. One site, in
particular, will probably require the two port version so an isolator can
also be used, just like any repeater would be expected to use. This is
required regardless of how well the radio rejects out-of-band stuff because
we must operate near (physically and frequency-wise) other amateur radios.



Michael

N6MEF





In Northern California, packet and other data activity is in the 433, 434
and 438 range, with wideband channels in the upper of those two ranges.
This is where we would intend to use the device.

http://ncpa.n0ary.org/ncpabandplan.html

Michael

N6MEF



From: UniversalDigitalRadio@...
[mailto:UniversalDigitalRadio@...] On Behalf Of
bhhoyer@...
Sent: Monday, March 17, 2014 10:27 AM
To: UniversalDigitalRadio@...
Subject: Re: [UniversalDigitalRadio] SAW Filter limitations



We could do a UDRX-430.

there is a 20MHz 431 Filter (421-441). Takes care of the bottom of the US
Band as well

It's in a different package (of course) so we'd end up building 440s in
mass then reworking the filters.

Might be a small upcharge of 20-25 USD

Bryan K7UDR

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