[arm-allstar] Interesting info on the new hamvoip lowpass filter

[Harry Romano]

Doug ,

How are you? I tried to login on the philadelphia hub and i hear that im connected but i don't hear any one an no one hears me any idea why.I am using your 1.5 code same as alway and have not changed anything here. problem is with node 28796. 433.100 repeater.

73

Harry KC4RPP
cell 239-200-4919 can you call me please.

-----Original Message-----
>From: "\"Doug Crompton via arm-allstar\"" <arm-allstar at hamvoip.org>
>Sent: Jun 25, 2018 1:09 AM
>To: ARM Allstar <arm-allstar at hamvoip.org>
>Cc: Doug Crompton <wa3dsp at gmail.com>
>Subject: [arm-allstar] Interesting info on the new hamvoip lowpass filter
>
>This was mentioned before but not to any great detail. If you are using the
>hamvoip V1.5 image v1.5.3-32 5/28/2018 or later your image has the new
>brick-wall low-pass filter. The low-pass filter has a corner frequency at
>3.5KHz, with all components at least -50dB down at 4KHz and above. This
>filter is always on and adds the most fidelity that you can get at an 8Khz
>sample rate.
>
>Here is an image of the new Low Pass filter:
>https://hamvoip.org/docs/FIR-LP-simpleusb-2018-05-27-1.png
>
>This filter eliminates the need for any hardware filtering in FOBS so the
>"fancier" FOB's with hardware low-pass filtering like the DMK-URI and
>others are not needed to achieve this well filtered and excellent audio.
>Using this software and the filter means you no longer have to worry about
>out of band audio components when using the cheaper FOB's without any
>hardware low-pass filtering.
>
>
>*73 Doug*
>
>*WA3DSP*
>
>*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*
>_______________________________________________
>
>arm-allstar mailing list
>arm-allstar at hamvoip.org
>http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
>Visit the BBB and RPi2/3 web page - http://hamvoip.org