# Nagoya NA-773 Whip Wide-Band Mod for SDR

**URL:** <https://www.ruby-forum.com/t/nagoya-na-773-whip-wide-band-mod-for-sdr/229980>\
**Category:** GNU Radio\
**Created:** [May 25, 2014, 3:33am UTC](https://www.ruby-forum.com/t/nagoya-na-773-whip-wide-band-mod-for-sdr/229980 "2014-05-25T03:33:31Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jason\_sam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/7993a0/32.png) [@jason\_sam](https://www.ruby-forum.com/u/jason_sam)\
**Post date:** [May 25, 2014, 3:33am UTC](https://www.ruby-forum.com/t/nagoya-na-773-whip-wide-band-mod-for-sdr/229980/1 "2014-05-25T03:33:31Z")

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I have seen a few messages asking about small, cheap antennas to use for  
portable SDRs, considering the RF bandwidths can span two decades. I  
found an SMA female, 12 telescoping whip and made a video showing how to  
remove the loading coil, along with the VSWR obtainable with an  
appropriate counterpoise (i.e. B200 or bladeRF sized PCB). The OEM  
antenna (Nagoya NA-773) is very inexpensive and easy to mod with basic  
dremel and soldering skills. VSWR of 3:1 is obtainable from 200 MHz  
through 6 GHz, with the exception of 1.8 - 2.2 GHz. Ill probably do a  
follow-up experiment to see if tuning can be done by receiving via a  
small, non-resnoant loop on the adjacent RX port.

[![](https://img.youtube.com/vi/EFlhSkqZ9dE/maxresdefault.jpg "Nagoya NA-773 Whip Wide-Band Mod for SDR") ](https://www.youtube.com/watch?v=EFlhSkqZ9dE)

Lou  
KD4HSO