On 01/29/2019 03:16 PM, Albin Stigö wrote:
Loss will be proportional to the length of coax, type of coax,
impedenace match and frequency. Higher frequency, higher loss. For
example at 10MHz the loss in in 100m RG58 would be around 3.7dB, at
1000MHz 48dB, a factor 27000 difference.
It's normally best practice to put the receiver/transmitter as close
to the antenna as possible.
--Albin
That's quite true, however the higher and more in the clear outdoors you
can put it will improve the signal considerably. For coax, you should
use a 50 ohm cable, preferably the Times Microwave
types LMR-240 or, better, LMR-400. You can look up the specs on these
cables on the Internet and calculate cable loss versus length from the
information found there. You will need to adapt the
cable connectors to the small ones on your radio. Commercial adapters
are available for all combinations of interface. I suggest terminating
either of the cables I recommend in type N male.
Doug, WA2SAY, retired RF Engineer
On Tue, Jan 29, 2019, 21:07 Tarquin <tarquin.ro...@gmail.com
<mailto:tarquin.ro...@gmail.com> wrote:
Hi
If you want to go "cheap" use coax intended for satellite TV
reception. Be carefull about 75ohm, as the Hack RF is a 50 ohm
system, you can use RG58U not to costly, don't expect good
performance above 1.2 GHz. Not sure what you want to intercept, if
it VHF UHF you will be ok, else you could try RG213 but that ½
inch thich and you will have to adapt.
The thinner coax RG179 /178 will be fairly lossy.
I suggest personaly start with RG58 its cost effective and maybe
an LNA near the antenna
Regards
Zr1tR
*From:*Discuss-gnuradio
[mailto:discuss-gnuradio-bounces+tarquin.roode
<mailto:discuss-gnuradio-bounces%2Btarquin.roode>=gmail....@gnu.org
<mailto:gmail....@gnu.org>]
*On Behalf Of *david vanhorn
*Sent:* Tuesday, January 29, 2019 9:52 PM
*To:* cliff palmer
*Cc:* Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org>
*Subject:* Re: [Discuss-gnuradio] Moving my antenna
Coax loss can be a big issue.
Given the low power levels you will suffer less loss on a long run
using 75 ohm coax cable which is designed for low loss, even
assuming you do nothing about the mismatch at the ends of the
run. All that is good up to about 1ghz where more specialized
coax is needed for minimum loss.
The antenna is a significant part of the equation and you are well
advised to use an antenna suited for the frequency of interest.
Broadband antennas like discones have very low gain, and they pull
in other strong signals you don't want.
On Tue, Jan 29, 2019, 12:40 PM cliff palmer <palmercl...@gmail.com
<mailto:palmercl...@gmail.com> wrote:
I have a HackrfOne with an Ant500 antenna connected to my
workstation in my basement (where the internet connection
lives). I need to move the antenna out of the basement to
improve reception, so I thought I would use coax to connect
the antenna from upstairs to the HackrfOne.
I'm too new to SDR to be confident about just moving the
antenna and using a spare length of cable coax. Please
provide some help on selecting, sizing and connecting coax
between the HackrfOne and the Ant500.
Thanks
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org>
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient>
Virus-free. www.avg.com
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient>
<#m_-7042655357582419932_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org>
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
