Help with Antenna

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snifftheglove
Posts: 11
Joined: Mon Jan 01, 2018 10:32 pm

Help with Antenna

Post by snifftheglove » Thu Jan 18, 2018 12:07 am

Hi,

Been a few days of playing with the V3 but a little disapointed mostly at my ability :-)

When I got the V3 from the UK Supplier I also got a small telescopic antenna.

I can only pick up 2 radio stations with the V3, these being the 2 local radio stations approx 10miles away. These are on FM. I can not pick up any other stations on FM (now my little pocket radio can pick up lots) and nothing on AM (moving to Q branch). So I am doing something wrong here but what?

I looked on the net for a cheap antenna solution for AM, so I got an SMA-BNC connector and put a long piece of wire on it and strung it up from on side of the room to the other (12 foot) but I was hoping for some AM stations to appear but I could just barley pick up a single one and then with so much static you can barley hear the voice talking. So I tried a T Antenna for FM and still can onlky get the 2 local stations though with better clarity but no others, even no spikes where I could say there might be something.

So where am I going wrong?

tim_rtd
Posts: 144
Joined: Fri Jun 30, 2017 11:34 am

Re: Help with Antenna

Post by tim_rtd » Thu Jan 18, 2018 1:10 am

An antenna of about 15 inch should be good enough to pick up FM broadcast stations. It sounds like you need to bump up the RF gain on your dongle popup where your selecting sampling rate , ppm, etc......different than audio gain.

Even with V3 in direct sampling mode to get down to the HF and AM bands the sensitivity is not great. A much better antenna is needed... Many of us use an upconverter then put the dongle back into quadrature mode resulting in much better reception down there.

snifftheglove
Posts: 11
Joined: Mon Jan 01, 2018 10:32 pm

Re: Help with Antenna

Post by snifftheglove » Thu Jan 18, 2018 1:03 pm

Thanks Tim,

I put a solid 15in copper core stripped of all insulation onto the BNC connector and it has improved reception and able to pick up a few more remote stations (with some interference) but messing with gain helps. Also this antenna is on my desk so expect it will work better once outside, I just have to get some long coax to do this.

On the AM front getting an up-converter would help, but what type/size of antenna would work for AM, again I suspect once it goes outside the reception will be better.

My end goal is to not use the found stations to listen to but to skip through. I am building a Spirit Box or Ghost Box using an SDR. There are custom made spirit boxes but they cost $xxx and I am hoping to use the sdr and a very cheap alternative (because I am not a rich person). I am writing some software that will interact with SDR# via the Remote Network plugin. My software will send SD+ a serious of frequencies to jump to and then skip onto the next frequency using a selectable delay.

A Spirit Box is described here
https://www.ghoststop.com/Spirit-Box-B- ... p-psb7.htm

tim_rtd
Posts: 144
Joined: Fri Jun 30, 2017 11:34 am

Re: Help with Antenna

Post by tim_rtd » Thu Jan 18, 2018 7:45 pm

If your not transmitting, the length of the antenna is kind of moot. A 15ft long piece of insulated wire would be fine.

rtlsdrblog
Site Admin
Posts: 2699
Joined: Mon Nov 19, 2012 11:54 pm

Re: Help with Antenna

Post by rtlsdrblog » Thu Jan 18, 2018 11:11 pm

Make sure that the gain is adjusted manually (turn of all AGCs), and that the antenna isn't obstructed. If you're using it inside behind many thick walls or metal roof then it might be an issue and in that case you should try to get the antenna outside.

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