Search found 55 matches

by franko
Mon Jul 15, 2019 12:07 am
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 4275

Re: Evaluating RF filters?

Franko, this is what you need to get rid of MW interference, it is effective and easy & inexpensive to build, just look at the thread. https://www.sdrplay.com/community/viewtopic.php?f=5&t=3973#p12847 Very interesting thread, thanks for the link. It sounds like it was a fun project. My challenge is...
by franko
Sat Jul 13, 2019 9:41 pm
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 4275

Re: Evaluating RF filters?

I am using a home built 2 pole elliptic LP filter with a response very similar to yours. Think the poles are slightly higher in frequency. I'm using it for NDB chasing. There is some noticeable attenuation starting around 500 KHZ. My biggest challenge on the lower bands is the extremely strong MW A...
by franko
Sat Jul 13, 2019 7:13 pm
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 4275

Re: Evaluating RF filters?

Thanks to glovisol for the links and Mike2459 re comments on frequency sweeps. I'll have to check my Siglent. As for attenuation, a while back I invested in a really useful 110 dB rotary attenuator that I use frequently when I want to very gradually introduce a signal into an SDR or similar. For now...
by franko
Sat Jul 13, 2019 1:08 am
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 4275

Re: Evaluating RF filters?

Hi Jim, thanks for the message. I did a search here on "tracking generator" and came up with nine pages of hits. It's sounding as though this will turn into a somewhat more involved project than I originally envisioned. Meanwhile I happened to run across the following post on using a broadband noise...
by franko
Fri Jul 12, 2019 5:40 am
Forum: Spectrum Analysis
Topic: Evaluating RF filters?
Replies: 19
Views: 4275

Evaluating RF filters?

Are there instructions or a tutorial on how to use the spectrum analyzer software with an SDRplay to produce a frequency curve of an RF filter (i.e. low-pass, high-pass, band-reject, etc)? I have some RSPduo's and RSP2's, as well as a nice Siglent waveform generator, but have never used the software...
by franko
Sat Apr 20, 2019 10:44 pm
Forum: SDRuno
Topic: Setting up SDRUno to be controlled by Omni-Rig?
Replies: 2
Views: 1210

Re: Setting up SDRUno to be controlled by Omni-Rig?

Thanks, Andy, that's a huge help. SDRUno (or anything related to SDRplay) isn't on Faros' list of rigs to choose from, but the Kenwood TS-480 is, so I'll go with that. That piece of information alone probably saved me substantial wheel-spinning. Now I just have to reacquaint myself with creating the...
by franko
Sat Apr 20, 2019 8:59 pm
Forum: SDRuno
Topic: Setting up SDRUno to be controlled by Omni-Rig?
Replies: 2
Views: 1210

Setting up SDRUno to be controlled by Omni-Rig?

I'm interested in using Faros 1.4 ( http://www.dxatlas.com/Faros/ ) with an SDRplay RSPduo and SDRUno to monitor NCDXF beacons ( http://www.ncdxf.org/pages/beacons.html ). This involves: -- SDRUno passing audio to Faros via VAC (something I'm very familiar with from working with WSJT-X); and -- usin...
by franko
Sun Feb 10, 2019 9:48 pm
Forum: SDRplay related
Topic: Behavior of AM broadcast images in longwave spectrum?
Replies: 3
Views: 1634

Re: Behavior of AM broadcast images in longwave spectrum?

Thanks very much for the link to the paper. Since the broadcast images do move when the LO changes, that makes it clear that they are higher-order mixing products and not the result of intermodulation. In initial daytime experiments, I've found that by using both the RSPduo's MW notch filter and the...
by franko
Sun Feb 10, 2019 8:03 pm
Forum: SDRplay related
Topic: Behavior of AM broadcast images in longwave spectrum?
Replies: 3
Views: 1634

Behavior of AM broadcast images in longwave spectrum?

I'm scratching my head a little over the behavior that I'm seeing with AM broadcast images in the longwave spectrum, and would be interested in any help or ideas. I have an RSPduo attached to a Wellbrook ALA1530LNP mag loop antenna, controlled by SDRUno 1.24 on a Windows 7 PC. Normally the longwave ...
by franko
Fri Feb 01, 2019 7:19 pm
Forum: SDR Antennas
Topic: Antenna for LW
Replies: 14
Views: 8093

Re: Antenna for LW

Great lightning map website! You mentioned WSPR in your last post. I tried it out last light, heard several hams in Arizona and New Mexico on 630 meters. There was one log entry for K9FD in grid square BL11 (the Hawaiian Islands). In addition to WSPR, it seems as though there's a certain amount of J...