Search found 226 matches

by snn47
Tue Dec 01, 2020 6:06 pm
Forum: Other SDR Devices
Topic: I have a PAL and FM TV tuner card, can I use this as SDR?
Replies: 3
Views: 855

Re: I have a PAL and FM TV tuner card, can I use this as SDR?

Internal and external PAL and FM tuner cards were built to cover the terrestrial analogue and/or DVB BC and TV channels. Those internal cards external boxes consist of a turner and a circuit for converting the signals for the pc. To my knowledge only some of those DVB (?), may be used as SDR, while ...
by snn47
Tue Dec 01, 2020 5:51 pm
Forum: Other SDR Devices
Topic: HackRF One, ADALM-PLUTO comparison, or other possibilities
Replies: 2
Views: 407

Re: HackRF One, ADALM-PLUTO comparison, or other possibilities

There is no simple answer to your question, it depends on the frequency range and bandwidth you want to monitor. The intermodulation free dynamic range (ratio of strong to weak signals received) limits the sensitivity you can achieve. How strong would undesired signals be at your receiver input? Eve...
by snn47
Tue Dec 01, 2020 5:29 pm
Forum: Antennas
Topic: What is the device called that automatically points the antenna toward a satellite as it passes across the sky?
Replies: 2
Views: 426

Re: What is the device called that automatically points the antenna toward a satellite as it passes across the sky?

What dish size and what tracking range do you need, what type of satellite do you want to track in orbit or geostationary? For small dishes used in airplanes and ships they are called Automatic Tracking Satellite Dish. If you look for sate TV you can find two motor driven actuator mounts for steerin...
by snn47
Wed Nov 04, 2020 7:54 pm
Forum: Antennas
Topic: Mini Whip Mod For VLF
Replies: 2
Views: 907

Re: Mini Whip Mod For VLF

Hello Bruce, I am wondering about the benefit of using an isolated BNC connector, because Coax cable and connector are asymetrical systems. Even if the output connector to the receiver is not grounded, the outer shield of the antenna input of any receiver would be grounded, except for battery powere...
by snn47
Wed Nov 04, 2020 7:49 pm
Forum: Troubleshooting Help
Topic: Can a ground loop damage an RTL SDR?
Replies: 1
Views: 601

Re: Can a ground loop damage an RTL SDR?

I try to answer the questions as I understand them. Yes all weird things can happen, or you had lightning strikes somewhere close by and secondary effects effected your AC which can kill some devices, while others survive A power supplies AC-In should be isolated from the AC-out. Some PS AC connecto...
by snn47
Fri Oct 30, 2020 9:44 am
Forum: Other SDR Devices
Topic: Modify RTL-SDR Wideband LNA for HackRF TX
Replies: 3
Views: 817

Re: Modify RTL-SDR Wideband LNA for HackRF TX

There are many prebuilt and modules for amplifier available. The price increased with frequency, bandwidth, amplification and power out. There are not only only harmonics to consider, but also Out Of Band (OOB) emissions, which can produce interference. The severity of OOB emissions depends among ot...
by snn47
Fri Oct 30, 2020 9:33 am
Forum: Antennas
Topic: When antenna isn’t in use best practice
Replies: 4
Views: 832

Re: When antenna isn’t in use best practice

@VE3AER congrats for beeing lucky at your QTH, but this does not mean other people will be that lucky. Even if there is not a direct lightning hit into an antenna, there are also secondary effects by lightning, which are spikes induced on wired connections. These can be equally sufficient to destroy...
by snn47
Fri Oct 30, 2020 9:03 am
Forum: RTL-SDR Discussion
Topic: Can I use the SDR very close to the RF source?
Replies: 12
Views: 15369

Re: Can I use the SDR very close to the RF source?

There is a similar discussion ongooging which provides additional information
see viewtopic.php?f=1&t=6158 To near to the RF source?
by snn47
Tue Oct 27, 2020 3:01 pm
Forum: RTL-SDR Discussion
Topic: To near to the RF source?
Replies: 4
Views: 982

Varying voltage with antenna type and location on antenna

There is no simple answer to your questions, it depends on many factors and not how close you are to the antenna. The voltage on an antenna changes with antenna type, it's voltage distributions and therefore the position. The voltage changes therefore with where you come close to or touch an antenna...
by snn47
Sun Oct 04, 2020 9:30 am
Forum: Signal Identification Help
Topic: About 40 signals around 430Mhz in France (audio sample)
Replies: 3
Views: 979

Re: About 40 signals around 430Mhz in France (audio sample)

@username 1) its some Weird Amateur Radio stuff 2) its "just" noise To 2) Noise would not have distinctive frequencies, be not repetivie and would be diffuicult to generate with the strength you see here. To 1) Why is it weird just because it is in the 70 cm Ham-band? The 70 cm is in part shared wor...