Search found 72 matches

by snn47
Sat Dec 30, 2017 2:35 am
Forum: Off-Topic
Topic: GPS Clock Project
Replies: 6
Views: 440

Re: GPS Clock Project

Josh, Do you have a source for the 1 Hz out on PS2 that you can post, was it only special chipsetset like SIRF 3 or SIRF4? I gave my NL-603P to a friend long ago and will ask him next week if he still has it. I just checked a number of PS2 GPS mouses are still on sale in Europe e.g. - Navilock NL-40...
by snn47
Fri Dec 29, 2017 3:36 am
Forum: RTL-SDR Discussion
Topic: Finding Bugs using a SDR
Replies: 0
Views: 165

Finding Bugs using a SDR

Bugs using RF have been used for a long time to listen/spy on people. When telephones still had separate microphone and speaker capsules, replacement capsules containing bugs were sold. Compared to 30-40 years ago, when only discrete components were available bugs, the bug size decreased with the th...
by snn47
Thu Dec 28, 2017 10:41 pm
Forum: Antennas
Topic: Interesting old antenna, could use help identifying
Replies: 3
Views: 336

Re: Interesting old antenna, could use help identifying

Folded Ground Plane, Folded Monopole think of it as a folded fullwave dipole cut in half on a groundplane (using 1/4 wave elements), similar to a round plane is a half wave dipole cut in half on a groundplane. Unlike most groundplane antennnas using a 1/4 or 5/8 lambda radiator, the benefit is that ...
by snn47
Thu Dec 28, 2017 9:02 pm
Forum: Antennas
Topic: Low Frequency Antenna
Replies: 11
Views: 965

Re: Low Frequency Antenna

If you want to buy an active antenna using a in relation to the lower wavelength (15 000m) very short whip (0.02 m) look here http://www.bonito.net/boni-whip/en/index.html or from R&S https://www.rohde-schwarz.com/us/product/hfh2-z6e-productstartpage_63493-472072.html For those who want to have more...
by snn47
Thu Dec 28, 2017 7:40 pm
Forum: Antennas
Topic: Links to intersting Antenna literature - HF
Replies: 0
Views: 145

Links to intersting Antenna literature - HF

Sometimes entering the wrong combination of search words, can provide interesting results you wouldn't find if you were looking for it. I thought it would be helpfull to have a thread with such antenna related documentation, since I just stumbled over this TI Technical Application Report. It provide...
by snn47
Sun Dec 24, 2017 2:41 pm
Forum: Other SDR Devices
Topic: Airspy+spyverter vhf unusable
Replies: 3
Views: 308

Re: Airspy+spyverter vhf unusable

As dlritter wrote either remove the converter or use an antenna switch. Using a coax T-connector is for may reasons not recommended.
by snn47
Sun Dec 24, 2017 2:34 pm
Forum: Antennas
Topic: Low Frequency Antenna
Replies: 11
Views: 965

Re: Low Frequency Antenna (<400 kHz)

If it is your own key you want to receive a small loop in close proximity should be sufficient to couple enough energy into your Rx. Antennas for large wavelength 2400 m at 125 kHz or lower the size of a quarterwave antenna is already large, even for military uses. Therefore the antenna needs to be ...
by snn47
Sun Dec 24, 2017 5:06 am
Forum: Antennas
Topic: SDR Antenna Analyzer
Replies: 3
Views: 549

Re: SDR Antenna Analyzer

What frequencies do you want to use it for? RTL-SDR is correct, that is the basic design used in many short wave HAM Antenna Noise Bridges, that use a receiver as detector. The noise of a zehner diode will decrease with frequency. The trick was to find a zehner diode that produced high noise to star...
by snn47
Mon Nov 27, 2017 8:57 pm
Forum: Troubleshooting Help
Topic: USB Isolator + RTL-SDR V3 "no device selected"
Replies: 6
Views: 509

Purpose of USB Isolator

PS.: What do you hope to gain by using a USB isolator? From my understanding USB isolator are intended to provide galvanic isolation for the USB Ports only, e.g. for medical purposes, but are also used by audiophiles. Optical Isolator are in my understanding not intended to necessarily eliminate noi...
by snn47
Mon Nov 27, 2017 8:31 pm
Forum: Troubleshooting Help
Topic: USB Isolator + RTL-SDR V3 "no device selected"
Replies: 6
Views: 509

Some USB 2.0 Isolator

I just did a quick check and found a cheaper one that is USB 2.0 only https://www.reichelt.de/?ARTICLE=179183&PROVID=2788&gclid=EAIaIQobChMI36aDtMjf1wIVi0AbCh1FtgY2EAQYAyABEgKdOPD_BwE for 249 €. Some are based on Analog Devices ADuM3160. The chip is only 7,30 €? https://www.reichelt.de/?ARTICLE=1135...