Search found 21 matches

by Github
Fri Apr 12, 2019 5:49 am
Forum: Antennas
Topic: What antenna is this
Replies: 1
Views: 282

What antenna is this

Hey guys, I recently disassembled an antenna for L band satellite communication, but the structure inside is something I never seen before. There are two pcb boards sits in parallel, no wire is connected between two plates. I took some photos of them, however the underneath board cannot be taken out...
by Github
Sat Mar 16, 2019 1:36 am
Forum: Antennas
Topic: What antenna connector is this?
Replies: 2
Views: 635

Re: What antenna connector is this?

dlritter wrote:
Mon Mar 11, 2019 5:30 pm
it looks like an SMB connector
http://www.l-com.com/coaxial-caoxial-ad ... ack-female
The original connector has split on insulator (outer shell), but SMB doesn't have. I've bought a MCX connector with similar rings on the bottom to see if it fits :)
by Github
Sun Mar 10, 2019 3:25 pm
Forum: Antennas
Topic: What antenna connector is this?
Replies: 2
Views: 635

What antenna connector is this?

I'm going to DIY an antenna for this phone, but the antenna connector seems weird. It has exactly the same length and diamater as a MCX connector, but it's longer. The whole part after that black rubber band (marked in photo) goes into the phone. Anyone have any idea about this? Much appreciate! Pic...
by Github
Thu May 24, 2018 4:08 pm
Forum: Off-Topic
Topic: Question about frequency mixer?
Replies: 1
Views: 2660

Question about frequency mixer?

I am confused about how does frequency mixer actually work. As we know, if we mix a 5 Mhz and a 20 Mhz signal together, it generates 15 Mhz and 25 Mhz signal (ignore harmonic wave for simplicity). If we connect the signal to spectrum analyser, we'll see four signals, 5 15 20 and 25 Mhz. But here is ...
by Github
Sat Mar 03, 2018 5:56 am
Forum: Troubleshooting Help
Topic: rtl sdr v3 bias tee driver not working
Replies: 6
Views: 2972

Re: rtl sdr v3 bias tee driver not working

I putted my code back to the old computer and did some small changes, it now works on both computers. The correct code should be rtl_biast -b #bias t status -d #device number 0 means bias t off and 1 means on default device number should be 0, but I don't know which device is using number 0 on my ne...
by Github
Sat Mar 03, 2018 5:42 am
Forum: Troubleshooting Help
Topic: rtl sdr v3 bias tee driver not working
Replies: 6
Views: 2972

Re: rtl sdr v3 bias tee driver not working

Problem is solved now. I edited the cmd file, the correct command to turn on bias t should be rtl_biast -b 1 -d 1 The command to turn of should be rtl_biast -b 0 -d 1 In the original file, turn on bias tee is rtl_biast -d 0 -b 1 Turn off is rtl_biast -d 0 -b 0 Note that I change the position of -b a...
by Github
Fri Mar 02, 2018 5:15 am
Forum: Troubleshooting Help
Topic: rtl sdr v3 bias tee driver not working
Replies: 6
Views: 2972

Re: rtl sdr v3 bias tee driver not working

Both computers are running windows 10 with lastest update.
by Github
Fri Mar 02, 2018 5:14 am
Forum: Troubleshooting Help
Topic: rtl sdr v3 bias tee driver not working
Replies: 6
Views: 2972

rtl sdr v3 bias tee driver not working

I recently built a new computer and copied all sdr softwares from my old computer, everything works fine except bias t driver. On my old computer it works without any problem, command line says found rafael rtl2832u device, then bias tee is being turned on. But when I copy this folder to my new comp...
by Github
Mon Feb 26, 2018 8:47 am
Forum: Antennas
Topic: Is it normal for an antenna not have lowest swr in its advertised band?
Replies: 7
Views: 3969

Re: Is it normal for an antenna not have lowest swr in its advertised band?

AcidJazz wrote:
Mon Feb 26, 2018 6:46 am
First of all, gain 49.6 is too much, I think. You need to try change gain for the maximum dynamic range.
If I set the gain too low, I can't see any obvious dip on the curve.
by Github
Mon Feb 26, 2018 5:44 am
Forum: User Projects
Topic: DAB(+) Decoder!
Replies: 2
Views: 4000

Re: DAB(+) Decoder!

It always stop work after about 10 - 15 mins playing. I've tried sdr-j and it is almost the same. Finally I installed offical driver which makes the dongle work at hardware decoding mode. SNR is improved a lot and no more stop working. Maybe I need a better computer?