Search found 66 matches

by qrp
Wed Oct 07, 2020 3:18 am
Forum: RTL-SDR Discussion
Topic: ExtIO_RTLSDR_u8.dll with HDSDR 2.76 + dongle
Replies: 16
Views: 13213

Re: ExtIO_RTLSDR_u8.dll with HDSDR 2.76 + dongle

I am noticing that it looks like the noise floor has moved up almost 30db compared to normal levels using the RTL2832 extio. Noise floor is exactly the same. The difference is because this extio uses 32 bit sample format instead of 8 bit which is used in standard extio. Since it uses different samp...
by qrp
Tue Sep 01, 2020 10:10 pm
Forum: RTL-SDR Discussion
Topic: Direct sampling to bandwidth output, how done?
Replies: 10
Views: 3732

Re: Direct sampling to bandwidth output, how done?

Anti-alias filtering can be implemented in software or hardware by many different methods Anti-alias filtering can be done in hardware only for analog signal (before ADC). This is impossible in software (in digital domain after ADC output). The only way is to apply anti-alias filter to the analog s...
by qrp
Sun Feb 23, 2020 1:34 pm
Forum: Other SDR Devices
Topic: Automatic notch-filter for SDR# ?
Replies: 2
Views: 5314

Re: Automatic notch-filter for SDR# ?

use HDSDR, it already has automatic notch filter
by qrp
Sun Feb 02, 2020 3:20 pm
Forum: RTL-SDR Discussion
Topic: Lots of activity on RF, is it all real?
Replies: 6
Views: 4904

Re: Lots of activity on RF, is it all real?

Most of them are "fake signals". The source may be different, most of them are spurs from internal oscillators. Others are intermodulation products due to non-linear distortion in the RF frontend. And some of them are just images mirrored from different frequencies across spurs. The quality of recei...
by qrp
Sun Feb 02, 2020 3:13 pm
Forum: RTL-SDR Discussion
Topic: Broadcast AM filter - RF power tolerance?
Replies: 5
Views: 3982

Re: Broadcast AM filter - RF power tolerance?

it depends on how much power will be consumed on filter components due to heat loss, so technicaly it depends on the filter component quality. Better inductors and capacitors Q-factor, leads to smaller heat loss. Also it depends on capacitors maximum voltage. Usually SMD capacitors have 25-50 V limi...
by qrp
Fri Dec 20, 2019 9:39 am
Forum: RTL-SDR Discussion
Topic: AM frequency help with rtl-sdr USB
Replies: 24
Views: 12129

Re: AM frequency help with rtl-sdr USB

you can listen aircraft AM band (118–136.975 MHz) with any RTLSDR dongle. There is NO needs up/down converter for that. You can do it with RTLSDR, but the signal is weak, so you're needs good antenna and may be bandpass filter and LNA
by qrp
Mon Dec 16, 2019 10:29 pm
Forum: RTL-SDR Discussion
Topic: ExtIO_RTLSDR# - custom ExtIO for RTLSDR
Replies: 36
Views: 49421

Re: ExtIO_RTLSDR# - custom ExtIO for RTLSDR

how is possible to reduce the RF gain ? In particular on low hf bands where the noise is so high. There is no way to tune gain for direct sampling mode on RTLSDR dongle. Because there is no hardware which allows to change gain. Gain can be tuned for tuner, which is not used in direct sampling mode....
by qrp
Fri Dec 13, 2019 2:31 pm
Forum: RTL-SDR Discussion
Topic: ExtIO_RTLSDR# - custom ExtIO for RTLSDR
Replies: 36
Views: 49421

Re: ExtIO_RTLSDR# - custom ExtIO for RTLSDR

ik3jls wrote:
Fri Dec 13, 2019 7:31 am
Where can I find SDRuno v1.2 ???
sdruno 1.33 doesn't supports ExtIO.

You can download sdruno 1.2 with ExtIO support from sdrplay site download page:

https://www.sdrplay.com/downloads/
by qrp
Fri Dec 13, 2019 2:28 pm
Forum: Troubleshooting Help
Topic: Rising noise floor at tuned frequency?
Replies: 5
Views: 3327

Re: Rising noise floor at tuned frequency?

tim_rtd wrote:
Thu Dec 12, 2019 2:10 pm
Try clicking that Correct IQ button.
swap I/Q cannot help with noise floor, it just mirrors frequencies around DC (LO frequency)
by qrp
Tue Dec 10, 2019 12:13 pm
Forum: Other SDR Devices
Topic: RTL SDR dont work on Asus Prime B350 Pluse + Win7 x64
Replies: 11
Views: 28033

Re: RTL SDR dont work on Asus Prime B350 Pluse + Win7 x64

rtlsdrblog, it is linked with libusb 1.0.22-rc4, this version of libusb has a bug fix for usb3 issue for a new motherboards.