SDRplay Community Forum

Just tried your websdr on my smart phone (since I'm at work and company firewall blocks non standard ports) and it worked fine. Heard a EA7 station on 40m SSB. Nice!

Phil.

I don't listen much above 160 m these days, but I think the upper roll-off must be pretty slow as MW and 160 both seem just as lively as ever.

DK7OB wrote:Just tried your websdr on my smart phone (since I'm at work and company firewall blocks non standard ports) and it worked fine. Heard a EA7 station on 40m SSB. Nice!

Excellent.

Did a bit of fine tuning:
- increased the dynamic range of the waterfall and reset it's default level
- removed audio and FFT compression which improved the fidelity of audio and waterfall
- increased the sample rate. RF receive bandwidth is now around 6.9MHz to 7.4MHz

p.

/edit
- restored the audio and FFT compression, unfortunately the difference in internet network bandwidth of compressed to uncompressed is 200kbs v 1.3mbs

g1hbe wrote:I don't listen much above 160 m these days, but I think the upper roll-off must be pretty slow as MW and 160 both seem just as lively as ever.

Hi again Andy, I must try your approach, extending the bottom rolloff downwards so as to preserve general HF operation is all I've done. Thanks for your comments and input.

Regards,

p.

Well in my case RSP1A is better than RSP2.
As I've already posted here (viewtopic.php?f=7&t=2797) about my internal noise issues, I only have one such spur on RSP1A, but two on RSP2 !



RSP2 without any antenna attached on CubicSDR on a MacBook: (I've the same situation in other harmonics of these frequencies, like near the 40m band)

More info about my above post:
1- I'm sure a lot of you already know: changing the IF mode, changes these frequencies;
2- In Zero-IF mode, these are my spurs on RSP2:

2.297MHZ , 2.326MHZ
4.599MHZ, 4.658MHZ
6.906MHZ, 6.993MHZ
9.187MHZ , 9.300 MHZ
and on and on. These "pairs" are only visible below 16MHZ. There are other spurs on higher frequencies but they're not "pairs"

On RSP1A with Zero-IF:
2.519MHZ , 5,030, 7.533 , etc

These numbers probably will change with time/temperature but I didn't test that.

P.S: These spurs do not interfere with my daily experience and I can safely ignore them. But investigating the root cause and being able to attenuate them in future versions would be good.

Just for laughs I show my Hammy Hambone solution for the spur in the 40m band. It's a 47 Ohms 1206 SMD resistor connected to 5V and glued to the offending chip. The ~0.5 W dissipation creates enough heat to move the spur down to 6.92 MHz.

Merry Christmas and a happy new year!

DK7OB wrote:Just for laughs I show my Hammy Hambone solution for the spur in the 40m band. It's a 47 Ohms 1206 SMD resistor connected to 5V and glued to the offending chip. The ~0.5 W dissipation creates enough heat to move the spur down to 6.92 MHz.

Merry Christmas and a happy new year!
2017-12-23_14-06-20_v1.jpg

Good one!

Have a good holiday break, everyone.

Phil