How to get started? Stuck at a root prompt

johnbabrick

I just got the Kiwi setup on the beaglebone black and powered it on... and I get to a root login on a terminal. Is there supposed to be some sort of desktop manager? Am I supposed to start something on the beaglebone to get it running? How do I connect to it from another system? I have the beagle bone connected to a hub with this Linux computer this computer has an IP assigned of 10.42.0.47... the beaglebone says it is at 192.168.7.2... I cannot ssh from the laptop to the beaglebone... what am I doing wrong?

johnbabrick

Am I supposed to be connecting the ethernet cable to the ethernet jack on the beagelbone? 

I have a Ubuntu computer sharing a wireless network to a hub. The laptop and the beaglebone are connected to the hub. The IP address of the laptop is 10.42.0.147. I don't know what the IP address of the beagelbone is.

jks

All of these questions are covered in the printed Quick Start Guide included in the box with every Kiwi board or kit version shipped (also online here: http://kiwisdr.com/quickstart/quickstart.pdf)

There is also much more extensive documentation here: http://kiwisdr.com/quickstart/index.html

johnbabrick

I read all that. Apparently, I cannot connect through the shared wireless connection on the Ubuntu machine... I have to be connected directly to the router downstairs.

jks

I'm sorry, your description is a bit confusing to me. When you talk about 192.168.7.2, that is an IP that is only ever associated with a networking connection using a USB cable between a computer and the Beagle (192.168.7.2 is the Beagle side, 192.168.7.1 is the computer side). Our documentation talks about doing this as one option of trying to figure out what IP address your network DHCP server has assigned to the Beagle Ethernet interface. Is this what you have done?

Our doc is missing a description of what to do once you are logged into the Beagle over USB (I will fix this). When logged in using the root account type the "i" (letter i) command. This is an alias for the longer "ifconfig -a". It will display all the IPs for each network interface on the Beagle. The first should be for "eth0" which is the Ethernet. It should say something like "inet addr:192.168.1.103" (assuming it is plugged into an active network).

You should then be able to use this IP to connect to the Kiwi server from a browser, e.g. http://192.168.1.103:8073/ even from a computer on a wireless segment of your network that might be on a different subnet, e.g. 192.168.2.nnn

A DHCP assigned address may change over time so you need to use one of the methods described in the docs to "lock down" the IP it gives you (by associated it to the MAC address of the Ethernet interface) or by changing the Ethernet IP to a static IP outside the range of IPs assigned by DHCP (change it on the "network" tab of the Kiwi admin page at e.g. http://192.168.1.103:8073/admin)

johnbabrick

OK, I worked through some local networking issues here and have the kiwi working. Some of the confusion is that I was of the mindset that I would be setting the kiwi/beagle up with a keyboard, mouse and expecting it to boot to a desktop... all of which is not the case. Perhaps some more explicit instructions pointing out that the kiwisdr is expected to operate as a standalone headless computer, and that all access to the kiwisdr will be from another computer on the local network that will access it through a web browser. This was not obvious to me and so I was confused. 

Now the issue is that I have the kiwi running and I see a waterfall display. I then hooked the kiwi up to a random length wire antenna hanging out of my window... and there seems to be no signals at all. None. Nada. I thought I saw something on the forum or in the instructions about this but I cannot find it now. Any help?

jks

Given where you are (assuming the IP address recorded by the Forum is meaningful) you should be able to touch the pins of the SMA connector that connect to the PCB with your finger and have the AM broadcast band (~540 - 1700 kHz) light up.

If you're using a long wire connected to the green terminal block be sure you're on the leftmost terminal as you look with the connectors pointing at you, edge-on, from the top (it's marked 'ANT' on the silkscreen). Make sure the wire is really making contact with the metal clip of the terminal. Those tiny terminal blocks are fussy. Especially is you use too small of a wire gauge. If using solid wire sometimes I'll fold two or three loops of the wire, like a paperclip, on the end to give the terminal clip something more to grab onto.

With a wire antenna I would try different grounding configurations first to try and get an improvement in noise. If the noise floor on the spectrum display is well above (more positive than) -90 dBm then local noise is dominating the situation.

Here's what happened when I did the finger test to the development Kiwi sitting next to me. I preset the "band" menu to MW and turned on the spectrum display. With nothing connected the waterfall is a medium light blue, the S-meter reads S1 and the spectrum is flat at about -120 dBm. Touch the SMA pins and all kinds of noise appears at the low end of the band (probably because my other hand is on the laptop to take the screenshot and picking up display noise). But a -90 dBm local AM station appears at 1440 kHz no problem.

jks

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/42/b6a01e34bf7a3e3eaae7e250b56345.png

johnbabrick

Thanks for the help. 

I was able to detect faintly a few AM broadcast stations. I seem to have an extraordinary EMI problem here. I am in a subdivision that consists of closely spaced houses and does not allow antennas. So, for the moment I've been trying a random length wire hanging outside my window and comparing that wire between the kiwi and the IC-7300 I find that I can't seem to hear anything but S9+10 noise. Sigh. I plan on moving from here in the summer, so perhaps the next move I will take into account the RF noise factor before I sign a lease. 

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/54/49a5deadf3ab251dd18b857d661e7b.png

johnbabrick

And I'd like to add that overall this system - the KiwiSDR, the software setup on the Beaglebone and the web interface is an extraordinarily well done technical accomplishment. I am an embedded software engineer by trade and I think I know what I am talking about here. Nice job. 

jks

Well don't give up just yet. I'd like to see an image with the "WF min" slider set at -100 or -90 instead of -140 (when zoomed all the way out). And also with the spectrum turned on. That will give us a better idea of what your noise floor is really like and what kind of interference it is. It's difficult to judge, for me at least, when WF min is set at -140 because the colors for the quietest signals will be in a range that doesn't have any brightness change (e.g. black to blue), only color change (yellow to green). So this tends to wash out the finer detail you want to see when judging noise level.

The other possibility is what occurred in this thread: http://forum.kiwisdr.com/discussion/discussion/492/help-diagnosing-interference-issues

It was a really bad case of RFI from a UPS with strong harmonics every 30 kHz extending to 30 MHz. When that happens the 0-30 MHz waterfall looks like a solid wall of noise because the strongest signals in each "bin" of the FFT is displayed. So the peaks of the RFI harmonics are all you see.

Ideally you could also put your Kiwi on the net (i.e. open port 8073) and email the IP to support@kiwisdr.com) so I can look more closely. No need to list it on sdr.hu to do this.