Re: LF: testing VLF grabber

["Max IK0VVE" <ik0vve@ik0vve.net>]

Stefan, all,

I do not have time to reach you that you already run away to lower frequencies, HI.

I passed the last nights to try to discipline my audio board with my 1pps GPS... nothing to do, I've tried all, levels, phases, etc... I followed the Wolf's tutorial without success. I suppose duty cycle is to low. I'm waiting for a new GPS so I'll try with that or in the worst case with an OCXO+GPS 10khz.

So only for test now I'm pointing to German LF station DHO. Inserted BP and NB and moved to about 100uHz the resolution of the grabber.

Tomorrow a little trip, not so far, to an Ham friend to listen if his zone is quieter than where I live.

I'm interested to your Raspberry Pi remote system, can we get more informations?

Thanks, 73, Max IK0VVE

______________________________

 

...here some of my HAM Radio projects...

SkyGeM Rotator

AntennaDinamica

RCR-DX

www.ik0vve.net

Da: owner-rsgb_lf_group@blacksheep.org

A: rsgb_lf_group@blacksheep.org

Cc:

Data: Tue, 03 May 2016 11:32:55 +0200

Oggetto: Re: LF: testing VLF grabber

Hello Max,

Perfect. A nice progres!

Am 03.05.2016 02:47, schrieb Max IK0VVE:

A perfect place could be the remote station of RCR-DX in monte Ripoli near Tivoli (http://www.rcr-dx.eu/r-c-r-.html JN61JW) internet connection 50Mbps UP/DW! But it is not so close to my home and I need an hour and half or more to reach this place, if any problem occur I could spend a day to solve it! So for now I would see some place nearby. 

Yes, a local site in just a few km distance is a very nice thing! And it may be better to have your own site, without any neighbours who could run a noisy power supply. When it's all your, then you can remove, replace, modify any QRM sources without discussions and compromises!
Do you also plan to run it with solar power? My system has no problems any more since the end of February. And in winther there were a few things running sub-optimal since the project was very new to that time.

Rick (IW4DXW) and Dom (IZ7SLZ) are each about 680 km far from me, the first to North and the second to south east.

Oh, that's very far. I rather expected something like 20 km.

I know Rick is transmitting in these hours.

Hmm, he doesn't tell us.

Yesterday I've chenged the RX antenna from 60 wires loop to the TX (un-tuned) antenna of 630m, I've seen signals growing all over the band.

What does that mean? An overloaded RX? With such a large antenna on the soundcard you will need a low pass filter. Simple RC chains would work well. Maybe 2x 10kOhm + 1nF.

So also this could be a point of discussion for the next remote station. May a single turn loop antenna be good also for me?

Yes sure. These days i am very convinced from loops.
If you also want to use a Raspberry Pi for remote controlling the system, you can easily use some mono stabile relays to switch between different antennas, maybe 2 loops and an E field antenna.

73, all the best
Stefan

I'll keep the list updated about my grabbers.

Thank and 73, Max IK0VVE