Sunday, November 27, 2011

SDR Meets DJ Gear

Hi there! Some of you may know that I am quite busy with music, dance and the stuff concerned.
Some rare occasions have it, and hamradio mixes with music mixing, aka DJing. And here is one of those occasions:
The DJ Mouse
http://www.dj-mouse.com/
Basically, there is nothing special about this mouse, other than the regular scroll wheel is somewhat wider and parallel with a jog wheel. It is just this jog wheel that makes all the difference.
All SDR software solutions I am aware of, are using the scroll wheel for sweeping the frequency. I always felt that this was somewhat awkward. Now we got a mouse with a rotary encoder, just like a VFO knob.
Still I scratch my head what can be done with the "scratch" button...

Thursday, November 24, 2011

Central Heating Aerial

Dear readers, there was not much going on here lately, sorry about that!
Today, some weird incident triggered another thought in me.... and here it comes:

Returning home, I felt an unfamiliar chill in my house... That's no good, I thought, and checked the central heating system, which indeed was dead. Quick check and the culprit was found. The expansion vessel (expansievat, Ausdehnungsgefäss, vase d'expansion, whatever you wanna call it) leaked. The local hardware store was still open, hence I hurried up to get a replacement of similar size.
Just €22.- will get you one with a 17l capacity.
Speaking of capacity, that came to my mind on my way back home. What about using the defective one as top-capacity for a short vertical? The roundish things got a nice thread which would easily fit Cu pipes and respective fittings.
The vessel itself is made from steal (Fe) most likely. OK, that's somewhat on the heavy end, electrically however, not that inferior to Al, which is used most.
The plan is to build a short tapered vertical from Cu-pipes with an expansion vessel on top.
I figure, one may also consider a short loaded dipole.
Possibly, just 2 of such vessels could make a broadband dipole for VHF.... one could also think of a broadband vertical for VHF, using just one vessel on a ground-plane.

There may just be one down-side, your neighbors will think you're completely mental, putting the expansion vessel of your heating system 5m above your roof ;-)

Happy experimenting.

Tuesday, November 8, 2011

Most Interesting

What is going on here? A local station, a dx station and the radar, which seems to dislike the condx...


Broad-Band Aerial Update

Short update on the 11m half-wave aerial conversion.

The 4:1 UnUn is placed, that was one of the two options. Actually, this was the easy option, since the UnUn came wound up and ready to use from a surplus dealer.

11m half wafe aerial base portion
The arial, about 5.5m long, w/o any further modification could be matched easily with the IC-703 builtin tuner on the band from 80m to 10m, with the exeption of 30m. I figure, some additional Al-tube extension could solve that problem.