Randomwire madness

[Michiganrailfan]

Rube Goldberg and un uns

Folks,

I'm confused as two why an un un is needed for SWL. I have about 100 feet of coax stretching into the back yard before it makes a transition to 100 feet of randomwire. I've been reading about mismatch of impedance. But the guy at Associated Radio says I don't need an un un if I'm receiving only.

Thanks

 

[a29zuk]

I wouldn't worry too much about the mismatch on HF. The more important thing is the signal to noise ratio. You have plenty of antenna to receive a good signal and it looks like your antenna is remote enough to keep the man made noise to a minimum.

I know some of the other posters went off topic in this forum but it was hilarious. The comedy is welcome here.

 

[ridgescan]

Are ya logging anything yet? If I can get Rwanda or Madagascar here with a 50' wire I want to see what you are getting out there without all the noise I have to fight here in the city.

 

[Michiganrailfan]

What I'm logging

Here are the English speaking stations I've received so far: Russia, Havana, China, Toronto, Spain, Albania (Tirana, very weak), Romania (Bucharest), Slovakia (Bratislava), Voice of America in Africa ?? (also weak), Taiwan.

Lots of Spanish speaking stations, lots of religious stations, lots of Ham.

I'm receiving mostly in the 6 to 7 MHz and then around 11 MHz. Everything else is empty of audible stations. I get plenty of Morse code, though.

I'm impressed with this $90 llittle radio (Softrock; includes $20 for the case). Recall the randomwire is only 3 feet off the ground (it's a hundred feet long, though).

The waterfall makes using the radio great.....I can see a number of stations at once; and then zoom in on the strongest first, the second strongest next, and so on.

Here's where the addiction comes in: how to get those weak stations. I'd say about half of the stations I can "see" on the waterfall are too weak for me to get much of an audible signal.

I don't yet have an un un on the antenna. I ordered one in the mail. Thanks for the offer, Xeno, but I decided to get one brand new. (It only cost $20).

I'm tempted to spend more money on a radio that'll bring in the weak stations. But I'm cheap - not rich. I had a nice talk with a guy at Universal Radio, who offered 2 suggestions:

1. Try out the Grundig Satellite 750....he said it's a great all around desktop for the money ($350)....something a guy could keep for years, take it camping, and so on.

2. Consider the SDR - IQ (price $500).

For both of the above options, I'd like to "drive one" and see how good it pulls in the weak stations.

Cheers

 

[ridgescan]

HA funny-I was the one who suggested the Sattelit750 to you in your first query about SWL and I got SPANKED by another guy here then you went off in a different direction from your original desire to have a "bedside radio". I still recommend it to you OR get what I have which is way more serious-the Icom IC-R75-you will spend $600 new but well worth it for a radio you will keep for LIFE and has filters enabling you to null and choke that weak station till it is copyable.
Your VOA Africa catch is way cool especially from your location! I pull Africa in strong here cause I am near the Pacific and have that to my advantage according to what I heard here. That shows your wire's doin it well. I'm going to give you the link to the spreadsheet we use here.
S H O R T W A V E S T U F F
click on the "B-10 combined" link and allow and open the page-clik the "combined" tab lower left to bring up the spreadsheet then scroll for freqs and times. ka3jjz provided this here and it is valuable. With that sheet and your strong antenna you can start logging DX with us in the SW section from Michigan and give k9rzz a run for his money there in Wisconsin

 

[Michiganrailfan]

Thanks for sending me the link to the spreadsheet, Ridgescan.

How does it work? Under "combined," is this a listing of selected stations worldwide?

Okay, how about some advice for a newcomer.....how do I learn the best way to move forward into the new world of "nulling and choking the weak station until it's copyable?"

I'm not sure, but I think I'm squeezing every bit of horsepower I can out of the Softrock.

What's the next quantum leap, in terms of buying a better receiver and not needing a degree in electrical engineering to run the thing?

I'm impressed with your ICOM IC-R-75.

But, frankly, SDR is tough to walk away from.... There's something about seeing a piece of the spectrum.....and then zooming in on peaks.

I have no idea if anyone makes a reasonably priced SDR that can match the ability of, say, and ICOM IC-R-75 to zoom in on weak stations.

Bottom line: I need to learn more......not sure if SDRs are ready for that kind of prime time......If a guy wants to eek out copyable signals from weak stations, this is where the thrill is. I'm trying not to pay an arm and a leg.

Cheers

 

[ridgescan]

In your case, I still have to say get the Sattelit750 and then KEEP the SDR too Then you have versatility in your post for around $400 total. I don't know what capabilities your Softrock has for tweeking sigs but on my R75, when I want to dig up a weak one I start with backing off the RF gain till it chokes to 30-40dB where I start to get a stabile voice copy and most of the noise is nulled, increase the volume here, then I have "pass band tuning" which offsets the carrier and tends to sharpen voice even more. Then I can throw on one or two filters more and even change combos there.
My R-71A which you see on all my videos, is not as capable as the R75 of nulling AM signals, BUT I have extra filters and an AM PBT ability that work on the AM signal already so I don't need to tweek on that one other than giving the PBT knob a turn.
Other guys out there will null an AM broadcast by switching to SSB which cleans it up too-but I personally like the challenge of keeping an AM broadcast AM. Anyways with your wire out there, IMO the Sattelit750 would be very nice.
If you want to take a chance like Nickcarr suggested a few weeks ago, you can pull the trigger on an R75 on Ebay OR you can check the USED sections online of Universal Radio or Ham Radio Outlet, who are decently trustworthy guys but also sell those radios "as is"

 

[ridgescan]

Far as the spreadsheet, what I like to do is tune the dial and search for broadcasts, then once I land on one of interest, I go to the spreadsheet and scroll to that frequency, coordinate the broadcast times, then I can ID who, what where from, power, target etc