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Messages - Tom S

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61
Huh? / Re: The World Cup of Soccer
« on: June 20, 2014, 1510 UTC »
If it were a real sport then they'd allow tackling.

62
Where did you find that picture of Fansome at Field Day, Tom?

It was in his government file.

63
Equipment / Re: Gear required to take the step
« on: June 20, 2014, 1504 UTC »
As far as receiving signals from far distances, your antenna is more important.  The receiver can only work with what signals are fed to it from the antenna system, and if you're not getting signals down the coax cable then your receiver won't have much to hear.

That being said, you probably don't want to skimp too much on the receiver, either.  Make sure you get one which has SSB coverage.  A lot of SW receivers, especially portables but also some table tops, are AM-only.  You'll be missing out on a lot of signals, and an AM-only receiver is useless for utility DX'ing since just about all signals are either SSB or digital.  I'm willing to bet that most $50 SW receivers are AM-only.

Other things to look at receiver-wise are sensitivity and selectivity.  Sensitivity means how well the receiver can hear signals, and selectivity means being able to tune out the signals you don't want to hear in favor of the one you want to hear.  It's annoying trying to listen to a weak station while having nearby interference blocking it out, or trying to listen under images from the AB broadcast band.

64

65
Equipment / Re: Gear required to take the step
« on: June 19, 2014, 1622 UTC »
If that "ultra wide band SDR" really is just an RTL dongle with an HF converter, I'd personally avoid it. For about the same money, or maybe a little more, look into a used communications receiver?

Nothing wrong with an RTL dongle and HF converter, but I don't know that I'd recommend one for a newbie.  Mine does take a bit of frequency tweaking until the crystal oscillator in the converter settles down.  But "for the money," I have roughly $25 involved in my SDR setup.  I'd love to find a decent communications receiver for that price.

66
Equipment / Re: Gear required to take the step
« on: June 19, 2014, 1619 UTC »
This is one thing I was wondering about. I certainly am not as educated on the ins and outs of antenna systems as I'd like to be. You mentioned a 9:1 balun, what exactly are you referring to? And what kind of wire works best for this situation?

A 9:1 balun is simply a transformer which helps bring the high impedance of an end-fed wire antenna down closer to the 50 Ohm impedance of most communications receivers.  It also allows static charges on my 140' wire to bleed off to ground instead of into the radio.

More information here:  http://www.abcelectronique.com/annuaire/montages/cache/1790/antenne-mf-et-hf.html  Scroll down to "9:1 UNUN."  An unun is basically the same thing as a balun, only both sides are unbalanced.  I built mine just like in that picture, using 30 turns on the primary (antenna side) and 10 turns on the secondary (radio side).  Then one leg of each side is connected directly to ground.

The wire I used was just standard magnet wire, since this was for a receiving antenna only and I wasn't going to be transmitting with it.  If I were to transmit on it I'd have used some heavier wire.

67
Huh? / Re: Chuck Norris the DXer
« on: June 18, 2014, 2128 UTC »
Chuck Norris doesn't wait for good propagation.  He ionizes the ionosphere just by staring it down.

68

69
10. Beginning in 1969, Kasem voiced the character Shaggy for the animated series "Scooby-Doo: Where Are You!" He continued to voice the long-haired hippie in TV, film and video games until 2009.

And he would have gotten away with it if it hadn't been for you meddling kids.

70
Huh? / Re: TV Antenna?
« on: June 17, 2014, 2152 UTC »
I plan on putting up an old 4 element bowtie panel antenna in place of our satellite dish, and then using the cable from that to feed into the house.  I was planning on using that antenna to monitor milair comms from the bomb range about 100 miles away, but some sacrifices need to be made to keep the wife happy.  I can still pick up the aircraft over the bomb range on my military surplus discone anyway.

71
Equipment / Re: Gear required to take the step
« on: June 17, 2014, 2146 UTC »
Whatever radio you get, don't skimp on the antenna.  Right now I'm using a 140 ft. random wire fed through a 9:1 balun and it's one of the best antennas I've ever used.  If the trees on my property were situated differently, I'd convert it into a horizontal loop.

The antenna is the most important part of your listening setup, because without a good antenna that fancy radio will be little more than a paperweight.  And generally speaking, the more wire you can get up high outside, the better.  It doesn't have to be expensive, either.  Just spend a few bucks on a roll of wire and get it up high between a couple trees and you'll be in business.

72
SDR - Software Defined Radio / My SDR
« on: June 17, 2014, 0323 UTC »
Here's a little article on our local radio club website about my SDR system using an R820T DVB-T dongle and homemade HF converter for signals <25 MHZ.

http://www.sekarc.net/2014/02/sdr-at-builders-meeting_24.html

The HF converter was built into an old Nokia bag phone case.

73
Equipment / Re: IC-R70: Icom's forgotten gem
« on: June 17, 2014, 0313 UTC »
I agree with the trimmer caps comment.  IIRC there were four of them for four different frequency ranges, and when I bought my R71A one of the bands wasn't working until I tweaked the cap.  Seemed like every so often I had to tweak them, and temperature was a factor.  Seemed like I had to tweak them when the seasons changed from warmer to cooler and vice versa.

Mine had the remote control but I rarely used it since the radio was right there on my radio desk.

74
Equipment / Re: Portable HF Antenna question
« on: June 17, 2014, 0251 UTC »
It looks like it's a homemade version of the Pac 12 portable ham antenna.  The Pac 12 has different coils for different bands.  I've seen them in use by hams running QRP, and it's amazing how well they actually work for such a short antenna.

75
No copy in SE Kansas.

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