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PostPosted: Sun Jan 01, 2012 2:56 am 
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Location: wpb fl
just got my longwire up into the trees, but not sure best way to run the leadin. i'm about 200 ft long, maybe 35 ft up, runs nw x se in se fla, and crosses the garage at about 40 ft from se end. i have coax at the garage that runs where i need it. it's the other end of the coax i'm jeswonderin about.

seemingly two options are, 1) connect coax at the se end of the ant and hang it from the ant wire as it crosses the 40 ft of driveway/parking area, until it is above the garage, then drop. or 2), connect the coax to the ant wire directly above the garage, either just tap into the ant wire or do a lopsided dipole out of it. one workshop is in garage.

the ant wire is plastic coated stranded 16awg. it's silver wire, kinda springy, not like soft copper, but solders easily. can't read the spool, too rusty. i have both ends on a conveyer rope system for easy downing, pulley on one end with tension weights. other end uses 12"pvc pipe insulator w/ holes drilled to connect wire and ropes.

kinda rushed it tonite, tired of just humming while i stare at unconnected xtal sets!

so, how to connect leadin?
jw

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PostPosted: Sun Jan 01, 2012 5:00 pm 
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Location: Saltford, Ontario, Canada
This is just a suggestion and feel free to try it or not. I would connect the centre conductor ONLY to the antenna in a place where the coax would hang straight down to your operating position. Do a really good job of sealing up the end of the coax with silicone or self-vulcanising electrician's tape.
At the radio end of the coax, connect the inner conductor to the antenna terminal, the shield to the ground terminal plus a single wire to earth ground from the radio's ground terminal. The shield of the coax being grounded should help to minimize pickup of the noise from electrical devices
in your house.

73, J.B., VE3EAR

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PostPosted: Sun Jan 01, 2012 5:08 pm 
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Location: South Florida
Agree with JB about the radio-side connection. As far as where to connect to the antenna, one end, rather than the center, is a good place to start. Random-length ntennas being unpredictable, you may find some stations are stronger with different connection points. Try it one way for a season, then try it another.

73,

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 Post subject: where..
PostPosted: Sun Jan 01, 2012 6:48 pm 
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Location: wpb fl
thanks, guys. my gut feeling was connection at the end points would be better, but logistics beg for an alternative.

maybe i just need to add to the work load and dig a trench from the nw end to the house for pvc pipe + coax(80 ft?), then run the coax thru the house or under the eves with the other stuff, to where i need it (another 100 ft?). other end, se, is across pavement, and i'm not up to trenching thru that.

i suppose my hidden question included this... what happens to antenna effectiveness when you tap into it not at the end, and another question, what happens to ant effectiveness if i break into ant and create an unbalanced (length) dipole? 140 ft and 60 ft.

hope all had a 5x9 new years eve. personally, i am optimistic about this new year, not that things will get better, only that i will be better able to cope with them.
jw

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 Post subject: Re: where..
PostPosted: Sun Jan 01, 2012 7:33 pm 
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jeswonderin wrote:
i suppose my hidden question included this... what happens to antenna effectiveness when you tap into it not at the end, and another question, what happens to ant effectiveness if i break into ant and create an unbalanced (length) dipole? 140 ft and 60 ft.

The traditional length of an effective wire antenna is one-half wavelength, and height also about one-half wavelength. At this length and height the antenna will show some directivity. The shortest half-wavelength antenna for the broadcast band is about 600-feet long, going to more than 1800 feet at the low end of the band. Anything significantly shorter, as is yours, is a compromise. So there is no absolutely certain "most-effective" way to connect to it. If you were trying only to hear a specific station, there might be, but you'd still have to experiment to find it, as surrounding objects also affect an antenna's pattern. The only way to determine the "best" connection is by experiment.

73,

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 Post subject: new ant cont'd
PostPosted: Mon Jan 02, 2012 3:04 am 
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Location: wpb fl
hooked up rg58 from se end of the aforementioned ant and ran it overhead to tv ant mast at garage. tv ant is at 16 ft, so is just high enough to keep rg out of trouble. rg is not dangling from ant wire as originally considered.

shield is isolated at ant end, and is available at radio end.

i'm running a sweat here, taking short cuts left and right. gotta hear some xtal!

so, for ground i'm using the shield of an old coax leadin from a defunct ant, which is coiled up hanging on garage outside wall, but still runs to the workbench. the shield of this coax was connected to power meter ground rod last time i used it several years ago. it still oughtta be good, right?

next, i grab a chinese 1n34a diode and a chunk of bulgarian galena, my vtg mag earphones and some clips, wire and other crap. the only coil i see is a vtg physics lab induction coil, iron core, like a 10 lb loaf of bread.

i'm frothing at the mouth by now so i start hooking stuff up left and right. i used the typical configuration, ant on one side of coil, gnd on other side. off ant side i go thru diode into phones, then phones to gnd side of coil. ran out of alligator clips. vice grips will do.

shaking like a leaf with anticipation, i place the phones on my head.

SOUNDS!
several at once, but couple are pretty loud. gads am i ecstatic. been too long away from it, i guess.

now the fun begins. the shield of the ant coax is just dangling, not connected to anything. if i connect it to the gnd side of the coil, i get one station only, and quite loud and clear. boy, that's neat. until the station id announces seaview radio, 95.9 FM! wth???? hmmmmm.

i'm surprised, but not shocked. weird stuff happens. seaview radio also broadcasts on 960 am, but the guy said fm, not am. when multi stations are heard, wjno am1290 is the loudest.

i'm sure i'll get this all sorted out when i get serious about it and start connecting some tuning parts and pieces. until then, i'm dissipating my anxiety with this foolishness.

why fm, though?

later, i'll post something on the proper forum about my bulgarian experiment.

jw

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PostPosted: Mon Jan 02, 2012 3:11 am 
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Location: Boise, ID
Why FM? There are a couple of stations that simulcast here in Boise on AM and FM with the same call sign, and they usually only give their FM frequency when they ID. Once in a great while they'll give their AM frequency, too. I think that's what may be happening to you.

Great to hear you're getting signals in the headphones! My first set was kind of like that.


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 Post subject: Re: new ant cont'd
PostPosted: Mon Jan 02, 2012 3:17 am 
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jeswonderin wrote:
seaview radio, 95.9 FM!

The dezzertrat is right. They simul on 960 AM.

http://www.seaviewam960.com/

73,

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 Post subject: need more input...
PostPosted: Thu Jan 05, 2012 2:59 am 
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Location: wpb fl
when simuls are broadcast, do they break the stream to enter the appropriate sid? also, don't they usually send the voice stream to the fm xmtr via land lines?

in this case, what i heard was "...fm". not even "am and fm" as many stations say.

that suggests i was hearing the voice stream intended for fm broadcast, but not necessarily hearing it FROM the fm broadcast. which in turn suggests i was picking it up via a non-airwave source.

i often listen to their am broadcast and know they always say "...am" there.

so what do you think i have?
me? i'm jeswonderin...

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 Post subject: Re: need more input...
PostPosted: Thu Jan 05, 2012 5:05 am 
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jeswonderin wrote:
when simuls are broadcast, do they break the stream to enter the appropriate sid?

Not any more. This is euphemistically called "deregulation." There's an Orlando-Tampa pairing where both ID by one or the other, can't remember which. So you hear the same callsign on two frequencies. That really threw me the first time I heard it. The old BCB, she ain't what she used to be.

73,

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PostPosted: Thu Jan 05, 2012 4:03 pm 
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There are two local AM stations that now share the same call sign. One is KIDO at 580 kHz, the other is (supposedly) KFXD at 630 kHz. Several years ago, KIDO bought KFXD, and when I started listening here, the station at 630 has been ID'ing as KIDO-630.

That's also on their website, which both stations share. When I went to the FCC database, the station at 630 is still listed as KFXD. How do they get away with that? Incidentally, they don't simulcast. 580 is news and talk, while 630 is sports.


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PostPosted: Thu Jan 05, 2012 11:15 pm 
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dezzertrat wrote:
How do they get away with that?

Back in the Cold War, FCC was diligent about station ID. Hams using mobile rigs had to notify FCC in advance of their travel plans within the U.S., with letters to each FCC Field Office in whose territory they expected to operate. Hourly broadcast station ID was rigidly enforced; I guess FCC wanted to make sure the Russian bombers got a good fix on major cities. :? There also were rules regarding joint-media ownership, and cartels of broadcast entities didn't exist. Enter deregulation, which led to syndication, automated operation (no MCs or DJs), the end of the First Class Radiotelephone License, ad nauseum. The bottom line: FCC couldn't care less. They're pre-occupied trying to sell off the white space left over from the forced transition to digital TV. Some signals you hear on AM are abominable, and it wouldn't surprise me if the stations are embarrassed to give their real call signs! BCB DXing was interesting and educational 50 years ago. I'm lucky I can hear trans-Atlantic stations, which is all that maintains my interest anymore.

73,

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