messin with LW again

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majoco

majoco

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Most of the beacons I hear have 1kHz modulation so if I listen on AM, that is the frequency I hear. If I am listening to a CW signal and tweak the BFO for my 'preferred' tone, it is usually about 750Hz +/-. Unfortunately an AM signal is liable to be swamped with lightning crashes and locally generated interference, mainly due to of course "Amplitude" modulation. If I go to the G303 SDR then I can switch to CW and actually just select one sideband in the filter. If the mod freq is 1kHz, then I can easily pick the upper sideband and treat it as a CW signal. The 'BFO' then makes this into the 750Hz tone - although I can adjust this in the settings. Unfortunately a 'normal' CW receiver has a problem with MCW if you cannot get the bandwidth right down - you get an audio tone from the carrier and a different one (or two?) from the modulation. You can get rid of the carrier tone by retuning but the best way is to tweak the BFO to get zero beat - retuning to get rid of the carrier only puts the signal out of the passband.

Here's the picture for AM...

WanganuiNDBAM.jpg

You can see the carrier and the two sidebands with the carrier freq 382kHz.

..and for CW on the carrier only....

WanganuiNDBCWcarrier.jpg

In theory all I should hear is a continuous tone - in fact there is 'negative' modulation! The carrier level drops with modulation - usually a sign of power supply poor regulation.

..and then for selecting the USB on CW...

WanganuiNDBCWUSB.jpg


Here I have selected the USB by detuning - the carrier and LSB is inaudible as it is outside the 580Hz bandwidth.
 
corbintechboy

corbintechboy

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ridgescan said:
You really should log it in this site as you would be their 1st Kentucky log there and for you that is a 2115 mile LW DX!! Very impressive:)
RNA > signals
Click to expand...

I have tried to figure out that site...

I would log it there but have no clue howto use it lol.

I received that signal very weak. It was buried in noise and barely audible at all. I was proud and removed my headphones and let my wife hear it, she asked if she should be impressed, I told her "yep" and she said "very good" lol.
 
ridgescan

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ok what I need to do is stay the heck off LW at bedside! Again, I was in bed ready to fall asleep but Noooooo, I hadda cruise the low one. Caught another Canadian beauty:) "NY" out of B.C. at 900 miles and 500 watts. This time I stuffed you into a set of good old Pioneer headphones so you can get a better listen PLUS, for the 1st part of the video I had it tuned to 351khzlsb for a stronger tone. Then at 1:18 I tuned it to its proper 350khz frequency and.. as you can hear, yet another Canadian NDB with that super soft tone! This will be my 3rd NDB DX with that same exact tone. Then at 2:24 I stuffed you back into the phones for one last listen:D
YouTube - ‪LW Beacon-"NY" Enderby, B.C.‬‏
 
R

Rector

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Although I've been in N America ten years I've only just returned to DXing and need to culturally adjust! Growing up in the UK where LW was and is a broadcast band (with huge power transmitters) I must now listen out for... other stuff. But fear not. I have a giant loop antenna in build simply for night time nostalgia...
 
mmckenna

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Cool, I'm getting ENZ also from my receiver in Santa Cruz. AOR2300 with an end fed wire on top of a building. It's coming in pretty strong.

RYN on 338 out of Tuscon, AZ, but it's partly covered by PBT out of Redbluff CA.

BO on 359 out of Boise Idaho is there also. 547 mile path.

ENS on 400 out of Ensenada Mexico. 470 mile path.

Probably not impressive, but I'm just starting to play around with LW.
 
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ridgescan

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Nice MC:) and we're sorta neighbors too. the Canadian ones are booming too. Try 385kHz WL Williams Lake, BC and also 403mHz NY Enderby, BC
For me they are 900-some miles..for you those are over 1000 miles:)
 
mmckenna

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On 385KHz all I get is the beacon at Monterey airport. It's direct line of site to where the antenna is, probably only 25 miles across the bay, so no luck.
403KHz, all I'm gettingis Montague CA. (MOG)

My set up is not very good for LW, MW or SW. The receiver is located at work on top of a building at one of my repeater sites. I have a 55 foot tower with and end fed running across the roof, from about 15 feet up the tower. There is cellular, VHF and 800MHz stuff on the tower.. Just adjacent to the antennas are a bunch of air handlers. I'm actually surprised it works as well as it does. I'd like to try reorienting the antenna, or lengthening it. Right now it's only 60 feet long.
 
ridgescan

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mmckenna said:
On 385KHz all I get is the beacon at Monterey airport. It's direct line of site to where the antenna is, probably only 25 miles across the bay, so no luck.
403KHz, all I'm gettingis Montague CA. (MOG)

My set up is not very good for LW, MW or SW. The receiver is located at work on top of a building at one of my repeater sites. I have a 55 foot tower with and end fed running across the roof, from about 15 feet up the tower. There is cellular, VHF and 800MHz stuff on the tower.. Just adjacent to the antennas are a bunch of air handlers. I'm actually surprised it works as well as it does. I'd like to try reorienting the antenna, or lengthening it. Right now it's only 60 feet long.
Click to expand...
My mistake on 403-it's 350kHz but when I jumped back in there to look up the frequency I read the wrong one. Anyways you're getting what I'm getting here so your setup aint bad. Are you higher up altitude wise also? I gotta get down there I miss old Santa Cruz. I used to hit Hwy 1 with Rosie in my old Camaro and do the coast tour:)
 
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