Messages

301

North American Shortwave Pirate / Re: 6935.0 u 0119z 7-21-2010 Playing Asian-flavor music

« on: July 21, 2010, 0139 UTC »

Good signal, good audio...  sounds Indian to me.  S-9 

Worked with Indians and Asian @ Cisco ... I gotta go with Far-East ...

302

North American Shortwave Pirate / 6935.0 u 0119z .. 0148z 7-21-2010 Playing Asian-flavor music

« on: July 21, 2010, 0120 UTC »

More as available

VERY good sounding ... good lows ... S6.5 in Texas ATTM

0123z Okay the speech I just heard was not Indian ... more Vietnamese or

303

North American Shortwave Pirate / 6925.00u now 0110z 7-21-2010

« on: July 21, 2010, 0111 UTC »

0110z 6925.0u now ... think its Outhouse radio - heard what I thought was an ID a little bit ago ...

304

Other / Re: RF Noise Identification

« on: July 20, 2010, 1521 UTC »

The signal is continuous with no breaks. It does exhibit fading as you mentioned as well as a regular 'beat'

Since you mentioned 'data stream' here is the closest example I can find:

MOTOTRBO™ Professional Digital Two-Way Radio System:
http://business.motorola.com/mototrbo/mototrbo.html

And here is unencoded audio of MOTOTRBO:
http://www.nonstopsystems.com/radio/sounds/radio-mototrbo-undecoded.wav

They sound remarkably similar don't they?

Reason being, I conjecture, is, continuously sent 'data packets' or streams of this nature are usually encoded in fixed-length packets, and these repetitious packets are usually encoded with a 'sync pattern' to allow initial synchronization to the incoming bit stream ... then additional processing takes place to begin to read the series of bits ... also encoded (depending on the purpose or function of the data) are addresses,  system overhead info (like system ID, maybe a protocol to observe when responding, time/date etc) as well as situation-specific data (like data payload: something that means something to the receiving station) ... as well as some sort of FEC (forward error correction - similar in concept to the Reed-Solomon encoding on a CD for instance) ... I say this, b/c, in past years I made an intensive study of the Moto 3600 baud GMSK-modulated trunking control channel format ... and it too corporates these features/facets I mention above ... plus one or two more features - like a block parity code (used for verifying the FEC corrections - they could be in error!)

305

Equipment / Re: Does AM loopstick orientation matter? Can the phase be reversed?

« on: July 20, 2010, 1506 UTC »

I've tried that trick of stacking two portables together to sharpen the null.  Works fairly well on the smaller portable, but does nothing for the larger Magnavox and Sony portables.  But it seems to indicate that something like the DX Tools Quantum Stick or comparable homebrewed doodad will help.

I've placed tuned ferrite loopsticks (4" loop stick with the 'factory' coil tuned with the little plastic Japanese, now Chinese, made tuning caps) end-to-end with an AM radio to squeeze out a little more SNR (signal to noise ratio) on a weak AM broadcast signal before like I think many of the posters on the board may have done at one time or another ... the experiment in this video was to show that the RF wave does show signal 'phase' (and apparently maintains it during RF downconversion through mixers and IF stages and even down to audio bandwidth stages) with respect to an independent or external reference signal ...

From this experiment it can also be concluded that: the carrier originally sent with the modulation on an AM signal is required for proper in-phase demodulation ... not just any-old 'carrier' can be reinserted, and, it also underscores the need for some sort of 'reference' to be transmitted for proper phase of the 'demodulating' carrier in the final (last) detector (product detector for SSB or 'envelope detector' for AM), be it a full strength carrier or a reduced-amplitude carrier, which allows AMS (AM-synchronous) to be used to 'demodulate' the signal in-phase with the original modulated carrier (esp with considering ionospheric paths, phase changes st al) that exists in some form (be it the final high-level plate or collector or Drain modulated stage or further back in the transmitter in the case of low-level modulated AM or SSB or DSB/Suppressed carrier) in/at the originating transmitter. Just something I have thought about in the past ... Of course, with DRM/digital radio this phase thing (the phase relationship between the modulating program audio and the modulated carrier) 'goes away' ...

Sorry for being so long-winded on an such an esoteric subject!

306

North American Shortwave Pirate / 6930u WEAK Radio 0424z 7-20-2010

« on: July 20, 2010, 0425 UTC »

More as available

0431 ID: "WEAK Radio"

0440z Gotta go WEAK, thanks for the pgm ...

307

General Radio Discussion / Re: Bye-Bye Batteries: Radio Waves as a Low-Power Source

« on: July 20, 2010, 0416 UTC »

I think that the antenna would not be as much of a problem as solar panels. Stealth wire is readily available that blends in very well with the background.

The advantage of this method would be that the beacon could be completely hidden, unlike one that relies on solar power.

Antenna ... what provisions are you going to make for an antenna - a 1/2 Lambda radiator of some sort; even loaded shorty can require 1/10 Lamda?

(Isotropic point-source radiators have not been perfected yet ...)

How big are your SPs? Little 2" x 3" panels for recharging those outdoor nitelights can supply 50 mW (2.5v x 20 mA) easily ...
 

308

General Radio Discussion / Re: Bye-Bye Batteries: Radio Waves as a Low-Power Source

« on: July 20, 2010, 0330 UTC »

The advantage of this method would be that the beacon could be completely hidden, unlike one that relies on solar power.

Antenna ... what provisions are you going to make for an antenna - a 1/2 Lambda radiator of some sort; even loaded shorty can require 1/10 Lamda?

(Isotropic point-source radiators have not been perfected yet ...)

309

North American Shortwave Pirate / 6924.92L->u 0319z .. >0438z WLDJ 7-20-2010

« on: July 20, 2010, 0320 UTC »

Also a carrier still present per prev post

And yes, you can still hear some of WLDJ on the upper sideband ...

This is where listening DSB/ISB is interesting; normally ISB with the WR-G303e results in WLDJ coming out the right CH spkr louder ... not it's reveresed and the left CH spkr is louder (not to mention the spectrum scope shows much more LSB than USB ATTM)

0333z Pgm continues ... peaks to S6, QRN increasing, AM carrier still present at 6924.6 or so ...

0339z WLDJ LSB the last few minutes competing with A) a carrier B) a QPSK31-like signal (too slow for RTTY, and has just a slight freq shift to it)

0345z Just to note: WLDJ's audio has become distorted; sounds like PA bias was turned down on the final PA devices (best way to describe it) also, signal considerably weaker ... 6146s or 6JS6s give up the ghost? 10V 20W Zener in the Cathode circuit cook?

0353z Carrier and QPSK31-like sig have been gone for sev min now ...

0359z Haven't heard "Fish Heads- Fish Heads - pretty little fish heads" in quite awhile ...

0412z Audio quality picked up! Much better!! Ahhh ...the B-52s ... love the gal that sings in that band ...

0417z Back to distorted ... TX engineer needs a station monitor (O-scope) to watch for flat-topping ...

0420z Oh yeah, WLDJ is now USB ... and now back to lower ... and upper!

0436z Audio has been better for some number of minutes now too ... MUCH easier to listen to!

310

North American Shortwave Pirate / 6924.6am UNID <0301z 7-20-2010

« on: July 20, 2010, 0303 UTC »

Been going for awhile

Carrier zero beats on/pretty close to 6924.6 kHz

0303z now off-air

0306z Just noticed, carrier is back ... with bits of audio coming through now and then ...

0310z Better zero beat using 6924.59 kHz ... AM Sync Demod working now (must be tuned close to work) ...

0322z There may be two carriers present down around 6924.6 kHz, one is even weaker than the other but there is a distinctive beat that is not the result of just a single carrier ...

0348z Just noticed carrier is off-air

311

North American Shortwave Pirate / Re: Radio Ga-Ga 6925U

« on: July 20, 2010, 0219 UTC »

Good signal there for the last few minutes; peaks to S5 with QRN now increasing

312

North American Shortwave Pirate / 6925u Lex: RGG 0203z 7-20-2010 (was competing with WLDJ)

« on: July 20, 2010, 0208 UTC »

More as available

6925.00 kHz on the previous UNID that Lex IDs as Radio GaGa

6924.98 a little better sound from the G303e (which is about 10 Hz off as checked at 10 MHz)

313

North American Shortwave Pirate / 6924.9 L 0201z .. 0209z WLDJ 7-20-2010

« on: July 20, 2010, 0207 UTC »

WLDJ using LSB so the station on USB won't interfere ...

0209z WLDJ now appears off

314

North American Shortwave Pirate / 6925u 0136z .. 0150z WLDJ 7-20-2010

« on: July 20, 2010, 0137 UTC »

Just started ...

6924.92 kHz

0136z - 0139z "How do fix a broken heart"

0140z - 0143z "Baby if you want my love you better take me home"

0143z Peaks to S6, negligible QRN so far

0150z ID: "You're listening to WLDJ ..." and off ...

315

Other / Ocean Motion - HF RADAR

« on: July 20, 2010, 0122 UTC »

While surfing for other info, came across a little more info on:

Ocean Motion - High Frequency Radar: http://oceanmotion.org/html/gatheringdata/hfradar.htm

HF Radar Derived Surface Current Data:

North America - http://cordc.ucsd.edu/projects/mapping/maps/

Gulf of Mexico - http://www.cengoos.org/