Messages

1366

The RF Workbench / Re: Stereo to mono wiring

« on: February 01, 2014, 2246 UTC »

Your MP3 player probably won't care if its output are tied together, but if your worried about it, use a 1-10K resistor in series with each channel to sum them together.  That's all you really need.

+-RH

1367

General Radio Discussion / Re: FCC notice of unlicensed operation

« on: January 31, 2014, 0826 UTC »

ERP = (ed/7.02)^2

e= field strength in uV/M
d= distance in Meters

It is kindof a crap shoot for reasons previously mentioned; you have no idea what the measurement conditions were like.  Plus, who knows how they measured the distance to the antenna.  Generally, field strength is measured in the main lobe of antenna radiation, which would be in line with the transmit antenna.  In many cases, that's simply not possible.

+-RH

1368

North American Shortwave Pirate / Re: X-FM 6925 AM *0118 UTC 31Jan14

« on: January 31, 2014, 0151 UTC »

A vertical it is, 3KW it isn't....Wish it was.

+-RH

1369

QSLs Received / Re: Radio Ronin eQSL

« on: January 30, 2014, 1350 UTC »

Got one here too.  Thanks Henry!

+-RH

1370

Equipment / Re: Calibrating S-Meter

« on: January 29, 2014, 1547 UTC »

The only way you'll be able to calibrate it is with a signal generator.

+-RH

1371

General Radio Discussion / Re: Radio Shack Breaks Campaign In Support of New Positioning

« on: January 29, 2014, 1511 UTC »

+1, even though from what I can remember, it wasn't that good even then.

=-RH

1372

General Radio Discussion / Re: LA TV stations will share a single channel in hopes of creating new 4G spectrum

« on: January 29, 2014, 1510 UTC »

Well, I for one still watch over the air TV.  I don't watch enough TV to justify paying for cable.  Particularly in larger markets with diverse ethnic populations, over the air is still the norm.  You know the old saying "57 channels and there's nothin' on."

+-RH

1373

General Radio Discussion / Re: Shortwave pirate stations

« on: January 27, 2014, 0150 UTC »

As I understand it, most modern era pirates run close to 40M.  This is because it offers a good balance of daytime and nighttime propagation.  It also doesn't hurt that antennas in this range are less unwieldy that the lower bands.  People do operate around 20M as well, but not as many.  USB is probably the most common mode used, AM a close second.

+-RH

1374

North American Shortwave Pirate / 6924.2 KHz Radio Ronin Relay 0026z+ 1-27-2014

« on: January 27, 2014, 0029 UTC »

Hearing the sign on now.  About S8 with good 5K audio with occasional Peskies on USB.

0029 Radio Ronin ID follwed by Kenny Wayne Sheppard's "Blue On Black"
0041 Instrumental Blues piece followed by RR's "Rock Your Radio" ID
0053 RR "Ionopshere" ID followed by "Howdy Folks, and welcome to DFW"  a reference to "Big Tex" the robotic host of the Texas state fair.
0057 RR ID with email addy.  Signal starting to barber pole a bit, signal also a bit weaker, now down to S7 or so

Other projects are vying for my time, but thanks for the tunes my brother!

+-RH

1375

The RF Workbench / Re: High Efficiency Power Amplifier Based on Envelope Elimination and Restoration

« on: January 26, 2014, 2353 UTC »

The Kahn method is how high power shortwave transmitters generate SSB with good efficiency.  I imagine this paper was targeting cell phone PA's to extend battery life.

+-RH

1376

General Radio Discussion / Re: FCC notice of unlicensed operation

« on: January 26, 2014, 2350 UTC »

Based on the number in the report, he was running about 355W ERP.  I personally know a few people who have been busted running far less

+-RH

1377

The RF Workbench / Re: So...what can a person do with 2 or 4: WL23791/TH150

« on: January 24, 2014, 0131 UTC »

My point was that, series modulation does work, best at low power levels because of the inefficiency involved.  If you were going to do high level PWM ala Harris's MW-5, et all, thats a different story.  High level PWM does work very well, and even today's solid state MW and SW transmitters under 6KW use this principle.  To my knowledge, the only domestic manufacturer of high level tube PWM transmitters is continental electronics.  They have a 50KW "Solid state modulator" which is essentially 48 750V power supplies individually series modulated with PWM and wired in series to get 10KV average B+ for the final tube.  The benefit; no modulator tubes, high efficiency, and lower operation costs.  The custom plate transformer which rolls on railroad track by the way, must be a pricy one.  Never mind the fiber optic drive system.

+-RH

1378

General Radio Discussion / Re: homeland security

« on: January 24, 2014, 0122 UTC »

I'm not sure if they would be trunked or not.  P25 is the norm now.  I worked for a TV station at one point that bought a P25 capable scanner for news purposes.  All the stuff they wanted to hear was encrypted   This is also becoming the norm for EMS, fire, and police, at least in the areas I've surveyed.

Good luck,

+-RH


...The 'Old Professor says "Your 9-11 tax dollars at work!"

1379

General Radio Discussion / Re: homeland security

« on: January 23, 2014, 0805 UTC »

My guess is your location will likely influence your likelyhood of hearing something.  I would guess that anything they use will be APCO-25 with some form of encryption.

+-RH

1380

General Radio Discussion / Re: Hudson County TIS 1710 Going to 100 Watts

« on: January 22, 2014, 1806 UTC »

One other thing I forgot to mention, there are a lot of people out there that never report anything.  Even if you give out an email or postal address, I think a lot of people just grin, listen to the music, and move on.  Only the diehards send in reports and such.  The fact that I could be on the air, and call up my cousin several states away and say "go to you car and tell me what you got on 1710" has some merit.

+-RH