Messages

376

North American Shortwave Pirate / Re: Wolverine Radio 6950 USB 0006 UTC 01 Dec 2019

« on: December 01, 2019, 0041 UTC »

Had pretty good copy on 6950, heard some Tom Petty & The Heartbreakers with Shadow People.  Also caught parts of the SSTV, and mention of QSY'ing to 4015.

0040z 4015 USB About S8 here, was stronger on 6950 for me with about S9.  On with 'Testing 1 2 3 can Anyone hear me.'
0045z sounds like Billy Holiday.  Per shazam, 'God Bless The Child'
0053z Kitty Kallen 'My heart belongs to Daddy'

+-RH

377

Huh? / Re: GAME: [A-Z] 8 Letter Words

« on: November 30, 2019, 2048 UTC »

Transmit 

U

+-RH

378

General Radio Discussion / Re: Experts address concerns over radio frequency exposure

« on: November 30, 2019, 2044 UTC »

The system here is also on 900-something MHz. No truck is involved, meters send data on a periodic basis, there are various receiver locations, and I believe meters can relay signals from each other to reach this site.

One advantage of this is the utility can detect power outages as well as determine their scope even without calls from consumers that their lights are out.

Yes, that's exactly how these work.  They form a mesh network with the meters and pass the data along.  If you sign up with the power provider, you can get realtime usage information.  You can also get a zigbee transceiver and do it yourself.

+-RH

379

General Radio Discussion / Re: Experts address concerns over radio frequency exposure

« on: November 29, 2019, 2256 UTC »

On the other hand, because of the difficulties in delivering good quality of service to mobile devices and the subsequent delay in rollout, people are now looking at using 26/28 GHz for "fixed wireless access". Think of it as your ISP delivering high-data-rate service to your house by putting a 28 GHz, 400/1000 MHz bandwidth base station on a pole in front of your house, taking the place of Wi-fi. Then I suppose there is some risk if you are right in the path.

I've heard this as well, and may make sense in areas where it would be too costly to replace the existing telecommunications infrastructure (New York, London...)

People just willingly allowing the power company to piut these newer SMART METERS (Which are 4G cell meters) -- Thier whole house is a big cell signal bombarding them constantly!! (And making havoc on radio)

Where I live, all of the meters are 915 MHz Zigbee.  In the sticks, perhaps 3G or 4G.  The meters here constantly ping data, and are aggregated on a neighborhood level and sent back to the power company.  Every few block you will find a box with some whip antennas on it.

+-RH

380

General Radio Discussion / Re: FCC approves all digital AM

« on: November 27, 2019, 2124 UTC »

the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.

Yes but all the puppets will goto it anyway.. All the ones running IBOC will probably be the first.....


I wont listen to them if they do that so if they wanna lose listeners let them.....

The major groups had to roll out a set number of station for the initial HD rollout, and as such were contractually bound for a period of time to keep them running.  Apparently the contract has run out.  The early HD stuff was not very reliable, using industrial PC's running custom OS to generate the HD waveforms.  The newer gear is a lot more reliable, but apparently no one wants to spend the money on something that nets them no return on their investment.  The only innovations making any headway in AM these days are those that save money or power, hence why MDCL is a thing now, particularly on the 50KW flame throwers where the power savings can be very noticeable.

+-RH

381

General Radio Discussion / Re: FCC approves all digital AM

« on: November 23, 2019, 1653 UTC »

the key language here is 'voluntary'.  There is no mandate to go to digital, and in my view for any station that would be suicide.  95% of the stations out there are running at low power, messed up arrays, bad audio, etc.  They don't have the money to fix what they have and no one is going to be forming a line at ibequity's door.  I think this is the last gasp of digital on AM here.

+-RH

382

The RF Workbench / Re: A 25W experimental transmitter for medium wave (AM)

« on: November 21, 2019, 0141 UTC »

I don't have any (real) intent of that as this time.  I built it mainly to have something to test my C-QUAM exciters with, and use as an RF drive source for repairing AM transmitter modules.  Still, I do have a firebreathing box in the garage on 1750 KHz...

+-RH

383

Huh? / Re: Waffle House

« on: November 19, 2019, 2045 UTC »

I clicked and scrolled down, all I saw was links to a story from a year and a half ago.
I waited for some others to comment but I still don't get it. Must be a southern thing?

Yep. There are few in the Midwest, but the Mason-Dixon line and the Ohio River are the general boundary for them. I don't know about the Great Plains, Taco John's rules that part of country

If you drive around the South you'll occasionally run into a Tim Horton's, owned by the town's big game hunter/hunters who have more money than sense

...and Perkins.

+-RH

384

The RF Workbench / A 25W experimental transmitter for medium wave (AM)

« on: November 18, 2019, 1121 UTC »

This is something I threw together in about 5 hours.  To be honest, I'm kinda surprised it works as well as it does.  It uses a class D audio amplifier IC as the modulator, and a conventional current mode class D output stage.  The output transformer serves double duty as the tank resonator.  It is currently on 1720 KHz as thats the oscillator I had handy.  PA fets are IRF530's, drivers are TC4452's, and the modulator is a TI TPA3122.  Phase splitter is a 74LS86.  More circuit details to follow soon.



It is pretty ugly, but this was meant as a 'proof of concept' more than anything else.

+-RH

385

The RF Workbench / Re: C-QUAM stereo on PWM TX

« on: November 15, 2019, 1935 UTC »

The isb route would be cake with sdrs. Set one vrx to upper, another to lower, feed each output to a different sound card channel et voila, hfbc or ambc stereo on the cheap.

I've tried that.  The demodulation paths do not have equal delay, and you wind up with phasing artifacts that don't sound good.  Either build a plugin that does it right from IF, or forget about it.

+-RH

386

General Radio Discussion / Re: All Digital AM broadcast

« on: November 15, 2019, 1934 UTC »

In an era where the translator is more valuable than the host AM running it, I still doubt much will change.  Licensees would rather turn in there AM licenses than shell out 30-100K to go digital.  And frankly in a selfish sense, I'm OK with that.  its time we cut the dead wood and clear the band of signals that are no longer financially viable.  If you want to take over it as a full time hobby and make it something of value to the community around you, all the better...otherwise turn it off.

+-RH

387

The RF Workbench / Re: C-QUAM stereo on PWM TX

« on: November 15, 2019, 1927 UTC »

Mebbe do isb with each sb a different channel?

That's what Kahns' ISB system did, Left on lower, Right on upper.  I ultimately chose C-QUAM based on availability of receiver and transmission hardware.

What's the use having AM Stereo? Stations don't play nice love songs anymore,
like this:   https://www.youtube.com/watch?v=SV_rIY458gA   

Because I can...  Request it next time I'm on, I'll play it for you

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388

The RF Workbench / Re: C-QUAM stereo on PWM TX

« on: November 13, 2019, 2230 UTC »

From an old motorola book.



+-RH

389

The RF Workbench / Re: Pirate Radio antennas

« on: November 05, 2019, 0436 UTC »

A dipole or inverted vee are probably the most common.  There was once a joke going around that most pirate radio activity in this country occurs within 300-500 miles of Boston.  Based on this NVIS is desired, and these antenna choices seem appropriate.

+-RH

390

General Radio Discussion / Re: All Digital AM broadcast

« on: November 03, 2019, 0334 UTC »

Let PG&E run all the AM stations...   

~

What does that have to do with digital AM?

+-RH