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Messages - Kage

Pages: [1] 2 3 ... 8
1
OP definitely doesn't want to investigate the chaos of my homebrew gear without their head exploding lol, but I'm a hobbyist so that's another story.

I want to feel bad for Stretchyman but this could be a learning moment here. Honestly with my own designs I wish I had someone scrutinize my work for free like this, wrong or right, it's still useful to go over things again and analyze. Part of the design process, and why version 2, 3 and so on of a product come to exist.

I do understand just enough about class E/D transmitters and power transients, gate protection, switch-on timing/ramp-up protection (like the big class E ham stuff) and so on to follow along with that long document. So maybe the best idea here is to show how to reproduce the problem easily in the lab, then find a way to quickly fix and put an end to it like the document suggests if this can be reproduced in a similar lab utilizing compatible but other equipment to rule out external faults?
Here I thought my worst fear was switching on a PA FET before the PLL/DSS got running and a pull down resistor on the gate was enough. Ugh, problems show up everywhere even in the most well planned out designs. Then when you think all is working flawlessly something causes a parasitic oscillation where you didn't expect and magic smoke is filling the room.

You know you two might be at odds with one another over this but maybe it would be beneficial to the community at large to work with one another. You're obviously both quite educated by the posts I read like this. Maybe put the egos aside and work together?

2
Equipment / Re: 65 turns loop for vlf reception
« on: May 26, 2020, 1720 UTC »
Just off the top of my head but a 5:1 or 6:1 transformer should get you in the ballpark. 5^2=25*50ohm=1250ohm, or 6^2=36*50=1800ohm. You'd need to pick a toroid core mix that is effective at those low frequencies. Generic ferrite types might be fine or even an old AM radio loopstick ferrite. Maybe something like 4 turns primary and 20 or 24 turns secondary. The ratio is squared and primary turns might require some experimenting.

The other way to go about it is to use the loop itself for the transformation using a few turns around it as a sense wire, then a variable capacitor to resonate the 65 turns. I believe this is far more common, or at least how I built a loop for MW ages ago. It will not be wideband though.

I'm curious how you came to the 1300ohm impedance value? If I remember right loops are often much lower impedance only needing an autotransformer voltage balun or a transformation of 50 to around 450ohms?

Wouldn't mind building myself one again soon.

3
10/11 meters / Re: What the hell is this noise?
« on: May 23, 2020, 1601 UTC »
Maybe its a robot vacuum, it may not be finished in getting set up, so it is sending out a signal. There are alot of bargan no name vacuums made in china. It would be a surprise to me that they are working that low of a freq. From listening to sound, its more like an rc car or a door opener.
That would be funny if that is what it was.

Thankfully whatever was causing it mysteriously vanished the other day after I got fed up and keyed high power of my own over the same frequency a few times. The annoyance hasn't been back since (crossing fingers)  ;D

4
10/11 meters / Re: What the hell is this noise?
« on: May 15, 2020, 1728 UTC »
Oooh just read this..
https://www.soinc.org/sites/default/files/uploaded_files/SumoBotsFAQs.pdf

"27 MHz has 6 major sub-frequencies. There are two standard ways to refer to these sub-frequencies:either by their frequency number or by their channel number. The subfrequencies for 27 MHz areChannel 1 (26.995 MHz), Channel 2 (27.045 MHz), Channel 3 (27.095 MHz), Channel 4 (27.145 MHz),Channel 5 (27.195 MHz), and Channel 6 (27.255 MHz). The FCC has recently added an additional 6sub-frequencies (channels 7 - 12). Channels 7 to 12 are really intermediate channels between 1 - 6 (forexample, channel 7 uses a frequency between the frequencies of channels 1 and 2). Only the mostmodern transmitters/receivers can use those channels without causing interference"

So maybe it really is some RC device, but damn does it splatter a few channels up and down CB ch16 >:(

5
10/11 meters / Re: What the hell is this noise?
« on: May 15, 2020, 1722 UTC »
no, i know that sound, lol. its a classic rc car remote, lol. alot of the rc cars from the late 90s and older operated within the 11 meter band.

funny enough, i still hear that classic sound sometimes, but not constantly 24/7
That's exactly what I thought it was at first and the sound is just like that of my old RC 27MHz cars, like some kid threw his remote into a toy box left on and some other toy is continuously pressing down a button.
The closest frequency is 27.145MHz for RC cars but this signal is on 27.150MHz. I guess it's close enough that it could be a remote, but the signal is quite strong around here and it seems to be coupling into nearby power lines, though that could be coincidence.

For fun I keyed up my radio a few times on the frequency just to see if it would have any effect. Maybe whatever device is causing this noise gets disrupted by my keyups :P
Makes me wonder if someone modified an RC car to control something else around their house and added on an antenna, or if it really is some chinesium junk device left turned on.

6
General Radio Discussion / Re: End Of Show Songs?
« on: May 14, 2020, 2237 UTC »
Roaring 60s - We love the pirates. Ended just about every show with that but usually not the last part of the song, fade out then off goes the TX power.

7
Equipment / Re: fun toys (digital multimeters/oscilloscopes)
« on: May 14, 2020, 2138 UTC »
For around $60 you can buy a Hantek 6022BE dual channel 20MHz DSO (oscilloscope) with BNC probes that will far outperform the one you linked. There are other models that can easily get to 100MHz or more for a little more cash.

I use mine with the free openhantek software (RichardK version) for Windows or Linux that is almost identical to the professional scope software instead of the software it came with which is a little clunky, and there are quite a few apps for android to connect the scope up to a tablet computer with a USB OTG adapter plug which is ridiculously useful when testing things "on site".

After using DSOs for a while I don't see myself using analog oscopes anytime soon unless I'm worried about testing high voltage. Anyone here into building electronics should have one of these on their workbench given how cheap they can be had for.

That multimeter looks suspiciously like this one...  :o
https://www.youtube.com/watch?v=1k04p4UgS6Y

8
Sonicart anyone? I still enjoy using Sonicart 2.2. It's old as hell, circa 2000 lol, but it works, and it works really well if you just need a virtual DJ to take over for a bit. It also has sonienc and sonipack and some other tools to slip in and time promos and IDs. Best of all it all works fine in Wine on Linux.

I mostly use Sonicart itself just as a media player because the artificial selective fade between songs is damn near perfection compared to modern programs I have tried. If I load it up with a track list and let it run it just works and does an acceptable job at transitions and mixing up or cross fades how it does them by analyzing song endings first before moving on. It's real long in the tooth now. Glad this thread exists so I can try and learn some new tools. I tried Rivendell for a bit. It was broken but probably from my lack of understanding it, simplistic usage I am told, but hell if I could wrap my head around it. I tried a bunch of automation all-in-ones on Windows and they were horrible. Oddly Rivendell at least worked right on Linux, but the process of forcefully categorizing music and data, and worse yet requiring a database and software for that too made it far too complex for my liking for simple show production.


I preferred simple track/cart emulation software like Sonicart. It just worked, had great transitions and keyboard access for instant play or auto-cue and would time it all out well.
Only issue the author seems to be missing.

I guess my main thing is live production. I get bored like anyone else listening to radio shows that are pre-programmed with a voice. Real DJs spin records hehe. Not sure we should be mimicking the mainstream crap.

9
10/11 meters / What the hell is this noise?
« on: May 12, 2020, 1750 UTC »
https://www.youtube.com/watch?v=6BOi1QykSnY

I am pretty ticked right now. Been investing a lot of time in building a new EFHW monoband antenna now that I got some type 6 yellow toroids to play with. Literally the same day I received them in the mail and started experimenting I turned on the radio only after a day of having it off and now this plagues multiple channels.
Like many I monitor 27.185 so I first noticed it there, then channel switched around to find the culprit, happens to be ch16, but it's actually a zero, 27.150MHz.
Looked up anything on the frequency, zilch. Harmonics are not alive. It's specifically this frequency.

So after a few days of this now I walked around, noticed it was covering the whole damn area. Took my DX398 and biked around in anger and narrowed it down to a fenced in house 1/8 mile away.

I stood outside on bike with my radio and monitored it to make sure, yup, it's this house.


WTF kind of appliance would cause that noise at that great of a distance?
The tone does not change. It's a constant ... that. At first I thought it was some kids RC car remote stuck on ON, because it sounds like it. This thing is covering 1/8-1/4 or more mile of reception and I don't know what to do except pray they turn off whatever it is!


I don't make this much interference as a pirate radio operator lol. This crap has to be some chinesium flame thrower over powerlines or something. I had a hell of a time narrowing it down to the house because the power lines were carrying it. WTF?

10
MW Loggings / Re: Hudson County PSA 1710 AM 0059 UTC 18 Apr 2020
« on: April 19, 2020, 2346 UTC »
After doing a quick search I found I'm not the only one who noticed the signal this far away..
https://fmradiodx.wordpress.com/2019/04/16/only-u-s-am-signal-on-1710-am-received-in-virginia/

I'm calling shenanigans on this station. No way 10 watts is getting out that well, someone had to have bumped the output power button way up.

11
MW Loggings / Re: Hudson County PSA 1710 AM 0059 UTC 18 Apr 2020
« on: April 19, 2020, 2342 UTC »
How is this station so strong suddenly?
I never noticed anything on 1710kHz for years except the occasional pirate or local talking house Christmas music show. Last night I tuned to that frequency again as I normally flip past it and heard this transmission. At times the signal was strong enough to blank out all static and after using google earth I calculated that the station is some 800 miles away!
This is going to make listening to pirates on this frequency a bust.
I can't imagine a 10 watt TIS could get a signal out this well legally unless they were allowed a massive power increase.
Oh and yeah.. I washed my hands after hearing the recorded voice say to do so every minute. ::)

12
Longwave Loggings / Re: Radio Algeria Chaine 3 - 252 kHz
« on: March 08, 2020, 1419 UTC »
Almost 99% sure this is what I listened to last night and if so then this will be my first AM longwave broadcast catch.

I usually give my ATS909 a quick dial through LW and hit a solid signal on 252kHz. At first I thought it was a harmonic but it zeroed on
that frequency instead of 250kHz or 255kHz. Did a quick check of SW and MW to see if I was hearing something else and confirmed
that it was only found on LW. I didn't make out the language at first but now I know.

First longwave AM DX for me! Yippy. Only took 20 years ;D
Not bad for being in the midwest of the US. This all off of my 130' inverted L and a bunch of random ground radials that I normally use for "other purposes".
It sadly faded out slowly after hearing it but seemed to fade back in half an hour later. Interesting how long the fades take on LW.

13
Equipment / Re: Spitfire Am transmitter
« on: March 04, 2020, 1808 UTC »
All of this music, for me, was listened to via AM radio. During the majority of the 70's I was in an area that wasn't served by any listenable FM station, so everything was AM Top 40 from local and at night, distant stations.  I have a certain affinity for the sound of AM radio. That's it. Carole King or Jethro Tull hit music sounds weird in pristine, clear, digital audio. I know it from AM. And I like it that way.
There is a certain sound to AM too. Even if you listen to the highest quality through a modulation monitor it still has a different quality to it than FM because of the methods used for broadcast processing.

That big and loud sound coming from either rack processing or StereoTool, once setup properly gives a punch that you just don't hear on FM and sometimes even further removed from the actual music source. Musicians hate this because their music doesn't sound the same on radio but to the listener it can be enjoyable because of the exact same reason.
Then there is the fact that some of the early rock music was actually mixed down in the studio with AM radio listeners in mind, so not only did they aim for HIFI listeners they also aimed for a sound that would suit peoples car and kitchen radios of the time.

I like to keep it simple and use an AGC to three band audio downward-expander/compressor into a mix of limiting and clipping. Finally with proper audio bandwidth brickwalling and compensation it can sound exactly like the big market stations of the 70s and 80s pushing maximum modulation or even into the positive with asymmetrical clipping for that huge sound.
Of course I like all of this to be analog and rolled my own gear to do so, but modern software replacements can achieve the same, or better. I find it best to not over complicate it and keep the audio path cleaner so not be fatiguing but loud enough to punch through the static and noise. Anything more than this might give you that giant market sound but it becomes overkill with a dozen pieces of gear or plugins running.

With mediumwave all your investment of time and money is going to be in audio and antenna anyway. Transmitters for the MW band are so cheap to design and even those Part 15 transmitters can get a huge improvement out of the two being their best.

Besides all of that, there is nothing wrong with enjoying nostalgic sounds. Get the most out of the medium and have the most fun with it!

14
10/11 meters / Re: Man without a life....
« on: February 15, 2020, 1844 UTC »
And here I am running clean power with harmonics well below the legal levels, outboard audio pushing the modulation stage to 100% positive and a little less negative so I can actually get the most power out of those 4 watts and Anytone "Smart CB" and voice bandwidth instead of splattering on my neighbors channel. In fact I've been told to actually turn my modulation down by a local because my clean signal was louder than the superbowl goofballs even though I was hitting the scope at a little under 100% pos and 95% neg on a stock radio using proper direct AM processing with slight assym filtered clipping.
Properly used modulation rivals that of the splatter boxes most people hear, think about that. Your distorted voice on every damn channel with a kilowatt isn't hardly working as well as a few watts with nice audio processing and voice compression and EQing a basic mic into a A99 or 1/4 GP.

I can't understand people who think the more noise they make the more will listen. All they do is yap at themselves because the rest of us are tuned out on purpose and frustrated that they bleed over on clear channels. They aren't sounding cool and the only good thing that swing is doing is hopefully stressing their PA until something goes pop.

Even us pirates understand good clean audio with lower power is far better than high power through a distorted mess of harmonics and spurs and shit modulation. All these people do is ruin radio for the rest of us and gives amateur ops an excuse to call it the chicken band for good reason.
I'd be okay with the idea of new people not knowing better and willing to learn, but a lot of these CB ops I've found are so hardheaded they refuse to learn how to get a clean signal. It's almost like they prefer being willfully ignorant or want to piss off people.

Luckily there are some really good 11m users out there, and they stick to the upper SSB channels or antiquated AM 23ch. channels of times past to strike up a good conversation.

15
10/11 meters / Re: I would like to build a beacon on 11 meters
« on: January 07, 2020, 2331 UTC »
I don't condone jamming but if you want to tick off a local yahoo that gives you endless crap on air you can build a few milliwatt single channel solar powered transmitter and toss it up a tree near by so it only messes with them and has a range of a few houses or so.

If you replace the crystal or parallel connect it to a piezoelectric speaker they can become wideband RF jammers around the frequency, did that as a kid but not absolutely sure if that's how I wired it. The piezo acts like a crazy unstable quartz crystal making a ton of AM noise.

Can purchase those solar lights for a dollar and series wire a few to drive a single transistor crystal oscillator, and at night they will run on the batteries they came with. Real cheap and effective. Makes you a beacon and for the a-hole a localized jammer.

If you want to make a noise maker out of it you can wire one of those LEDs that change colors slowly when powered and paint the bulb black so no one sees it. The tiny circuit in the LED bulb throws off a bunch of weird groaning PWM sounding stuff when wired in series with other circuits. I'd bet even a self powered beeper or buzzer if mechanically dampened so no one hears it with their ears would create AM if wired the same way into an RF oscillator and take almost no power to run for hours or days. Maybe even a self blinking LED would work this way. Experimenting being all part of the fun ;D

Wouldn't be any harder to build than a bug, but legality is another story and you certainly don't want a bomb squad to come out from a neighbor that finds it thinking it's dangerous. Just make sure it's made of junk because someone will find it and inevitably end up in the trash, or posted on reddit asking people what it is.

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