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Messages - OgreVorbis

Pages: [1] 2 3 ... 8
1
The RF Workbench / Re: Transmitter set up
« on: January 16, 2020, 0900 UTC »
Soundboard = mixer, ok I get it now...

Just record and process everything on a PC. Playback as an MP3 or whatever. Simple cheap. No need for any expensive hardware..

Str.

Yeah, you could just use stereotool, but I think you still need at least a cheap mixer to connect your mic. The kind of mics you can connect directly to a PC sound card are not the best and then you can't fade it in or talk over.

2
The RF Workbench / Re: Transmitter set up
« on: January 15, 2020, 0509 UTC »
Great advice. Yes as a ham myself that would be frowned upon for sure. Other than the transmitter and antenna. What equipment is used as far as an interface to get the sound audio into the receiver and also what would be used for the voice. This may sound a bit silly, but I would imagine theres more to it than keying down a microphone while playing music through a speaker. I used the term soundboard because it was the first thing to come to mind. Thanks for all the feedback.

A cheap mixer like a behringer and a mic pre-amp (some come with compressor, limiter and de-esser built in). These can be found at a good price from sweetwater. You also need XLR cables and maybe an XLR to 3.5mm so you can plug in a comp to the mixer for the audio. The third and final thing is the audio processor. That's pretty much all you need. The most expensive part will be the audio processor. The cheapest way if you have some technical skills is the ADAU1701. On aliexpress, you can find modules with this DSP installed. Make sure you get the programming board also. You don't need to know how to program. You can use SigmaDSP which is an audio processing program that uses visual drag and drop style processing blocks. Takes a bit of work, but it's not very hard to learn. If you want to go the easier route, then you can probably find an old optimod AM processor on ebay (but it takes some time to find a reasonable deal) and it's going to cost a bit more money. The SW200 is pretty good too. To start out, you don't even really NEED the audio processor. Just build a low pass filter for 5 kHz or whatever you want. You'll need to get some XLR cables that you can rip apart and put some resistors to combine the stereo output into mono. On this same board, you can make a little low pass filter (just need some caps, resistors and a copper clad board). Look up stereo to mono audio schematic and low pass filter schematics (there's probably a calculator online somewhere). Now you just combine that on one small copper clad PCB. Then that leads directly into the transmitter. If you use an audio processor, then you won't need the filter part, but you may still need the stereo to mono conversion.

3
SDR - Software Defined Radio / Re: Overview list KIWI WebRX's
« on: January 15, 2020, 0445 UTC »
Thank you very much  :)

4
SDR - Software Defined Radio / Re: SDR.HU
« on: January 15, 2020, 0438 UTC »
This is very annoying. Luckily, I've got some of the SDR's bookmarked and they still work fine. So if someone had the links to all of them in a list, then they could still listen.
I only have a couple bookmarked though :(

I wonder why they did this? This is going to greatly effect their popularity as a lot of SWLers are not hams. Seems like a bad choice to me.

EDIT: Well, I spoke too soon. Looks like cool AM radio posted a list: https://www.hfunderground.com/board/index.php/topic,62141.0.html

5
Propagation / Poor conditions (noob)
« on: January 13, 2020, 0402 UTC »
Hey,

I'm not a noob to radio, but propagation (other than the more obvious non-planetary/solar noise stuff) has not been something I really understand very well. I do understand the solar cycles to some extent, but I am curious about the more frequent changes in propagation that can be seen on a daily or weekly basis. What is the biggest determining factor in that?

I noticed the last couple days that the propagation has been some of the worst I've seen since I started listening about a year and a half ago. What is causing this and when is it likely to clear up?

6
General Radio Discussion / Re: Pirate Act Passes Senate
« on: January 11, 2020, 0632 UTC »
I find it odd that they chose 535 to 1705 kHz. Kinda strange. I wonder why they didn't use the typical 530 - 1710. It looks like the FM pirates are screwed though. I wonder what would happen if someone chose 87.69  :P

I also find it interesting that they are so concerned with pirate radio that they feel the need to enact more laws. It should be the least of their concerns now. The internet with its freedom of communication is much more damaging to them. Just some people playing unusual music on the radio shouldn't concern them. Almost no pirates are political, so... But they are the government afterall. Just control as much as possible is their motto.

7
General Radio Discussion / Re: WQFG689 antenna
« on: December 20, 2019, 2115 UTC »
Possible antenna:

https://www.google.com/maps/@40.7398821,-74.0570985,3a,15y,305.61h,100.9t/data=!3m6!1e1!3m4!1sdXpMIjD5PMWCaRM-s-EIHA!2e0!7i16384!8i8192

Can't believe you found that. It looks like a valcom antenna: https://www.valcommfg.ca/v-147-cl2-th
I wonder what makes this one better than the other TISs. I would expect them to all use valcoms (maybe not)?

One note for TIS hunters: The FCC database only has some of the TIS stations listed. Those operated by the federal government are *not* listed.   These include the Flight 93 Memorial in PA, and the Springfield MA Armory on 1710 kHz, as well as many other stations on other frequencies, such as those in national parks, on military bases, etc.

I filed a FOIA request with the government to get information about these "missing" TIS stations. The information is incorporated into my DX ToolBox program for Windows and macOS. AFAIK it's the only source for these stations. You can get a copy of DX ToolBox here: https://www.blackcatsystems.com/software/ham-shortwave-radio-propagation-software.html

Nice work on that program. I just downloaded it and tried it for a few minutes. I found it saying I lack an internet connection despite it seeming to work properly and download databases.


8
General Radio Discussion / WQFG689 antenna
« on: December 20, 2019, 0847 UTC »
I've been wondering what the antenna for WQFG689 looks like. Does anyone have a picture or has seen it before? (I did try looking it up and I was unable to find anything on google.)

I find it surprising the coverage that it has. No other TIS covers so much. It goes hundreds of miles and I never hear any other TIS on 1710. I assume they are limited to the usual 10W of power, so their antenna must be really good.

9
The RF Workbench / Re: AD9833_SPI
« on: December 08, 2019, 2238 UTC »
...see my last post.

BTW, why did you choose the AD9833? I've never really heard of it. Is it any better than the AD9850 modules?

10
The RF Workbench / Re: AD9833_SPI
« on: December 08, 2019, 2232 UTC »
One reason to not use a microcontroller is that I don't like the arduino IDE.
If what I'm trying to do now does not work I may try using the USBASP as a controller. It has an ATmeg8 chip on it. Also I found this tonight:

https://blog.podkalicki.com/how-to-compile-and-burn-the-code-to-avr-chip-on-linuxmacosxwindows/

I like command line stuff!

~

I think you have to use a micro, whether you get a board that comes with one pre-programmed or not.
If you like command line, what I would recommend is writing some serial control code that translates between the serial and SPI. This way you can develop your own "command line" that works exactly how you want. If you buy something, it is unlikely to meet your exact needs. You can then use a serial to USB and a terminal such as Realterm.
It's not that hard to do. You can just read strings from the port and then do a bunch of IFs or a switch. First split the string by space. Send the first part through the switch statement, and then use the rest for your parameters.

I don't like Arduino much either. I use MikroC Pro for PIC. I use PIC chips for all my stuff, but they make software for Atmel as well.

11
The RF Workbench / Re: Question about stretchy 350W SiC deck
« on: December 02, 2019, 0833 UTC »
OK, I'll send a PM...

I see, so the match is a lot like this, but with only one core for the transformer:



Interesting they say to omit the L for 40m.

Wonder if it would work at all if you just omit both and just use a 4:1 transformer. Probably not as well, but I'm kinda curious. I will try on mine and see what happens.

I ordered a T200A-2 core for my design. I'll try the match as you suggested and if I still have trouble, then I will order yours.

12
The RF Workbench / Question about stretchy 350W SiC deck
« on: December 02, 2019, 0203 UTC »
Hey stretchy,

I am back at the shortwave transmitter again. I've had it working great below 4 MHz, but now I am back to trying to make it work higher again. I thought I had it at 87% efficiency, but I looked on a spectrum analyzer and it's terrible. When I run it next to the filter, then it's great, but only 76% efficiency @ 6.8 MHz. I am almost 100% sure it has to do with my broadband output match.

Anyway, I'm thinking about buying your SiC RF deck. The 350W one with 4 fets I believe. How much would that cost?

I know you use those T200-2s. What else do you have to match the output beside the transformer?
Yours is not wideband, right? you have to tune it to the band?

13
I don't understand the fixation on using higher frequencies. Just use more power and bandwidth instead. The cost will be lower also because then they won't have to install a base station every couple of feet (I'm exaggerating, but you see the point.) and can use existing infrastructure. Using 400-800 MHz seems the smartest to me because the antenna is about the size of the phone itself and a relatively efficient antenna can be made, but with these crazy high frequencies, it's not going to go very far at all. If they just use the best QAM with wide bandwidth and high compression, they should be able to make it work on the existing frequencies. The government probably regulates the bandwidth on those frequencies though, which could be the reason. Stupid government.

I don't know about toxicity, but I would think it is still below ionizing radiation.

5G could be a good opportunity for replacing the government with blockchain technologies. You need every device to have a copy of the blockchain for security purposes and with the speed of 5G, it could likely be possible. Blockchain is basically like virtual DNA - where each item contains the whole. The government will obviously hate this idea though, but it really needs to happen. All of the government agencies could be paid automatically and directly through the blockchain and eliminate the money getting into the hands of corrupt bureaucrats.

14
Veganism is a cult plain and simple.
My hypothesis is that due to lack of religion in modern society, we have these groups such as SJW and Vegans that treat arbitrary things as their religion. Most vegans don't base their thoughts on facts, but instead on blind belief.

15

Why would you use a linear amplifier for FM service?  LOTS of wasted power.

+-RH

Don't you have to use a linear for VHF band? Confused  :o

I could see what you mean about shortwave though. Using a linear on shortwave is a waste, but on FM...

Maybe I don't know enough about the other classes of amplifiers out there for FM band.

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