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Messages - audiokaos

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Got him here 5/9+10, great signal. Interesting playlist so far, a few I don't know in there. Thanks for the show!

General Radio Discussion / Re: Using HF rig as AM radio receiver
« on: November 11, 2014, 1540 UTC »
The best Am receiver I ever owned for AM was a Hallicrafters SX-28 but those are a bit hard to find these days.

Very true. Had a hallicrafters sw receiver as a kid & more recently a SX101. Tubes just love AM. Just finished restoring a Heathkit DX40 TX as well. Hope to get that on the air soon outside of just a dummy load.. Need crystals or gotta build a vfo first though...

General Radio Discussion / Re: Using HF rig as AM radio receiver
« on: November 10, 2014, 1821 UTC »
It also depends on what you're after from it. Looking to pull in distant signals or good audio? I have an Icom PCR100 that was fairly deaf RF wise, but you could really open up the audio bandwidth & it sounds great. But if there are high power local adjacent stations, you'll want tight bandwidth. In the States I hear IBOC is also a huge challenge for MW dx'ers, so not sure what the best route for that issue is. I'd guess you'd be stuck with squeeky sound, but could be wrong.

Software / Re: What Radio related software would YOU like to see?
« on: October 27, 2014, 1903 UTC »
fldigi ported to android... Heard it's not possible due to the graphics library that it uses though...:(

Winlink 2k would be neat too.

The RF Workbench / Re: Symptoms of an oscillating amplifier?
« on: October 24, 2014, 1843 UTC »
makeRF: I'm using the LM386 chip as an amp.

kaliic: The audio sounded fine, just quiet. The LM386 chip would get warm when transmitting.  It would get really hot running a speaker without resistors. It wouldn't get warm when running a speaker with resistors. 

Its not assembled anymore.  It was bugging me why the sound didn't carry very far.  I thought maybe because it was oscillating? I'll reply here if I tweak with it.


FYI you do realize that on a frequency such as 6925, the signal doesn't go that far locally right? It skips. Could have been clear as day 150 miles away.

Huh? / Re: Chuck Norris the DXer
« on: October 08, 2014, 1411 UTC »
Chuck Norris can wipe out all communication when he gets mad, by simply pounding his fist & causing a solar flare.

Equipment / Re: Good Antenna for Raspberry Pi
« on: October 01, 2014, 2201 UTC »
It's dead easy to build one. Just check out the ARRL's website - Loads of plans for antennas for pretty much any situation. Dipoles are very easy to construct - Just a T shape with the top bits cut to a specific length. Can be quite large though depending on the frequency. eg, for 6.925Mhz it is 33ft. 9 - 1/2in. or 10.299 M for one side...

General Radio Discussion / Re: RNI - Radio New York International
« on: October 01, 2014, 1805 UTC »
Very cool, thanks!

On top of what has been said about the TV sound aspect & it being out of band, it would be dead clear that it is a pirate signal. I personally wouldn't use it apart from tossing a signal from my living room to the bedroom..

Equipment / Re: Good Antenna for Raspberry Pi
« on: October 01, 2014, 1615 UTC »
Got it. So essentially, after I get the LPF, I'll just need an antenna tuned for the shortwave band I choose. Any broadcasters recommend a frequency or band, or is 6925 kHz good? Other than that, Woo hoo! I can combine my two favorite hobbies!

Pretty much - However afaik Raspberry Pi only uses the FM mode so apart from digital & actual FM I'm not sure what you might use it for. AM/SSB I believe is not possible with it - at least yet..<g> Check this out for some info on setting up LPF's and antennas-


Equipment / Re: Good Antenna for Raspberry Pi
« on: September 29, 2014, 1402 UTC »
After a LPF, the proper antenna for the band that you'd be using it for... The Raspberry Pi's GPIO is *very* noisy & harmonic. A LPF is very much needed.

Huh? / Re: Drone, ham radio destroyed amid headbutting assault
« on: September 17, 2014, 2024 UTC »
Hmmmmm, I wonder how big a drone would have to be to hold an antenna aloft....

Equipment / Re: Noise canceling systems
« on: August 27, 2014, 1353 UTC »
Good Day All :)!

I could get: Daiwa All Mode Active Filter AK606K , Datong FL1 and a Datong FL3, all in good condition!
All three in one 'packet' for 160 european coins ;D

My Question,anybody get some experience with this stuff?

Good DX!

First off, I'll say that I've never touched those, but I do work for a DSP company. Won't say the name as I don't want to come off as trying to sell - Amateur radio isn't our market & I don't want to come off like that.

Having said that, DSP processing is much tighter than anything analog in terms of EQ's. I can create notch filters at 48db per active using IIR filters or even more with FIR. Tighter than a nun's.. um, well, you know. At *any* frequency that I want. Analog can be good in certain bands, but aren't really configurable & have good bandpass cutoffs. Our processors are made for live sound/studio applications, but I've been using mine on my HF rig as well for just that. On top of it, I also do all my mic processing (ALC, Compression & EQ (I have a crappy mic)) in the same box. I'm sure that something like this has been developed for Amateur radio as well. Just something to consider.

Equipment / Re: Audio Processing
« on: August 25, 2014, 2115 UTC »
Well, just listening to folks like Wolverine Radio & I'm just amazed that they get the audio (music) sounding as good as they do out of SSB. I do audio work myself & just wondered what processing they used for SSB. I understand the AM/FM requirements very well, just that SSB seems that it would require much more work to get it sounding good.

Equipment / Audio Processing
« on: August 20, 2014, 1528 UTC »
So, what sort of audio processing best for SSB broadcasting? I'm guessing 6Khz bandwidth (Or 10?) ALC & Compression?

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