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Is this a good thread if I'm an absolute beginner? There used to be a megathread in some other forum but I can't find it.
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Jan 9, 2021 19:52
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net work error posted:Is this a good thread if I'm an absolute beginner? There used to be a megathread in some other forum but I can't find it. yes
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Jan 9, 2021 19:56
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yep no question is too basic. this a safe area to ask whatever
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Jan 9, 2021 20:00
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lmao its impossible to know less about this than me. i am the epitome of nerd with a general ticket that knows precisely jack and poo poo
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Jan 9, 2021 20:01
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I know just enough about ham to score a 32/35 on the tech test I took last night lol. I'm just waiting on a callsign so that I can share my ignorance with anyone in repeater range.
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Jan 9, 2021 21:19
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Jonny 290 posted:yep no question is too basic. this a safe area to ask whatever So if I'm starting from absolute zero what are the goon recommended resources? Alternatively if you have a link to the old thread I can checkout the links from there as well.
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Jan 9, 2021 21:26
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listening is always the first key. i still recommend the rtl sdr sticks for somebody with literally zero gear. https://www.amazon.com/gp/product/B011HVUEME/ref=ox_sc_act_title_1?smid=A37V0QGFC9C912&psc=1 hamexam.org is a good practice test site. other'n that, it's most helpful to just ask - what is your environment, and what are you interested in? Some things like operating on HF ("shortwave") from a 9th floor apartment building can be difficult. An increasing number of (mostly younger) hams have taken to portable operation and will go throw a wire up in a tree in the park for the afternoon. further clarification that when i talk about 'young hams' im talking about any under 55.
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Jan 10, 2021 02:43
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I'm probably not too hampered in terms of environment. As far as goals, for now I would probably just listen and maybe learn enough to be of some help in a disaster scenario like after a hurricane or something. Your post about the baofeng's in another thread made me realize I don't know a thing about radio and it seems like a handy thing to be familiar with.
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Jan 10, 2021 03:18
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I live in a 14 story apartment building on the 8th floor and I don't have roof access. I do have a balcony, it is about 1.5m by 4m. I was wondering what kind of antenna setups would be useful. Maybe something that I can put horizontally along the length of my balcony. I have various RTL sticks, a LimeSDR mini, an HF upconverter, some 2m and 70cm portable gear (and a couple of baofengs :v)
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Jan 10, 2021 09:10
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I upgraded my license to general class during covid and ended up enjoying the arrl license material. I can deff appreciate that it teaches you stuff thats current like ft8 operating procedures and then core knowledge stuff is helpful for troubleshooting which youll probably do almost immediately while setting up a station also I live in the city proper and have managed to string up a stealthy 40meter monoband antenna and have had good luck with digital modes. i have an s5-s9 noise floor so if it weren’t for digi modes my enjoyment of the hobby would much rougher
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Jan 11, 2021 23:31
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Jan 12, 2021 09:40
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my father in law (ex now I suppose) must be a ham man. he worked for tait for like a thousand years. they wanted to make him redundant at some stage but his redundancy was going to cost too much so they just kept him on lol
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Jan 12, 2021 11:47
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Jan 12, 2021 11:54
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this might be a stupid question but how much in a 'day to day' sense is all the electronics related stuff? learning about ohms and poo poo is great and interesting and good for me but i'm having a ton of trouble wrapping my head around that part of the exam study guide i got (canada) and it's stressing me out kinda. i'm moving in a couple weeks and i'm excited to set up my rtl-sdr again in an environment where i have more control, being downtown in a 10th floor condo was cool but stressful kinda
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Jan 13, 2021 04:30
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Jonny 290 posted:Ideally if you want to use one of the rtl sdr "v3" sticks (which have built in shortwave functionality) on lower frequencies, you'd put a box that is a combo antenna matcher and attenuator in front of it, because it has no gain controls down on AM/shortwave. everything is full throttle. and as a result, since AM broadcast signals are like 10000x stronger than weak shortwave ones, the former just overloads and you hear local nazi sports talk radio every 10khz. They do very well when you have a preselector or attenuator ahead of them, between the SDR and the antenna. i've been thinking about this a little bit. do you get the repeating signals because the input is so big that it's clipped (and if it's clipped you obviously just lose any small signal on top of it)? if that's the case i get why you'd get higher frequencies than the fundamental since you've got some kind of square wave but how do you end up with lower frequencies? edit: ok nevermind, i was confused. i was trying to understand the image i posted earlier but i think that just has to do with stereo FM radio broadcasting and no weird extra harmonic poo poo. Eeyo fucked around with this message at 03:26 on Jan 14, 2021 |
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Jan 14, 2021 03:12
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When you get into SDR land, the old "sum/difference" and "harmonics" rules no longer apply. Its basically 'how does an overly strong AM broadcast signal gently caress up the ADC on a cheap SDR' Calvinball, really. But running a highpass filter that nukes everything below 1.7, 1.8 MHz cleans up any SDR stick (depending on where you are, you really don't care about anything below the 540KHz bottom of the AM band. You can tune in to some beeps for non-directional aircraft beacons, and if you're in Europe you can listen to the longwave broadcast band, but those are the sole exceptions)
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Jan 14, 2021 03:14
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i finally ordered myself a nanovna. i'm excited because it'll let me try out weird antennas to see what's possible without actually owning an hf transceiver
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Jan 14, 2021 04:33
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Eeyo posted:edit: ok nevermind, i was confused. i was trying to understand the image i posted earlier but i think that just has to do with stereo FM radio broadcasting and no weird extra harmonic poo poo. Are you talking about the stripes above and below the main FM channel? That's digital HD radio carefully tucked into the guard bands of the original FM radio standard. The harmonics will show up at multiples of the fundamental frequency, and because it's multiplied its bandwidth is twice as wide each time it shows up. So your FM station at 100.3MHz if you were getting some clipping on the front-end would show up again at 200.6MHz but 20kHz wide instead of 10.
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Jan 14, 2021 05:08
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Achmed Jones posted:i finally ordered myself a nanovna. i'm excited because it'll let me try out weird antennas to see what's possible without actually owning an hf transceiver i have spent a surprising amount of time just looking at the impedance vs frequency of lengths of bent wire-- would recommend.
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Jan 14, 2021 05:13
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Stack Machine posted:Are you talking about the stripes above and below the main FM channel? That's digital HD radio carefully tucked into the guard bands of the original FM radio standard. no i mean when there was no audio transmitted i could see several distinct frequency components that were evenly spaced by ~20kHz. i gather that's the 19kHz stereo pilot tone, but i'm picking up copies at 2*19, 3*19, etc. i was expecting there to just be the carrier frequency when the transmission was silent and was puzzled why i saw so many of them.
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Jan 14, 2021 05:45
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oh gotchya.  .Stack Machine fucked around with this message at 06:32 on Jan 14, 2021 |
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Jan 14, 2021 06:16
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so I cranked up the LNA gain until the IF stage started clipping to get a screenshot of the second harmonic of an FM station. It wraps around to a lower frequency in this case because of nyquist, but if it was clipping on the input side it would be up at 210MHz instead. Fortunately I don't have any stations close enough to clip at the LNA input: 2 things this illustrates: the second harmonic looks like a weaker double-width copy and (2) RTL-SDR dongles will happily let you turn up the LNA gain until signals that aren't really there start to show up.
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Jan 14, 2021 08:08
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all of this is very interesting and intriguing but at the end of the day I have to ask myself.: do I really want to talk to other dudes on the radio and I just don’t know. which is a shame because the idea of setting up some kind of neighbourhood beacon of radio waves is somewhat appealing
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Jan 14, 2021 08:12
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an RTL-SDR kit that's $40 USD in the states is $120 CAD in the great white north, *gently caress*
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Jan 14, 2021 11:32
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lol i just read about the zimbabwean dollar and in 2009 thatd be worth about 1 trillion zimbabwe dollars
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Jan 14, 2021 11:41
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Kazinsal posted:an RTL-SDR kit that's $40 USD in the states is $120 CAD in the great white north, *gently caress*  apparently the 3080 graphics cards that are about $800 ($1200 scalped) in the USA are going for as much as $3000 CAD up there. lmao
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Jan 14, 2021 20:14
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my 1080 is good enough for now and im gonna wait for the 3080ti whcih will probably be like q2/q3 this year. prices are insane all over.
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Jan 15, 2021 00:15
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net work error posted:I'm probably not too hampered in terms of environment. same. just picked up one of those rtl sdr kits. there's no time like pandemic time. happy radio journeying, fellow beginner.
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Jan 15, 2021 00:57
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Jonny 290 posted:listening is always the first key. i still recommend the rtl sdr sticks for somebody with literally zero gear. I just got this SDR stick! What's a good app to install and just gently caress around with to listen to whatever I can?
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Jan 23, 2021 21:01
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oh hell yeah i use SDRSharp on windows and gqrx on mac. And i guess technically OpenWebRX for linux - though that's a web based server. (it's very cool) Follow the driver instructions carefully. there's a little hackin' to be done before it'll show up.
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Jan 23, 2021 21:03
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I've spent like two days getting my LimeSDR Mini to play nice on my raspberry pi 4 with ubuntu 20.04. Now I have SoapySDR working, srsLTE working, gnuradio 3.8, osmocom, gr-gsm, etc. Next step is writing my own SIM cards so I can do 2G-3G-4G MitM on IoT devices that have their own GSM connection.
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Jan 23, 2021 21:17
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The LimeSDR mini seemed like a good buy at the time and it's a powerfui beast. But it is VERY finicky.
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Jan 23, 2021 21:17
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Jonny 290 posted:oh hell yeah I set up SDRSharp, it wasn't too bad. Listening to local CB radio now and no idea what's going on but I like it.
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Jan 23, 2021 22:01
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net work error posted:Listening to local CB radio now and no idea what's going on but I like it. basically me for the past 29 years Suspecting you aren't in the US? Is this UHF CB down in aus or something?
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Jan 23, 2021 22:09
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Jonny 290 posted:basically me for the past 29 years No I'm in the US. I just looked up one of the tutorials on the SDR site and it gave me the frequency range for CB and it also shows it as that in SDRSharp. 26.965-27.115 MHz?
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Jan 23, 2021 23:02
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no thats really cool. cb is often very quiet. glad you could pick some up. 27.185 is ch19 and the most popular freq
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Jan 24, 2021 03:57
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spankmeister posted:I live in a 14 story apartment building on the 8th floor and I don't have roof access. I do have a balcony, it is about 1.5m by 4m. Would still appreciate guidance on this.
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Jan 24, 2021 12:00
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what is the rudest frequency, like the one with the real freaks on it
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Jan 24, 2021 17:34
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spankmeister posted:Would still appreciate guidance on this. for HF i'm still enjoying the MLA-30+ loop. you'll need a stick or something to put it on, but it will likely do well from MW broadcast all the way up through 20, 25 MHz. bout fifty bucks USD, worth it imo.
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Jan 24, 2021 19:04
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croup coughfield posted:what is the rudest frequency, like the one with the real freaks on it 14.313 7.200 3.840 .435 repeater in southern California https://m.broadcastify.com/listen/feed/14747/web
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Jan 25, 2021 02:52
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