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Any Shortwave Radio Tips for a Noob Considering the Hobby?
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edy:
Thanks again for all the advice! I ended up biting the bullet and ordered the Tecsun PL-310ET from Amazon. It was roughly ~$43 US or $57 CAN with free shipping. I had about $50 CAN saved up in Amazon gift cards already (for filling out some Developer surveys over the past year) which covered almost all of it. And best of all, it will arrive in 1-2 weeks instead of 2-3 months (like stuff I order from eBay)!  :-DD

Meanwhile I have the following e-books to read through:

  Ham Radio For Dummies 2nd Ed (2013)
  The ARRL Ham Radio License Manual (3rd Ed) - Technician
  The Beginners Handbook of Amateur Radio (4th Ed)
  Basic Amateur Radio Course (EmComm)

So that should get me started and "scratch the itch" with minimal cost invested at this point, to see if I enjoy and want to get into the hobby more. Again, the issue is mostly time. I am already stretched thin with work/family and the wife/kids are not going to enjoy this unless I bring them along with the hobby. So I think this is an easy way to nudge along, do some family listening and exploring and learning.  :-+

Once I have had my fill of the Tecsun, I will probably explore a RTL-SDR dongle. I run Ubuntu Linux so will need to play around with some of the software and get drivers to make it work, plus figuring out how to set up some antennas. I don't have the ability to go crazy with antennas, so I think I will need to find a solution involving some wires that I can string up in the upstairs bedroom temporarily when I am using the radio, or a clip-on wire that I can make myself (I have plenty of 1/8" jacks, wires and metal clips, coax cable, etc). I was tempted to buy one of the Tecsun "retractable wires" that came suggested by Amazon for another $15 but reviews were mixed as to how much better it was over the standard flip-out telescopic antenna already attached to the unit. So before I shell out more money, I will try the existing antenna and if needed I will try to build something out of scrap from home and see if it helps.

Yes I also agree that both the Tecsun and RTL-SDR are cheap enough and fairly portable so I can move them around and play with it on trips, at work, camping, etc.... I looked at some of the cheapest SSB options and they are at least 2-3x the cost of this model. They start around $100-150 CAN and quickly go up in the $200+ range. I also realized that most Ham used equipment is still going to fetch a fairly high price, and anything that is in the lower end is not going to have the convenience of this Tecsun with digital tuning and memory presets. That is the reason I chose the PL-310ET over the R-909, which is less than half the price ($15-20). The tuning on the R-909 will make life harder. At least with a digital display I can save and log signals I find.

I also got the Tecsun manual which I downloaded from here:

https://www.tecsunradios.com.au/store/wp-content/uploads/2015/12/PL-310ET-MANUAL.pdf

It shows the following frequency range:

FM   87~108 MHz
   Russia   64~108MHz
   Japan    76~108 MHz
   EU, USA  87.5~108 MHz
MW     522~1620 kHz
   USA 520~1710 kHz
LW 153~513 kHz
SW 2300~21950 kHz

I am assuming that "FM" specifically looks for FM signals in that range (Frequency modulated mode). Then should I assume that the signals that are interpreted by my Tecsun in the other ranges (MW, LW, SW) are going to be considered all be "AM" type (amplitude modulation) of the carrier wave? I have seen that all kinds of signals can be transmitted at all kinds of frequencies, from digital signals to TV/picture, to AM/FM encoded and more. I guess the radio will hear a bunch of weird noise when I tune into those frequencies if it is not AM? Will plugging the output into my computer and recording the sound and using some decoder on it be likely to decypher anything? I guess the RTL-SDR software will have various modes that I can use (or it will detect) at each frequency to try and figure out what type of signal is being broadcast?

Anyways, I'm jumping ahead of myself. First step is finish reading those e-books while I get my early Christmas present and exhaust the potential of the Tecsun! I think after that I will pick up a RTL-SDR kit and will be kept busy a few more years playing with that on my Linux machine. With my limited time, I will be kept busy enough with this hobby for the foreseeable future with <$100 worth of equipment!   :-+

fourfathom:
I just downloaded the Tecsun manual, and I *hope* that Tecsun PL-310ET has a BFO!  I can't see how to activate it though.  The marketing blurb says "Special design of SSB demodulation functions, can receive amateur maritime communications and personal radio", and since HF (3-30 MHz) maritime communications use single sideband the radio will need some sort of BFO function.  This radio actually uses a SDR design, which can be very effective (or may be marginal).   One deficiency that I hadn't noticed is that on the HF bands the radio only tunes in 1KHz steps.  This is fine for AM, and for channelized SSB (such as maritime), but for ham and digital modes you may want 100Hz steps.  I see that the radio uses a 32KHz crystal for it's internal clock, and given the typical accuracy of these (perhaps +/- 20 ppm) I think that some kind of "clarifier" or fine-tune control would be useful.  Again, for regular shortwave listening this won't matter much.

Regarding frequencies and modulation, while you can find all types of modulation all across the radio frequency spectrum, the Tecsun (and other similar radios) are designed to demodulate FM when tuned to the standard FM radio broadcast bands (88-108 MHz in the USA) and perhaps the television broadcast bands (where FM is used for the audio channel, at least on the traditional non-digital frequencies).  Elsewhere, the radio will be using its AM detector.  One type of AM is SSB (Single Sideband), and the radio has a BFO (Beat Frequency Oscillator) you can enable which will let you receive these signals.  With the BFO you can also demodulate CW (Continuous Wave, used for Morse code) and FSK (Frequency Shift Keying, use for many digital modes).   Decoding these digital modes can be done by sending the audio from the radio to a computer soundcard input and running one of the many programs designed to decode one or more digital modes.  You *need* a BFO to demodulate CW, SSB, and FSK, and the cheaper receivers don't have a BFO.

This computer decoding is one reason I like the SDR dongles, since with these you don't need an audio cable and you can have direct computer control of the radio frequency and mode.  This ability can really simplify the setup and avoids many potential grounding and power supply noise-related issues.  Of course if you just want to listen to shortwave broadcast stations then these additional capabilities aren't a big deal.  But in my opinion, most of the interesting stuff in ham radio radio is going on in the digital communications domain (I've been a ham for about 45 years.)

Again, bang-for-buck when it comes to a wide-range SDR I really like the "SDR-Play RSP1A".
bob91343:
The frequency spectrum is broken into sections by terminology.  MW is Medium Wave, or the AM broadcast band.  Then comes SW, short wave, from 3 to 30 MHz.  This is also called HF, or High Frequency.  Then comes VHF, 30 - 300 MHz.  UHF is from 300 MHz to 3 GHz.  And so on.

In your case, your primary interest would be MW and SW/HF.  There is very little radio propagation above around 25 MHz these days.  In fact, the main range is perhaps from 5 to 15 MHz the way the ionosphere is acting.  Yes there is other stuff to hear but it's mostly noise.

As an old time ham operator I can say it's one of the most fun hobbies I have.  Last night I listened mostly to noise but contacted Hungary.  Night before, Japan and Philippines and South Africa.  It's exciting when a distant station responds to a call.  I have worked well over 300 countries, all states and all continents, including some very rare places like Eritrea and North Korea and Southern Sudan, etc.

Of course, this comes with considerable investment in time and effort and space.  Not money really, as much of my gear came from swap meets and trades.
edy:
You are correct, I do not believe there is a BFO in the Tecsun. However, I have found some people who built their own outboard BFO for SSB reception. Here is one of the websites here:

https://wf7ihomebrew.wordpress.com/2019/06/30/outboard-bfo-to-add-ssb-capability-to-am-radios/

And here is the schematic:



And built in a tin:



A fun little project if I want to start exploring this area as well! I will check out the SDR-Play RSP1A. It seemed a bit pricier than the RTL-SDR.COM V3 option (they have a full kit for <$30) but it's probably much better. So many options, so much fun to be had, so little time!   :scared:  Wow. More excited than ever!  :-+
fourfathom:

--- Quote from: edy on December 09, 2019, 05:47:59 pm ---I will check out the SDR-Play RSP1A. It seemed a bit pricier than the RTL-SDR.COM V3 option (they have a full kit for <$30) but it's probably much better. So many options, so much fun to be had, so little time!   :scared:  Wow. More excited than ever!  :-+

--- End quote ---

The RTL-SDR V3 has essentially no input filtering, and when used on the HF bands it is in a "direct sampling" mode which samples the RF input at 28.8 MHz.  Without an external filter this leads to pretty terrible "aliasing" artifacts, where input signals above 14.4 MHz get "folded" back down to the 0-14 MHz region. 

As an experiment I built a receiver / digital gateway for one of the ham digital modes ("JS8" on 10.130 MHz) using one of these SDRs and a Raspberry Pi.  With external filtering and a preamp it works reasonably well.  Here is a presentation I gave to my local ham club that has some details on the SDR and how I put it all together: http://wb6cxc.com/wp-content/uploads/2019/04/Presentation-1-0.pdf  This is a narrow-band system operating on a single frequency, and it would be more difficult to turn this into a useful general-coverage receiver.  The SDR-Play and Funcube SDRs do all this filtering and conversion stuff for you and they do a darn good job of it.  The cool thing about the RTL-SDR V3 dongle is that it works in the HF band at all, is very cheap, and has a reasonably stable oscillator.

You can certainly build an external BFO, but making one that is tunable and stable can be a challenge.  These days I would use digital synthesis for the VFO, and the parts would cost me under $10.  One problem with the external VFO concept is that it doesn't give you "opposite sideband rejection".  You can still tune in a SSB signal, but you will get more background noise and potential interference.

But don't let me discourage you from building stuff!  That can be a lot of fun and a great way to learn.  One of the simplest receivers you can build is a "direct conversion" design, consisting of a BFO, a mixer, and an audio amplifier.  With just a very small handful of parts you can put together a receiver for AM and SSB.  I love designing and discussing this stuff, so feel free to ask any questions you like.
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