Hacker News Reader

Comment by DoingIsLearning | Hacker News Reader

The BBC World Service shortwave broadcast [0] is still one of the few (safe) ways people can get outside news while living in war-torn regions and totalitarian regimes across Africa, Middle east, and Asia.

People arguing about Audio quality are missing the point of AM: Robustness in adversity.

Receivers are easy to put together and repair, transmission travels long distances beyond enemies/oppressors and unlike online access nobody can intercept your traffic or estimate your location.

[0] https://www.bbc.co.uk/programmes/articles/2x9tqt6mc05vB2S37j...

View on HN

BBC Arabic was just discontinued last week. FTA: The move came as part of cost-cutting measures under which the news service is also ending its radio programming in 10 other languages, including Persian, Chinese and Hindi.

https://www.nytimes.com/2023/01/30/business/media/bbc-arabic...

Having discontinued most of the over the air broadcasts to Eastern Europe they turned them back on pretty quickly starting in February last year - I've no doubt that once Ukraine is finished the Foreign Office will be nagging to withdraw the funding again.

So stupid, it's a lot of soft power for peanuts. Probably the suits are saying "but what about the internet" but the people you want to reach are the people whose internet is likely to be turned off when you want to talk to them.

You might have missed that Broadcast onto Ukrain territory / Central and eastern Europe in general has been turned off again.

That's tragic and shortsighted... for whatever faults BBC coverage might have, those 39M listeners it was reaching will now no longer have these alternate perspectives easily available to them relative to the other media in their countries. Less information is always a loss. And even if we ignore any altruistic motivations, it's a loss of soft power for the British / Western operations.

> That's tragic and shortsighted

Tragic absolutely, shortsighted - no. You can't operate without money and news organizations can't survive in todays environment. The way we consume and gather around information simply isn't the same anymore.

it's the bbc, they are state funded.

They were funded by a separate tax that everyone had to pay which got discontinued recently.

The TV license is still in effect and not everyone has to pay it. [1]

How on earth have you obtained such obvious misinformation and why are you posting it so confidently?

[1] https://www.gov.uk/tv-licence

World service was funded separately from general taxation until a few years ago.

It's an absolute disgrace and I hope everyone who is represented by an MP is writing to them to protest. Its bad enough to Brexit but to willingly give up soft power to save a tiny sliver of budget is shocking.

Whoever figured "well its on the internet" appears to have forgotten that its purpose is to serve people under the sorts of governments that would aggressively block internet access to news sources unfriendly to the government.

On another note BBC Hausa service is facing mass resignation due to the newly opened TRT Hausa service (Turkey) promising the staff the BBC staff freedom to report positive News about Africa, unlike the BBC that only wants them to report negative and News about war and underdevelopment.

Receivers are easy to put together and repair

See https://en.wikipedia.org/wiki/Crystal_radio and https://en.wikipedia.org/wiki/Foxhole_radio

Building a receiver out of whatever scrap you have around is a highly recommended exercise, and even more so if you have any kids (do it with them) --- the astonishment at seeing a pile of parts come together and make sounds, seemingly without any power source, is definitely an unforgettable experience.

The electronic gadgets that surround us inevitably have their roots in tangible physics, so projects like this that demonstrate that fact are enlightening and wonderous.

Radio was among the first means of long-distance, widespread wireless communication owing to its simplicity, and that simplicity means it's very hardy against adversity and unlikely to meet its practical demise any time soon.

Not to be pedantic, receiving is actually traceable to a motivated enough agent with sufficiently expensive equipment, especially if your receiver is home made or poorly built, due to oscillator leak back, there are a few other effects that can be used such as shadow casting. This gives a light idea of what’s possible: https://ham.stackexchange.com/questions/2160/is-there-a-way-... I simply mention this because in some regimes and some situations, it’s best to understand what’s possible.

I'm sure you're right that a "motivated enough agent" might trace a receiver but the two replies in the ham.stackexchange.com answer seem pretty clear that it's very difficult to do in the real world.

I appreciate technology may have changed but in the cold war many East Germans listened to the BBC East German service, in particular a programme called "Letters Without Signatures" [0] which relied on East Germans writing letters to the BBC . The programme ran for many years and clearly had a significant audience, I think if the Stasi had been able to detect reception they would have done so.

[0] https://www.bbc.co.uk/blogs/bbchistoryresearch/entries/9a651...

Odds of being tracked down that way are near-nil given that your oscillator could for anything. Also you can build a crummy AM receiver without one: https://www.buildcircuit.com/how-to-make-a-batteryless-cryst...

I had a "bionic man" doll when I was a kid that had a crystal radio built into his back (although on reflection it might have been the 3 faced robot guy).

Seemed like magic at the time, got me into simple electronics.

> not to be pedantic

(proceeds to be extremely pedantic)

Same goes for Tor. If you're one of 3 using Tor in your entire city, it won't be difficult to target you. This kind of stuff only works well when its used en mass, making the government have too many targets to bother.

You don't need a local oscillator to receive AM.

However, a nonlinear junction detector will still find a receiver (among other things).

AFAIK only if you are using a het-design receiver, a DSP receiver should be immune to that tracing?

It would need to sample baseband. If you are using an LO to down-convert or up-convert that would be detectable.

Doesn't BBC WS broadcast over shortwave, not AM? I used to listen to it in many different countries (though no longer because ... Internet).

They used to have an AM transmitter that reached most? of Europe, but it was shut down in 2012: https://en.wikipedia.org/wiki/Orfordness_transmitting_statio...

Broadcast shortwave (and long wave) uses Amplitude Modulation, the term "AM" has been hijacked in some forms of English to mean "medium wave" but it's not what it means to radio engineers etc. I can't complain because I regularly refer to VHF broadcasts as FM ;-)

BTW in addition to shortwave BBC World Service broadcasts (or provides material for rebroadcast by local operators) in : Long Wave; VHF; DAB and Satellite.

Honestly FM receivers are not much more complicated than AM receivers and are much better. A full superheterodyne is not necessary if you really are in a survivalist scenario. A single transistor is the only non-linear component.

https://www.circuitbasics.com/what-are-fm-receivers/

Yeah but propagation.

FM is far more restricted by line of sight.

AM is not dead between cities in Texas, if you're into Country, Tejano, or church broadcasts.

The modulation, AM vs FM isn't necessarily the big determine factor on distance. AM can general travel farther on less power, but its more about the frequency choice. FM radio stations usually operate in the VHF/UHF band, which regardless of the modulation technique, it much more likely to be line of site. AM radio stations tend to operate on HF. HF frequencies have a higher change to do bounces. Its more about characteristics of the frequency being used in this case. Under the right conditions, the 6m band, even with FM, can experience "sporadic E" and you can talk quiet far on it.

FM does not transmit to thousands of kilometers...

Only because of the frequencies typically used, not because it's FM

No. The maths show that AM can be received at much lower signal-to-noise ratios.

And FM is intolerant of multipath reception which happens a on SW.

The FM receiver that you linked to is actually an AM receiver, but it is using "slope Detection" to recover the audio.

And FM is absolutely not "better" than AM. It does give a clearer signal on strong signals, but is demonstrably worse on weak signals.

Just curious why they hopping frequency

Shortwave propagates differently during the day and at night. Its propagation is mainly due to bounding off layers of the ionosphere. Different layers absorb and reflect different frequencies. During the day (relative to the broadcaster) frequencies above 12MHz propagate farther than lower frequencies. At night this effect is reversed.

"AM" in radio context generally means medium wave, not shortwave.

AM in radio context means amplitude modulation - it’s the modulation, has nothing to do with the band. In common everyday layperson context it means all of medium-wave terrestrial broadcast.

But even commercial pilots know their radios are AM for instance.

I meant specifically the phrase "AM radio" - a product advertised as such will usually not be capable of receiving shortwave, unless that is specifically mentioned. People who know what AM actually means tend to use words like "transceiver" anyway, not "radio".

Is this an US thing? Because over here in 80s radios had "long wave", "medium wave", "short wave" (1..6) and "ultra short wave", the later being called "FM" in export models. I do not recall bands being reffered to as "AM".

Does it include LW/MW only, or is shortwave also called "AM radio"?

A common radio will have an AM band 530 kHz to 1700 kHz and a FM band 88 to 108 MHz. You'd have to buy a special radio to get more options.

If you look up "AM/FM radio" on Amazon, you'll see plenty of examples. It does not include shortwave, unless specifically labelled "AM/FM/SW". Whether LW is included or not varies, probably because LW isn't used for broadcasting in US.

I don't think it's just a US or NA thing. In my experience, at least, every casual consumer radio I ever handled that had English labels on it, outside of vintage stuff, used this terminology. More advanced consumer radios like Tecsun will usually avoid "AM" and use LW/MW/SW as appropriate, but then still refer to VHF as FM.

> People who know what AM actually means tend to use words like "transceiver" anyway, not "radio"

I referred to pilots as a counter example.

We know what AM really means and we call it a “radio.”

People also say CB radio - I’ve never heard it referred as a transceiver by that group. Hams, both.

Reply on news.ycombinator.com