Why do VHF-UHF radios tend to be cheaper than HF ones? There are expensive VHF radios and relatively cheap HF ones, but finding a cheap VHF radio is much easier than finding a cheap HF radio. Why? Aren't HF radios simpler?
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4 Answers
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I think the premise of the question is actually incorrect.
The things that make a radio expensive are receive sensitivity, output power, frequency agility, and modulation/demodulation circuit complexity. VHF and higher frequency generation use to be a big cost in the radio, but there are now integrated circuits that can do this cheaply, and the cost of an off the shelf VHF vfo is now lower than a hand built HF vfo.
HF radios can be found or built for under \$150 easily. The catch is that they are simple, single band, low power, and have low sensitivity, just like the cheap VHF radios of the same price range. The super cheap VHF ham radios (under $50) cut a lot of corners and have dramatically lower sensitivity as well as corresponding spectrum impurities and splattering.
Additionally, expensive VHF radios exist that are multi-band, multi-mode, higher power, and have higher sensitivity designed for use in weak signal receiption.
And just to add a bit of economics to this, cheap HF radios are not in high demand, and so typically end up as kits. Cheap VHF radios are mass produced with a high level of industrial design and surface mount components, which dramatically decreases per unit production cost.
Also, to some extent, frequency agility and mod/demod can now be done cheaply in SDR, so this is now less of an issue than it use to be. Sensitivity can also be increased with SDR, but this is not yet cheap. (It's cheaper than doing it with analog components, but still more expensive than leaving it out.)
So, to summarize, expensive HF and VHF radios with feature parity will have a similar price. Cheap VHF radios might beat cheap HF radios purely due to mass production economy of scale. The final irony in this is that some modern cheap HF designs upconvert the signal to take advantage of cheap mass produced VHF components.
As an extreme example of this, you can get a complete broadcast AM/FM receiver in a single chip for under $2. Catch is, it is receive only, and it doesn't need any sensitivity because it is receiving a 20KW+ broadcast station 50 miles away instead of a 100W HF ham station 1000 miles away. (And broadcast AM is between ham HF bands and ham LF bands anyway, so HF/VHF not a factor in this.)
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1$\begingroup$ I'd argue price if a function of supply and demand, and the production (and design, and distribution) cost of a device just sets a lower bound on the price someone will offer a device at, but for the HF radios that OP wonders about, we're quite a bit away from that lower bound. $\endgroup$ Commented Nov 3, 2022 at 18:31
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$\begingroup$ Totally agree with you, except that the same holds true for high end VHF/UHF radios as it does for HF radios. $\endgroup$ Commented Nov 4, 2022 at 2:48
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$\begingroup$ Actually, high end UHF/VHF radios frequently are HF radios too, so it's hard to separate those. $\endgroup$ Commented Nov 4, 2022 at 3:00
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$\begingroup$ Which is why the high end radios also are expensive $\endgroup$ Commented Nov 4, 2022 at 7:29
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Why do VHF-UHF radios tend to be cheaper than HF ones?
That's an economic question, not a radio technology one. How many radios of either type are sold per year? For which of the two types will hence cheap mass-produced devices exist?
Who is more likely to spend more than a device is worth: Someone who needs a handheld radio, or someone with space for a HF antenna system?
Aren't HF radios simpler?
No. (Why should they?)
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$\begingroup$ Re. why should HF radios be simpler — "simpler" isn't the word I would use but I have sort of wondered similar. Often in DIY ham circuit writeups I'll see things like "audio construction is good enough for such-and-such", and HF strikes me as somewhat the same way, not nearly so "picky". But perhaps with HF the circuit impedances/parasitics/etc. that aren't nearly so critical are easy to get right up through VHF/UHF anyway in commercial circuit design and manufacturing, whereas the components (esp. inductors?) have to be bigger and harder to produce? $\endgroup$ Commented Oct 31, 2022 at 18:52
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$\begingroup$ @natevw-AF7TB ah! So, hm, multiple aspects in here that one might want to consider in separate questions: DIY ham circuits are pretty far from what you'd go with when you design an industrially produced radio – for many reasons! Then: The things that are "hard" in DIY circuits are the things that take many components or very well-matched components, or such. In the age of electronics integration (so, 1960 to now), that's not a problematic circuit. The things that are "hard" for integrated circuits are often quite different (filters for low, for example, are harder than for higher frequencies) $\endgroup$ Commented Oct 31, 2022 at 18:59
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$\begingroup$ There's a solid chance that someone building a lower-cost, but still nicely selective HF receiver in 2022 would got and mix basically the whole HF band up to a higher frequency, to benefit from available filters. After you have a band-limited IF signal, it doesn't matter which band your signal originated from. The question is whether the application "HF reception" would then not call for a higher dynamic range, which would require a nice LNA before the mixer, which is problematic at frequencies that are so low. If you can live, noise-wise, with amplification after the mixer, things become $\endgroup$ Commented Oct 31, 2022 at 19:06
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$\begingroup$ cheaper. Either way, you'd need to look at what the requirements in terms of dynamic range and noise figure are, and that decides how much effort you need to put into your circuitry. For sub-microwave frequencies, and for the diminutive bandwidths that you find in analog modes on HF, VHF and UHF, the frequency and bandwidth aren't cost factors. The cheapest ADCs you could buy for the IF would do sufficient sample rate. The question is whether your amplifier chain and the ADC bitdepth suffice (hint: bitdepth usually suffices). $\endgroup$ Commented Oct 31, 2022 at 19:08
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Most VHF radios are relatively low power. They need to reach the closest repeater or just a few miles to another radio in simplex. They are not used or long distance. They typically are only VHF or VHF/UHF. Most are restricted to FM modulation. Also many VHF HAM radios are variations of commercial VHF radio which are produced in relatively large quantities.
HF radio tend to be higher power, cover many different bands, have several different types of modulation (FM, SSB, AM, CW, and so on). They are also produced in far smaller quantities as they are only used by HAMs.
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HF is rarely if ever used for commercial 2-way communications. Cheap radios such as the Baofeng/Wouxun UV-5r evolved from cheap commercial radios for the public safety and commercial bands. 10-meter radios also run relatively cheap for a similar reason: The CB bands just a few hundred kHz away. FM is also cheap to generate and cheap to receive, and Walkie-Talkies and base station radios in other services such as FRS/GMRS and Marine VHF also use it. Plus: The IC-9700 and the 905 and other high-end VHF+ rigs are as expensive or more than their corresponding HF rigs (IE 7300 and 705)
