178 lines
15 KiB
Plaintext
178 lines
15 KiB
Plaintext
Episode: 4633
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Title: Ham Radio Licence
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Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr4633/hpr4633.mp3
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Transcribed: 2026-07-31 16:15:35 (official HPR transcript)
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---
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This is Hacker Public Radio Episode 4633, for 2026-05-06
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Today's show is entitled, "Ham Radio Licence"
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The host is Lee and the duration is 00:14:23
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The flag is Clean, and the license is CC-BY-SA
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The summary is "Lee talks about the curriculum of the Radio Society of Great Britain Foundation Licence"
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You are listening to a show from the Reserve Queue.
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This show was submitted in June 2025 to cover occasions like this
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where there are gaps in the schedule.
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Hi I'm Lee, today I'm going to go on a brief tour of the Amterrajo Society of Great Britain
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Foundation License curriculum, with particular attention to the technical aspects.
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Why would you want to get this license? Well basically it's the bare minimum of what's required
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to legally operate what's referred to as Amterrajo or Hammequipment, particularly if you want to
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transmit using this equipment in the United Kingdom. If you're not in the UK they like to
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be other foundation level licenses that you can take. The equipment itself may not be
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costly, it could just consist of handheld battery-powered walkie-talkie-style radio such as
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bow-fane that can be quite fun the 50 pounds aware of the equivalent is in your currency of choice.
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One of the first things that is taught is the basics of radio. This includes various symbols
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in units of a relate to electrical circuits such as amps for current and volts for potential
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difference. It talks about how both large and small quantities can be written down using
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different sizes of these units such as millimeters for distance rather than meters.
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We learn about batteries and how you can draw diagrams that represent an electrical circuit
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schematically and the fact that some substances conduct electricity while others don't so much.
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We also learn that there are more electrical quantities such as power which is the right
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which engines been transferred or resistance which is how much a particular conduct
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tends to limit the current flowing for it. One of the basics is a general formula which connects
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the three quantities of voltage current and resistance, either for a whole circuit on one part of it.
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It is noted that parts of the circuit may be aggregated either in series or in parallel with each
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other, depending on the topological layout of the circuit. The manual introduces electrical
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components such as light and knitting diodes or LEDs for example. We learn that electricity
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might flow for a circuit as you might expect in one steady direction called direct current,
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also that there is an alternative where electricity might be flipping direction very quickly
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and as alternating current. So the charge carrying particles called electrons don't get very far
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from where they started in that case and yet power is still effectively transferred in such a circuit.
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We learn that electrical signals can oscillate at a certain rate, that's their frequency
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and that different frequencies often combine which other in complex signals.
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The fundamentals of the electromagnetic waves we call radio waves are introduced
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and a description of the different frequency ranges of those waves is given since we distinguish
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between different types of radio waves according to their frequency. If you've ever used an old
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fashioned radio over dial, you'll know the radio always has to be tuned to a particular frequency
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to pick up a certain broadcast. The technical basics chapter covers the physical and mathematical
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properties that come into all waves, whether they be sound waves, water waves or electromagnetic
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waves. These properties are wavelength, speed and frequency and we learn a simple formula that
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relates these three quantities and at the same time a presented with some real-world examples
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so for example, the radio wave traveling at the speed of 300 million meters per second
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oscillates 300 million times a second and feeds oscillation travels one meter.
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The curriculum then goes on to describe a type of signal known as digital signal,
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when the information content of the signal has been decomposed into a large aggregation of bits,
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ishif which is only two possible states that may be described in several ways including
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as voltage levels so high or low or in logical terms, true or false or even mathematically
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one or zero. There are many situations especially nowadays we're sending information in the form
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of a digital signal is preferred in order to be more efficient or to help reduce interference
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and distortion. We're then told how real signals for which the proper term is analog can be
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converted to the more artificial digital signals which is necessary if they are to be transmitted
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digitally. There's a chat to in the amt to rage M and you're about receivers. We find out a
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rage or a receiver can often be compartmentalized in terms of its parts into an antenna, a tuner,
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strike amplifier, a demodulator, an audio amplifier and an output loud speaker. The curriculum
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covers knowing what each of these components does but also states that nowadays several steps in
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the process may be carried out digitally so that these components still exist but they're implemented
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logically with a microprocessor rather than being separate physical components you could see in touch.
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There's another chat to in the amt to rage or foundation manual about transmitters.
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Your basic transmitter will have it in this order a mic, an amplifier, a modulator, a rage or
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frequency pan, a fire and an aerial. We learn about carrier oscillators, these create a sinusoidal
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signal of a particular frequency and the measured signal is in some way piggybacked onto the main signal.
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So even if the rage or transmission in practice occupies a wide frequency range is this
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central carrier frequency that you normally talk about when saying what transmission frequency is.
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The modulation and demodulation is all about respectively combining or extracting a message signal
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with a carrier frequency to convert between the message signal you want to send or receive
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and the actual rage or signal going over the airwaves. I talked about this in particular in
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HPR4291. Various types of modulation discussed with names like FM, AM and CW.
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The first two are well known, with respectively the frequency or amplitude being the
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property of the carrier that's changed in step with the message. The latter is a little less
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known but stands for carrier wave modulation and just means turning the carrier tone on and off
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in some comprehensible sequence. The main example of this being Morse code.
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Side-banted discussed which are phenomena where the frequency spectrum of the rage signal
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shows a symmetrical pattern of frequencies in use above and below the carrier frequency,
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which is a direct result modulation. A final quantum modulation, again less familiar than
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FM and AM, at least if you grew up when those were how you listened to music, is data modulation.
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And this is where the signal is converted to digital ones and zeros and these decide what
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tones are played in console of each other while the data is being transmitted. If you are using
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the internet in the late 90s or early 2000s and had a modem you're probably not what that sounds like.
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We finally learn about the power amplifier which is the component that boosts the low-level
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electrical signal in your rage or handset up to something assessing lots of energy that can
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rage out from the antenna and travel long distances at the speed of light in the form of rage
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air waves. The syllabus covers learning about feed as an antennas. The feed is the
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wire that carries the signal from the sending equipment to the antenna and is often the coaxial
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cable meaning it has a central conductive core to carry the signal surrounded by an insulator
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and this itself is then shielded all around by conductive ramp. The idea is to stop the signal
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dissipating on rage editing away before it reaches the aerial. The other type of feeder which
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I'm not that familiar with is a twin feeder where two wires are used with a space between them
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and a signal of exact opposite polarity travels down each wire. We learn that feed has
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a property a bit like a resistance I mentioned earlier but this is called impedance. The thing
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that's important about impedances that signals will go through a system best when the impedance
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each stage is matched to have the same value as at all other stages. But most of what I've
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talked about so far is pretty theoretical but finally in the manual breaks is something very
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practical which is the types of plug for feeder cables. These have names like n-type, b-n-c,
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p-l-2-5-9 and s-m-a and you need to be able to recognize and distinguish between them. We also
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learn that for very high frequency rage o-waves, your typical feed decay was not so good but something
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called a wave guide which is like a square metal tube will do the same jobby.
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The manual then discusses the main categories of rage o-n-teller. That's the sticky
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up bit that emits or captures rage o-waves. I won't describe in detail but the main types of
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dypo-n-tenas, one quarter wave-gram planes, the yag-y-n-tena, the 5-8-wave-gram plane and the end-fed
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long wire antenna. We learn about the differing radiation pattern that emits from the different shapes
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of antenna which for example decides how much of the signal goes in each direction.
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For some purposes you want the signal to rage out in every direction, for other purposes you
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might want it to primarily leave or be picked up from a particular direction.
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The manual discusses the metrics used to describe the pair-up of particular antenna when being used.
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This is something known as the effective rage power and is related to what is known as the
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antenna's gain which is basically how good it is at putting out its signal and that depends
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on factors such as its size and shape. We also learn about polarisation which is to do with
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whether the rage o-n-teller goes out horizontally or vertically. So we're taught when debugging
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rage o-s at up a good thing to have is a special type of meter that detects how much of the signal
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is going into the air and how much of it is reflecting back into the equipment. For example if
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there is an impedance mismatch or the error is the wrong length. The meter is called does standing
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wave ratio meter or SWR meter. There's even a device that can sometimes sort out problems called
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an antenna matching unit or antenna tuning unit that's AMU or ATU. Another useful bit of kit is a
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bail-in. This can convert where you might have a coaxial type of feeder and really wanted to twin feeder
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which some type of variables such as a dipoware will require because the feed is then balanced.
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The manual talks about a dummy load. This is something that can be plugged in
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that will take in the signal perfectly as far as the transmitter is concerned with actually
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rage oating it as an aerial wood. This is useful for testing equipment. Another part of the
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syllabus is about rage o-wave propagation. That is how it travels through the air, how far it can
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go, what my alter its course dissipate it or affect it in other ways. We learn that there are
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three main effects. These are reflection, refraction and diffraction. Reflection is where the
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signal bounces back off something. Refraction is where it is bent towards a new direction and
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diffraction is where it scatters for example at the edge of something. The most interesting
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effect is the refraction of some wavelengths of waves as they enter the ionosphere layer of the atmosphere.
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This can bend the waves back towards the ground and it's this effect that means that some waves
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can travel between points on the earth, even when the earth's curvature would otherwise prevent
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this due to their being no direct line of sight through the air. The fact that the downward coming
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waves from the ionosphere can then even bounce back up from the ground or ocean and so do a
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back and forth between the ground and ionosphere for thousands of miles means that rage o-signals
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from a suitable transmitter can even be received on entirely different continents.
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And this is without the help of artificial satellites or undersea cables.
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So that's it, that's the main technical content of the foundation license.
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However, a lot of the syllabus which I won't go into in detail here is not just about
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technical aspects but also about being safe, responsible, alerting what the regulations across
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the world are that generally allow rage of transmitters and receivers to coexist with each other
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without people interfering with disrupting each other's important communications
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as they go over the airwaves. There's a chapter about practices and procedures for using
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ampturator equipment, things like announcing your allocated cool signs are that people know
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who it is they're hearing or communicating with. There's a chapter about safety from
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electrical safety working with high voltages to physical safety climbing ladders to SAR perials.
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There's a chapter about electromagnetic compatibility that's mainly about not causing
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interference to other people's equipment, particularly their TVs, rageos, phones or other
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wireless systems. Part of the syllabus is becoming familiar with the various bands that exist
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and how these can and can't be used. Since only select frequencies have been made available
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parameter transmissions, this is known as the in quotes schedule.
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Finally, the manual talks about the foundation exam. This may have changed slightly by the time
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you're listening to this, but when I took the exam in 2025, it consisted of 26 questions
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and I took it online with an refrigerator remotely watching a listening to me via camera and mic
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just to check the answers were my own work. In terms of what needs to be memorized a lot of
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the more technical data is made available in a data sheet that can be printed out and referred to in
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the exam. And there is a little maths, but most of it at this stage is trivial enough to be done with
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mental arithmetic, that simple calculator would be allowed to be used if desired.
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So for me taking the exam was a pleasant experience and while I struggled with some of the
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questions I finished well within half the lofted time and though I did not get full marks as
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called well enough to pass. I've only just started experimenting with the equipment so far
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with software defined radio reception and understanding the many settings of my handsets.
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At the time I took the exam I was in a ground floor flat so I was not having much luck reception
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wise, but now I'm living near the top of the adjacent building to where I was before,
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so it might be our fair better going forward. I know hand radio is a popular topic on
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HPR and did ask in Fallen or Camp last year if there was any relation between the word radio
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in HPR and radio as in hand radio and your answer was pretty much there's no direct connection
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but they are connected in spirit as it were. Anyway, I hope some of this has been of interest.
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Thanks for listening, goodbye.
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You have been listening to the Hacker Public Radio podcast, at hackerpublicradio.org.
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Today's show was contributed by a HPR listener like yourself.
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If you ever thought of recording a podcast, then visit the HPR site to find out how easy it really is.
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Hosting for HPR has been kindly provided by anhonesthost.com, the Internet Archive, rsync.net, and the HPR Community Content Delivery Network.
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Unless otherwise stated, today's show is released under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.
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