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This material, coming into use for various application, has significant potential. The exam cites use in MMICs, Monolithic Microwave Integrated Circuits at the highest frequencies.
If you want to read more, this material is used in High-electron-mobility transistor (HEMT), aka heterostructure FET (HFET), aka modulation-doped FET (MODFET). Other applications are in power control circuitry for electric vehicles, and a range of high intensity LEDs. The examiner sees the aforementioned high electron mobility as an "important" property to make it useful at UHF and beyond.
Gallium arsenide (GaAs) also has high electron mobility. They are used in FET amplifiers at UHF, and up to perhaps 12 GHz. These include receive amplifiers and small power amplifiers (a 23 cm hand-held is typically 1 watt).
The TOKYO HY-POWER HL-35V 144 MHZ 2m RF Power Amplifier included a switchable GaAs FET receive amplifier, as did the Dick Smith branded version I owned.
MMICs are Monolithic Microwave Integrated Circuits, which operate as signal and power amplifiers across a set bandwidth, with consistent gain. They typically have have 50 ohms input and output impedance.
Power is typically applied to the output, via a resistor or inductor. The inductor conducts DC power, while preventing RF or microwave energy going to the power supply.
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| Image and diagram indicating the use of a MMIC, by WikiMedia user: Appaloosa. This triangle symbol is used for single-input / unbalanced input amplifiers. |
The MSA-0686 is in a micro-X case, also coded SOT-86 and "86 plastic package"; micro-P or MP86 (E) is a compatible size. It has an upper limit of 800 MHz. Devices in the same format, such as the MAR-6, can be used in TV masthead amplifiers, or in receive amplifiers for bands such as 23 cm. Both mentioned are silicon.
A preamplifier is useful in weak signal stations, especially when placed as close to the antenna feed-point as practical. This is especially relevant for EME (moonbouce) stations. However, adding a preamplifier to a receive signal chain always adds a small amount of noise.
It is the decibel relationship of the the input and output signal-to-noise ratios.
You can see the maths at: Wikipedia: Noise figure. Many EME pages have information on preamplifiers and signal and noise levels, etc.
The examiner uses 0.5 dB, improved from the previous pool's 2 dB.
Several hundred euro buys a 0.68 dB NF unit, with others claiming as low as 0.19 dB.
Off the exam, radio telescopes, NASA JPL's Deep Space Network, and a few specialised satellite reception stations use cryogenically cooled receivers. They typically use liquid helium, chilled to single digit Kelvin temperatures. These greatly reduce the noise figure.
These amplifiers will be destroyed if exposed to RF power from a transmitter. They must either include RF triggered relays, or be sequenced to be removed from the circuit. Options include switching a power amplifier in, in its place, and obviously in the opposite direction.
You can also build one using a GaAs FET: HADARC: VHF/UHF Preamp, using the newer MGF1402B. The noise figure should be below 0.5 dB. It was originally from the Eastern and Mountain Districts Radio Club, Inc.
Dual In-line Packages are often used to house integrated circuits. They are termed DIP, or occasionally, DIL. They have a row of leads, usually spaced at 0.1" or 2.54 mm down each side. Plastic is most common, although ceramic material can be used, which is better for dissipating heat.
They are most usually mounted by inserting the pins through a printed circuit board, and soldering them in place. Socketing is an alternative, where the socket is soldered into the board. Strip boards, including the Vero brand, and other prototyping boards are designed to hold ICs. There are also push-in "breadboards", to allow prototyping or classroom use. These have capacitance between the metal strips joining the holes. LEDs, voltage regulators (TO-220 size), and some capacitors are deigned to fit boards with this spacing. TO-92 cased components have and option of having leads factory formed to this spacing.
While there are FM broadcast band receiver ICs in these packages, at UHF, the length of the pin, and the internal conductor leading to the silicon die becomes too long.
Opto-couplers are also mounted in these packages, as are arrays of resistors or Darlington transistors.
The width is 0.3" in lower pin counts, 0.6" in high counts (40 pins for the Z80 and 8080, fewer for many EPROMS), and 0.9" wide 64 pin monsters for the 68000 processor. 0.3" wide 24 and 28 pin items are termed "SkinnyDIP". CDIP or CerDIP may be used to specify Ceramic DIP, be they white or dark grey. PDIP specifies plastic, black except for the often white opto-couplers / opto-isolaters.
ShrinkPDIP have a 0.07 inch or 1.778 mm lead pitch.
Resistor arrays are often in fawn or blue packages, or occasionally white. Small relays and switches are also available in DIP sizes.
Resistors and some other devices are in SIL packages. These often have 8 resistors linked to one pin on the end, to provide pull-up or pull-down. Others link 1-2, 3-4, ... 9-10. Some ICs also come in this package, especially those with a heatsink tab.
Quad-In-Line packages (QIP or QIL) were popular in the 1980s in high-end equipment, with leads leaving each side with a 0.05" spacing, half bending down almost immediately, the ones in between extending an additional 0.1" before being bent down.
Almost all modern commercial electronics is built using surface mount components. In many cases the components are significantly smaller, and lower in profile, than through-hole ones. Track and lead lengths can be much shorter than on through-hole boards, making the useful frequency extend into the UHF range.
Abbreviations are SMT (Surface Mount Technology) and SMD (Surface Mount Device).
Some hobby electronics is moving to this too, especially when many ICs are only available in SM. SOIC (Small Outline IC) have a 1.27 mm or 0.05" spacing, and are not too difficult to hand solder.
Surface mount has been used since the early 1960s, with the Flatpack format used in things such as 53 and 54 series logic, for military and space applications. This has a 0.05" lead spacing. Welding was often use in preference to soldering!
To further extend the frequency range into the microwave region, microstrip boards have tracks with tuned widths, a specific distance above a ground plane, to ensure the correct impedance.
Photoconductive materials, exhibit a considerable reduction in resistance when illuminated, otherwise termed an increase in conductivity. It appears the examiner is interested in photodiodes, or perhaps photostransistors, as they are indicate that photoconductive devices are most commonly made using a crystalline semiconductor. The type of semiconductor used determines the spectrum detected.
An alternative material used is CdS, as used in light dependent resistors (LDRs), which only appears in a spoiler on a PV question. They do NOT use a junction.
You should remember from earlier papers that conductance is the inverse of resistance, and resistance the inverse of conductance. Mathematically it is expressed as G = 1 / R and R = 1 / G.
These are the same thing. The dual names are because they can couple a signal between two circuit sections, while electrically isolating them. Other terms are photocoupler, or optical isolator. They can be used in low voltage equipment controlling mains powered circuits. They have also be used between mains powered computer equipment and telecommunications equipment, to remove the risk of dangerous voltages appearing on the 'phone line, where they could harm technicians and line workers, where a number can be used to pass signals and control signals in both directions. They may also be used in medical equipment connected to the human body, such as ECG / EKG and EEG systems.
Common types consist of a LED, often a infra-red, which illuminates a photodiode or phototransistor. Current into the LED results in a small voltage or the conduction of the phototransistor on the output side.
Historically a neon or lamp and a CdS light dependent resistor provided an analogue level, or even audio. There are apparently also photovoltaic versions.
Read more at: Wikipedia: Opto-isolator
They are also one option for bringing the state of a mains voltage line into a processor circuit. You can make one by using a neon (with a resistor) and a CdS cell or other device facing each other within black heatshrink. Obviously mains rated wires, etc, need to be used.
What these provide is also termed "galvanic isolation". Read more at: Wikipedia: Galvanic isolation
Optical fibre can provide very high voltage isolation, depending on its length. They are used in some special telephones in electrical substations. And while "fraudband" customers in the Blue Mountains regularly have their VDSL copper pair connected modems destroyed during lightning storms, those in areas where Labor's original pure fibre NBN was first rolled out have no such problems.
Wandering off this section, small transformers are used in modems connected to telephone lines to pass audio frequency signals. Low cost ones can be used between PCs and radios, with an optoisolator in the keying circuit. Higher priced mu-metal shielded ones may be used in active or passive "DI-boxes" linking the unbalanced output of a guitarist's (or electric harp player's) amplifier, or from the instrument directly, to a long balanced cable going to a mixing desk. Ditto form electronic keyboards, and computers located at the stage, rostrum, or pulpit rather than near the desk.
Traditional relays can also provide isolation, and were used in things such as the line relay in dial-up modems. A small relay with a mains voltage coil can also provide an input to a control system. For AC current transformers allow isolated current measurement, but note that an unterminated CT can have a lethal voltage on the meter terminals; a Hall effect device does this for AC or DC, and is safer.
From the answer below, these use semiconductors to implement the functions of an electromechanical relay. Some use optical coupling to operate a Triac, but many use a small transformer to power more complex switching including MOSFETs. "Zero crossing" switching is also an option, reducing current spikes at switch on. Most are rated for AC mains voltages. Specific products are available for DC.
Size range from DIP and single-in-line PCB mount packages rated at a few amps to small and large DIN Rail mount industrial units. The most popular size for single phase units is 57.2 x 44.5 mm, and 19 to 30 mm high, especially if a safety cover is provided. Ratings are from 10 to 125 amps, and 240 to 690 volts. The minimum voltage is from 24 to 48 volts AC. One I saw advertised is rated 60 v DC at 100 amps. These should generally be mounted on a heatsink. Three phase units are larger. Many units have a 3 to 32 volts DC input range. Termination is often via screws for crimped on screw eye terminals, although push-on tabs are an option.
Crydom make dual SSRs in a single module to switch split phase power, such as for high tension transformers in a tube linear amplifier, which are started after a delay to allow the filaments to warm up. Just parallel the inputs. It is also possible to use two SSRs for this. If you live in a 240 volt (star voltage) country you can use the two halves independently, say for the transformer for the filament(s), then the one for the high tension transformer. That said, there is little need to use a relay / timer for the heaters. Also, I am not entirely sure using SSRs to soft start the HT transformer via resistors is the best option.
SSRs with mains or lower voltage AC input are available. Also, some SSRs do not provide isolation.
Online sales may be for fake devices, so purchase from a reliable source; or if money is tight, maybe one pulled from old equipment.
Wandering even further off the paper, I am not a fan of Crydom's suggestion to use the double one above to control a three phase motor, as all windings remain at mains potential when off. The exception would be corner grounded three phase. Maybe one day you will need to control a large fan in a commercial two-way or broadcasting site.
While various materials are used for solar cells, silicon is used on standard panels you might use for a field day or emergency activation.
When light strikes the material electrons are forced to move, creating current. Each cell only generates 0.5 volts (or slightly more, at 0.55 volts), so many need to be places in series to generate useful voltages. Open circuit voltage is often significantly above the voltage of the battery to be charged.
These have moved from an expensive way to generate power, used in things like remote microwave repeater stations to the cheapest way to generate household or grid scale power, and are rapid to install. While a nuke plant may take 50 years from proposal to first synchronisation to the grid (yes, Hinkley Point C was proposed in 1981, and with a lot of luck may come online in 2031), grid scale solar fields can be online within a year or so, and provide shade and often improved grass for sheep grazing on otherwise marginal land.
Single large panels for 12 volt systems are around US$1 per watt, plus tariffs and taxes. In Australia they are around A$1.50 including GST. Hinged panels, flexible, and lightweight are more, and a charge controller is needed. Small panels are a few dollars per watt.
While panels for Ham use likely only output tens of volts when open circuit, rooftop ones can output hundreds, especially when in a series string - they may be "just DC", but they could be lethal if mishandled. That said, industry standard connectors are touchproof in male and female form.
Remote repeaters use panels, but perhaps your club can get a grant to make your city based repeater grid independent, also saving on or removing power charges and expensive daily supply charges. MMPT charge controllers are typically used in such cases.
The University of New South Wales in Sydney, Australia is one of the global leaders in solar, including ones under 10 cm in diameter which work by having light concentrated on them using many large mirrors. The expanding Tindo are making conventional panels in South Australia, and bi-facial panels are becoming popular at solar farms, as they catch morning and evening (late afternoon) sun for those consumption peaks, while allowing cropping and other agriculture (termed agri-voltaics).
The US's research agency is the National Renewable Energy Laboratory, which was established as the Solar Energy Research Institute under the Solar Energy Research, Development and Demonstration Act of 1974, passed by the Democratic 93rd Congress during Gerald Ford's term. On December 1, 2025 it was renamed "National Laboratory of the Rockies" without Congressional approval, perhaps a political move to remove the term "renewable energy", although it does not appear to have been nobbled yet, even if the Secretary of Energy is a rabid fracker, being moved in from the fossil fuel industry, rather then being a highly experienced public administrator like his predecessor. Meanwhile the GQP members are introducing pointless Bills to try to trash solar, in favour of their fossil fuel donors. Perhaps they should be made to wear prominent Peabody or Exxon patches like a racing car driver, to show who they really work for.
Even if developments mean CdTe becomes more common, the answer will remain Silicon on the paper for the remainder of this exam period.
Pro tip: Most lighter-socket style USB chargers are electrically very noisy, and if connected to your main solar and battery system used for field operations can interfere with radio reception, so having a battery with a fused lighter outlet and PowerPoles, which can be separated from the system is a good idea. Only Aviation grade chargers are clean, and interestingly, the "Pilot C O CHARGER" which includes a carbon monoxide detector are the least costly, although there are no direct claims to its characteristics.
These are the actual questions from the Extra licence exam pool, as published by the NCVEC.
E6E01
Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?
A. Higher noise figures
B. Higher electron mobility
C. Lower junction voltage drop
D. Lower transconductance
GaAs material has higher electron mobility, answer B.
E6E02
Which of the following device packages is a through-hole type?
A. DIP
B. PLCC
C. BGA
D. SOT
DIP stands for Dual-In-Line Package (also called DIL), these have been used for ICs, resistor arrays, and Darlington arrays for many decades, and are through-hole components, answer A.
The remainder are surface-mount, although PLCC and BGA can be socketed.
E6E03
Which of the following materials supports the highest frequency of operation when used in MMICs?
A. Silicon
B. Silicon nitride
C. Silicon dioxide
D. Gallium nitride
This is the relatively new material, Gallium Nitride, GaN, answer D.
E6E04
Which is the most common input and output impedance of MMICs?
A. 50 ohms
B. 300 ohms
C. 450 ohms
D. 75 ohms
The standard RF communications system impedance is 50 ohms, and this applies to MMICs, answer A.
E6E05
Which of the following noise figure values is typical of a low-noise UHF preamplifier?
A. 0.5 dB
B. -10 dB
C. 44 dBm
D. -20 dBm
0.5 dB, answer A.
Interestingly this has improved over the figure supplied 4 years earlier.
E6E06
What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?
A. The ability to retrieve information from a single signal even in the presence of other strong signals
B. Extremely high Q factor and high stability over a wide temperature range
C. Nearly infinite gain, very high input impedance, and very low output impedance
D. Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
Unlike simple RF transistors, MMICs simplify RF device design by having controlled gain, a low noise figure, and constant input and output impedance over the design frequency range, answer D.
Answer C applies to operational amplifiers, used for audio and similar signals discussed later in the paper.
E6E07
What type of transmission line is used for connections to MMICs?
A. Miniature coax
B. Circular waveguide
C. Parallel wire
D. Microstrip
Microwave circuit boards, including those using MMICs, use microstrip construction, answer D.
E6E08
How is power supplied to the most common type of MMIC?
A. Through a capacitor and RF choke connected to the amplifier input lead
B. MMICs require no operating bias
C. Through a resistor and/or RF choke connected to the amplifier output lead
D. Directly to the bias voltage (Vcc) lead
Power is supplied via a resistor and/or RF choke, connected to the amplifier output lead, answer C.
This can be useful as power can be fed to a masthead amplifier via the coaxial cable from the shack, or from a wall-wart power supply near a TV.
E6E09
Which of the following component package types have the least parasitic effects at frequencies above the HF range?
A. TO-220
B. Axial lead
C. Radial lead
D. Surface mount
Surface mount is most suitable for VHF and UHF circuits, answer D.
E6E10
What advantage does surface-mount technology offer at RF compared to using through-hole components?
A. Smaller circuit area
B. Shorter circuit board traces
C. Components have less parasitic inductance and capacitance
D. All these choices are correct
Surface mount uses components without leads, soldered directly to the PCB, reduces parasitic inductance and capacitance, answer D.
E6E11
What is a characteristic of DIP packaging used for integrated circuits?
A. Extremely low stray capacitance (dielectrically isolated package)
B. Extremely high resistance between pins (doubly insulated package)
C. Two chips in each package (dual in package)
D. Two rows of connecting pins on opposite sides of package (dual in-line package)
These have 2 rows of pins, one down each side of the package, answer D.
The material of the case can be specified - PDIP or CDIP, Plastic or Ceramic. DIL was also used in the past, Dual-In-Line, with humorous overtones, a dill being an unintelligent person.
E6E12
Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?
A. Excessive dielectric loss
B. Epoxy coating is conductive above 300 MHz
C. Excessive lead length
D. Unsuitable for combining analog and digital signals
The lead length, and the internal lead frame connections are excessively long at UHF and up, answer C.
E6F01
What absorbs the energy from light falling on a photovoltaic cell?
A. Protons
B. Photons
C. Electrons
D. Holes
Light striking the photovoltaic material strikes the electrons, causing current flow, answer C.
Read this one carefully, as it is the production of electrical current, which is the movement of electrons. That which causes the movement is present as the second spoiler.
E6F02
What happens to photoconductive material when light shines on it?
A. Resistance decreases
B. Resistance increases
C. Reflectivity increases
D. Reflectivity decreases
Photoconductive implies that conductance increases with light, meaning that resistance decreases when the material is illuminated, answer A.
E6F03
What is the most common configuration of an optoisolator or optocoupler?
A. A lens and a photomultiplier
B. A frequency modulated helium-neon laser
C. An amplitude modulated helium-neon laser
D. An LED and a phototransistor
This couples data or other information between circuits while providing electrical isolation. These typically consist of an LED and a phototransistor, answer D.
The others are just plain silly. Other optical receiving elements may be used.
E6F04
What is the photovoltaic effect?
A. The conversion of voltage to current when exposed to light
B. The conversion of light to electrical energy
C. The effect that causes a photodiode to emit light when a voltage is applied
D. The effect that causes a phototransistor's beta to decrease when exposed to light
This is the conversion of light energy to electrical energy, answer B.
While they can be used as high speed optical receivers, in the vast majority of cases they are used for power production, be it to charge a battery for field or emergency operations, powering a home (ideally with a large sodium ion (Na+), Lithium, or other battery, or at grid scale.
E6F05
Which of the following describes an optical shaft encoder?
A. A device which detects rotation of a control by interrupting a light source with a patterned wheel
B. A device which measures the strength of a beam of light using analog-to-digital conversion
C. An optical computing device in which light is coupled between devices by fiber optics
D. A device for generating RTTY signals by means of a rotating light source
These detect rotation by having a patterned disc interrupt an optical path answer A.
While they can be used for sensing in industrial applications, in Amateur Radio they are used for the tuning knob on transceivers. They were also used ball-based PC mice.
E6F06
Which of these materials is most commonly used to create photoconductive devices?
A. Polyphenol acetate
B. Argon
C. Crystalline semiconductor
D. All these choices are correct
This is a crystalline semiconductor, answer C.
The word "most" calls for a specific answer, making D stupid. Argon is an inert or "noble" gas which emits a pink glow if used in a discharge lamp. It is used in photomultiplier tubes, but these are NOT common compared solid state light and IR detectors. Semiconductor photoconductive devices are used in in the remote control receivers likely to be in the one or several pieces of entertainment equipment in your home; and in the optical mechanisms of CD / DVD / HD-DVD / SACD / BluRay / MD players.
If google's AI summary is to be believed, polyphenol acetates are health promoting compounds present in things like olive oil and tea. (By the way posts warning of the dangers of Canola or "seed" oils are a total fabricationP.
E6F07
What is a solid-state relay?
A. A relay using transistors to drive the relay coil
B. A device that uses semiconductors to implement the functions of an electromechanical relay
C. A mechanical relay that latches in the on or off state each time it is pulsed
D. A semiconductor switch that uses a monostable multivibrator circuit
An SSR uses an optocoupler or transformer based circuit connected to a high current semiconductor to emulate a regular relay, answer B.
The first item is a Hybrid relay, with the German made Pheonix Contact EMG 22-REL/KSR-G and 24/TRN12 EMG 22-REL/KSR-G 24/TRN 5 being examples, working at 12 or 5 volts. They need a supply as well as the switching signal, which must be a positive going DC voltage. Various latching relays exist, as do industrial timers perhaps alluded to in the last distractor.
E6F08
Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits?
A. Optoisolators provide a low-impedance link between a control circuit and a power circuit
B. Optoisolators provide impedance matching between the control circuit and power circuit
C. Optoisolators provide an electrical isolation between a control circuit and the circuit being switched
D. Optoisolators eliminate the effects of reflected light in the control circuit
These provide good electrical isolation between the low voltage circuit, and the mains voltage circuit, answer C.
These are used with thyristors, often triacs, which are solid state devices which are directly switching mains voltages. In alternative cases, where control circuits are at mains potential, the entire circuit MUST be fully insulated from the user. Youtuber "Big Clive" pulled apart and analysed an electrically operated curtain controller which had given someone a shock because the antenna wire was live at 240 volts (the UK voltage)!
E6F09
What is the efficiency of a photovoltaic cell?
A. The output RF power divided by the input DC power
B. The output in lumens divided by the input power in watts
C. The open-circuit voltage divided by the short-circuit current under full illumination
D. The relative fraction of light that is converted to current
This is the fraction (percentage) of light energy converted to electrical energy (power), answer D
The first one is for an RF power amplifier, and might be there to "take out" those who just mindlessly remember answers. And remember, these convert light to power, not the other way around, as an LED or other lamp does.
E6F10 (B)
What is the most common type of photovoltaic cell used for electrical power generation?
A. Selenium
B. Silicon
C. Cadmium Sulfide
D. Indium arsenide
Most ordinary portable, roof-top, and grid scale solar panels are silicon, answer B.
While other materials may come into more widespread use, they are not any of the spoilers, even if one includes one of the mentioned elements. The first was used in early light meters used with cameras (which did not need a cell / battery), and after this pool was written modern tandem cells using it as a layer over a silicon layer were demonstrated. But the answer is still silicon, and will be until changed by the NCVEC.
The mere existence of CdTe cells is currently being used for the coal / gas industry funded Fear, Uncertainty, and Doubt (FUD) brigade, and the gullible who repeat their lies, to scaremonger about solar panels on farms (termed agri-voltaics) which can "save the farm" during drought years.
E6F11
What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?
A. 0.5 volts
B. 0.7 volts
C. 1.1 volts
D. 1.5 volts
These generate half a volt per cell, answer A, so many are placed in series to generate a useful voltage.
Tindo operates in an area needing employment, especially after Holden (makers of the Chev PPV and SS, and Pontiac G8; and the Vauxhall VX8R and Monaro) was shut down, so a win-win situation.
Fracking in the highly damaging process of drilling into shale or coal seams, and injecting secret but toxic chemicals to fracture the seams to emit methane. They frequently leak this potent greenhouse gas. There is certainly nothing "natural" about this gas. There are also major significant risks to vital ground water resources. Unlike clean energy, they force their way into farms, unwanted. Interestingly, Secretaries are among those removed upon the impeachment and conviction of a president. They are also subject to individual impeachment.
For those outside the US the Congress (the House of Representatives plus the Senate) works quite differently to the Westminster system. In the UK and Australian systems government ministers and their departments generating bills (proposed laws), and members of the government party almost always all vote with it, and the opposition and cross bench with or against depending on the subject, or if the hard right "Liberals" are in obstructionist mode (the "NOPEosition" of Tony Abbott). It is only in the Senate where negotiation is needed; at the moment Labor needs either Green or L/NP support on a vote, One Nation is totally irrelevant to the process. The exception to all government members supporting a bill is when a "conscience vote" is permitted, usually around an outdated reading of Leviticus.
In the US major bills are introduced by the party which holds the majority in the House (which may or may not be the party of the president, and which may change at the Mid-term election (mid-terms), which is very likely in 2026.
However, a bill might be the result of say "Moms for Peanut Safety" lobbying local members for a law for better labelling and/or strong consequences for causing harm, one or more of which "sponsors" the bill, giving it H.R. and/or S. number(s). It perhaps becoming "Bipartisan", if support is gained from both sides. It may also have a name such as "Kara's Law" after a child who ate a commercial sandwich or sub with undeclared peanut products, and died. The "Moms" then come to Washington to lobby members, who decide whether children's lives are more important than profits of peanut farmers or peanut processing businesses which may exist in their constituencies; and the profits of companies which use them in their products. Meanwhile the industry donates millions to the "Legume PAC" (Political Action Committee) which funds hit ads against the Bill (oh, the cost to the poor farmers, etc). Industry lobbyists also offer members "donations" for their rejection of the bill. If it gets a vote in the House it may pass, and be sent to the Senate, including for amendment. Or it may die with the ending of a Congress' term, or die in a Committee. The public can also call or email their Representative and Senators to support or oppose the bill. If it passes both chambers it then goes to the president for a signature to become law, although they may have a veto power, depending on the percentage supporting the bill. In a recent case he did for the most utterly petty reason, denying folk in Colorado clean water. (The late, great Jimmy Carter put his family business into a blind trust to avoid the and suggestion of any conflict of interests; someone else totally ignored this concept).
The latter is the case with H.R. 1094/S.459 to overturn HOA antenna bans. It is supported by the Texas HAM PAC. Click on: send-a-letter.org/hoa/
On to: Practical Circuits 1 - Digital circuits & Amplifiers
You can find links to lots more on the Learning Material page.
Written by Julian Sortland, VK2YJS & AG6LE, January 2026.
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