TL;DR: Your mews must be escape-proof (secured door, no gap > 1 inch), weatherproof, predator-resistant, and ventilated. The minimum inside dimensions for an apprentice bird are 8 × 8 × 6 feet. Perches must be appropriate to the species. You will be tested on all of this.

What is a mews and why is it regulated?

A mews is an enclosed housing structure for a falconry bird, used when the bird is not actively being flown or trained. Federal regulations under the Migratory Bird Treaty Act (MBTA) require falconers to provide adequate housing for raptors, because raptors are federally protected species even in the hands of a licensed falconer. The regulations set minimum standards that states must adopt or exceed.

The minimum facility requirements for an apprentice-class bird (a Red-tailed Hawk or American Kestrel) are:

• Inside dimensions: At least 8 feet × 8 feet × 6 feet (length × width × height)
• Construction: Solid sides or covered wire/netting
• Door: Must be fitted with a secure latch that cannot be opened by the bird from inside
• Gap size: No gap, crack, or opening larger than 1 inch — to prevent escapes and bar entry by predators

These numbers are tested directly on the apprentice exam.

What is a weathering area?

A weathering area is a separate, secure outdoor space where a falconry bird can be tethered to a perch and exposed to sun, wind, and natural light — conditions that benefit feather condition and behavior. It must be:

• Fully enclosed with netting or wire
• Covered to prevent predator access from above (hawks, owls, raccoons)
• Free of any gap larger than 1 inch
• Located where the bird is protected from domestic animals

Weathering is a regular part of falconry husbandry. A bird that is properly weathered maintains better feather condition and is less likely to develop behavioral problems from confinement.

What perch types are used in falconry?

Perch choice depends on the raptor species. The two main categories are block perches and bow perches.

Block perches are cylindrical or tapered wooden or padded posts. They are used primarily for falcons — birds with a naturally upright posture that rest most comfortably on a rounded, elevated surface. The block mimics a rocky outcrop or cliff ledge.

Bow perches are semicircular perches, often made of metal rod padded with Astroturf or leather. They are designed for hawks (buteos and accipiters) and harriers, which prefer to wrap their feet around a curved surface. A Red-tailed Hawk in apprentice training will typically use a bow perch.

Using the wrong perch type for a species can cause foot problems and behavioral stress. The exam will ask you to match perch type to bird type.

Exam tip: Falcons → block perch. Hawks → bow perch. This is one of the most reliably tested pairings on the apprentice exam.

What are jesses, leashes, and swivels?

These are the three primary tethering components used whenever a raptor is on a perch or carried on the fist.

Jesses are short leather (or synthetic) straps attached to the bird's ankles. Traditional mews jesses have a slit for attaching a swivel; field jesses (also called slitless jesses) have no attachment slit and are used when flying free. The distinction matters: mews jesses can catch on branches and cause injury if worn in the field.

Swivels connect the jesses to the leash and prevent twisting. A bird that twists repeatedly against a swivel would otherwise tighten the jesses and potentially injure its ankles.

Leashes attach the swivel to the perch. Leashes must be long enough to allow the bird to stand comfortably and bate (jump off the perch) without hanging — but short enough to prevent contact with the ground or other surfaces that could cause injury.

What are the hood and glove used for?

A hood is a leather head covering that blocks the bird's vision, reducing stress and preventing the bird from bating toward visual stimuli. Hooding is a skill that requires patience and consistent practice. When hooding a newly acquired raptor — such as a first Red-tailed Hawk — the approach should be patient, calm, and methodical. Rushing the process causes fear responses that set back training.

A falconry glove (gauntlet) protects the falconer's hand and wrist from the bird's talons during carrying and feeding. For large birds like Red-tailed Hawks, a heavy glove is essential.

What is a lure and when is it used?

A lure is a weighted object — often a padded leather pouch or dead prey tied to a cord — used to recall a bird and condition it to return to the falconer. For falcons, lure flying is the primary conditioning and recall method. The lure is especially useful for conditioning falcons because it mimics aerial prey and builds the flight muscles and instincts needed for hunting.

Live lures (live tethered prey animals) are reserved only for true emergencies and are generally prohibited under normal training. This is directly tested: the exam asks when live lure use is acceptable, and the answer is true emergencies only.

Frequently asked

What are the minimum inside dimensions of a mews for an apprentice bird?

The federally required minimum for an apprentice raptor mews is 8 feet × 8 feet × 6 feet (length × width × height). States may require larger dimensions.

What is the maximum gap allowed in a mews structure?

No gap, crack, or opening in the mews may exceed 1 inch in any dimension. This prevents both escapes and predator entry.

Why are field jesses different from mews jesses?

Field (slitless) jesses have no attachment slit, so they cannot snag on branches or brush when the bird is flying free. Mews jesses have a slit for attaching the swivel during tethering but must be swapped for field jesses before releasing the bird to fly.

TL;DR: Voltage (V) = Current (I) × Resistance (R). Know this triangle, the units (volts, amperes, ohms), and how to rearrange it for current (I = V/R) and resistance (R = V/I). That covers the bulk of Ohm's Law questions on the Technician exam.

What is Ohm's Law?

Ohm's Law states that the voltage across a conductor is directly proportional to the current flowing through it, as long as temperature remains constant. The formula is:

V = I × R

Where:

• V is voltage, measured in volts (V)
• I is current, measured in amperes (A) — often shortened to "amps"
• R is resistance, measured in ohms (Ω)

The law was formulated by German physicist Georg Simon Ohm in 1827 and remains foundational to every branch of electronics, including amateur radio.

What do voltage, current, and resistance actually mean?

Understanding what each term represents makes the math stick.

Voltage is electrical pressure — the force that pushes electrons through a circuit. Think of it like water pressure in a pipe. Higher voltage means more push. A 12-volt car battery provides more push than a 1.5-volt AA cell.

Current is the flow of electrons — how many pass a given point per second. Continuing the water analogy, current is the flow rate. More current means more electrons moving. Current is what does work: it lights LEDs, drives speakers, and transmits RF signals.

Resistance is opposition to current flow. Every wire, component, and connection has some resistance. A resistor is a component specifically designed to limit current. Higher resistance means less current flows for a given voltage.

How to use the Ohm's Law triangle

A common memory aid is the Ohm's Law triangle: imagine a triangle divided into three sections. Put V on top, and I × R on the bottom (I on the left, R on the right). Cover the quantity you want to find, and the remaining two show the operation:

• Cover V: V = I × R
• Cover I: I = V ÷ R
• Cover R: R = V ÷ I

This works for every rearrangement. For the Technician exam, you need all three.

Exam question types you will see

The NCVEC Technician question pool (T5D subelement) tests Ohm's Law directly. You will be asked to calculate one of the three quantities given the other two. Here are the patterns:

Calculate current: "What is the current in a circuit with 12 volts and 4 ohms resistance?"

I = V ÷ R = 12 ÷ 4 = 3 amperes

Calculate resistance: "What resistance is needed to limit current to 0.5 A from a 12 V source?"

R = V ÷ I = 12 ÷ 0.5 = 24 ohms

Calculate voltage: "What voltage is across a 10 Ω resistor carrying 2 A?"

V = I × R = 2 × 10 = 20 volts

Exam tip: Always watch the units. The exam uses volts, amperes (amps), and ohms — not milliamps or kilohms unless stated. If a value is given in milliamps (mA), convert to amps first by dividing by 1,000 (e.g., 500 mA = 0.5 A).

Power: the fourth quantity

The Technician exam also tests electrical power, which uses Ohm's Law as a building block. Power is measured in watts (W) and uses the formula:

P = V × I

Combined with Ohm's Law, this gives additional forms:

• P = I² × R
• P = V² ÷ R

A typical question: "What is the power consumed by a 50 Ω load fed 100 V?"

P = V² ÷ R = 10,000 ÷ 50 = 200 watts

The units you must know

Memorize these cold — the exam will test the units separately from the formulas:

• Voltage — Volt (V)
• Current — Ampere (A)
• Resistance — Ohm (Ω)
• Power — Watt (W)

Electrical current is measured in amperes. Electrical power is measured in watts. These are standalone T5 questions that don't require calculation.

Frequently asked

What does "electromotive force (EMF)" mean on the exam?

EMF is another term for voltage — the force that causes electrons to flow. The Technician pool asks: "What is the electrical term for the electromotive force (EMF) that causes electron flow?" The answer is voltage.

What is the name for the flow of electrons in a circuit?

The flow of electrons is called current. This is tested directly in the T5 subelement as a standalone definition question.

Why does amateur radio care about Ohm's Law?

Every RF circuit, feedline, antenna system, and power supply in your station obeys Ohm's Law. Understanding it lets you calculate antenna feedpoint impedance, size fuses correctly, troubleshoot power supply issues, and match transmitter output to antenna systems. It's not just an exam topic — it's the foundation of every hands-on radio project.

TL;DR: Symmetric encryption uses the same key to encrypt and decrypt (fast, used for bulk data). Asymmetric encryption uses a key pair — a public key to encrypt, a private key to decrypt (slower, used for key exchange and digital signatures). Most real systems (HTTPS, TLS) combine both.

What is symmetric encryption?

Symmetric encryption uses a single shared key for both encryption and decryption. Anyone who possesses the key can encrypt or decrypt the data. This makes symmetric encryption extremely fast and efficient for encrypting large volumes of data — which is why it's the default for disk encryption, file encryption, and the bulk-data phase of TLS sessions.

The dominant symmetric algorithm on the Security+ exam is AES (Advanced Encryption Standard). Key facts about AES:

• Symmetric (same key for encrypt and decrypt)
• Block cipher (operates on fixed-size blocks of data)
• Key sizes: 128, 192, or 256 bits — larger keys are more secure
• NIST-approved and used in most modern encryption standards, including WPA2/WPA3 Wi-Fi security

Other symmetric algorithms you may encounter: DES (outdated, 56-bit key, no longer considered secure), 3DES (Triple DES, a stopgap improvement on DES, also being retired), and Blowfish/ChaCha20 (less common on the exam).

Exam tip: The Security+ exam frequently asks to identify symmetric vs. asymmetric algorithms. AES = symmetric. RSA, ECC, and Diffie-Hellman = asymmetric. This is one of the most commonly tested distinctions in the cryptography domain.

What is asymmetric encryption?

Asymmetric encryption uses a mathematically linked key pair: a public key and a private key. Data encrypted with the public key can only be decrypted by the corresponding private key, and vice versa. The public key is freely shared; the private key is kept secret by its owner.

This property enables two fundamental security operations:

• Encryption: The sender encrypts with the recipient's public key. Only the recipient (who holds the private key) can decrypt.
• Digital signatures: The signer encrypts a hash of the message with their private key. Anyone can verify the signature using the signer's public key, confirming both authorship and integrity.

Asymmetric algorithms are significantly slower than symmetric ones for bulk data. For this reason, they're used for key exchange and authentication — not for encrypting large files.

Common asymmetric algorithms for the SY0-701 exam:

• RSA — most widely known; used for key exchange and digital signatures; key sizes typically 2048 or 4096 bits
• ECC (Elliptic Curve Cryptography) — provides equivalent security to RSA with much smaller key sizes; more efficient, used heavily in mobile and IoT; underlies ECDSA (for signatures) and ECDH (for key exchange)
• Diffie-Hellman (DH) / ECDHE — a key exchange protocol (not encryption), used to establish a shared secret over an insecure channel; ECDHE adds ephemeral keys for perfect forward secrecy

How do symmetric and asymmetric encryption work together in TLS?

This is one of the most important real-world scenarios for the exam.

When your browser connects to an HTTPS website, TLS performs a hybrid operation:

1. Asymmetric phase (key exchange): The server presents its certificate (containing its public key). The browser uses asymmetric cryptography (e.g., ECDHE for key exchange, RSA/ECDSA for authentication) to establish a shared session key without transmitting it over the network.

1. Symmetric phase (bulk data): Once the session key is established, all subsequent data (the actual HTTP traffic) is encrypted with AES using that shared session key. AES is fast enough for real-time data.

The result: asymmetric cryptography solves the key distribution problem; symmetric cryptography provides the speed needed for actual data transfer. Neither alone is the complete solution.

What is perfect forward secrecy (PFS)?

Perfect forward secrecy means that if a server's long-term private key is later compromised, past session recordings cannot be decrypted retroactively. It is achieved by using ephemeral key pairs (new ones for each session) during key exchange — which is what the "E" in ECDHE means. The Security+ exam tests PFS as a feature of TLS 1.3 and as a reason to prefer ECDHE over static RSA key exchange.

Digital signatures and certificate authorities

Asymmetric cryptography is the foundation of digital signatures and the Public Key Infrastructure (PKI) that makes HTTPS trustworthy:

1. A certificate authority (CA) digitally signs a server's certificate using the CA's private key.
2. Your browser trusts the CA's public key (pre-installed in the OS/browser trust store).
3. The browser verifies the server's certificate using the CA's public key, confirming the server's identity.

This chain of trust — from the root CA down to the server certificate — is PKI. Understanding it is essential for the Identity and Access Management and Cryptography domains on SY0-701.

Frequently asked

Which encryption algorithm is symmetric?

AES is symmetric. It uses the same key for both encryption and decryption. This is the most tested symmetric algorithm on Security+.

What is the difference between RSA and ECC?

Both are asymmetric. RSA relies on the difficulty of factoring large prime numbers and uses larger key sizes (2048+ bits). ECC relies on elliptic curve discrete logarithm problems and achieves equivalent security with much smaller keys (256-bit ECC ≈ 3072-bit RSA), making it more efficient for constrained environments like mobile devices.

Which protocol uses TLS to encrypt web traffic?

HTTPS uses TLS (Transport Layer Security) to encrypt web traffic, protecting data in transit from eavesdropping and tampering. TLS is also used by SMTPS (email) and other application protocols.