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Recommended reading: KonCEPT page 237-259 (Chapter 10,11,12)

This list might need to be updated with regards to what the certification tests.

The legal stuff is translated by -JKK who is not a lawyer… it may not be accurate.

Intermodulation (Splatter)

Over-driven power amplifier distorts the signal. Increased bandwidth. Solved by using less power.

Distortion

For example leakage of signal along outside of coax can cause feedback and amplitude variations. Really unclear definition

Morse key snap (Nyckelknäppar)

Unfiltered CW has sharp flanks in the time domain waveform → snapping sound → too large bandwidth

Harmonic transmission (Övertonsutstrålning)

Your radio also transmits on a harmonic other than the fundamental tone. This harmonic can disturbe others and may be outside the ham radio bands. Add a LP filter on TX, HP filter on RX.

Blocking (Blockering)

A too strong signal nearby overloads the receiver. Not enough dynamic range in a SDR.

LF-detection (LF-detektering)

Other electronics “detects” the RF signals and demodulates them to a low frequency. ex the stories from Radiomotet Göteborg where radoio was heard when a skillet was placed on a stove.

Can be reduced by preventing HF from propagating along the outside of a coax cable with a ferrite or similar.

WE ARE NOT ALLOWED TO PUT FILTERS INSIDE CE-CERTIFICATION EQUIPMENT! This removes the CE-CERTIFICATION

Electric shock: U=RI, R varies with voltage and reduces as a function of voltage from approximately 75V.

High electromagnetic field strengths can cause health problems. And disturb pacemakers.

If you use a transmitter, cell phone and so on and someone gets problems with heart or lungs you MUST stop transmitting immediately.

It is not allowed to cause high electromagnetic field strength in a public place

It is not allowed to transmit with too high power.

Power limits come in several forms.

EIRP = effective isotropic radiated power. Max 1W EIRP→ output power • Antenna gain= 1 W,

ex. 10 mW output power * 20 dBi (x100 in linear scale) antenna gain = 1W

P.E.P = Peak emitted Power → 1W P.E.P = max peak value for signal = 1W.

If you have adequate knowledge concerning electrical safety you are allowed to change:

• a switch (elkopplare (strömbrytare)) for maximum 16A 400V.
• change a receptacle (anslutningsdon (vägguttag, lamputtag, stickpropp, skarvuttag eller liknande) for maximum 16A 400V.
• change light fixture in a dry, non flammable area in a residence area
• install, change or repair a >50V(starkströmsanläggning) that is included in a <50V protection circuit (skyddsklenspänningskrets) with nominal voltage of maximum 50V and power lower than 200VA(almost watts) and a current limited by a fuse of maximum 10A.
• Change fuses
• change light source
• Repair apparatuses
• Make and repair device cables and extension cords.

REMEMBER! Authorized installer shall be hired for work in permanent installations.

This one i cannot translate accurately. (Nybyggnad, förändring eller reparation av starkströmsanläggning, fast anslutning av elektrisk utrustning till en starkströmsanläggning eller att koppla loss fast ansluten elektrisk utrustning från en starkströmsanläggning, klassas som elinstallationsarbete och får endast utföras av person som har auktorisation som elinstallatör eller av yrkesverksam som omfattas av ett elinstallationsföretags egenkontroll. )

Regular citizens may own transmitters, but are forbidden to transmit.

Everyone may purchase a ham radio but only licensed may use the “push-to-talk” button.

This does not apply to jammers… these are totally forbidden to own.

https://www.pts.se/sv/privat/radio/utrustning/forbud-mot-storsandare/

Explain CE-marking. Not China Export.

Radioutrustningslagen SFS 2016:392

Lagens tillämpningsområde och definitioner anger att lagen inte omfattar radioutrustning som används av radioamatörer för amatörradiotrafik, under förutsättning att utrustningen inte tillhandahålls på marknaden. Radioutrustning som används av radioamatörer för amatörradiotrafik ska inte anses tillhandahållen om det är:

• radiobyggsatser som är avsedda att byggas samman och användas av radioamatörer
• radioutrustning som har modifierats av radioamatörer för att användas av radioamatörer
• utrustning som har konstruerats av enskilda radioamatörer för experimentella och vetenskapliga ändamål i samband med amatörradio
• Detta innebär att du som radioamatör, utöver vanlig elektronik, får bygga och använda en radioutrustning. Du är då ansvarig för att den utrustning du byggt är säker att använda och inte orsakar störningar.

This law above means that you may do the following!

• Build a radio from a kit that designed to be constructed by ham radio operators
• use a radio that has been modified to be used inside the ham bands.
• Transmit with things for experimental and scientific purposes in the ham bands.
• You may construct/design/build and use radio devices that may be connected to high voltage. YOU are responsible that they do not cause interference. YOU are responsible that the device does not cause any sort of harm to a persons devices and pets (you may connect it to the power grid!)

This law above means that you may NOT do the following!

• Build a transmitter for usage outside the ham bands.
• Modify a transmitter for usage outside the ham bands.
• Modify a CE-Marked transmitter for usage outside the ham bands.
• Restore a CE-Marked transmitter to its orignial form after it has been modified for usage outside the ham bands.
• Mount a filter inside a CE-marked apparatus.

Use Ground Fault Protection (jordfelsbrytare)!

Ground fault protection is an automatic switch that quickly disconnects power when the current entering the device and the current leaving the device are different. This can happen when there is a ground fault that cause current to flow into the safety ground/chassis of the device.

Ground fault protection protects you from the following isolations and ground faults.

• If the chassis of a device is connected to live voltage.
• If you touch live voltage and ground at the same time.
• If the outlet lack safety ground
• If you use a device wrongly in a wet area
• If you install the device wrong
• If the device cable is damaged
• To reduce the risk of fire

Ground fault protection does not protect against currents flowing from phase to neutral conductor or phase to phase (three-phase). Ground fault protection shall not be a replacement for protection grounding, but can under certain circumstances increase the protection from protection grounding. Ground fault protection is required in new installations. It is reccomended to install Ground fault protection in old buildings.

• The chassis shall be adapted for the device and not be openable without tools.
• The chassis shall have ventilation holes to prevent overheating. Observe that live parts shall not be reachable from the ventilation holes.
• The chassis shall not be hot enough to hurt human or property
• If the chassis is to be connected to the grid and is made from conductive material the chassis and parts that can fail as a short shall be connected to protective ground.
• The AC cable for grid connection shall be adequately strain relieved that also protects from cable wear where the cable leaves the chassis.
• Components in the device shall be dimensioned for the correct power, voltage, current levels and and heat generated in the device. A tip is to have good thermal margins since that leads to increased lifetime and safety margins.
• The device shall be equipped with a correctlyt dimensioned fuse to protect against shorts and over-loads.
• Grid connected devices shall be equipped with two-pole switches. (fuse and neutral)
• Live parts inside the device shall be equipped with touching protection to protect against accidental touches.
• Components in the device shall be fixed in position at suitable internal distances so that the risk of disturbances, sparks, short circuits and overheating is minimized.
• Cables and conductors for high voltage shall be protected against hot components, wear, sharp corners and be separated physically from low voltage sections and signals.
• Always have bleeder resistors in parallel with “big” capacitors so they are discharged when power is disconnected.
• Always use Ground fault protected outlets.

Important for the test!

• Overheating
• High voltages
• Large currents
• Place antennas out of reach for unauthorized
• Charged capacitors
• Lightning
• Antennas and antenna cables can never be protected from lightning strikes. Observe that it is not ok to connect to the buildings lightning protection (åskledare) this will invalidate home insurances

During repair the device shall be powered off. Before starting working

1) turn off the device power swithch

2) Unplug the power cable (double safety)

If trimming or fault finding with live voltage is required follow the following,

• Do not work when tired or unmotivated
• Make sure to not get electrocuted. If possible work with one hand and keep the other hand away from the device. Preferable in your back pocket!
• Don't wear (wired) headphones. Use speaker for trimming by ear.
• Don't work alone with live devices. Show the other person where the power switch is located. It is preferable if they know how to assist with electrocution injuries.

Even though the voltage is low for lead acid batteries they can deliver large short circuit currents. Remove rings, watches and similar when working with them. Use isolated tools when working with battery poles.

Be aware of the electrolyte in lead acit batteries. It is highly corrosive.

Be aware of the explosion risk from hydrogen released from charging a battery which can send acid into eyes.

Modern Lithium (Li<>) batteries are incredibly energy dense. These can catch fire with high temperatures and should be treated carefully. Be careful not to overcharge!