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Like millions of other preppers, I live in the southwest portion of the United States. That affords me the advantage of great scenery, mountaintop views and vast areas of land where I can escape the normal everyday business pressures of life by finding an outdoor area to escape into and reconnect with nature. Those vast open landscapes, however, expose an area that most preppers pay little attention to normally, which is how to communicate over those vast areas of land and communicate off-grid completely when needed.

In case you haven’t already noticed, time after time the news media reports that an experienced hiker, hunter, camper, or outdoorsman was found hurt or later found dead because they couldn’t notify anyone that they needed medical help. So even though their cell-phone worked in town, their departure into the wilderness created their own personal “grid-down” scenario, as their only means of semi-reliable long-distance communication (their cell phone) was made useless by their decision to head into the great outdoors (and way beyond their carrier’s cell-phone range).

As both an amateur Radio operator of 35+ years (and owning a company involved in two-way communications), I agree with most ham radio operators and FEMA officials that the “best” grid-down communication tools (including your own personal grid-down emergency that might arise) normally involve ham radio or satellite phone gear, so let’s look at the various types of communication gear and see how they hold up in a disaster or emergency scenario (and realize that your personal “grid-down” situation will share similar off-grid communication challenges).

Many folks first step into two-way radio frequency (or RF) communications usually doesn’t involve ham radio or satellite phones, sometimes due to their perception of the learning difficulty, or the equipment cost, or even them not understanding how the different radio bands allow hams to “target” our communication ranges (vs. a single band like CB or FRS/GMRS).

I also don’t believe that ham radio is the “only” way for EMCOMM (emergency communications) either, but not because of my Extra Class amateur radio license, it’s because of the vast ham radio infrastructure (located all over the world) available to any licensed ham (plus the relatively cheap cost to jump into either ham radio or satellite communications now).

According to the ARRL (Amateur Radio Relay League), we have just over 22,000 U.S. ham radio repeaters as of January 2015, with thousands more located around the world. Here’s an example of how that existing infrastructure can make a huge difference:

Imagine a disaster that sweeps through an area, wipes out the local electrical grid, takes out the cell tower(s), destroys the local public service repeaters (Fire, Police, etc.), and takes out the local GMRS and ham radio repeaters, plus generally wrecks the community with downed trees, power lines, etc.

So if everything involving local communications is toast (or if you find yourself 25 miles from the nearest cell tower deep in the back country of your state) – what’s the difference between using a small handheld (HT) ham radio vs. a CB, FRS/GMRS, Marine, or MURS radio? Won’t satellite communication be affected as well?

First, the vast quantity of communication options still available to the licensed ham, including more repeaters and more HF bands to use, allow us to use equipment outside of the disaster zone (just like a satellite phone user). There are 566 repeaters in my home state of AZ, so the odds of another ham radio repeater still being within range (and unaffected by the disaster) is quite high. Your states repeater numbers are probably similar – look them up yourself and compare.

Second, newer 2nd generation satellite phones use low earth orbiting repeaters approximately 800 miles up, well above any natural disaster. What’s kept the public from using them more frequently (until now) was cost, but that’s no longer a factor, as satellite service is available for just $65.00 a month from us (that works out to just $2.17 a day with a free sat phone).

Many of the ham repeaters also have one or more backup power sources available, and thousands of them support IRLP or EchoLink modes, allowing those same small HT radios to “link” one repeater to another – around the world if needed.

Imagine being able to contact your family (living in another state) to tell them you’re ok just minutes after a disaster strikes – when the phone lines are down and the Red Cross hasn’t even arrived yet (or when you’ve fallen and broken your leg miles away from your vehicle and unable to reach a cell-phone tower). Hams (and satellite phone users) enjoy the security of knowing they can get a message through in virtually any situation (without depending on a fragile wired or cellular infrastructure that can easily fail or be overloaded when a disaster strikes).

Hopefully you’re now convinced that a small ham radio will provide much more range (with repeaters) than anything else of similar size, cost, or weight – short of a satellite phone (which we also offer). Let’s also explain the various radio(s) you might already have (or are considering) and what their true capabilities are (vs. the marketing hype).

FRS/GMRS, Marine, and MURS radios generally provide approximately 1 mile of communication range for every 1 watt of power, sometimes much less (depending on several factors including height of the antenna, surrounding buildings, mountains, etc.).

FRS (or Family Radio Service) units are all 1/2 watt radios with non-removable antennas that will normally provide a range of approximately 1/2 mile. FRS/GMRS combo radios usually have all 14 FRS UHF channels plus 8 more GMRS UHF channels, but these combo radios still have the non-removable factory antenna, plus their power levels are automatically set within the radio (1/2 watt on all 14 FRS channels, and normally up to 5 watts on only the 8 GMRS channels). Real world FRS/GMRS communication range is much less than the “Up to 50 Mile Range” marketing hype shown on the box.

Marine band handheld radios generally have 16 VHF channels (but can have as many as 88). Most have non-removable antennas, which help keep some of the handheld radios waterproof. Most radios have 1 or 2 watts output, but some claim up to 5 watts.

MURS radios (Multi-Use Radio Service) was previously a VHF business band service that required a paid license (like GMRS), but several years ago the FCC eliminated the license. Some MURS handheld radios can have up to 5 watts of power, but most have 2 watts. MURS units can have removable antennas, which will allow better performance than their FRS, GMRS, or Marine radio counterparts, but MURS radios tend to cost more.

CB radio communications have several unique issues to overcome in our disaster example. First, it’s highly unlikely that an outdoor CB antenna would have survived (if all other public service, GMRS, and ham radio fixed installations didn’t). That leaves mobile CB’s or handheld CB radios, but that still doesn’t overcome the biggest issue with using CB for emergency communications – which is physics.

CB radio (within the U.S.) is located between 26.965 and 27.405 MHz. That’s lower in frequency than Marine or MURS bands (approximately 152 MHz) or FRS/GMRS bands (approximately 462 MHz). Being on an HF band allows the CB signal to “skip” great distances (depending on the current condition of the various layers of the earth’s ionosphere, which will cause the HF radio wave to reflect). That skip effect, however, can cause EMCOMM problems.

Unlike hams (that have multiple HF bands, each with a different angle of radio wave reflection – thus allowing hams to “target” a range area that we wish to communicate with), CB users are stuck with whatever band conditions are currently present. So a CB signal from Phoenix may be heard in Pittsburgh, but a few minutes later might now be heard in Miami. That makes for some interesting CB conversations, but it means using CB radio for EMCOMM is highly unreliable.

Some also have the belief that when the “skittles hits the fan” (SHTF), they will just grab any radio (including any ham or GMRS radio) and use it, since they believe no one will care at that point. While that “may” be correct in a truly end of the world event, anything short of that will mean those folks will be very surprised to learn it simply won’t be that easy.

Counting on using the local GMRS repeater has already been discussed (remember the local GMRS repeater has already been destroyed in our scenario). Amateur radio repeaters are monitored for non-licensed use (even during Hurricane Katrina, Hurricane Sandy, wildfires, floods, and earthquakes) and the control operators have different ways of restricting non-licensed use by various methods. Waiting until the SHTF is NOT the time to discover you can’t access the repeater that you had counted on for your emergency communication requirements.

The Technician Class amateur radio (or ham) license isn’t difficult to obtain. (We offer two different methods of study, one is a $10 book and the other is a $25 internet based online training course that will provide you with all the information you’ll need and guarantees you’ll pass.) Your actual FCC test consists of just 35 questions. Pass the test and join the 730,000 plus hams already in the U.S.

I’m all for using any radio you have available in an emergency situation, but you simply can’t count on your home’s outdoor antenna(s) to have survived, nor should you count on any local infrastructure, which means you really have to count on the radio gear you can carry (and perhaps what’s in your vehicle). Most hams prepare a radio “go-bag” (or BOB) in advance, an idea I highly recommend. With the rapid cost reduction in satellite gear, more of them are also including a satellite phone with their preparedness equipment as well, or they simply use it as an everyday carry tool (especially if they own a business).

Since both amateur radio and satellite phone service provides so many more reliable emergency communication options it seems silly to depend on CB, FRS/GMRS, Marine, or MURS radios during an emergency (options that provide you with the least amount of range – when you need it the most). With today’s low cost two-way ham radios and satellite phones, combined with the ease of getting your license, two-way ham radio communication is really a great EMCOMM choice, but many business owners also write off the monthly $65 satellite service plan cost as a legitimate business expense. Whichever you choose, don’t pack your bug out bag without one.

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Like millions of other preppers, I live in the southwest portion of the United States. That affords me the advantage of great scenery, mountaintop views and vast areas of land

I remember cruising around some of the blogs I frequent last year I believe and ran into one YouTube channel from a guy who said he refused to get his HAM license for anything. I can’t swear by it, but I think I remember who he was, but that isn’t important. In this video he proceeded to show how you could look up any Ham radio license holders address from several different websites. He did this in response to someone who left very incendiary comments on his blog if memory serves and used this as a lesson in both OPSEC and how it’s bad for the government to have your name on any lists.

 

In another video this same guy went on to explain and demonstrate his own personal Ham Radio setup complete with a really nice antenna that was suspended from trees and hidden from view with additional comments about how he would not get his Ham license because he didn’t need to be on any government lists and if TSHTF, the first place they would go would be the Ham operators and take them offline.

This got me to thinking a while back and I really debated whether or not I should be like this guy and be a conscientious objector to the whole notion of licensing and just be a rebel with my antenna hanging in a tree. After a lot of thought and some research I decided to pull the trigger and get my Ham license and I want to explain why and discuss why you might want to do the same.

Isn’t Ham something yummy and delicious?

As context, let me explain what Ham is to those of you who aren’t familiar with the term. Ham Radio is also known as Amateur Radio and is a network of radio communications that rely on antennas and individual pieces of equipment to communicate using radio waves. Ham Radio has many strengths but chief among them for Preppers is its ability to be counted on in a disaster. Ham radio is perfect for grid down communications.

Ham Radio operators can still communicate if there is no electric power, satellites or cellular service. That is the primary reason they are the go-to method of communication for preppers as well as emergency response teams in virtually every large city. With the right equipment, Ham operators can talk to people in other countries using technology that was around in the early 1900s. If some disaster knocks out the cell phone service, emergency communications can be routed through Amateur Radio and you can keep in touch with others in your family, group, region or state pretty easily.

Ham radio is a valuable Prepper skill.

Ham or Amateur radios fall under the control of the FCC and there is a licensing process associated with being able to communicate on the radio. In order to speak on the air legally, you must first obtain your Technician level license and a call sign from the FCC. Your name and information will be listed in at least one public database and this information is freely accessible to anyone who wants to look.

Reasons Why You shouldn’t get a license

Like my friend above, I had some initial concerns regarding licensing because like any good Prepper, I am concerned with OPSEC. Even if I wasn’t into prepping, I wouldn’t want my name and address posted anywhere that someone could easily access it and part of communicating on Ham Radio is that you are required to give your call sign. Anyone you are talking to, or anyone simply listening in can look up your call sign and see where you are from. After learning all of this I started to weigh my options with Ham radio.

Like I mentioned above, Ham radio is probably the single best – disaster proof communication method the average person can use. As I began prepping my own family, the topic of communications came up several times. How would I communicate with my family in an emergency? How would we get news from others if for some reason there was a media blackout? The ubiquitous walkie-talkies that everyone has are effective at limited ranges, but what about longer distances? Ham Radio addressed both of those concerns nicely.

The only problem was that darned license.

At this point I could do one of two things. I could either get my license and put my name and address out there for everyone to see or I could simply buy the radio equipment and use it illegally. The thought process for some people is that if TSHTF, nobody is going to care if you have a license so the latter option is one I considered just like the YouTube guy above.

How hard can it be?

Ham radio works when other traditional communication methods are offline.

It turns out that two things influenced my decision on whether or not to be a law abiding citizen. The first and most obvious was my address out there on the interwebs. To get around that, I simply purchased a PO Box in a nearby town and used that for my FCC information. This is perfectly legal and still protects my address somewhat. Could someone look up my name, and then cross reference me in the phone book? I guess so, but who are we talking about here? If you have a psychopath running around trying to find you, chances are there are much easier ways of getting to your house. If this is in a post-collapse scenario, I have bigger problems.

Now, does that mean I should let my guard down and talk about anything on the radio? Not at all. The airwaves are public and anyone can listen in. For that reason alone, you should take great care in choosing what you talk about or divulge when you are talking on the Ham bands.

The second and more important factor that influenced my decision was the learning curve that is associated with Ham Radio. Getting started is pretty simple and once I had a radio, I was listening in on channels fairly quickly, but there is so much you can do that is outside of dialing through some frequencies. To fully take advantage of Ham Radio, I would need to practice and you can’t do that illegally, well without risk that is. Technically you can get on the radio and start talking without a call sign or you could lie, but just because radio waves are invisible, that doesn’t mean you can’t be found. Hams make a game out of finding antennas and it’s called a fox hunt. If you are talking on the radio and

shouldn’t be, someone can report you, they will find you and the fines from the FCC are steep.

Baofeng makes a great, affordable radio for preppers.

On the Radio – Almost

So with all that said, I went and took the exam for my Technician level license and passed. Now, as soon as the Government opens back up, and the backlog clears I will have a call sign and my name will start appearing in those databases. I am looking forward to finally being able to talk on the radio, but more importantly learning about the different frequencies and antennas I can use to communicate to others should our normal method of communications go down. I think of this as a decent trade-off for being able to communicate legally over the radio and besides, it isn’t like my name isn’t in several databases already. I am in the database for prior military service, the firearm database, IRS database etc. etc. If they want to find me they already know where I am and just because I have a radio now, that won’t be much more motivation to come get me I don’t believe. We’ll see.

 

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I remember cruising around some of the blogs I frequent last year I believe and ran into one YouTube channel from a guy who said he refused to get his

 

Following World War II, the small shortwave frequency bands allotted to amateur radio operators became crowded, and this is still true today. “Ham” operators were forced to switch to “single side band” transmission, which occupies only half the space of the familiar “AM” transmissions used throughout the commercial shortwave bands. In emergencies, the best information available on the radio may be from amateur operators, many of whom maintain emergency equipment for disaster situations.

Many “shortwave sets” do not receive single side band, and I recommend that anyone serious about preparedness consider acquiring one that will receive single sideband signals. Single sideband – capable sets are a little more expensive – typically in the $100 to $200 range, but in a crisis, are likely to be very much worth the extra expense.

A set which is single sideband capable will have “SSB” in the specifications, and have a switch marked “SSB” as well. If those markings are absent, it is almost certain that set will not receive single side band signals.

TecSunSSBRadio

Single Side Band communications do not have to be complicated or overly expensive.

WHAT IS A “SINGLE SIDEBAND” SIGNAL?

Let’s start with the traditional AM or amplitude modulated signal, which is standard throughout the commercial shortwave bands.

An AM station transmits a single, strong, steady signal when it is SILENT. That is the “carrier” signal. The carrier is on the station’s assigned frequency, such as 7,490 kilo-Hertz (7.490 mega-Hertz.)

When voice or music is transmitted, that carrier remains constant, unchanged in any way. The voice or music produces two small “clouds” of mixed frequencies on either side of the carrier. These “clouds” of mixed frequencies are each about 3 kilo-Hertz wide for voice, and maybe 6-10 kilo-Hertz wide if music is playing.

You know how every cell in your body contains, in the DNA, the full blueprint for how your body is built? Well each of those two “clouds” of mixed frequency contains the FULL information needed to convey the voice or music. Both “clouds” of mixed frequencies are not actually needed just to convey the voice or music. Even more surprising, that strong carrier frequency isn’t needed either.

Those two “clouds” of mixed frequencies are called “sidebands,” and they are referred to as “upper sideband” (USB) or “lower sideband” (LSB.)

Amateur stations usually just transmit one of the sidebands,and no carrier, and this takes up the least space on the busy amateur bands.

TUNING SINGLE SIDEBAND SIGNALS

Single sideband (SSB) transmissions require a little fiddling at the SSB receiver to hear the incoming signal as normal speech. Doing this does not require a technical background, though it is like learning a new electronics gadget – it requires a little practice. To begin tuning an SSB radio, the SSB switch is moved to ON. There is a helper knob called “FINE” or “fine tuning” and it’s a good idea to center that small knob.

In a normal AM radio, for best reception, you tune the dial, or punch in the exact frequency on the keypad, so you are CENTERED on that station’s frequency. In SSB, you tune to the UPPER SIDE or the LOWER SIDE of the signal, instead.

Normally, you will not know which side to tune, upper or lower , but once you hear a garbled voice you want to “clarify,” you try tuning the radio to one side, or the other. You will hear somewhat garbled speech, and you use the FINE helper knob to clarify the voice. If that doesn’t work, you tune to the OPPOSITE side of that signal, and try clarifying with the FINE knob again. That’s what it takes to tune an SSB signal.

If the above procedures don’t work for you, it may be that instead of tuning to one SIDE of the garbled voice signal, you have tuned to the center. Experiment and you will soon be able to know how to tune to the sides of the signal. THE “STEP” SETTING Today’s shortwave receivers with keypad tuning, even if they have a tuning knob as well, MUST be set to the smallest tuning “step,” which is usually 1 kilo-Hertz.

Any larger tuning step size will prevent properly tuning a single sideband signal. The radio’s manual will tell you how to set the tuning step, and once set, there should be no need to change it. You will know if the step setting is too high because signals will disappear when you attempt to tune to one side or the other. Watch the frequency readout, and you will see how many kilohertz each movement of the knob or tuning arrow button changes the frequency.

PERIODS OF SILENCE IN A SINGLE SIDEBAND SIGNAL

One difference you will notice with a single sideband transmission is that during gaps in the speech, you will hear background noise, as if the station isn’t transmitting. That is normal with an SSB signal, and is not a problem with either the remote station or your radio. Because an SSB transmitter does not transmit a carrier when no words are being said, there is nothing being transmitted.

BONUS – YOU CAN HEAR MORSE CODE TOO
When your receiver’s SSB switch is on, your set can receive the many amateur radio Morse code stations as well. While this isn’t of interest to many, those who have learned code for some other purpose, say scouting or military service for example, will be able to receive Morse stations with the SSB switch on.

WHAT FREQUENCIES TO LISTEN TO FOR AMATEUR SSB SIGNALS

1800 – 2000 kHz (1.8 – 2.0 MHz) … 160 meter band
3750 – 4000 kHz (3.75 – 4.0 MHz) … 75 meter phone
7150 – 7300 kHz (7.15 – 7.3 MHz) … 40 meter phone
14150-14350 kHz (14.15 – 14350 MHz) … 20 meter phone
18110-18168 kHz (18.11 – 18.168 MHz) … 17 meter phone
21200-21450 kHz (21.2 – 21.45 MHz) … 15 meter phone
24930-24990 kHz (24.93 – 24.99 MHz) … 12 meter phone
28300-29700 kHz (28.3 – 29.7 MHz) … 10 meter phone
26,965 – 27,405 kHz (26.965 – 27.405 MHz) … “CB” radio

“CB” operators will sometimes use AM, and sometimes SSB. Valuable emergency information can be obtained from CB operators too.

AM SIGNALS CAN BE HEARD WHEN THE SSB SWITCH IS ON
If you come across an AM station when the SSB switch is on, you will hear atone mixed with the voice. Switch SSB off for listening to that particular AM station.

EMERGENCY POWER
Unfortunately, at time of writing, manufacturers tend to provide no solar charging or hand crank generator features with their SSB-capable radios. This makes powering the radio when the AC power is down more complicated, but SSB-capable radios are in the price range where an EXTERNAL POWER JACK is available. There are so many variations of emergency power sources that I can’t give an exhaustive list of options here. But I can give a couple of general rules:

POLARITY is CRITICAL. There is no way to know if a given radio is protected for accidentally applying the wrong polarity to the external power jack, so you must be absolutely sure what the polarity at your external power cable plug is before connecting to the radio. An inexpensive hardware store voltmeter is a good investment for preppers, and can show polarity. You don’t want to destroy your radio inadvertently. See the polarity test illustration on the following page.

MultiMeterTesting

Testing the polarity on your batteries.

IMPORTANT: See also the TIPS FOR USING METERS in Appendix A below.

VOLTAGE is CRITICAL. Just as with polarity, you must not feed your radio external power which can damage or destroy it. A radio may be able to tolerate, say, 15% over-voltage, but even there, you may shorten its life. The good news is many radios will still operate at as little as 60% of normal voltage. This means that a USB (5-volt) power source can power a 6-volt radio.

(I use “Enersys” 2-volt sealed lead-acid cells to make up the voltage I need for my radios. Using 2-volt cells allows me to make up any voltage needed for equipment which uses a variety of voltages. See diagram below.)

BatteryBackUp

Back up power supply.

SOLAR or HAND-CRANK CHARGER output voltages can be much higher than the batteries they are charging, but are still safe WITH BATTERIES . But solar charger and hand-crank charger voltages VARY, A LOT, and these should NOT be fed directly into the radio’s external power port. This is because their energy output is small and won’t harm batteries, but their widely varying voltages can potentially damage sensitive solid-state radio components.REGULATORS ARE REQUIRED WITH SOLAR OR GENERATOR SOURCES

Whenever the solar cells or hand-crank generator are in contact with radio circuitry. In a radio with a crank, the hand-crank generator is connected to the batteries inside. However, there is an important detail – a built-in hand crank generator or solar panel has a built-in REGULATOR so it cannot harm the radio. An EXTERNAL hand crank generator or solar panel, unless specified by the manufacturer as having regulated output, must be assumed to NOT have regulated output. What this means is, use external hand crank generators or solar panels without certified regulated output ONLY for charging batteries removed from the radio.

Note that standalone hand-crank generators are commercially available. USB SOLAR and HAND-CRANK CHARGERS (5 volts) have literally taken over the emergency power marketplace for small equipment. This means that when shopping for emergency radio power, special attention must be paid to the VOLTAGE RATINGS of a charger you are considering. USB power is always 5 volts. This will work fine with a radio rated at 5 or6 volts, but may not work well, if at all, with a 9- volt radio. It is probably OK for a 4.5 volt radio. USB CHARGERS may or may not charge a 6-volt battery set.

KTOR

Hand crank generators will give you an alternate way to recharge batteries.

USB’s 5 volts is too high for a 3 volt radio, and there are some scanners which operate on 3 volts. USB’s 5 volts is too low to run a 12-volt radio, or charge its batteries. You can see that a non-technical person is probably going to need experienced technical help with the matter of external power supplies for radios.

GETTING HELP

With both the SSB tuning issue, and putting together a safe and effective emergency power setup, I recommend contacting a local amateur radio club. If there is none, amateur radio operators will often have unique antennas set up at their homes. Local shops which handle electronic parts in particular (e.g. Radio Shack) are also likely to know some of the local ham operators. Many ham operators are glad to help with matters related to their hobby

APPENDIX “A” – TIPS FOR BUYING AND USING METERS

This appendix may be a little dense for readers who just want to tune their radios to an SSB station. However, readers who are interested in external emergency power for radios and other equipment will need to have some familiarity with meters.

Meters would include “multimeter” (usually volts, amps/milliamps, and ohms), and battery testers. Both are very important for emergency preparedness and many are not outrageously expensive. Here are my recommendations for buying and using them:

  1. Having more than one of each type of meter is very wise. Meters can fail just as any other equipment, and there are really no substitute products for meters. I recommend purchasing two lower priced models in place of one high-priced model.
  2. Both analog (moving needle) and digital (numeric window) meters will do the job. Analog meters are more sensitive to rough handling or dropping. Try to avoid static electricity when using a digital meter. Frequently touching something that is grounded to discharge your body is one way to do that.
  3. Meters can sometimes be repaired, but in an emergency situation, it’s best to assume meters will not be repairable , other than perhaps repairing broken test leads.
  4. Having both multimeter and battery checkers on hand is highly recommended.
  5. Unless you have a fairly good background in electricity/electronics, I recommend NOT using either the current (amp/milliamp) or resistance (ohm) or “diode” scales. Applying voltage to those scales will at least result in a blown fuse if you’re lucky, or maybe a totally ruined meter. (This causes lots of tears!)
  6. Most multimeter have both AC and DC voltage scales. Take your time and be sure which type of voltage you are about to measure. (If you meter is set for DC voltage, it will give a false reading of zero with an AC voltage source.)
  7. If you have any doubt whatsoever about the maximum voltage level you are about to measure, start the meter on the highest voltage scale, and reduce the scale setting in steps until you get an understandable voltage reading. Meter movements (analog) or digital circuitry can be destroyed by applying more voltage than the scale is set for. Very important for battery checkers when measuring any batteries other than simple single cells. (Such as lantern batteries,and other multi-cell batteries. Also be very careful to set the 9-volt scale for “transistor” batteries which are small but contain multiple cells!)
  8. Some multimeter may be “auto-ranging,” meaning they will select their own scale. If your meter appears to be an auto-ranging unit, read the manual about what the maximum voltage limits are for that particular meter.
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  Following World War II, the small shortwave frequency bands allotted to amateur radio operators became crowded, and this is still true today. “Ham” operators were forced to switch to “single