If the things above are not true, what is "The Real Deal"?
First off let me say I have been around cb radios for years but do not
claim to be a "technician". You don't need a proclaimed "technician" to
figure this one out. Secondly let me say the most important factors in
your radio are it's design, construction and alignment. A good radio
with 1 watt will outperform a 5 watt radio with poor design,
construction and alignment. It's all about stability. Have you ever
noticed when you hear someone with a "peaked out" cb radio whistle in to
their mic you hear strange distortions in their signal. It's almost
like you hear other whistles of different audio frequencies at the same
time. Those are harmonics. Have you ever noticed when people get their
cb radios "modded out" they sound pinched off like they have a clothes
pin on their nose. They seem louder but the deep part of their voice is
now gone. That is a loss of audio bandwidth. A sacrifice that appears
louder, but it's not. You see the human ear is more sensitive to a
higher pitch in the vocals. You will usually hear a person scream
farther than a cow mooing at the same faint volume levels.
Cb Audio Bandwidth Example: Think
of the transmit audio of your cb like you would tune a car stereo
equalizer. You have Bass, Mids and highs. What happens when you take the
bass completely out? It seems a bit louder but less dynamic. Now what
would happen if you compressed all the audio into the center slider on
the EQ. All EQ level sliders down but the 1 or 2Khz. How would that
sound. Screechy loud, tinny and nearly distorted. This is what some
people are getting when they get their radio improperly "peaked out".
It's narrowing the frequency response of your transmit audio. It is of
no benefit to the performance of your cb radio operations. All you are
doing is tickling the higher frequencies of people's ears. "well it's so
loud it's on the verge of squealing, it must be loud". No. What does
that same signal sound like when they are 40 miles away at S1 signal on
the meter? It sounds like someone strangling a chicken. You need all the
dynamic range of the radio's audio you can get so people can understand
you in conditions where your signal is very weak. You need highs mids
and lows in there so people can distinguish your words.
Example 2: Quality
vs. Quantity. Example Scinereos. 1: You hear a Ham Radio Operator using
a $2000 HF radio on AM CB Radio, and then you have some peaked out
super modded galaxy with a 300 watt linear maxed to the hilt. The guy
with the CB is making a lot of noise but the Ham Radio seems to be
talking through him. Another example is, notice how some radios will
"talk over" other radios that are giving a higher signal reading. Why is
that? Did you ever notice that someone with an untouched cb radio has
less heterodyne when talking at the same time as other cbers. Another
words, when cbers on AM talk at the same time a squeal is produced. Have
you noticed, if you get two untouched "barefoot radios" talking at the
same time, you can often understand them both instead of all the
excessive squealing noises? (heterodyne)
Here is another example that will help put this all in perspective.
Have you ever heard one of these people with a "super peaked out radio"
with their mic turned all the way up get on SSB? They sound horrible.
They sound tinny, screechy and like they have a clothes pin on their
nose. Distorted and scratchy. This may come as a shock but cb radio
operators are known for horrible audio.
What is too Loud? Have
you noticed what happens when you turn up your stereo too loud? It does
not get any louder, it just starts to buzz and distort. If you were
looking at this signal on a scope you would see nice sharp peaks start
to level off at the top at a constant. This is called "flat topping".
Something can only get so loud before it levels off and goes flat. With a
cb radio, what usually happens is that pinched off clothes pin on the
nose sound. People can still kind of understand what you are saying,
but, it's far from a positive listening experience. If your audio is
pleasing to the ear, people will want to contact you.
RFI/TVI:
As stated above. Something can only get so loud before it "flat tops".
"But it said it's putting more power out on my cb watt meter". Sure it
is, but that perceived "power" is not helping you talk further. It's
going in your neighbor's phone and TV. Notice how the guy with the stock
radio makes all the same contacts as you or more, but they are not
getting in to their neighbor's electronics. It's not because you are
louder, it's because your transmission has gone unstable. The more
unstable the more harmonics. Not only are you producing unwanted
harmonics in your transmit audio, but you are also putting out harmonics
by way of radio signals.
Get this.
Sometimes you will have ham operators complain of cbers talking on the
CW portion of 10 meters in the area of 28.000-28.085 Mhz. You have
truckers talking there yes, BUT, a lot of the time these people are
hearing a harmonic of cb radio channels. They hear this and think "I
hear cbers talking on ham radio frequencies". This is not always true.
The next time you hear a trucker pass through running 300 watts on a
"super peaked out radio" jump up above twenty eight hundred and have a
listen. You may hear him clear as day but with considerably less signal.
Harmonics. Notice how you don't hear stock FCC Approved cb radios up
there producing harmonics. If they did, they would not be on the market.
So you have all of these Ham Operators running around chasing harmonics
thinking these people are on Ham Frequencies. Once again, some of them
are. It's best to tune to the cb band after hearing it to see if what
you are hearing is a harmonic. Tune down to cb, if you hear the same
voice with greater signal, there you have it.
So how do I get "broadcast audio" on a cb radio that sounds like a proper radio station.
Easy answer. Don't pay to get your radio tweaked out, rather pay
someone with proper knowledge and experience to "Align the Radio". Some
radios are out of tolerance and alignment from the factory. The thing
needs to be aligned after it's been switched on for some time and
allowed to come up to operating temp. If you have someone align your
radio (especially a SSB radio) cold on the bench, when you get home and
let in run two hours the frequency will be a bit out of whack, being the
clarifier is receive tuning only. The radio needs to be work horsed on
the dummy load to get it up to temp and then aligned. Cb Radios are
pretty sensitive to temperatures on SSB. They naturally drift a little,
but, they will drift less if the radio is up to operating temp and
aligned properly. Not "Peaked Out", "Tweaked Out" or "Super Modded". Alignment.
Modulation: As
you learned above, your "modulation" (AM CB Radio Term) should be set
on a scope with your voice. Have you ever heard those people with a deep
voice get on a "tweaked out" radio? They sound like they are talking
through their nose via some vibrating wax paper and a paper tube Those
low mid tones in their voice are "flat topping" that portion of the
audio bandwidth. When this happens the nasty tones override the entire
range of the voice. Often turning their mic down will not help as the
audio bandwidth is "pinched off" due to a poor "peak and tweak" or
misalignment.
Here's another example
of poor cb radio audio. Everyone has heard these fly by night cb radio
dj's that hold a mic up to a speaker and play music on the air. What do
you usually hear? You hear something that sounds like a 50 gallon drum
half filled with nuts and bolts rolling down the street. You hear mostly
all the tinny high sounds. The more their radio is "tweaked out" the
worse it sounds. Now as we learned in the car EQ example above, does it
get any louder when you cut all EQ levels and turn the middle one all
the way up? No. Anything after "as loud as it gets" is distortion.
How does livecbradio.com do it? Livecbradio.com
uses a bone stock Cobra 148 GTL. The "Broadcast Audio" is superb.
People have said "that thing sounds like a FM radio station". The
Livecbradio.com mic audio on SSB has also been claimed to "sounds like
AM". Now don't get me wrong, it does not sound like Amateur Radio
Wide-Band SSB, but, it sounds Amateur Shortwave Radio Station Quality.
Number one, the key is the radio is not "peaked out". Number two the
livecbradio.com TX audio goes through an 11 band EQ and other
processing.
Let's say for example we have 300hz-2000hz audio bandwidth to work
with. It's not much compared to a hifi or commercial "radio station",
but it's enough to sound really good. We have also had reports like
"your audio is loud and clear". Is it loud? No, as described it can only
get so loud before distortion. It sounds "loud" because you are hearing
all frequencies in a dynamic separate fashion in harmony, instead of
everything all run together and buzzing. Loudness is mainly an illusion
to the ear. You may not hear the bass guitar like you do a regular
guitar in a rock and roll band, but, when you remove the bass guitar you
can sure tell it is missing. Point being, when you get your radio
"peaked out" you are removing some range of audio frequency..
I am not suggesting
everyone go out and attach an EQ to the mic line of their cb. What I am
suggesting is proper alignment of the radio combined with the right
microphone for your voice. For example stock microphones can get a
little bassy for someone with a deeper voice. Something like a properly
adjusted D104 (crystal microphone) will restore some of the highs in
your voice for better sound quality. Now someone with a higher pitched
voice can sound too tinny and scratchy on a D104 crystal cartridge
microphone. This person might want to select a "Amplified Condenser"
style of microphone to restore some of the bass in their voice. The
stock microphone that came with the radio is often the best selection
for someone with a medium to high pitched voice. The stock microphone is
almost always a "non amplified condenser" style.
"But Earl's Cb Shop said I can talk further if I get my radio peaked out". I
suppose this would be true if they could turn up your output power
without sacrifice to your audio bandwidth. This is most often not the
case. The Livecbradio.com bone stock Cobra 148 GTL has talked 50 miles
locally. How? Because they can understand the people talking when the
signal is very low. They still hear all the range of the voice. If the
radio is "peaked out" to the hilt and the audio bandwidth is pinched
off, like that EQ with one slider all the way up and the rest down, what
are they going to hear? They will hear some amplified scratching noises
with what sounds like someone talking through their nose. You are only
making power within that range of your voice while the other tones of
your voice seem to be gated out, like the removal of the bass guitar
example above. Not good. Now it is true that a more tinny and narrow
audio signal is usually understood easier at extremely low signal
strengths, but, in cb radio it's often overkill and working against you.
Number one your job as talker on the cb radio is to make sure your
voice is intelligible and people can clearly understand you in all
conditions.
What happens when you
have really good audio and a transmitter that is in proper alignment?
You can talk through and around other stations talking at the same time.
Say you have 2 rock bands playing at the same time. They are both
playing the same song and both have equal volume levels by whole. The
only difference is, one of the band's audio is coming through an
oversize toilet paper tube. Without thinking in terms of directional
ability of sound, who is going to be heard more clearly? Come to mention
it, "talking through a tube" is often another common bad cb radio audio
report.
I am not trying to put
every cb radio tune up shop out of business. I am merely pointing out
the standard of cb radio audio can easily be raised with a little common
sense. Cbers need to consider adjusting their transmit / microphone
audio like they do the EQ on their car stereo, as opposed to firing up a
loud bull horn in a hostage standoff. No I am not some HiFi SSB Amateur
Radio fanatic. I have heard wide band audio on a wide band capable
receiver that is over the top. Your own personal balance is there
waiting for you. The problem is, the people with the most horrible audio
on cb radio will probably not have read this far down the page. But, we
can all pull together to help raise the standard. The simple car stereo
eq analogy can go a long way to these people with their D104's cranked
up all the way with a "peaked out radio". Cb gear has always been about
influence. When a newbie hears billy bob 718 on a distorted bullhorn
with echo, they think this must be the standard. What cb needs is a
little more influence to help the stragglers along.
Talk Back:
"Talk back" is not your "broadcast audio". What you sound like coming
out of a "talk back" speaker has little or nothing to do with how you
sound to others. You need to get another receiver / cb to monitor your
audio. Listen with the antenna unplugged on the extra receiving unit.
Turn things down so your S's sound like ssssss instead of
KIRCHSSKWSHSSS!
What would be some great setups for good cb radio transmit audio?
Number one, if I was serious about my transmit audio on cb I would get
a "W2IHY" microphone eq. If I could not afford that I would simply put a
Home Stereo EQ in line on the mic line of my cb via simple attenuate
interface. i.e. 2 resistors. Or I would use a computer soundcard to do
my audio processing. In most cases this would probably take an
additional DPDT relay or switching to handle this. Since a normal cb mic
needs DPDT switching this would be mandatory. i.e. DPDT pinball button
or DPDT vox/ptt switching relay. The same can be done for rack gear. In
effect all you are doing is making an "effects loop" on the audio and
shield wires on the microphone. Two wires going from mic get cut and run
to device. The output of that device then goes back in the mic and down
to the radio where it was cut. Resistors are then placed in certain
areas on the mic line in series and parallel combination(s) to reduce
voltages when needed. Example: Speaker output of a sound card going in
to mic line is too much voltage. Put 2 simple resistors in line as
described for "attenuation of signal". You can find all the diagrams for
these things by googling "echolink interface" and "radio to soundcard interface"
and things like that. A simple "isolation transformer" is also a good
addition to your interface to protect against "ground loops".
If i just wanted a
good mic I would get something that matches my voice as described above.
To be quite honest I would find something with a powered "electret
cartridge". An example of an electret mic is a simple cheap computer
mic. They make cb mics with electret cartridges.Examples of electret Ham
Radio mics that would work would be the Kenwood MC60 or Icom SM20
desktop mics. Notice how "chat room audio" with people using electret
mics is so clean and dynamic. Good bass and good high end without being
tinny. An "echomax 2000" has an Electret head, but unfortunately for
this style they don't sound all that great on some radios.
You have tons of
options to sound great! If you are serious about being on a radio it
just makes good sense to do a little work to make sure you sound good. A
good rule of thumb would be ignore what is popular and what people are
saying. One doesn't have to spend thousands on rack gear to tinker with
this kind of stuff. People have been known to sound great running their
mic audio through an old realistic voice box they obtained at a garage
sale.
If I wanted a sure fire out of the box perfect setup without the fuss I would say "Get a new untouched Cobra 148 with an Astatic D104
m6b handheld microphone. Job Done. If your voice is higher in pitch
than most, skip the D104 Handheld Mic and look for an amplified
condenser mic. If you speak with a wispy tone and a lot of breathing the
stock mic may be your best bet.
HIFI ESSB & HIFI AM Bandwidth on CB Radio? Yes
they are out there. There are at least half a dozen extended SSB
operators on the conventional sideband cb channels. On channel 6 you
have a few wide band AM operators as well. You know, the people that
sound like a dj on FM Radio with that heavy bass. The sound of these
radios is nothing less than impressive.
Here is some more low
buck inspiration. I heard a guy on an old radio shack ssb base station
that had a home stereo EQ wired in his mic line. It sounded like a $2000
Ham Radio with the stock microphone. It sounded nice and flat with a
nice fat low end with good highs. On SSB you get a little of that low
latency attack time with your words using an eq. Your words become very
distinctly precise and separated instead of run together. Tight. A $15
Cb Radio on SSB with an EQ on the Mic line sounds better than a new
$1500 HF Ham Radio using it's own stock hand mic. Sounds like a far
fetched claim but it's true.
OK, here is a touchy subject, MIC DISTANCE.
A great percentage of people on the cb sound horrible because of the
distance they speak from their microphone. Someone that gets too close
to an electret mic (like a computer mic) will make it "PoP". Like a
helicopter pilot. People on condenser mics that get too close sound like
they are too bassy and muffled. The people that get too close to an
amplified crystal mic like the D104 are the worst. You can hear the spit
in the side of their lip and every breath and weez they make. These are
the people that refuse to turn their mic down no matter how many people
tell them. They think in their mind "Oh they want to trick me in to
turning down my power". This is why we cbers call it "Modulation".
Otherwise known as power to cbers. To turn down your D104 would be a
fate worst than death. hi hi. Know how you sound. Another tip, don't
speak louder or get closer to the mic when signal conditions change.
Getting up on the mic and yelling is not going to increase your ability
to maintain weak signal communications.
A word about Linear Amplifiers on cb radio.
I have spoken base to mobile 50 miles with 4 watts on a stock radio
with EQ. On AM. I have talked all over Europe from Nebraska on SSB using
2-12 watts. (last sunspot cycle) I spoke to Australia, Saudi Arabia,
Japan and Africa with 12 watts or less on CB Radio SSB. In
experimentation I have made overseas contacts on 1 watt with a simple
Antron 99 antenna. My point. Cbers need to worry a little bit more about
radio procedures and conduct to prepare for the coming tide of DX. Like
last time around the DX will come wash all local cb communications away
for years. You won't be able to talk to your neighbor down the street
by cb. At times it will get so intense it will even wash out all
stateside DX on AM with exception to channel 6 AM. It will be "30db of
hash and trash" day and night for years. Only truckers within eye shot
will be able to communicate via cb radio. The only real survivors in
this will be those on SSB and those with 1000+ watt amps to run on AM.
It's going to get nasty. Cbers need to prepare for this or it's just
going to come as a huge shock. Buying a big amp to put on your big stick
will not help you. Your best bet would be a directional antenna and
some decent audio combined with a knowledge of proper radio conduct.
People are going to find that an over powered cb that is too loud
screaming, "this is billy bob ba lam a lam a ding dong cmon in" is not
going to cut it. That sort of activity will just be a small percentage
adding to a huge noise floor on the band. No, the point is not to turn
CB Radio into Ham Radio. The point is you better be prepared. Your local
cb cliques are going down. The days of sitting on channel 19 agitating
the truckers will be over for years. That's right, a huge tide is coming
to wash all the trash off the cb radio. Only the true die hard cb radio
hobbyists and short wave listeners (SWL's) will remain. It will be
interesting listening that is for sure. Those cbers not around last
cycle have a rude awakening coming. The livecbradio voip program will
always be open to communicate with like minded radio people looking for
conversation.
73
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