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Its Me Its Me is offline
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First recorded activity by BoatBanter: Jan 2016
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Default VHF vs CB Antenna?

On Wednesday, November 28, 2018 at 2:18:19 PM UTC-5, Mr. Luddite wrote:
On 11/28/2018 1:47 PM, wrote:
On Wed, 28 Nov 2018 07:17:33 -0500, "Mr. Luddite"
wrote:

On 11/28/2018 7:04 AM, Keyser Soze wrote:
On 11/28/18 7:02 AM, Mr. Luddite wrote:
On 11/27/2018 11:15 PM,
wrote:
On Wed, 28 Nov 2018 03:06:28 -0000 (UTC), Bill
wrote:

Mr. Luddite wrote:
On 11/27/2018 7:36 PM,
wrote:
On Tue, 27 Nov 2018 17:47:44 -0500, "Mr. Luddite"
wrote:

On 11/27/2018 5:22 PM,
wrote:

I have a uniden CB radio (new) and have an existing larsen wb vhf
radio already on my truck. Will this antenna work with my new
radio.
Derek


Can't determine without knowing what freq range the truck antenna is
"cut" for.Â* There are two VHF bands, low-band VHF (49-108 MHz),
high-band VHF (169-216 MHz).Â* Marine radios operate in the high
band.

Generally it will receive ok but transmit range may be limited
due to
high standing wave ratio (SWR).

Even a marine VHF antenna should be tweaked in terms of length to
minimize SWR in the middle of the radio's freq range.


He is talking about CB (27mz) so that is over twice the wavelength of
the lowest frequency VHF.
SWR is really going to be ugly but since they are capped at 5w,
(usually more like 4.5) I doubt the magic smoke comes out but he
won't
be "getting out" far either.

If his "truck" is a real one (breaker good buddy size) and he has
8-9'
from mirror to mirror the best antenna is the co phasers you see on
big rigs. Otherwise it is hard to beat a bottom coil loaded ~48"
antenna right in the center of the roof.Â* That is what I had on my
van
but you had to remember to take off the vertical when you went into a
parking garage. ;-)



I completely missed that it was a CB radio he was talking about.
Thought he was talking about a new VHF Marine radio.Â*Â* But the antenna
issues remain the same. For max range whatever antenna he uses
needs to
be of the proper length.Â* At 27 MHz a full wavelength is about 103
inches.Â* A half wave antenna would be about 51.5 inches long and
aquarter wave length antenna would therefore be about 25.75
inches.

If really anal about these things, an SWR meter should then used to
trim
the antenna length to the lowest SWR on channel 20 (mid-range).

I have an old SWR meter from the CB craze years that I never use
anymore
but for some reason it's one of those things I just can't throw away.






I have one for my marine VHF.Â* Have not used it in years.Â* Actually
I am
looking at a new radio for the boat.Â* One with AIS.Â* Maybe Santa
Clause.

My wife has her phone. That is all we needÂ* ;-)
Worst case I call a tow pirate but I have plenty of neighbors who owe
me a tow.
Sinking is not an issue, we will just wade ashore, I will plot a
course through the mangroves with my aerial photos and boy scout
compass and we will walk home.
I do have loppers on the boatÂ* ;-)


Back in the CB craze (late 70's)Â* Radio Shack sold a base unit that
could easily be modified if you knew what you were doing.Â* I bought
one along and acquired a list of the required modifications.

The modifications added an additional 40 channels (unauthorized) and
increased the carrier power from 5 watts to 15 watts.
It also increased the effective single sideband mode power to
over 30 watts depending on how much you modulated it which was
also another "tweak".Â*Â* At the time we lived in a rented house
near the shore and on Sunday mornings I could communicate via "skip"
with people in much of eastern Europe, as far away as Italy.Â*Â* In the
evening I could easily talk to people west of the Mississippi using
skip as far away as California, depending on the time as the sun set..

Ended up doing the same mods for a couple of people who also
bought the same Radio Shack radio.

Don't know whatever happened to that radio.Â* I lost interest in CB
after a while.


Never understood the "CB culture." I don't even like to talk on the
phone that much.


For a while CB had two cultures, the "good buddy" road travel
communications and people like me who were more interested in
seeing how far you could communicate with others, similar to
HAM radio and their custom of exchanging "QSL" cards by mail confirming
successful contacts.

Only time I was glad to have a CB radio in my vehicle was before
cell phones came along. Was traveling up Rt. 95 from Long Island
heading home at about one in the morning. It was raining hard
and a car whizzed by me in the fast lane. Suddenly, all I saw
were his headlights flashing back at me several times. As I
approached him, his car was upside down on the side of the road.
He had hit a large puddle of water and had hydroplaned, causing
his car to hit the center guardrail and then flip several times.

Got on the CB and after a few tries contacted someone who called
the state police. I helped get the guy out of his car and he
sat with me in mine until the police arrived. He was shaken up
big time but didn't appear to have any serious injuries.



===

These days everyone has emergency communications via cell phone. It's
much more reliable and easy to use. Ham radio is also experiencing a
decline in popularity as the internet and sat phones have made it easy
to communicate all over the world.


That's too bad because it wasn't really all about continuous and
reliable communications. The challenge was in frequency selection,
antenna placement, etc. just to see how far you could establish
communications. Kinda a nerdy hobby I guess.

Even in the Navy on one of the ships I was assigned to and before it's
homeport was changed from Newport, RI to Naples, Italy we used to
try to maintain comms with another ship using the least amount of
transmitter power as possible. Best we did was a two-way FSK teletype
connection off the coast of RI to another ship transiting through
the Straights of Gibraltar using less than 1,000 watts.


I'm not a ham but I know a couple. There's a challenge some of them participate in to see who can get a QSL card from 100 countries using only 1 watt.. One of the guys had cards from 60-70. The atmospheric conditions have to be just right to form a transmission line from you to that country. They call it "skip".

Ham operators are still pretty useful in certain situations, especially when the cellular system is down. Fo example, there's a privately owned (by ham clubs) radio network that covers the Carolina's, and up into Virginia and part of Georgia. With a ham license and a $400 handheld, you can talk to another ham anywhere in that area. That's not an unusual thing.