<div dir="ltr">Existem umas fotos, mas que agora não encontro, de antigos "carochas" da Brigada de Transito que usavam, penso que nos anos 50 e inicio dos 60 do século passado a banda dos 27 MHz com antenas verticais com perto de 2m de comprimento. Os rádios eram moveis a vavulas,<div><div><br></div><div>João Costa (CT1FBF)</div></div></div><div class="gmail_extra"><br><div class="gmail_quote">2016-01-28 11:28 GMT+00:00 CT5GOQ <span dir="ltr"><<a href="mailto:ct5goq.rui@sapo.pt" target="_blank">ct5goq.rui@sapo.pt</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Bons dias caros colegas, <br>
<br>
Esses rádios de base me recordo de ver iguais no meu antigo serviço
Antena1 no Quelhas, muito velhinhos se diga de passagem.<br>
Mas hoje se vem a saber que eram do ano de 1948.<br>
<br>
Um Abraço<br>
CT5GOQ<br>
<div><br>
<br>
-------- Mensagem reencaminhada --------
<table border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<th align="RIGHT" nowrap valign="BASELINE">Assunto:
</th>
<td>ARLA/CLUSTER: Sabia que os primeiros Radios CB em 1948 a
vavulas, operavam na banda de 460 a 470 MHz.? Só em 1958
passaram para os 27 MHz.</td>
</tr>
<tr>
<th align="RIGHT" nowrap valign="BASELINE">Data: </th>
<td>Wed, 27 Jan 2016 11:25:44 +0000</td>
</tr>
<tr>
<th align="RIGHT" nowrap valign="BASELINE">De: </th>
<td>João Costa > CT1FBF <a href="mailto:ct1fbf@gmail.com" target="_blank"><ct1fbf@gmail.com></a></td>
</tr>
<tr>
<th align="RIGHT" nowrap valign="BASELINE">Responder-Para:
</th>
<td>Resumo Noticioso ARLA/CLUSTER
<a href="mailto:cluster@radio-amador.net" target="_blank"><cluster@radio-amador.net></a></td>
</tr>
<tr>
<th align="RIGHT" nowrap valign="BASELINE">Para: </th>
<td>Cluster-ARLA <a href="mailto:cluster@radio-amador.net" target="_blank"><cluster@radio-amador.net></a></td>
</tr>
</tbody>
</table>
<br>
<br>
<div dir="ltr">
<p style="margin:0.5em 0px;line-height:22.4px;color:rgb(37,37,37);font-family:sans-serif;font-size:14px">Â </p>
<table style="width:22em">
<tbody>
<tr>
<th style="text-align:center;font-size:125%" colspan="2"><br>
</th>
</tr>
<tr>
<td style="text-align:center" colspan="2"><a href="https://en.wikipedia.org/wiki/File:ALGROS2.JPG" target="_blank"><img alt="ALGROS2.JPG" src="https://upload.wikimedia.org/wikipedia/commons/thumb/5/51/ALGROS2.JPG/300px-ALGROS2.JPG" style="margin-right:0px" height="199" width="133"></a>Â <img src="cid:part3.06050107.07070300@sapo.pt" alt="Imagem
inline 2" style="margin-right:0px" height="101" width="130"></td>
</tr>
</tbody>
</table>
<p><span style="font-weight:bold;text-align:center">Alfred J.
Gross </span>(W8PAL) invented the CB radio in 1945</p>
<p>The citizens band radio service originated in the United
States as one of several personal radio services regulated by
the <a title="Federal Communications
Commission" href="https://en.wikipedia.org/wiki/Federal_Communications_Commission" target="_blank">Federal
Communications Commission</a> (FCC). These services began in
1945 to permit citizens a radio band for personal
communication (e.g., radio-controlled model airplanes and
family and business communications). In 1948, the original CB
radios were designed for operation on the 460–470Â
Megacycle UHF band.<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-2" target="_blank">[2]</a></sup>
There were two classes of CB radio: "A" and "B". Class B
radios had simpler technical requirements, and were limited to
a smaller frequency range. <a title="Alfred J. Gross" href="https://en.wikipedia.org/wiki/Alfred_J._Gross" target="_blank">Al
Gross</a> established the Citizens Radio Corporation during
the late 1940s to manufacture Class B handhelds for the
general public.<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-3" target="_blank">[3]</a></sup></p>
<p><a title="Ultra-high frequency" href="https://en.wikipedia.org/wiki/Ultra-high_frequency" target="_blank">Ultra-high
frequency</a> (UHF) radios, at the time, were neither
practical nor affordable for the average consumer. On
September 11, 1958<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-4" target="_blank">[4]</a></sup>
the Class D CB service was created on 27Â Megacycles, and this
band became what is popularly known today as "Citizens Band".
There were only 23 channels at the time; the first 22 were
taken from the former <a title="Amateur radio service" href="https://en.wikipedia.org/wiki/Amateur_radio_service" target="_blank">amateur
radio service</a> 11-meter band, and channel 23 was shared
with radio-controlled devices. Some hobbyists continue to use
the designation "11 meters" to refer to the Citizens Band and
adjoining frequencies. <a title="Part
95 (page does not exist)" href="https://en.wikipedia.org/w/index.php?title=Part_95&action=edit&redlink=1" target="_blank">Part
95</a> of the Code of Federal Regulations regulates the
Class D CB service, on the 27Â MHz band, since the 1970s and
continuing today.<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-5" target="_blank">[5]</a></sup>
Most of the 460–470 MHz band was reassigned for business
and public-safety use; Class A CB is the forerunner of the <a title="General Mobile Radio Service" href="https://en.wikipedia.org/wiki/General_Mobile_Radio_Service" target="_blank">General
Mobile Radio Service</a> (GMRS). Class B CB is a more
distant ancestor of the <a title="Family Radio Service" href="https://en.wikipedia.org/wiki/Family_Radio_Service" target="_blank">Family
Radio Service</a>. The <a title="Multi-Use Radio Service" href="https://en.wikipedia.org/wiki/Multi-Use_Radio_Service" target="_blank">Multi-Use
Radio Service</a> is another two-way radio service in the <a title="Band III" href="https://en.wikipedia.org/wiki/Band_III" target="_blank">VHF high band</a>.
An unsuccessful petition was filed in 1973 to create a Class E
CB service at 220Â MHz, which was opposed by amateur radio
organizations.<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-6" target="_blank">[6]</a></sup>
and others. There are several other classes of personal radio
services for specialized purposes (such as <a title="Remote control" href="https://en.wikipedia.org/wiki/Remote_control" target="_blank">remote
control</a> devices).</p>
<p>During the 1960s, the service was popular among small
businesses (e.g., electricians, plumbers, carpenters), <a title="Truck driver" href="https://en.wikipedia.org/wiki/Truck_driver" target="_blank">truck
drivers</a> and radio hobbyists. By the late 1960s advances
in <a title="Solid state
(electronics)" href="https://en.wikipedia.org/wiki/Solid_state_%28electronics%29" target="_blank">solid-state</a>
electronics allowed the weight, size, and cost of the radios
to fall, giving the public access to a communications medium
previously only available to specialists.<sup><a href="https://en.wikipedia.org/wiki/Citizens_band_radio#cite_note-ind-7" target="_blank">[7]</a></sup>
CB clubs were formed; a <a title="CB
slang" href="https://en.wikipedia.org/wiki/CB_slang" target="_blank">CB slang</a>
language evolved alongside <a title="Ten-code" href="https://en.wikipedia.org/wiki/Ten-code" target="_blank">10-codes</a>,
similar to those used in <a title="Emergency service" href="https://en.wikipedia.org/wiki/Emergency_service" target="_blank">emergency
services</a>.</p>
<p style="margin:0.5em 0px;line-height:22.4px;color:rgb(37,37,37);font-family:sans-serif;font-size:14px"><br>
</p>
<p style="margin:0.5em 0px;line-height:22.4px;color:rgb(37,37,37);font-family:sans-serif;font-size:14px">Fonte:
Wikipedia</p>
</div>
<br>
</div>
<br>
</div>
<br>_______________________________________________<br>
CLUSTER mailing list<br>
<a href="mailto:CLUSTER@radio-amador.net">CLUSTER@radio-amador.net</a><br>
<a href="http://radio-amador.net/cgi-bin/mailman/listinfo/cluster" rel="noreferrer" target="_blank">http://radio-amador.net/cgi-bin/mailman/listinfo/cluster</a><br>
<br></blockquote></div><br></div>