| Hi All! March
6, 1999 was a great day for me. Postman give me the pack from
Oregon (USA) long awaited, contains my young's dream! BW finally
arrived!
Radio looks great at first sights
and much better when I see the serial number: 1491!!!
Looking to transistors's case I have understand that this
BW was produced around 1972...or before.
The only evident external "signs of time" is some
scratchs over S-Meter lid and a peels on the right back corner.
Otherwise, chrome is in good shape and overall, Oregon (as
intend to nicknaming my BW) don't show high worn signs. The
only place where I've find some quite bad corrosion is in
the internal floor plan...no chart log on top.
To have access at circuit board,
there's two simple "coin-screws" kind retainer on
the back door, a must for '70 style!
The battery holder is fixed on the
back lid of radio and is so BIG (see photo), for six "C"
cells type battery. However, due internal regulator, Oregon
works well with a 6Vcc external regulator as one 12Vcc too.
BW consumption is low (35 mA average), so battery's charge
can last VERY long. A real portable DXer!
Opening the back lid, you face the
whole radio circuit board:
In effect, apart the good idea of
put almost all components over a single board, BW circuit
construction suffer of some not so looking-good soldering
So, if you have to buy a BW better is that
it works and well, or that is could be a real cumbersome problem...!!!! |
Circuit board is more "European"
style than Japanese or USA...some ideas was taken straight
from Grundig's layouts.
Tuning was developed from two solid
variable capacitors, directly clamped to the tuning wheels...no
band selector, no weak corded tuning mechanism!
But what get eyes attention in circuit
board is the Antenna Trimmer mechanism:
In my (short) radio experience I've
seen many strange devices, but this is one of the strangest...but
effective too! Wadley's radios type need a good preselective
action to tune in right signals and not spurious from some
harmonics...For example, FRG-7 sets solve this problem with
a complex bunch of commuting coils and a separate variable
capacitor.
BW haven't so spare place to achieve same results...so solution
is a single variable induction three-stages coil, which sections
are commuted from two micro-switches played from coil tune
knob's action! What a HECK!
More classic the IF stages:
A simple air-commuter for USB-LSB-AM
work, switching-in two (little) reddish MuRata ceramic filters
(on the right). MF coils are common. Less common are the up-conversion
coils, made directly "on air"...they don't give
a confortable look!
Clarify SSB mechanism is located
on the lower side of CB, just back of front cover. Instead
of a variable compensator, it use a variable inductive coil
too, like Antenna Trimmer.
AF stage is built on two OLD germanium
transistor, screwed to circuit board...newer BWs switch it
with a more effective IC AF stage. However, sound is good...helped
from an oversized power loudspeaker (AF stage give 400 mW,
LS is a 1,6 W power) too.
With full battery on-board BW is
REALLY weighted, but problem is that battery holder is not
so "holder" to retain cells in place when you open
back lid. So I have to put some adhesive band over cells to
prevent they falls into, over circuit board's elements...
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