Wax nostalgic about and learn from the history of early electronics. See articles
from QST, published December 1915 - present (visit ARRL
for info). All copyrights hereby acknowledged.
When
the caption for a photograph in a 1931 article refers to an "antiquated"
motor, you can be sure you're looking at a really old motor. Indeed
it does look very old. Whenever I see vintage photos or films of
electrical / electronic apparati[sic] and operators, I always look
for safety issues like no eye protection while soldering or when
using powered tools to fabricate enclosures, lack of protective
shields around electrical connections and mechanical drive mechanisms,
wearing of inappropriate clothing near rotating machinery, etc.
In this case you can see a very long, totally exposed drive belt
running between that aforementioned antiquated motor and DC generator
that it drives (to power the transmitter). The author mentions how
the floor shook while it was running. I wonder if the filaments
were shaken enough to introduce the vibration frequency into the
audio (mircophonics)? Ah, the not quite so good old days.
Amateur Radio Stations
VE2CP- The McGill Radio Association, Montreal, P. Q.
By John Stadler, VE2AP
The story of amateur radio at McGill University goes back
nearly to the time when all of us were dressed in shorts and sailor
hats. Rather than disturb the old records let us just mention that
once upon a time the call was 1OAU and then 2BJ. I have never known
10AU and neither have any of the present gang, but some of us are
privileged to have known 2BJ. Suffice it to say that it was long
ago.
VE2CP really has no complicated and extensive apparatus
to boast about. A station description would be amazingly short when
sticking to technical details, but the story of how the present
outfit came to be would be very interesting were it possible to
record the heart pangs and anxiety of the originators of the present
station.
The location is in the d.c. lab of the Engineering
Building. The partition separating the radio shack from the very
"terre-a-terre" direct current equipment was donated by the Electrical
Department. As a matter of fact, had no assistance been given by
the Department in furnishing panels, rheostats, etc., possibly VE2CP
could belong to somebody else. However, let us leave the "if" out
of the picture, because "if" we had money, we would all own at least
a pair of 861's.
GENERAL VIEW OF VE2CP AS SEEN BY
THE OPERATORS SHOWING TRANSMITTER AND ANTENNA TUNING PANEL
The transmitter is of the tuned-plate tuned-grid type with a
UX-852. The filament voltage is obtained from the 110 d.c. mains
by a potentiometer arrangement. Although one tube was burnt out
the method is the only one to be used in the present case. The plate
voltage is obtained from a 3-kw. street lighting d.c. generator.
The rheostat mounted beside the switchboard on the operating position
serves to control the output voltage within certain limits. The
maximum obtainable is about 1500 volts, and we venture to say that
the regulation is good! The driving motor is somewhat antiquated,
we will admit, and also imparts to the flooring a quite definite
frequency (which we notice personally) but judicious use of rubber
pads on the table and transmitter have removed all traces of oscillating
coils in the emitted signal. Furthermore the use of such apparatus
makes the station look the more formidable and it appears that the
powers of amateur radio are thus magnified tremendously.
THE COLOSSAL 3KW PLATE SUPPLY GENERATOR
(ON LEFT), ANTIQUATED DRIVING MOTOR (RIGHT), AND FORMIDABLE SLATE
PANEL (REAR)
The receiver is a three-tube affair using a 224 as space charge
detector and two 227's as amplifier. These are resistance and transformer
coupled. With high voltage on the plate of the 224 a very good signal
level is maintained. One drawback in reception at VE2CP is that
the station is not over a quarter of a mile from a local broadcasting
station. The result is that even with a wave trap some music at
times filters along with the signals and makes operating more enjoyable
- we don't think.
Back to the high voltage we go. The filtering scheme is very simple.
Being strong minded, we immediately fell for the brute force idea.
One-half microfarad each side of a 3-henry choke gives fine results
and when the combination of radio frequency and floor frequency
does not exist, the note even locally is a very fine grade of pure
d.c.
The erection of the apparatus in the station was carried
out by VE2BH and VE2CP jointly. Jointly is the word, because wielding
a heavy hammer and making holes in a sound brick wall requires a
little bit of cooperation. By the way, drilling a marble panel even
with a power-driven drill presents its difficulties to the inexperienced.
As engineering students we are taught why the holes in the walls
are drilled, what size they must be and how much permissible load
can be carried, but of the delicate operation of actually drilling
the hole we know little until the fingers are sore and arm well
nigh out of joint.
GENERAL VIEW OF VE2CP AS SEEN BY
THE ONLOOKERS
The present gang of licensed calls operating at VE2CP areas
follows: VE2CU, VE2CO, VE2BO, W8BOM, W6ARA and a whole lot of licensed
operators whom we shall not mention. The station has been helping
in traffic work by trying to pile up the high score for the VE2
district. They have done nobly and deserve our thanks.
Before
we bring this description of VE2CP to an end, we want to justify
our references to the gigantic expanse of apparatus. Remember that
the shack is screened by a wire partition. Now this looks like a
cage, and the first idea that springs in the mind of onlookers is
that we are monkeys. That is, we are lowered in zoological scale,
and since our feelings on the matter are very sensitive we have
to destroy the impression by the process of neutralization. We feel
that we have succeeded, as starting up VE2CP is no mean affair.
To begin with we enter the d.c. lab and proceed up to the
large slate panel covered with powerful looking switches, meters
and circuit breakers. We close the two 24-inch switches after closing
the two-odd hundred-ampere circuit breakers. The "juice" is now
running up to the secondary panel on the motor frame. To this panel
we go, close the 6-inch switch and proceed to bring the motor up
to speed with the control resistance. Then we turn on the oil on
the generator. A third panel on the wall behind the generator enables
the power output to be sent either to the shack or to the radio
lab upstairs. Well, we throw the switches to the right. Then we
insert the wall plug that gives us 110 d.c. for the filament circuit
and for the generator field circuit.
Here we are in the
shack with the power arriving to our switchboard - just fancy, our
own switchboards! Close the right hand switch and presto! the filament
lights at 10 volts d.c. Close the large 6-inch top switch, then
the left hand lower switch, and that's all. CQ CQ CQ de VE2CP!
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