Camp EvansOral HistoriesInterviewee: Claire L. FarrandInterviewer: G. H. ClarkDate: April, 1943 Place: unknown Media: Hand-typed notes |
NOTES ON THE WORK OF ROY A. WEAGANT
with special reference to the static eliminator.
Dictated to G. H. Clark April, 1943
by Claire L. Farrand
1. Farrand came with Marconi Co. in 1911.
Was opr at Wanamaker’s station, Philadelphia. Worked as second opr.
Under Tom Appleby.
2. Farrand had an amateur station, "WN", at Phil.
3. In 1908 Farrand was relief operator at the U
W T station at the Bellevue Straford, "BS". They had gap in aerial,
spark coil, coherer.
4. Farrand was sent out on the USS UTAH when she
made her trial trip, with Marconi app. On board. Then (1911) to Wanamaker’s
station, at Phil. Sarnoff at Wanamaker’s NY store then. Sarnoff
"clipped" his dashes, the characteristic of English operators who were
rapid senders.
5. Was present at Wanamaker’s when the ard wireless
telephone was tried out, 1913.
6. In 1911 Ferrand was sent to Sagaponack as releif
operator; thence to MRI, New York, 1911-1912, working under J.M. Sawyer,
as ship inspector. Sarnoff was chief inspector at that time.
In 1913 Ferrand went to Aldene.
7. In 1913 Weagant was in charge of design; Shoemaker
in charge of research. Farrand was asst. to Shoemaker. Farrand
helped Weagant when he tested out the "little black box" that Armstrong
brought to the MWTA factory for demonstration of regeneration.
8. Weagant, in 1913-1914, had in mind the use of
loops for receiving, using the Tesla idea of rotating field. Farrand
had been testing out a Bellini Tosi direction finder, with two triangular
loops with common apex, at Aldene, 1914.
9. Through 1913, 1914 and 1915 static was a common
matter of discussion, Weaant leading the discussion. Shoemaker did
not bother with this very much, but Farrand, being more practical by nature,
was much interested in this work, and soon grew to be Weagant’s chief assist
in the static experiments.
10. The very first experimental work done consisted
of stretching a wire between the towers of the MWTA factory, with loading
coils inserted in series in this overhead wire. The wire was 300’
long, 150’ high. Weagant had the idea that the loading coils would
lessen the static. Farrand does not know (today) what was his theory
on this matter. Anyway, the experiment was unsuccessful.
11. The next test was along the line of shielding.
He used the same load coils as before, but shielded them. The antenna
was grounded at both ends. Again the results were nil. (Note
G.H.C. This agrees with statement of RAW, filed elsewhere, that his
first tests were along the Dyckman cage idea, which was the basis of an
IRE paper RAW heard)
12. Next was considered the idea of using a loop
antenna, which form of antenna was coming into use at the time. Weagant’s
idea again was to shield this. A loop about 3’ square was used, with
multiple turns, and this was shielded by wires, and again by plates, placed
around it. This was 1915, about the time that the Kolster loop came
into use. Again the work proved resultless.
13. Then the work stopped for a time, and Weagant
and Farrand went into a huddle as to what other way could be devised for
using loops, so as to receive a signal and cut out the static. Farrand
spent many evenings at Weagant’s home on 5th St., Roselle, discussing the
problem.
14. The next step was in connection with a Bellini
Tosi direction finder, which had for some time been under test at the Aldene
factory. The multi-turn "Kolster" loop was abandoned.
Again Weagant reverted to the idea of creating a rotating field in such
a way as to obtain the desired separation of the two types of wave, signal
and static. Farrand suggested that the two single loops of
the Bellini Tosi device be separated (instead of placed with the common
apex as normally) and placed geographically separate; in this way Weagant’s
rotating field idea could be attained. Because there would be a difference
in the phase of the currents generated in the two loops. Work was
being done at that time with Clifden, on 6000m., as the test transmitter,
and if the coils were to be put ¼ wave-length apart this would mean
a distance of 1500m. between them. Weagant then decided to try
this out at Belmar.
15. Belmar at this time had tow large loops erected with the tall cylindrical masts as supports, for a long-wave Bellini Tosi system. These two coils were at right angles, with a common apex. This was in the summer of 1915. The first test was with the two loops as they were originally placed, i.e. with common apex. They tried this, connecting the two loops in opposing effect, and the static balanced out. They then knew that if they placed the loops apart, they would get a phase difference which would produce the signal, and still balance out the static. It worked! Then they knew they had something! The original test, where the static balanced out, and signal as well, was as shown at "a"; second test, where static still was balanced out, but signal came in, was at "b". On trying to find out what caused this effect, they finally agreed that it must be due to a signal coming from overhead.
16. Said Farrand to Clark on dictating the above: "Weagant may have had this idea in his head before this test, but this was the first time that I got this idea".
17. The next step was to put two large, rectangular loops up, using the 400’ poles. The circuit was: (Drawing needed) but the loops had too high a natural period for such tuning, so the circuit was changed to a parallel condenser form, as in the secondary of the Marconi valve tuner.
18. Finally, after they learned to tune the circuits, Clifden signal was heard loud, with static cut down to a minimum. "This was the most marvelous experience in my whole radio life" said Farrand.
19. The "loops in the antenna" used in the first Aldene tests were "Pupin coils", ordinary receiver coils in the antenna; the next Aldene tests were with small multi-turn loop, and later small Bellini Tosi triangular turn loops with a common apex. Then the Belmar tests; first with large B/T d.f. coils, with common apex, and lastly with coils separated geographically.
20. Later, tests were made at Aldene with separate
loops, for 600 m., but this was done after the Belmar tests had
been carried out, which was in the summer of 1915.
21.
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