New-York tribune., 1922-12-17
New Rectifying
Tube of Novel
Construction
Invention of Fl. p. Donle To
Be Described and Will BE
Demonstrated at /. r. Z.
Meeting on Wednesday
Tube Has Sodium AnOde
Results Obtained From Test
Said to Equal Those of
Regenerative Receiver r

A new type vacuum tube OF rev0iu-
tionnry design has been produced oy
H. p. Donle. n well-knOwn radio en-
g,neer. after years Of research work
Tbe tube. which Is based upon the prin--
ciple Of ionization, has been named
tbe Misunderstanding Deteetor be-
cause OF its inability 70 produce os-
eillations. 4.
II will be demonstrated and de-
scribcd In detail. In a special paper
which Mr. Donle is 20 read before tne
Institute Of Radio Engineers In the
Engineering Societies Building on
West Thirty-ninth Street at S:l5
o'clock Wednesday evening, December
20. This meeting will be open 70 tne
general public.
In conjunction the new tube Is en-.
tirely different from any other type OF
vacuum tube. II consists OF O straight
wire flament. which passes out Of the
tube and continues as a heating coll
underneath a bowl-shhped anode com
posed of a piece Of metallic sodium.
Around the filament. inside the tube
there is trough-shaped collector
electrode which controls the ionization
action set up when the anode is heated
by the hlament coil.
Tube Is Very Sensitive
The tube has been tried in n number
Of receiving circuits in various loeali-
ties around this city, and according 10
reports is very steady and sensitive In
its action. John V. l.. Hogan, we'll
known consulting radio engineer. In
speaking Of it said; II have tried out
these tubes and found their sensitive
ness in a plain receiver II anything a
little higher than that Of good U. V.
POI In a high-grade regenerative re-
ceiver"
One Of the poeuliarities Of the tube
Is the fact that II the telephones are
placed in the collector electrode circuit
instead Of in the anode circuit, signals
Of practically the came intensity arc
received.
Experiments With II have shown that
the best circuit for II Is tho regulation
loose-coupled two circuit tuner. A
potentiometer Is shunted across the I'll
ament battery and one side Of the sec
ondary circuit is connected 20 the vari-
able arm Of the potentiometer, while
the other side Of the secondary Is con
nected TO the collector electrode. The
flament Is controlled In the usual man.
ner by rheostat
The anode circuit runs from the
metallic sodium to the telephones and
from the latter 20 the positive side OF
the B battery, while the negative ter
minal Of the battery Is Joined TO the
negative side Of the storage battery
No High Frequency in Plate
The collector eltctrode, which 4,
practically in the same position as the
grid Of an ordinary vacuum tube. does
not entirely inelose the flament Ex-
periments have shown that when the
electrode did cover the flament there
was no clectronic action between the
| flament and anode.
Very careful Ind detailed expert.
ments are said 20 have proven that
there Is absolutely no high frequency
currents in the plate circuit OF this
tube, and consequently regenerative ae-
| tion with IL cannot be obtained. In
view Of this circumstance and the
stated fact that 10 Is as sensitive as
the ordinary regenerative receiver, Il
would seem 20 be an ideal tube foi
broadcast receiving.
At the present time II has 10 be In.
serted in the regulation vacuum tube
socket In an inverted position, but fu.
ture tubes will be so designed that
they can be used In the ordinary way