Evening star. [volume] (Washington, D.C.) 1854-1972, 1930-02-02
PPARENTLY fearful of an
1 adverse effect on the radio
market bV the recent an

~ uIdHhcb ny LIlC TSCSnb an
4 A nouncement of the coming
of the five element pentode tube
the Radio Manufacturers ASsoci-
alton, which comprises virtually
all the important radio set max
erS in the country, has been quick
to answer the claims of what the
tube will do.
A few days after the newSpa-
perS of the country had heralded
the advent of the pentode and
outlined its advantages over the
present three and four element
tubes as claimed by the manufac-
turer, the association issued a
statement denying that the tube
is new or revolutionary or that it
will give better service. The state
ment was prepared by Walter E.
Holland, a Philadelphia radio en-
gineer, who is serving as director
of the engineering division of the
Radio Manufacturers Association.
There is nothing new or revo-
lutionary about pentodeS," de-
clared the statement. mo i'm
provement in performance can
now be obtained with pentodeS
that cannot be had with present
tubes. A given result is possible
with less tubes, using pentodes,
but it is unlikely that the cost of
a complete radio receiver would
be any less.
"The pentode tube has long
been known abroad and has
found limited commercial use
there, especially in England. Many
radio-receiver and vacuum tube
engineers in this country have
experimental with this type of
vacuum tube and are thoroughly
familiar with its characteristics
and possible applications.
"The pentode power tubes used
abroad have greater Sensitivity
and, therefore, provide higher
amplification per stage than our
triode power tubes. This makes
it possible to eliminate a state Of
audio application and work
from the detector directly into a
single power stage without over
loading the detector or the radio
frequency amplifier tubes. An
other advantage is that it is pos
Sible with pentodes to obtain
greater undiStorted output where
the plate voltage is limited, as in
battery receivers and receivers
for operation on the 110-volt di-
rect current supply used in GER
tain sections of a few cities.
Against these advantages the
pentode has a number of diSad-
vantageS. It is a most difficult
tube to manufacture with uni
formity, owing to its completely
and to the fact that it must be
exhausted to an extremely high
degree of vacuum. Non-uniform-
ity of pentodes will make greater
differences in the operation of a
radio receiver than with tubes of
the present type. 1t Is inherently
a high-coSt tube"
All precincts have been heard
from, and the National Broad
casting Co. has analysed the re-
turns commenting on the memo
rable exchange of radio programs
with Europe on Christmas day
and the day after. The result.
throw an interesting light or
Americas taste in radio enter
tainment and provide valuable
information which can now bC
used in designing similar fea-
lures.
Among the thousands of letter.
which arrived in every mail since
Christmas, there were many bit.
ter complaints. AS these wer,
read by program experts, they re.
GREETED temporarily the predomi
nance Of popular music in Ameri
cas- contribution to Europe'S "a
dio Christmas. But now the fina
comparison has been made, ant
the N. B. c. discovers that al
overwhelming majority approves
its selection of program materia
for the international exchange
Actual count reveals that IL per
sons considered the program al
excellent representation of Amer
lean music for every single on,
who reSentS the intrusion of Jazz
Returns from abroad, from
England, Holland and Germany
where the American program
were broadcast clearly over ma
tional networks, are unanimousl,
enthusiastic in praise Of the ma
terial selected.
Foreign listeners urge that Sucl
exchanges of entertainment b
made more frequent, and specifi
cally ask to hear more of sucl
noted American radio stars a
JeSsica Dragonette, the Reveler
Quartet, Elizabeth Lennox AM
the Salon Singers. Whey ais