Evening star., 1925-05-20
FIFTEEN MINUTES OF
RADIO EACH DAY
BY JOSEPH CALCATERRA.
An Rights Reserved. Repro. Prohibited.
How to Connect the "B" and &C.
Batteries TO the Receiver.

No trouble can be experienced in
connecting B and G batteries If ordi-
nary precautions are observed and
little study is given to the difference
btween negative and positive terfnl-
nails.
While terminals on dry cells are
not marked with plus and minus
signs so that it is necessary TO re
member them by their locations, the
terminals on both b batteries and &
batteries are marked plainly so that
there is no excuse for any errors in
connecting them.
r batteries can be connected in
parallel for increasing the capacity
of the unit. but this method is sell
dom used. \ method that amounts
TO practically the same thing is to
get batteries of greater capacity. b
batteries are made in different sizes
and shapes for different classes of
duty, but in the last analysis they are
very much the same.
Il Battery Explained.
A 3 battery of the 22i2 volt type
is made up of Is small dry cells
connected together in series. The
voltage of each cell being | Il volts,
the total voltage obtained by con-
Meeting them in series is equal to
22i2 volts. In the 45-volt type, 80
small dry cells are connected In
series TO give the required 45 volts.
The voltage of storage cells is ?
volts per cell, so that in storage B
batteries II cells are connected in
series to give a voltage of % volts,
while 30 cells are connected in series
TO give a voltage of A volts.
Dry b batteries have their termi-
nails plainly marked. The negative
! terminals are marked with a minus
sign. while the positive terminals are
| marked with plus signs or merely
| with the voltage of that particular
| terminal with respect TO the negative
| terminal.
/ B batteries are connected in series
| in the same way as the single dry
cells by connecting the highest posi-
! tive terminal with the negative ter
! minal Of the succeeding battery. To
| get a voltage of 40 volts use 40
! volt battery or connect two 22I2 =
| volt units i'll series. TO get voltage
| of 80 volts connect in series either
: two 45volt batteries or four 2213 :
| 135 volts connect in series eithe.
! three 45-volt units or six 2212 volt
units.
| Make Careful Connections
| Great care should be exercised in
| connecting the 3 batteries. Be sure
| that the negative B battery terminal
| is connected with the negative bat
/ terry terminal on the set and that
| the positive terminals of the B bat
teries are connected with the proper
I positive terminals on the set. If the
{ terminals on the set are not marked
| have them marked in some way. This
| may be done by using engraved bind
| ing posts with removable heads
| by means of etched terminal plates
| which can be frightened in place by
] the binding post base or they can he
engraved. If no other way is avail
able. use little pastors glued near the
! terminals and bearing the terminal
| designation.
The negative and positive terminals
are marked plainly on the C batteries
! SO that all that is necessary is to
be sure that you connect the tern1i-
nails properly.
1t is possible to operate a set with
| the A and c terminals reversed, but
the efficiency and tone quality of the
set will be poor. 1t is impossible tc
get set to operate with the B bat
| terry terminals reversed. Be sure tc
watch your battery connections and
you will save yourself a considerable
amount of trouble.
| Note: The illustrations in parts ]
and 2 of the Fifteen Minutes of Ra-
dio Each Day" series on how to con.
meet A batteries which were published
| Monday and Tuesday, were inadvert-
emily reversed. The illustration which
appeared with part l should have been
| used with part 2, and vice versa.