Ground; Method Of Cleaning Radiotron Prongs; Antenna Installation (Indoor) - RCA Radiola 17 Service Notes

The antenna should not cross either over or under any electric light, traction or power line and
should be at right angles to these lines and other antenna. It is desirable to keep the lead-in a foot or
more from the building where possible. When an outdoor antenna is used it should be protected by
means of an approved lightning arrester, in accordance with the requirements of the National Fire
Underwriters' Code.
(5) ANTENNA INSTALLATION (Indoor Type)
"Where the installation of an outdoor antenna is not practical, satisfactory results may generally
be obtained by using an indoor antenna consisting of about 25 feet of insulated wire strung around the
picture molding or placed under a rug. In buildings where metal lathing is employed satisfactory
results are not always possible with this type of antenna. Under such conditions various arrangements
of the indoor antenna should be tried to secure satisfactory results. An indoor antenna is not as
efficient as a properly installed outdoor antenna.

(6) GROUND

A good ground is quite as important as the antenna. No specific recommendations can be given
in this matter as conditions vary in different locations. Water and steam pipes usually make good
grounds. G-as pipes usually make poor grounds and, as a rule, are to be avoided. If neither water nor
steam pipes are available, a pipe or metal rod may be driven into the ground to a depth of several feet.
The success of this type of ground depends upon the moisture present in the soil. The ground lead
should be. connected by means of an approved ground clamp to a section of pipe that has been scraped
and thoroughly cleaned. The connection should be inspected from time to time to make certain that a
clean and tight electrical contact exists between the clamp and pipe.
It is recommended that the service man experiment with various grounds, and employ the one
giving the best results. Radiola 17 is capable of receiving over good distances when connected to an
efficient antenna and a low resistance ground.
Figure 6—Method used to clean Radiotron prongs.
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