Service Data Types
The service data on the Vintage Radio Service Data DVD-ROM
and available through the Instant Downloads service may be one of the
This is an original manufacturer's service sheet or manual. This varies from a large service manual at one extreme,
to a preliminary data sheet containing little more than a circuit diagram and alignment information at the other end of the
scale. Most are somewhere between the two extremes, and give adequate information for a reasonably experienced engineer to use.
Most restorers regard Trader sheets as the best source of information. Trader sheets generally contain a clear
circuit diagram, separate parts list, alignment instructions, typical voltages, tuning drive restringing, production
modifications and variations etc. Most have from 2 to 6 pages.
These sheets were published in a rival publication to the Trader. They are generally a little less comprehensive
than Traders, and the layout is not so friendly. However they covered many sets that Trader did not, and the information
is adequate for most purposes. Most are 2 or 4 pages.
These sheets were published in the 1930s and are quite similar in content to the ERT sheets. They cover some sets
from an earlier period than Trader or ERT sheets. I believe this publication became ERT during or after the war.
Most are 1 to 3 pages, with wartime data mostly 1 page.
These sheets were published in another rival publication - one which could not make up its mind what to call
itself! The sheets were generally described as product reviews, yet they concentrated more on the circuit operation,
adjust and alignment etc., than on the product performance. The information is a little more limited than ERT sheets.
Most are 1 or 2 pages.
Radio and Television Servicing
These famous burgundy books were published from the early 1950s. The amount of data included varies but it is
generally fairly minimal, often just circuit diagram and basic alignment notes. I have generally included R&TVS
data when nothing better is available - on the basis that something is better than nothing. The number of pages varies
but the majority are 1 to 4 pages.
Circuit Diagram Only
For a few sets, all I have been able to obtain is a circuit diagram. All circuit diagrams include component
values (either on the diagram or in a separate table), because I feel that circuit diagrams without component values
are not worth including.
This is used for data from other sources, such as magazines or books, redrawn circuit diagrams, etc.