A common problem is collectors have is establishing
how old sets really are. No dating method can ever be exact, apart from referring
to records from the time (such as service data publications), because different
manufacturers may have taken different periods of time to update their tuning
scales or utilise the latest valves. However, looking at all the clues, you
should be able to estimate the age of a set fairly accurately.
Various methods are given on this page. Further
ideas and amendments will be added when the site is updated. Additions and corrections
There is more information on this subject at
Look out for the following stations marked on the dial
- Pre-war (1920s - early 1930s) - No station names but dials usually
calibrated in degrees or metre numerals only.
- Pre-war (Mid 1930s+) - Nationals and Regionals (1935+). Welsh (after
- Wartime - Home Service and Forces.
- Post-war (1945+) - Light Programme (introduced in 1945).
- Post-war (1946+) - Third Programme (introduced in 1946 on 203.5 metres
- Post-war (1950+) - Third Programme (now on 194 metres medium wave)
- Post-war (1955+) - Light Programme on 89.1 Mc/s (VHF sets only -
new FM band introduced in 1955)
- Post-war (1967+) - Radio 1, Radio 2, Radio 3 and Radio 4 introduced
This information was found somewhere
on the Internet - but unfortunately I cannot remember where!
Look at the type of valves used
As new types of valve were introduced, manufacturers
generally included them in their new models fairly quickly. There is a good
two-page spread in the "Radio Radio" book, picturing many of the valve
types with dates. The following is a summary of some of this information.
Obviously some manufacturers would have taken
longer than other to introduce new devices, so sets may be somewhat newer than
this information would suggest. However they couldn't be older!
- 1922-1925 - valves had metal British 4 or 5 pin bases and a "pip"
on the top where the air has been evacuated
- 1925 - "Pipless" valves with Bakelite bases were introduced
- 1931 - Metalising on the outside of the glass (generally with a protective
layer coloured grey, gold or red)
- 1933 - British 7-pin bases
- 1934 - British 9-pin bases, side-contact bases and Acorn valves
- 1936 - Magic Eye tuning indicator valves
- 1937 - International Octal bases
- 1938 - British Octal (Mazda Octal) bases, Loctal bases
- 1946 - GT Octal (as International Octal but with smaller tubular
- 1947 - B7G bases (small all-glass valves used in battery portables
- 1948 - B8A 8-pin "Rimlock" bases (original type having
metal surround), as used for UL41 etc.
- 1951 - Noval 9-pin base - familiar 9-pin valve base, used for EL84
- 1953 - All-glass B8A "Rimlock" bases (as 1948 B8A but without
Look at trends in design
As with other ideas on this page, design trends
can be little more than clues to the age of a set. Some manufacturers took longer
than others to introduce new ideas. This information is summarised from the
book Radio Radio. Further information and corrections are welcomed.
- The 1920s are quite difficult to summarise on a page like this. Sets
were generally TRF and, with the exception of portables, tended to have separate
loudspeakers. Superhet designs began to appear towards the end of the decade,
but were very expensive luxury items.
- 1930 - McMichael release the first set to feature an illuminated
"full vision" tuning scale, with a cord-driven pointer moving behind
a glass scale. Manufacturers started to produce more sets with self-contained
- 1931 - Philips introduce the Superinductance range of high quality
- 1932 - Manufacturers started to introduce AC/DC "universal"
sets, instead of separate AC and DC models. The vast majority of sets now
had built-in speakers, many also has connections for an extension speaker.
- 1933 - Visual tuning indicators (such as a small light bulb which
varied in brightness) were introduced. QAVC appeared on some top-end sets
to overcome the problems with normal AVC.
- 1934 - The vast majority of sets were now superhets. Midget sets
started to appear, of both UK and USA origin. "Clock-face" dials
(round dial with single pointer, wavelengths only, separate station chart
in tray beneath set) and "Aeroplane" dials (round with double-ended
pointers) were introduced.
- 1935 - Full-vision tuning scales become commonplace. The first "mono-knob"
design was introduced by Decca. The term "high fidelity" started
to be applied to top-end sets by some manufacturers.
- 1936 - The "Magic Eye" tuning indicator was introduced.
Philips and Mullard introduced the first of their their Mono-knob sets.
- 1938 - Push-button tuning introduced by several manufacturers (either
mechanical, electromechanical or individual preset switches).
- 1940s - There were less significant changes in the 1940s that can
be used for dating purposes. The main landmarks were in the introduction of
smaller valves, as detailed above. In the first half of the decade, Britain
was at war and very few sets were produced, and during most of the second
half of the decade the country was recovering from the serious financial impact
of the war.
- 1950 - Manufacturers started to concentrate more in the "second-set"
market, with smaller sets intended for use in kitchens and bedrooms etc. Mains/battery
transportable were becoming more popular. Magic Eye tuning indicators were
making a comeback.
- 1951 - Radio Luxembourg moved to 208 metres MW.
- 1953 - Elliptical speakers began to be used more frequently in smaller
sets. Battery portables aimed at the female market became more popular.
- 1954 - PCBs started to be employed in an increasing number of sets.
A few manufacturers started to include VHF bands on their sets in readiness
for the launch of this service in 1955.
- 1955 - VHF was launched in May, and many VHF only and VHF/MW/LW sets
- 1956 - The first British transistor set - the Pam 710 - was released.
- 1957 - Oversize round tuning controls became much more popular.
- 1960 - The flood of cheap transistor sets from the far east began.
The first transistor models to include the VHF band were introduced.
- 1964 - Radio Caroline, followed by other pirate stations, began broadcasting.
- 1965 - VHF/FM stereo launched.
Look at component date markings
The electrolytic capacitors, in particular the
main smoothing capacitor, are often marked with manufacture dates. The reason
for this is that capacitors required reforming if they had not been used a certain
period of time. The date allowed the first user of the capacitor to conform
whether or not it needed reforming before applying power.
It is likely that the radio was manufactured
a few months after the date on the capacitor, so you could probably assume the
set was made in either the same year or the following year to the capacitor
However it is possible that the capacitor may
have been replaced - and the replacement could be newer or older than the original.
Or the capacitor may have been in storage for a longer period before being fitted.
Although not that relevant to most vintage radio
equipment, many semiconductor components (in particular ICs) contain a four
digit date code. This will probably be below the type number of the part. The
first two digits indicate the year, and the second two indicate the week. So
a component marked 7123 would have been made in week 23 of 1971.
Decode the model number
Some manufacturers give clues in the model numbers
of their products. I will see if I can establish some more of these for future
updates to this page. If anyone knows of other model numbers that can be decoded
in a meaningful way to establish the date, please let me know.
It should be noted though that many of these
manufacturers would happily break their own rules, so this information should
be regarded as a clue only.
With some post-war Ferranti sets, the last two digits of
the model number, reversed, appear to give the year that the set was released.
In some cases the release date shown on the service data is one year later,
so the model number may be indicating the design year rather than the release
year. For example, models 215 and 615 were both released in 1951.
I don't know how useful and consistent this is though -
would anyone care to comment?
Mike Izycky offers the following useful method for dating
GEC sets are very easy to date, with only one or two
exceptions. Up to 1949 the first two digits of the model number are the
model year. After 1950, the model year is the sum of the first two digits
added to the last two digits, so:-
BC5639 = (5+6)+39 = 50, so the set is 1950.
This doesn't work with the later models having three digit
With many McMichael table sets, either the first two digits
or the last two digits of the model number will be the year. This doesn't
seem to work with console sets and radiograms though.
For example, model 371AC was released in 1937, model 493
was released in 1949 and model 153 was made in 1953.
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No part of this website may be reproduced in any form without prior written
permission from Paul Stenning.
All details are believed to be accurate, but no liability can be accepted for
The types of equipment discussed on this
website may contain high voltages and/or operate at high temperatures.
Appropriate precautions must always be taken to minimise the risk of accidents.
Last updated 14th April 2006.