When you see these scroll up the page for a couple more...
This old receiver belonged to the George Williams, a late friend of Howard James, who kindly passed on to me George's collection of radio bits and pieces together with the R1116.
A
nice Ever Ready portable from 1939. I think it's a model 5214
and it's most unusual, at least in the UK, as it uses "side
contact" valves. These were common in Germany and other places
but not the UK, whose manufacturers preferred octal based valves.
It came from Wimborne in Dorset.
Is the covering real snakeskin? I suspect this may have been cheaper than plastic in those days. Then again I don't recall seeing many red snakes. Perhaps they were wiped out in the late 30s when parted from their outer coverings?
An
early example of a general purpose galvanometer. This particular
type does not have a balanced needle and so must be operated in
a vertical position. As meter design improved their pointers were
balanced and the meter could be operated in any position. Compare
the design of the pointer with another
similar instrument, which although not accurate in any position
does at least have a symetrical pointer giving it better stability.
The case looks like mahogany and its construction is cheap.
The top terminals are brass and marked "0", "I" and "I0", which I assume refer to two sensitivities. The scale is marked in degrees up to 90 to the left and to the right.
There's no maker's name anywhere on the instrument and I suspect it was manufactured before 1910 and not in the UK.
Can anyone identify it and for what it might have been used ?
This
old meter is about 7.5" in diameter, that's 187mm in modern
money. Like many early meters this instrument must be operated
in a perfectly upright position otherwise its pointer will not
rest at zero.
It's unusual in that it doesn't need a shunt as most ammeters do. The terminals are connected to a very heavy coil of wire comprising around four turns wound round the mechanism which uses an aluminium damper inside a tube. Not much chance of damaging the movement. It was made by Siemens Brothers and is probably from the first twenty years of the 20th Century. Maybe someone can date it more precisely? Unfortunately there's no date written on the back of the scale.
It works equally well on DC and AC.
This
is the Philips Model N4418, their top of the range open reel tape
recorder in the 70s.I picked it up for £10 from the local recycling centre after filling in numerous forms, presumably to imdemnify the workers, local council officials, the UK Government and Brussels beaurocrats if I accidentally electrocuted myself when plugging it in. Absolute and utter nonsense! What's the world coming to?
Fortunately the mains lead was intact, tucked into a little compartment. Were the recycling people breaking some sort of law not cutting it off!
£10 was a lot of money considering the showroom was not available for demonstrations, but I was very pleasantly surprised when I plugged it in, and switched it on, to find it was in perfect working order.
Even the perspex cover is intact. The only faults I could find were a slipping belt on the tape counter and a faulty bulb in the RH output meter.
Considering that the price of the machine when new was about 50% of a small car such a mini, £10 wasn't bad. As the chap said when he quoted £10, "collectors are after them". Well one was and I'm very pleased I coughed up the cash.
An early
horn loudspeakerStanding on a mahogany base and having a lacquered brass adjuster and connectors, this loudspeaker probably dates to around 1922 or 1923. It was made by S G Brown who were a leading company in the early days of audio amplification, particularly of crystal sets, using magnetic amplifiers, before valves were commonplace.
This example, which has a horn opening of 12" and stands 21" high, appears to have been restored, or at least repainted. The impedance of the energising coil is 4000 ohms and would have been ideal for connection to a crystal set in place of the usual headphones.
Newer than
my usual purchases, this Stella "All Transistor" ST404T
dates from August 1960. It looks as if it just came out of its
box for the first time and worked perfectly when three "AA"
batteries were fitted.
This is part
of a WWI Trench Transmitter. Encapsulated within the wooden box
is a step-up transformer. The metal fittings on the top are parts
of a buzzer which interrupts the battery supply. There is an iron
stud protruding slightly in the centre of the top panel which
is magnetized when current passes through the transformer primary
winding. This attracts an iron spring (missing) which carries
the current. As the spring moves toward the iron stud the current
is broken and the spring returns to its current carrying position,
from where the cycle repeats.
The high voltage produced by the transformer secondary winding provides the energising current for the morse code transmitter.
A more complete example can be seen by clicking the picture.
As you can see this
is a RADIOLUX. What's a Radiolux?
Well it's a cure-all magic box known generically as a "Violet Ray" machine.
This model is quite a late example, probably dating from the early 1930s and works from 110 volts. Not as you may think an American supply voltage, but one dating from pre-war days when England had an almost infinite variety of mains voltages, both AC and DC.
Only one glass tube seems to be present but originally there would have been a selection, each producing a marvelous puple glow accompanied by a fizzing noise from the discharge of several thousands volts.
Click the picture and see another model.
These are
two similar examples of a mirror galvanometer, a very sensitive
device for use with something like a Wheatstone Bridge.
The greater the sensitivity of current measurement, the greater the accuracy of measurement of resistance for example.
I bought these from a chap in France, where I imagine they were used in a Physics Laboratory. This particular design was invented by a chap named D'Arsonval.
The mirrors are presently detached but normally would be suspended so that they are visible through the front window. A light source can be directed at the mirror, which reflects a spot onto a remote scale. Inside the case is a horse-shoe magnet and the flux from this reacts with the field developed by current passing through a coil mounted with the mirror. The result of this interaction is a mirror deflection.
This is
an English galvanometer, probably also from a Physics Laboratory.
This type operates as an ordinary moving coil device and has a
pointer which deflects when current flows through the instrument.
Both the pair above and this model rely on accurate setting up by altering the height of their feet.
This
meter measures a little over 2 inches across and attracted no
interest to buyers, being described as WWII. If it had been correctly
identified as WWI, I might have had to pay ten times the sum it
went for.
It probably dates to 1917 or 1918, as before then it would have been inscribed "RFC" rather than "RAF".
The case is heavily nickel-plated brass and it reads 0-0.5Amp.
It once lived at the W/T Stores Depot, RAF Kidbrooke in Kent and it has No.4494 marked on the dial.
It has only three valves and as you can see the minimum of controls. It has a multi-tapped mains input and was therefore universal, at least as AC mains was concerned.
1920s home-built radio chassis
More 1920s radio components
Heathkit Grid Dip Meter
Bush AC34
Variable high voltage power supply
Vintage variometer
Morse reader
Another HP VHF Oscillator
HRO; "much modified"
The HRO was available in large numbers after WWII and was used as the basis for pepping-up using modern valves by many radio amateurs. The awkward tuning arrangement wasn't important when looking over an amateur band. All you needed to know was the band edge settings on the dial. Actual frequency was relatively unimportant. The resetting accuracy using the dial's vernier reading was very useful.
The design of the HRO must have been good as both the Japanese and the Germans copied it during WWII.
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