|Early Wireless Installation|
|This photograph shows an interesting
array of very early radio equipment. Unfortunately, the original is
small, of marginal quality, and doesn't give a clear view of the
equipment in front of the operator.
Most prominent is the large helical transmitting inductor at the top of the photo. Below this is a large transformer which provided the high voltage needed for the transmitter. The spark gap is located inside the helix, which was standard practice at the time.
A variety of receiving equipment appears in the foreground. Nearest the camera is a very large receiving coil with a single slider-type adjustment. Two binding posts on top appear to have no wires attached, so this unit seems not to be in use. Behind this is a device in an oak cabinet, with what appears to be a switch on top and binding posts on the front.
The next unit appears to be a loose coupler. This was a receiving transformer with variable coupling between the primary and secondary windings, and slider adjustments on the primary winding. The secondary was mounted on a pair of rods that allowed it slide in and out of the primary, thus allowing the degree of primary-to-secondary coupling to be adjusted. This unit may have been made by Murdock.
There is another unit, directly in front of the operator, which is partially hidden. Visible are two binding posts on top of a frame-like structure. A wire is connected to one of these that can be seen running up towards the upper left corner of the picture.
Just in front of the operator there must be a transmitting key, but it is not visible.
There is an elaborate carved railing separating the equipment from a large open area in the background. This divider would prevent the curious from getting too close to the equipment, and any potential for lethal electric shock.
Click here, or on the photo to see a much larger version. I would welcome any additional information on any of the items in the photo.
A clue to its origin comes from a photograph which appeared in a publication of the Antique Wireless Association in 1971. It is reproduced with their kind permission below.
This photograph shows a commercial station belonging to the United Wireless Telegraph Co. located in Philadelphia, circa 1911. The transmitting apparatus in both photographs is very similar, though the receivers are much different.
So, unless more information surfaces, my guess is that the first photo shows a wireless installation from the 1910 to 1915 period, which may either be a commercial station, or possibly one operated by a college or university. It was certainly not a privately owned amateur station, however.