Aircraft Radios

[Steve Smith]

Hello -

Can anyone point me to books or journal articles describing
the radios carried by the observation planes?

Thanks

[Curtiss Jenny]

Early radio development was very closely parallelled by the early vacuum tube development. Because of this, one book that may be of use to you is "Saga of the Vacuum Tube" by Gerald F. J. Tyne. It is available through Antique Electronic Supply, 6221 South Maple Avenue, Tempe, Arizona 85283, www.tubesandmore.com. This book also has a great list of references at the end of each chapter. As indicated by the title, this book is about vacuum tubes, but depending on what you are specifically looking for, it may be of some use.

This book has 9 chapters covering tubes for "The Entrance of Industrial Laboratories and Military Demands, 1910 to 1920". There is a chapter for each major manufacture of tubes in America (Western Electric, DeForest (there is a photo of him holding an aircraft transmitter), General Electric and various independants). There is also a chapter for each European manufacture by country (France, Great Britain, Germany and others).

Early radio circuitry was largely developed by the amature radio operators of the day. For this reason you may want to obtain early copies of QST on CD-ROM available from the American Radio Relay League, 225 Main St., Newington, CT 06111. Again, depending on what specifically you are looking for it may be of help.

If you can find them (at flea markets, librarys, tag sales etc,) keep you eyes open for early magazines of the day such as Popular Mechanics and Popular Science. They can also include a wealth of information for the early radios.

I think at that time all aircraft radios were morse code based. The only voice modulation method at that time was with the Alexanderson alternator, which was a high frequency (100khz) generator.

The ELT of the day was a homing pigeon, stored in a cage under the pilot's seat. This piece of trivia was made known to the Smithsonian by Arthur Ray Brooks shortly before they began to restore his particular airplane, the Smith IV.

[retread]

The RAF did install wireless voice air to ground and air to air transmitters in a few of their aircraft in the last year of the war. Although I cannot remember the squadron(s) involved. It is posted on a similar thread from about a year back. I believe it is in Harold Balfour's book "An Airman Marches".

[retread]

At least as far as the U.S. forces were concerned the BC 15-A (1918) was the first (spark gap/morse) transmitter designed specifically for use in aircraft, the Western Electric SCR 59 (1917) was a reciever used in aircraft and may also have been also specifically designed for that purpose. An interesting website to rummage through is
http://www.sparkmuseum.com/SPKTRAN.HTM
It has photos of the above mentioned sets and a number of others WW1 related.

[Barrett]

Apparently many/most German naval patrol planes carried radios from 1917 onward. I've never seen any specifics as to models and capabilities, but recall reading that contact reports on Allied shipping were often transmitted by wireless.

Zeps, of course, had no trouble carrying the large, heavy sets of the era.

I searched out your site after finding an Aircraft Interphone Set Box in my pile of radio stuff I've collected over the years.

You mentioned the BC-15 as the 1st spark gap morse transmitter designed for use in aircraft in 1918. The unit I'm examining right now was manufactured by Western Electric in 1918, its model number is SCR-57A Interphone Set, Type BC-10-A.

The only piece of information I was able to locate was this link
http://www.gordon.army.mil/ocos/Museum/Scr...ts/scrPart1.asp
which states that the SCR-57A was the First Aircraft Intercom (BC-10), for pilot and observer-gunner. Maybe this one is not a spark gap type but it is a morse code unit ??? or are all code units spark gaps, don't know...

Its a pretty interesting piece, the schematic shows the wiring harness to both the Pilot's and Gunners's leather helmets, each has a code key; the pilot has a second one on his "Steering Wheel", a regular round steering wheel.

Can you tell me anything else about the BC-10, what planes used etc. I already looked at the Spark Museum site but couldn't find anything.

I haven't taken any yet but if you're interested I can post some pictures.

Thanks
Bill

[retread]

Crosley,
Absolutely! Post photos of the Western Electric set if you are able. It would be greatly appreciated.
You say your set was for use with wheel controls. That would be "Depperdussin" control. Many of the JN-4's or "Jenny's" had this sort , particularly the earlier types. As these were widely used as trainers they mounted these in both foreward and aft cockpits and were known as "double-Dep" types.
Also, Curtiss often if not exclusively mounted twin yoke steering in his HS-1 flying boats. Although these were side to side as in a present day Cessna or Piper.

[retread]

Crosley,
As best as I can tell all spark-gap transmitters were strictly Morse (although all Morse trans. are not necessarily spark-gap). It wasn't until the development of vaccum tubes that voice transmission wireless was possible. Also the SCR prefix stood for "Signal Corp Radio", while "BC" was "Basic Component", so that your inter-phone set BC-10-A was made to be used with the SCR-57A radio set.

[William]

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