For all of you spark fans

[AF9J]

A friend of mine sent me this link:

http://www.lakeerieba.com/HobartSparkXmtr/HobartSparkXmtr.htm

Basically, it's a recording made in 1938, of a spark transmitter in operation.  It's been put into an .mp3 file, so you can download it if you want to.  It's quite the trip.  There is vintage AM being done as a part of the spark transmitter test too, and even some old school CW.  The recording's only in so-so shape, but I did copy some of the spark transmission.  The transmitter hadn't been used in 17 years, and 2500V was going across the key during sending!!!  Yeow!!!

73,
Ellen - AF9J

[Steve - WB3HUZ]

Neat recording. I don't think I could listen to that spark note for long though. Very nasty and irritating to my ears. Kinda like fingernails on a chalkboard.

[AF9J]

Yeah and verily!  It's really hard to listen to.  Because of the audio of the note, it's hard at tiimes to separate it from the noise.

73,
Ellen - AF9J

[Ralph W3GL]

What you are hearing on that recording is not the "over the air" signal, just the buzzing of the spark its-self with the noise of the moter driving the rotary gap there in the shack!

The actual "radio signal" you would hear in a xtal receiver would be a varying buzz going up and down 30 or 40 cycles as the operator varied the foot driven rheostat.

Without that background noise it's not that hard to take, except that youse youngins ain't got the ears that we old crows had ...

Back in the day of spark, the ops listened to the buzz not a nice crisp "A above middle C" note and above! (440 cycles and up for the non-musical crowd...)

Oh yeah, there was still some spark on the Great Lakes in the late 30's early 40's...
Some of the non US carriers didn't go by the US rules and were somewhat slow
converting to the newfangled Vacuum tubes...