Since starting to work CW on-air a few months back I became familiar with the sound of other operators using Vibroplex Bug telegraph keys. I have been curious to try one of these semi-automatic keys even though I know that they are not recommended for new operators.
Vibroplex Original Semi-automatic Bug
The Bug uses a sprung pendulum to automatically send DITS. The action of moving the lever to the right starts the pendulum in motion and it creates evenly timed DITS automatically. DAHS are created by manual timing moving the key to the left. Using the key requires quite a bit more practice that using a straight key or paddles.
The Vibroplex semi-automatic Bug is considered a manual key by the SKCC (Straight Key Century Club) so it counts in SKCC contacts.
Used Bugs in decent working condition can often be had for under $70. This one was advertised as being "un-used new in box". Indeed, when I received it, it still had the shipping bumpers on the main spring and still had shipping grease. The glue on the nameplate had deteriorated and come loose and there was significant oxidation on the parts. This bug is a few decades old but that doesn't matter because Vibroplex bugs haven't changed much in design since 1907. The history of their creator, Horace Martin is interesting. He created the bug to help deal with his own degraded sending ability due to long hours operating a straight key as a renowned telegrapher.
Horace was a professional telegrapher so he designed the bug for professionals who sent at speeds well above what is normally used in amateur radio. The slowest speed this bug can send DITS without modification is about 25wpm and goes well above 40wpm.
As a beginning CW operator you will generally be well below that speed in your copy skills and likely your sending speed as well. But when experienced hams work you with a bug they will slow their DAHS down to your speed, however without special added weights there's not much they can do to slow down their DITS to your speed. This gives their FIST a unique sound. The DAHS are sent slowly but the DITS are zinging by. When you first hear this style your brain will not know how to interpret what you hear but give it some time and you will learn to copy them.
You can slow the Bug down by adding weight to the end of the pendulum. An inexpensive method is to wrap the weight with some solder. I've wrapped mine to bring it down to about 22wpm.
Wrap the pendulum weight with solder to slow it a bit
Here is a little video letting you hear a bit of the cadence of the bug. Now I just received this thing today and I practiced with it for about 30 minutes before making this video so I'm no bug operator for sure but it will give you some idea of the bug "swing"...
Here is a video running through the keys to see if learning a Vibroplex messes up my ability to use a paddle with an electronic keyer
The Vibroplex Bug next to a Kent Hand Key.
Manual Morse Code Keys
So don't "bug out" when you hear one of these on the air.