the bug in my shack

I started my CW activity using a vertical key; after one year I was curious to use an orizontal one but it was hard to home-brew using only a drill; so, waiting for the bug, I built a jambic keyer.
But a day I found on a old magazine an interesting project........BINGO! So, if you are looking for a simple but functional bug, read this page: I built it with all I found on my cellar!
You need only:
- Threaded bar 8mm diameter;
- Nuts and washers 8mm diameter (7);
- Nuts and washers 3 mm diameter (10-15);
- Double face copper board (or single face) 10 x 10 cm;
- A brass spacer (or copper board);
- Two brass nuts (or relays contactes);
- Some spring;
- A "C" channel 8x4x11 cm (iron, alluminum or other);
- Two of those parts used to cover computer slots, in the back of the PC;

Will it really work? Sure! I buit it waiting to buy a bug, but now I don't want buy it any more!

Well, the "C" channel is the base (See Picture 1).

I used for paddles two of those parts that are back to PC to cover free slots, but you can also use copper board or similar (120x20x 8 mm); at the end of both paddles I made an 8mm hole; trough this passes the 8mm threaded bar which is locked on the "C" channel.
At the end of each paddle there is an insulated covering (you can use wood or plexiglass) (See Picture 2).

Contactes are made in the same way (See Picture 3); to "fine tunung" the bug I used simple screw bolt (one for each side of the "C" channel) as shown in the picture.
In this way I can vary the space between paddles using the screw bolt on the 8mm threaded bar (to do once for all, 12mm mine) and the space between contactes with the two screw bolt on the sides of the "C" channel (you can vary it everytime you want).

download l'articolo completo sul keyer jambic

Download Article: a Jambic Keyer

The base and the keyer printed board take place in a metallic box within a 9V battery; on the front panel there are paddles and speed knob (See Picture 4); on the rear panel there are 3 jack: Tx, Vertical key and PC (interface for contest logging software like CT ecc.) (See Picture 5).

I spent no more than 1$ for the bug (just some nuts and washers).

Below there are some articles about bugs founded on Radio Rivista;


- Due tasti telegrafici R.R. 7/97 pg 25
- Aspettando il bencher R.R. 10/97 pg 22
- Tasto elettronico orizzontale R.R. 8/94 pg 23
- Provato per voi ,amanti del cw R.R.10/93 pg 39
- Dopo la copia...l'originale R.R. 8/93 pg 27
- A proposito di paddle R.R.4/92 pg 23
- Semplice paddle per tasti elettronici R.R.12/91 pg 30


- Bug elettronico R.R.2/97 pg 25
- Memoria per tasto verticale R.R. 6/97 pg 20
- Un economico keyer jambic R.R. 7/96 pg 19
- Semplice manipolatore elettronico R.R. 12/96 pg 25
- C mos keyer II motorola R.R.4/93 pg 40
- Electronic keyer R.R.2/92 pg 21
- C mos keyer curtis 8844b R.R.8/90 pg 21 *
- Manipolatore elettronico R.R.9/89 pg 42
-keyer qrp R.R 12/78 pag. 1227 *
-il bug di VIU R.R. 3/82 pag. 283*
-C Mos keyer R.R. 1/82 pag 52
-Tasto elettronico della terza generazione R.R. 4/97 pag. 37
- C mos super keyer R.R. 5/96 pag 78

* = both mechanical and electrical description.

You can add:
- Side-tone circuit;
- relay for old Tube TX;

73 de iz7ath, Talino