Basic Etching

Today I will explain about the process of manually creating a printed circuit board (PCB) from scratch. The process start with an initial design of the circuit and then reverse drawing the circuit into a piece of copper plate with a permanent marker. Before drawing on the copper plate, the plate is cleaned with an extra fine sand paper until the plate is shining. This process is to eliminate the oxidized layer from the copper plate.

Finished circuit drawed on the board

After drawing the circuit on the board, and the ink is let dry, the etching process is implemented. What is etching? Etching is the process of creating an image on metal or other surfaces by means of an acid. Remember to wear gloves when doing this process as it involves highly acidic materials.

Chemical used as the acid

Etching process 1

Etching process 2

While the board is inside the acidic liquid, the tray is to be shake constantly to remove the unwanted layer of copper until the circuit design can be seen clearly. After etching process, the circuit connection lines which are covered with the permanent marker can be observed clearly. The board should be dry completely and then remove the permanent marker layer and the copper connections in the circuit can then be seen.

Before Etching

After Etching

After removing the permanent marker

The end result is shining connections of copper on the board which we called as printed circuit board or PCB. After this the board can be drilled with holes so that components can be placed on it and be soldered.


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Minolta 110 Zoom SLR

The Minolta 110 Zoom SLR was a 110 single lense reflect(SLR)camera produced by Minolta of Japan between 1976 and 1979. It was the first SLR in 110 format. This type of camera has builtin 1:4,5/25-50mm Zoom-Lensa zoom lens which mean it has a focal length between 25mm to 50mm. It uses porro-mirror instead of pentaprism. The camera shutter and appature appear to work without film loaded and the viewfinder displays an indicator when the shutter release is pressed. It also has macro focusing down to 11 in (280 mm). This gave a field of view range approximately equivalent to a 50–100 mm zoom lens on a 35 mm format camera. Unfortunately, there was no built-in flash, but a hot shoe on the top allowed an external flash to be attached.

Minolta 110 Zoom SLR

Bottom view

Back view

Top View

Film insertion

Front View

Camera Info and History.
First introduced in September, 1976.
Camera type : 110 cartridge porro-mirror SLR camera with zoom lens
Picture size : 13 x 17mm
Lens : Zoom-Rokkor f5/25-50mm
Light metering : external metering system, aperture-priority automatic exposure
Shutter : horizontal-run focal-plane shutter with metal curtain Shutter speeds : B, 10-11/1000sec.
Body dimensions : 53.5 x 108 x 132 mm, 430 g
Body weight : approx. 430g.

The manual of this camera can be obtained at here.

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