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Hella analogue motor tester and dwell angle meter

 

 

 

This Hella analogue motor tester was made in Germany,

and includes a Voltmeter, an Ohmmeter, an Ammeter,

an RPM meter, and a Dwell Angle meter.

 

The meter has no type number, and is merely referred to as

a "Hella Motor Tester".

 

If you drive a car that uses contact breaker points in the ignition

circuit, then the most useful aspect of this motor tester would be

the dwell angle meter, which gives an accurate and reliable reading

of dwell angle.

 

The dwell angle represents the time the ignition points are closed,

and the reading is given in degrees.

 

For most 4 cylinder engines, the dwell angle should be in the

vicinity of 50 to 60 degrees. 

 

For example, the dwell angle quoted for the 4 cylinder Mazda "MA"

engine used in the rear-wheel drive Mazda 626 (1979-1982), and

the Mazda 929, is from 49 to 55 degrees.

 

In practise, I have found that the "MA" engine will run reasonably

well on a dwell angle ranging from 45 degrees to 57 degrees (provided

the ignition timing is kept at around 8 degrees before top-dead-centre).

 

When installing a new set of points, I simply estimate the points gap

rather than using a feeler gauge, and if the dwell angle is somewhere

around 50 degrees, it's then a simple matter of setting the ignition

timing to the specified figure using a timing light.

 

If the dwell angle is around 65 degrees, it means the points gap is

not wide enough, and the gap needs to be increased.

 

A dwell angle of around 35 degrees means the gap is too wide, and

needs to be decreased.

 

 

 

 

 

 

Hella dwell angle meter for checking points gap[img]

 

                     

 

 

 

 

 

 

 

 

 

                        

 

 

 

 

 

 

 

 

Quote on John Barnes Blogsite

Picture of Kimberley aborigines taken by the Mjoberg expedition

 

 

 

 

The picture below was taken in the Kimberley region of

Western Australia during the Swedish expedition to the Kimberleys

led by Swedish explorer and ethographer Eric Mjoberg, in 1910

and 1911.

 

Mjoberg was responsible for the removal of human remains

from Aboriginal burial sites in the Kimberleys during that

expedition, and it wasn't until 2004 that the remains were

eventually returned to Australia.

 

 

 

Kimberley Aborigines photographed by the Mjoberg expedition in 1910-1911.

 

 

Photo of Kimberley aborigines taken during the Mjoberg expedition of 1910-1911.

 

 

 

 

 

 

 

 

 

 

Quote on John Barnes Blogsite

Philips car radio/cassette player, 1968 - world's first.

 

 

Philips radio cassette player advert, 1968.

 

According to this 1968 advert, Philips produced the

world's first car radio/cassette player.

 

The price in the UK was 38 gns - that's 38 pounds, 38 shillings.

 

 

 

 Philips 1968 radio/cassette player - world's first