BACKGROUND INFORMATION
THE EH-1000
After years of use and then storage once the analog Teletext television system was turned off yonks ago, I have finally gotten around to placing this professional, very well built equipment onto the workshop bench ... the "operation" has begun
This equipment was fully functioning but of no possible further use in our digital television (with no teletext broadcasts) era so now I have extracted components and modules "of interest" which can be used to restore another EH-1000 or think of this board as a "component farm" a place where some difficult (or impossible) spare parts may lurk ...
This PCB board module houses just one major item, a very nice Cherry (Germany) 3 gang push button switch with BCD encoded outputs. Wait, it gets better ... this switch is socket mounted so it is easy to remove and use in other equipment!
Now it's time to take out the "scalpel" and start the op!
One of the first things to note is that although this is branded Unaohm and manufactured in Italy, the components inside have been substantially sourced from European and English component manufacturers, the likes of Siemens and Philips in particular. This ELMA switch is readily identifiable, the company being well known in the electronics industry for their very high quality products, no sub-standard Asian product in the EH-1000!
THE DONOR EQUIPMENT
UNAOHM - Teletext Video RF Analyser
Model: EH-1000
Designed & manufactured in Milano, ITALY
Circa late 1980's (based on advertisements placed in Wireless World at the time and the date stamp on the AC transformer core)
Technology: Analog video broadcast signal analysis - specifically for examining lines of Teletext information "riding along" with the video signal
Luggable (heavy at 15kg) due to the heavy duty Aluminium outer case but more importantly, the inside welded steel frame chassis inside.
Well engineered inside, logically laid out using a number of modules which are well interconnected.
Designed for 220V 50Hz operation (because of this, we used this equipment via an AC variac many years ago)
Green emitting rectangular CRT based front panel display
Interested in the technical nitty gritty? Here is an old copy of the spec sheet
Enough of the yacker, let's "go out into the fields" and see what fruit this "component farm" could provide ...
CHERRY (Germany) - Front Panel 3 Gang Switch Module
EH-1000 original purpose was the Television Line Selector (central area of the front panel)
PCB type: single sided
Part #9176 (PCB) Switch # is unknown, stamped into the side is simply CHERRY
One small board with just one major solitary component, the CHERRY 3 gang push button ten position switch, one button for UP and the other for DOWN
Each gang operates independently of any other
BCD output encoding (5 pins) meaning that every switch contact is available at the rear, 15 pins in total
Fully sealed switch unit(s)
The switch is inserted into a tight fitting socket, good strong "legs" and easy to remove from this socket.
The legs look to be Nickel plated
Please keep in mind that the EH-1000 (and thus this board & switch) has been and was FULLY OPERATIONAL - you can be confident this switch will perform as designed.
Not interested in fitting into another EH-1000? Many high quality European designed and manufactured pieces of equipment use these CHERRY range of switches, this could be just what is needed for your own service or restoration task.
PCB DIMENSIONS:
30mm x 30mm
SWITCH DIMENSIONS:
29mm wide x 24mm height x 26.25mm depth
These switch dimensions include the front flange (for a flush fitting to the panel)
The switch is secured to the panel with the two sided "snap fit" tabs
WEIGHT: 60g
COSMETIC CONDITION:
USED
CLEAN
NO damage to the PCB or switch body at all
NO wear showing to the front digit displays (behind a small clear perspex cover anyway)
All gangs have a smooth switching action, using both the UP or DOWN buttons
This 9176 module is now nice and safe within sealed bubblewrap, waiting to come to the rescue of another piece of equipment.
