BACKGROUND INFORMATION
PERSONAL
I tell this story because others may relate to this ...
As a youngster growing up in NZ during the 1960's I had a strong interest in all things electronics. I am an "Old Timer" now and I am talking about the days when I would ride my bicycle to and from school and pass by this funny little electronics shop. The shop was called ELEQUIP (I can still clearly remember that but not much else these days!) and it was run by this European guy with a big pipe hanging from his mouth, I think he was a Czech it was a bit tough understanding him sometimes! He only had World War II surplus gear in his "Aladdin's Cave", shelves shelves and more shelves of what was to me, weird and wonderful equipment from the British Armed Services (I seem to remember). I spent many many hours in that shop, looking at all this strange Khaki coloured equipment, he even let me open them up to take a look around inside and he would explain what some of the parts were, I was drooling! - I was young and had no money to actually buy much of that stuff. The real fun was "out the back" of his shop where he put all the "junk" he didn't want, lots of modules, old valves, transformers - all freebies.
It was this type of experience that kindled in me the urge for the "treasure hunt" - looking at lots and lots of electronic equipment and sometimes finding something very special.
Looking and working through this UNAOHM EH-1000 bought all those early childhood days flooding back ...
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 board used extensive plug & socket interconnects to the other PCB's in the EH-1000, I have not cut any wires.
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.
Another aspect that surprised me a little is the extensive use of IC sockets for the active devices on most of the PCB's, a potential source of trouble when it comes to reliability but great when the board is being used as a component farm - no fuss de-soldering useful components.
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 get down to the PCB module I am offering ...
POWER SUPPLY PCB MODULE
PCB type: double sided
Part #9180
The PCB has absolutely no other markings or coding on either the component side or underside.
Professionally made board using a fibreglass substrate but it looks to have been meticulously manually soldered. In fact the entire construction of the EH-1000 looks as though this equipment was manually constructed from start to finish - no automation.
This board takes care of ALL the DC voltages required by the EH-1000, including the high voltages for the CRT. This board can be used as a "drop in" replacement in another EH-1000 but you still need to connect the external devices such as the 6x TO220 regulators and the high voltage transistors which are mounted "off board" - I am ONLY offering the main PCB here, not those external components.
I really think that the primary usefulness of this board would be the components that could be "farmed" from it ...
The Yellow jacket capacitors are FRAKO's from Germany, most are low voltage (up to 40V) but one is 100uF 160V
High Voltage lead (Red) with Anode cap for the CRT (advertised separately) - this comes from a epoxy filled block which has no markings on it - the epoxy is clear so I can see a number of capacitors inside the block. Next door is the EHT transformer, this is marked only as N27 which I seem to remember is a reference to the ferrite core material, not the component part number.
Almost all of the PCB modules use sockets for the integrated circuits, this board has just one device fitted and it is a Motorola MC14052 (4 Channel multiplexor/demultiplexor)
The larger transistors are all NSD series (National Semiconductor) in TO202 package e.g NSD459's
Remaining passive components are generally the likes of ITT or WIMA's (box package) along with a couple of nice looking high power resistors but I cannot read off the manufacturer (on the underside)
To me, not a very exciting board but it really depends what you are looking for in a component or of course, just use it as a drop-in into another EH-1000
Numerous (15, yes 15 of them!) board mounted male connectors (most Nickel plated but a couple are Gold plated) for connection of the AC input(s), low power voltage regulators etc
This PCB was FULLY FUNCTIONAL prior to removal from the equipment
PCB DIMENSIONS:
220mm x 87mm
WEIGHT (quite heavy): 300g
This 9180 PCB has now been "laid to rest" within bubble-wrap and is lying on a stiff cardboard backing, everything then within a sealed clear plastic packaging.
