Teco TE8053 TE 8053

		Home New Stuff Author Links Guest book Web-log	Adverts Bric-a-brac Calculators Components Ephemera Events	For Sale Glossary History Hit or Miss Radios Transport	Ultra Valves Wanted Metal Puzzles Clocks

Calculators: Handheld: Teco TE8053 (aka TE 8053)


		Size (approx):	82mm x 150mm x 34mm (w x h x d) Weight 220g excluding batteries.
		Power:	6.0V DC using 4 x AA size batteries (0.7W). It does not accept an adapter. There is a yellow ribbon in the battery compartment to aid battery removal. A note on the back states "In case of low or poor battery performance display will show all 8's".
		Case:	Two piece case in brown and off-white chunky plastic. The purple plastic display filter is slightly inset in a prominently raised section. It has white printed brand and model number with a additional border and negative indicator. The keyboard surround is flush in its raised section and made of black patterned plastic. The switches sit in a further raised section with a white printed black sticker for the labels. The keys are long-travel with a hollow clunky sound.
		Display:	8 digit red LED with a discrete LED for negative indication
		Features:	Standard four functions, semi RPN (arithmetic) logic, fixed digit switch.
		Age:	1973
		Manufacturer:	No manufacturing details or serial number, but it is made in Taiwan.
		Comments:	Chunky early single-chip calculator with rather basic zero or two digit capability. However, with out an adaptor option it must have consumed batteries rapidly. The original cover is soft black plastic with a side-bottom-side zip. It has an internal strap to hold the calculator in place which sits between the display and keyboard. My example is not working.

Components:	1 x cpu; Mostek MK5010P, C747 7311 KDQ (week 11 of 1973), 40 pin DIL, 0.6" width white ceramic 8 x 1 digit LED unit (with separate linear magnifying lens) 1 x discrete red LED 22 x transistors 11 x diode 12 x capacitors 49 x resistors 1 x transformer: Paktransformer AA 1020
Boards:	The main cpu board is fixed face-up over the keyboard assembly (Sanyu SYA-12057 48.4.18) (this is date code 18 April 1973) with four screws. The display board (CC02D038 KUOTIANG-2) is held in place by another two screws,
Construction:	Remove the single screw (the one at the top is not used) from the back and this section comes away easily - hinge to the right so that you do not break the power wires.

Logic comments:	The (C) key is used to once cancel an entry whilst a second press clears the whole calculator
	The logic is semi RPN (Reverse Polish Notation), i.e. arithmetic. To do 4-3 key in (4)(+=)(3)(-=).
	Negative numbers are shown with a single red LED the far left of the number thereby allowing full eight digit negative numbers.
	Overflow shows "888.8.8.8.8.8."

	This image shows the rear of the case removed. Sturdy construction with screws and metal brackets along with the large component count give its age away. The top board houses the display and sits upon a large metal plate with a linear plastic magnifying lens. The coloured wires that connect the keyboard assembly to the main board run about half the length of the calculator allowing you to easily separate the main board for servicing.
		The image above shows a closer view of the individual seven segment LED displays and the discrete single LED to the left.