|  | SOURCES: Photos from internet auctions, inspecting lots of 
				units in flea markets. THIS LIST MAY NOT BE COMPLETE (and probably isn't). It probably is not 100% correct too. Because there were many calculators, some made using currently available parts, not ones designed in schematics, it may not be OK for all units. If you have an unit with different guts, it's normal. A WORD ABOUT POWER: Elwro calculators were manufactured in quite unstable market conditions, so many times only available components were used. This applies to power connector too, so you can find these 4 types of power: - Cable going from a hole near bottom edge of rear cover. Hole for socket covered by piece of plastic/laminate. - Cable going from a hole in a special plastic cover covering power socket hole in rear cover. - Typical 2-pin "Radio type" socket. - Typical 3-pin socket, as seen in computers (early 105LN). And all these calculators need 220-230V AC, 50Hz. | 
		
		WHAT IS NOT COVERED (only listed as existing models): 
		- Pocket calculators: 
		- 440 (Bolek with poor manufacturing process, early units not labelled 
		Bolek but "Elwro 440"), 
		- 441 Bolek (simple model), 
		- 442LC Jacek (The only Polish LCD!, black or silver metal housing), 
		- 480 Lolek (scientific model), 
		- 481 Lolek (scientific, better manufacturing process), 
		- 482. (???) 
		- Printing calculators: 
		- 230, (???Soviet Elka clone???) 
		- 240, 
		- 242, 
		- 255L, 
		- 255N,  (2xx were printing models)
		- 330, 
		- 343 
		- Eltra K-741, Unitra Brda series, etc. It's NOT Elwro. 
		- Magda - LCD pocket calculator made in small quantities on Japanese 
		parts, probably recovered from licensing material.
		In general, the 3-digit type designation was used to inform about 
		calculator capabilities (source):
 - Digit 1:
   - 1 - Tabletop calculator
   - 2 - Tabletop calculator with printer
   - 3 - Tabletop calculator with printer and display
   - 4 - Portable calculator
 - Digit 2:
   - 0 - basic 4-operations
   - 1 - 4 operations with  percent and K-constant
   - 2 - As above with 10^8 overflow?
   - 3 - As above, with 1/X, X and X^2.
   - 4 - As above with one-number memory
   - 5 - As 3 and two-number memory
   - 8 - Engineering
   - 9 - Programmable  
 - Digit 3: Version, usually it means that the same functionality has been 
		achieved with different components. Additional PCB revisions were marked 
		on PCB with letters like "Elwro 143A".
| TYPICAL COMPONENTS or how the calculators are described: - Power supply unit - supplies all needed voltages to run both logic part as well as display, which in some cases requires special voltages. - Chipset - set of chips (or single chip) used to perform logical calculator functions. - Display - A device to show numbers. - Display driver - A device to transform results from chipset to display-compatible signals. - Keyboard - A set of keys to control the calculator. Usually aligned in multiplexed grid. - Keyboard driver - usually built-in chipset, circuit to transform pressed keys to commands for chipset. In Elwro desktop calculators, chipset may be single-chip or (usually in some scientific or financial calculators) composed of multiple chips, with keyboard driver built-in. Power supply unit is usually the same transformer-based one supplying two voltages: For logic and for VFD display tube which requires a bit higher voltage to operate. Also a AC filament for tube is supplied by mains transformer. Display driver may be realised on transistors, integrated circuits or hybrid circuits. |  | 
		Quick jump:
		Simple:  105L  105LN 
		EW-115  EW-116 
		120L  130 
		131  140  
		142  141  143 
		144  151 
		Scientific:  180  181 
		182  183  
		184      Programmable: 190
 
		
		 ELWRO 105L
  ELWRO 105L  
		The first calculator made by Elwro using Busicom's technology, maybe a 
		license (as in 1970s Poland bought many licenses from western 
		countries). Built around Japanese parts, Mostek MK6010 chip, with 
		transistor-resistor circuits to drive 12 Futaba VFD tubes. Remember 
		these circuits, in later models Elwro used hybrid circuits (Japanese 
		first, Polish and soviet later), later switching back to transistor-resistor 
		because lack of components (Telpod manufacturing hybrids was doing 
		something more important). Elwro 105L has an unusually long shape and 
		it's its first known Elwro calculator based on Japanese project. This 
		shape is taken from earlier Busicom model, which used logic chips, 
		not calculator-in-a-chip circuit. L here could mean "Licensed".
		Power supply: Transformer-based
		Chipset: Mostek M6010
		Display driver: Transistor-based (see 
		photo here)
		Display: 12 VFD Tubes, probably Futaba 1001 / DG1001
		Keyboard: Spring buttons with sliding decimal place switch 
		Source: 
		
		http://gallery.olek.waw.pl/inne_zdjecia/stara_technika/ELWRO_105L.jpg.html 
		
		
		 ELWRO 105LN
 ELWRO 105LN  
		This is a very popular unit, first really mass manufactured. Simplified 
		version of Busicom 120DN, used 12 Futaba VFDs too. In some units VFDs 
		are driven with hybrid circuits made in Poland (GC-003), some use "black 
		boxes" (JRC IC-3552). 
		I have no idea who exactly made these circuits, as they were probably 
		manufactured in Telpod workshops only. From former Telpod employees I 
		got two names of hybrid circuits designer centres: OBREM (for analytical 
		devices, no idea about acronym) and OBRMHiR (Ośrodek Badawczo-Rozwojowy 
		Mikroelektroniki Hybrydowej i Rezystorów - Development-research centre 
		of hybrid microelectronics and resistors - 
		
		their web page archived).
		
| It has a wheel rotary switch for setting decimal places mode. Switches 
		are purely mechanical. Elwro simplified this model very much to 
		manufacture is as cheaply as possible. PCB was used as in Japanese 
		models, but most connectors can be seen only in earliest models, in 
		later units they're gone - wires are just soldered to pads. Yes, edge 
		connector of keyboard too. In later models they drilled holes in PCB, so 
		it looked more professional, but in 105LN wires are just soldered to 
		edge connector pads and they stick from behind the board. Power supply: Transformer-based, "canned" one. Chipset: Mostek MK6010 Display driver: Hybrid chips, Japanese or Polish Display: 12 VFD tubes, Futaba DG10 Keyboard: Spring buttons with rotary decimal place switch Source: e.g. my units |  | 
		
		
		 ELWRO EW-115
 ELWRO EW-115  
		Used Soviet VFD tube, because import from western countries was very 
		difficult. It was Soviet IW-18, VFD tube designed for calculators: 8 
		digits and minus. It needed some construction changes, mostly re-wiring. 
		In the left, manufacturer's logo instead of rotary decimal 
		places switch. Probably in some units they used Soviet ICs. 
		Power supply: Transformer-based, "canned" one.
		Chipset: ??
		Display driver: ??
		Display:  ??
		Keyboard:  Like Elwro 105LN but without rotary switch 
		
		Source: Mentioned in
		
		Mera bulletin from 1977, page 40
		
		
		 ELWRO EW-116 (Elwro 116)
 ELWRO EW-116 (Elwro 116)  
		Two major changes: One: it's made using better process, Second: some 
		units are not using IW-18 but 8 or 9 separate IW-6 VFD tubes. IW-6 tubes 
		are LIKE Futaba tubes... LIKE, doesn't mean the same. They're few 
		milimeters bigger horizontally. These tubes will be used in some later 
		models. 
		Power supply: Transformer-based
		Chipset: ??
		Display driver: ??
		Display: 9 VFD tubes (one for sign)?  
		Keyboard: Like Elwro 105LN but without rotary switch  
		Source: Mentioned in
		
		Mera bulletin from 1977, page 40,
		
		collection item,
		
		Another Mera bulletin with photos (page 35).
		
		
		 ELWRO 120L
 ELWRO 120L 
		Like Elwro 116. Probably contained some metal stand to make it more 
		comfortable, but it was not the primary difference. Some models used an
		exotic MCX74204 circuit which was manufactured in very small quantities
		by Polish CEMI, probably from pre-made stuctures (MCX is a designation of
		raw structure) packed to ceramic DIP40 housing.
		According to Mera bulletin, model 120 was made using only components 
		from Poland and Eastern Block countries.
		Power supply: Transformer-based, "canned" one
		Chipset: CEMI MCX74204 (source)
		Display driver: ??
		Display: ??  
		Keyboard: Like 105LN  
		Source:
		
		Alek's site ,
		
		Auction archive,
		
		Mera bulletin with photos (page 35)
		
		
		 ELWRO 130
 ELWRO 130
		Used a foreign VFD tubes and HD36290 chip popular in Canon pocket 
		calculators.
		Power supply: Transformer-based
		Chipset: HD36290
		Display driver: Built-in chipset
		Display:  Futaba 9BT02 - small rectangular 9-place VFD tube.
		Keyboard: ??  
		Source: Schematic in
		
		
		Leon Instruments site (?article
		
		saved but no schematic?).
		
		
		 
|  ELWRO 131 Better keyboard. Well, today it's not better, membrane keyboard has smaller and more comfortable keys but today distance foam falls apart between contacts. It's possible to clean this foam away, it will work but will make multiple clicks. And more functions: Simple memory, "finance mode" with 2 decimal places, 1/x, 00 and % keys. Using a 12-place tube with Memory/Error/Minus signs. which in current chipset are not used. Power supply: Transformer-based, PCB-soldered or fastened one Chipset: Soviet K145IK508, K145IK1802. Display driver: Soviet K161KN1A Display: Soviet 12-digit VFD tube IWL1-8/13 - 12 digits + -/M/E. Keyboard: Membrane, black-white-orange with rocker power switch and sliding decimal places switch. Source: e.g. my unit |  | 
		
		 ELWRO 140
 ELWRO 140  
		No "finance mode", but squares, square roots and finally full-featured 
		memory as seen in today's calculators, with M+, M-, X->M, MC, MR keys. 
		Because keyboard was too small some keys had to be "shifted". Display: 
		IW-18. Chip: MPS7545-004. 
		Power supply: Transformer-based, fastened to board
		Chipset: MOS Technology MPS7545-004
		Display driver: built-in chipset
		Display:  Futaba 9BT-02 - 9-place rectangular VFD tube, 
		smaller than window.
		Keyboard: Membrane, black-gray, power switch is slider while in a 
		bottom there is a "1" quality sign  
		Source: e.g.
		this movie , 
		Schematic in
		
		
		Leon Instruments site (?article
		
		saved but no schematic?).
		
		
		
		 ELWRO 141
 ELWRO 141  
		See Elwro 140. The only difference is with displaying tubes: They're 9 
		?IW-6? Soviet VFD tubes. 
		Power supply: Transformer-based
		Chipset: MOS/LSI MPS7545-004
		Display driver:  ?transistor-based?
		Display: 9x VFD tubes  
		Keyboard: Membrane , blue-black or grey-black keys, sliding power 
		switch.
		Source:  Schematic in
		
		
		Leon Instruments site (?article
		
		saved but no schematic?).
		
		This advertisement,
		
		collection page
		 
		
		 ELWRO 142
 ELWRO 142  
		From outside very similar to model 140. Exact differences not known. 
		Power supply: Transformer-based
		Chipset: ??
		Display driver: ??
		Display: 9 VFD tubes  
		Keyboard:  membrane, blue-black
		Source: 
		This page 
		 
|  ELWRO 143 and all its sub-models Built with Eastern components, CEMI circuit and Zatra transformer, number is displayed on 8 IW6 Soviet VFD tubes + 1 tube for minus and memory indicator. Known A and B models with slightly modified power supply. There's also 143K PCB revision, some photos show it with IW-18 tube, while other with 9 IW-6 tubes. Usually black case with blue keys. Rarely used 3-pin power connnector instead of typical in these machines 2-pin "radio" type. Power supply: Transformer-based, fastened to PCB Chipset: CEMI MC74007 Display driver: Transistor based Display: 9 VFD tubes, IW-6. Keyboard: Membrane, blue-black-orange keys, sliding power switch Source: e.g. my unit |  | 
		
		 ELWRO 144
 ELWRO 144  
		The most popular calculator manufactured since early 1980s till early 
		1990s. All experiences from developing earlier models resulted 
		in 144 model, which used IW18 tube, MC14007 and transistor-resistor 
		drivers. Only typical operations could be performed: +, -, *, /, %, sqrt, +/-, decimal point setting and memory operations.  
		This calculator had 3 models, but differences were small: track sizes 
		and power supply simplification (PCB-mounted mains transformer). Units 
		from 1990s are very poor quality, made of paper-based laminate and too 
		small quantities of soldering alloy. 
		
| Power supply: Transformer-based, soldered 
				to PCB (fastened in early units) Chipset: CEMI MC14007 (formerly MC74007 according to datasheet) Display driver: transistors Display: IW-18 VFD tube Keyboard: membrane, white-black-orange, black-red, blue-black-orange, different variations of power switches (mostly sliders), white and brown cases, sometimes with model printed on the top. Source: e.g. my units, 
 |  | 
		
		 ELWRO 151
 ELWRO 151  
		The last upgrade of Elwro's simple calculators. Casing is as in 144, but 
		keyboard has been revamped, keys are longer in width, like in 183 
		series. 12-digits and minus in one VFD tube, capabilities similar to 
		144 but probably two-number memory. 
		Power supply: Transformer-based
		Chipset: ??
		Display driver:  ??
		Display:  12-digit VFD tube with minus sign / M / E. 
		Probably like in Elwro 131.
		Keyboard:  Membrane, black-white-orange, longer keys, two 
		sliding switches (?memory?)
		Source: 
		Legendy PRL site, 
		 
|  ELWRO 180 Scientific calculator with enhanced functions, 12-digit VFD and DEG/RAD support (by mechanical switch). All features of 144 plus: Pi, sin, cos, tan and their inversions, e^x, ln, log, degree to radian and back, y^x. Power supply: Transformer-based Chipset: ?? Display driver: ?? Display: 12-digit VFD tube. Keyboard: membrane, black-blue-orange with sliding switches Source: collection page, this movie, photo | 
		
		 
|  ELWRO 181 Small keyboard layout change. Still built with western components, as there were no components for these scientific calculators in eastern block countries. Built around uPD953C chip and single 9-digit VFD with 8 active digits (one for minus and memory). Power supply: Transformer-based, fastened to PCB Chipset: Nec uPD953C Display driver: Built-in chipset Display: 9-digit rectangular VFD, smaller than calculator's window. Keyboard: Membrane, black-blue-orange, sliding switches. Source: e.g. my unit, 
 |  | 
		
		 
|  ELWRO 182 Making 181 with Eastern components? Let's use old good IW-18 to display, but K145IK1301 soviet chip. Some functions were added, support for bracketed computation, simple DET function - delta of polynomial, coefficients are "("-separated?. And different memory handling - using STO/X->M/MR/M+/CM keys only. Soviet chipset required external clock generator, here implemented on K165GF3 chip. Power supply: Transformer-based, fastened to PCB Chipset: K145IK1301, K165GF3 as clock generator Display driver: transistor-based Display: IW-18 VFD tube Keyboard: membrane, black-orange keys. Power switch and function sliders. Functions painted on and above keys. Source: e.g. my unit, collection page |  | 
		
		 ELWRO 183
 ELWRO 183  
		Used different casing, the same as MIK-1 CA80 teaching computer. 
		Manufactured in small quantities in late 80s/early 90s. 
		Power supply: Transformer-based
		Chipset: ??
		Display driver: ??
		Display:  12-digit rectangular VFD tube,
		Keyboard:  Membrane, long keys in new casing, 
		white-red-orange.
		Source:
		
		Retroplayer site,
		
		
		Photos on Leon Instruments site (mirror)
		
		
		
		 ELWRO 184
 ELWRO 184  
		Changes not known. Existed. 
		Power supply: Transformer-based
		Chipset: K145NK1301 (source)
		Display driver: ??
		Display: ??  
		Keyboard: As in Elwro 183  
		Source:
		
		Archive auction,
		
		another one, 
		small 
		photo, 
		
		
		
		 ELWRO 190
 ELWRO 190  
		Programmable calculator built in very small quantities in late 1990, but 
		design was much, much older. Made of Polish chips (chips made to order 
		too) only. Today it's very rare. Programmable using 10-variables programming 
		chip with jumps and IF instructions.
		Power supply: Transformer-based
		Chipset: CEMI MC14009, MC14010, MC14011
		Display driver: ??
		Display:  12-digit VFD
		Keyboard: Membrane with long keys, white-red-orange-black 
		(instruction keys are black).
		Source: 
		Legendy PRL Page,
		
		
		Leon Instruments reconstruction (mirror),