BBC Microcomputer - How Many?
Total production of all varaints of the BBC Microcomputer is usually quoted as 1.5 million. The total on this page is based on analysis of serial numbers gathered from various sources, including the StarDot forums, personal websites and photos on eBay. I am still collecting data so all estimates on this page could change, however as of 15th March 2023:
This total is based on the serial numbers of 1,844 computers. That’s 0.19% of the estimated total and a 57% margin of error compared with the 1.5 million total.
The difference could be explained in a number of ways. It is possible that whole ranges of serial numbers are not represented in our data (our total for Export-specification machines is far lower than the 50,000 machines Acorn is said to have ordered). Perhaps a large number of machines produced under licence by other manufacturers are not included. For example, the data contains a handful of serial numbers belonging to computers built by SCL in India but Acorn also reputedly licensed production in other countries too. Another possibility is that the 1.5 million total includes the 32-bit ARM-based machines which were also badged as a BBC Microcomputer.
The total can be broken down by variant, to show the relative production numbers of Model A/B, Export, B+/B+ 128K, Master Series and Master Compact.
BBC Microcomputer Production by Variant
Variant | Number Produced | Percentage of Total |
---|---|---|
Model A/B | 584,500 | 61% |
Master Series | 259,500 | 27% |
Master Compact | 55,000 | 6% |
Model B+/B+ 128K | 35,500 | 4% |
Model B (Export) | 13,000 | 1% |
Model B Clone | 8,500 | >1% |
956,000 | ||
Represented visually, the proportions of each model are easier to see:
- Model A/B
- Master Series
- Master Compact
- Model B+/B+ 128K
- Model B Clone
- Model B (Export)
Model A/B Production
Let’s look at Model A/B production in more detail. This excludes the B+/B+ 128K and Master variants. The graph below shows approximate monthly output from each manufacturer, along with the current PCB issue(s) at the time. Models A and B are grouped together because although each model has its own product code — ANA for Model A and ANB for Model B — the product code was not included in the serial number for the first 18 months of production. This makes it difficult to make estimates of how many of each type were produced each month.
- Cleartone
- ICL
- AB Electronic Systems
- Race
- ‘06’
- Keltek
- ‘09’
- Wong’s Electronics
- AB Electronic Systems (07)
- ‘ANB100’
Note that there is a significant overlap between the beginning of Issue 7 production (June 1983) and the end of Issue 4 production (May 1984). This is because the Issue 7 board was adopted at different times by each manufacturer and Keltek built Issue 4 machines for some time after the other manufacturers had switched over to Issue 7. Why Keltek would have been using Issue 4 PCBs is unclear; perhaps Issue 4 boards continued to be produced alongside the Issue 7 versions — or perhaps the entire remaining stock of Issue 4 boards was assigned to the company to last for the entire production run.
Production volumes have been estimated by using date labels on PCBs where they are available. Not all manufacturers affixed date stickers so for those, the production is estimated based on volumes reported in contemporary magazine articles.
Model A/B Production By Model
The same PCB is used in both the Model A and Model B. Model B PCBs have more components fitted, whilst the Model A variants have empty sockets or spaces ready to accept the components necessary up upgrade them to Model B specification.
So how was production split between Model A and Model B? The fact that the product code was not included in early serial numbers makes it difficult to be precise. For example, none of ICL’s serial numbers included a product code, but all machines from serial number 005000 had the entire 32K of RAM soldered to the PCB, so we can be certain that they were all Model Bs. ICL machines with lower serial numbers could have been built as Model A or B and there is not enough information available to estimate the proportions. On the other hand, Cleartone is simple: all machines they produced were Model A specification, except for a very small number of Issue 1s — only some of which were Model B.
BBC Microcomputer Model A/B Production
Model | Number Produced | Percentage of Total |
---|---|---|
Unknown | 30,275 | 5% |
Model A | 22,875 | 4% |
Model B | 529,850 | 91% |
583,000 | ||
Acorn expected the Model A to be the more popular of the two and planned production on a 2:1 ratio (Model A:Model B). This projection was quickly proved wrong and the Model B eventually outsold the lower-specified model by a considerable margin.
The eventual Model A:Model B ratio was closer to 1:20. Of the relatively small number of Model As originally manufactured, very few remain in their unmodified state.
Model A/B Production By Issue
The issue number of a Model A/B machine is determined by its main PCB. Five numbered issues were manufactured: 1, 2, 3, 4 and 7. Issues 5 and 6 were drawn up but not put into production. Machines based on Issue 1 boards were not sold to customers.
So how many of each issue were produced?
BBC Microcomputer Model A/B Issues
Issue | Number Produced | Percentage of Total |
---|---|---|
Issue 1 | 275 | >0.1% |
Issue 2 | 4,725 | >1% |
Issue 3 | 57,500 | 10% |
Issue 4 | 118,000 | 20% |
Issue 7 | 402,500 | 69% |
583,000 | ||
Each issue was produced in greater quantities than all the issues preceding it combined. This makes the latest issue — Issue 7 — by far the most common.
The Issue 1 sector of the pie chart is so small as to be almost invisible, but if you zoom in on the graph you will see it. 90% of all Model A/B machines are Issue 4 or later. 99% of all Model A/B machines are Issue 3 or later.
Serial Number Ranges
The production figures for each model can be broken down by serial number range. This gives an indication of how many machines were produced by each manufacturer which Acorn subcontracted to build them.
The tables below show the lowest and highest known serial numbers in each range. The count column shows how many examples of serial numbers in that range are known. This is followed by the highest and lowest known serial numbers — your computer might be listed here. The range column shows the difference between those two extremes, giving the minimum possible production. The est. total column shows the estimated total for that range, based on the difference between the lowest possible serial number and the highest known serial number rounded up to the nearest 500 (but see the footnote on AB Electronics serial numbers for details of an exception to this).
Model A/B - Total Produced: 584,500
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
ICL Model A/B | 142 | 000078 | 029779 | 000078 029779 | 29,702 | 30,000 | 30,000 (29,702) |
Cleartone Model A/B | 54 | 100004 | 110778 | 100004 110778 | 10,775 | 12,000 | 12,000 (10,775) |
AB Model A/B* | 269 | 112359 | 205756 | 112359 205756 | 93,398 | 88,000 | 88,000 (93,398) |
AB Model B | 194 | 01-ANB01-3000252 | 01-ANB01-3092181 | 01-ANB01-3000252 01-ANB01-3092181 | 91,930 | 92,500 | 92,500 (91,930) |
AB Model B (Econet) | 8 | 01-ANB02-4008488 | 01-ANB02-4026643 | 01-ANB02-4008488 01-ANB02-4026643 | 18,156 | 27,000 | 27,000 (18,156) |
AB Model B (Disc) | 114 | 01-ANB03-5000323 | 01-ANB03-5064128 | 01-ANB03-5000323 01-ANB03-5064128 | 63,806 | 64,500 | 64,500 (63,806) |
AB Model B (Disc & Econet) | 10 | 01-ANB04-6003024 | 01-ANB04-6019439 | 01-ANB04-6003024 01-ANB04-6019439 | 16,416 | 19,500 | 19,500 (16,416) |
Wong Model B | 35 | 02-B01-203073 | 02-B01-223856 | 02-B01-203073 02-B01-223856 | 20,784 | 24,000 | 24,000 (20,784) |
Wong Model B (Disc) | 14 | 02-ANB03-1000336 | 02-ANB03-1009428 | 02-ANB03-1000336 02-ANB03-1009428 | 9,093 | 9,500 | 9,500 (9,093) |
Race Model A/B | 66 | 300229 | 324313 | 300229 324313 | 24,085 | 24,500 | 24,500 (24,085) |
Race Model A | 7 | 03ANA01 1000170 | 03ANA01 1005390 | 03ANA01 1000170 03ANA01 1005390 | 5,221 | 5,500 | 5,500 (5,221) |
Race Model B | 151 | 03ANB01 3001407 | 03ANB01 3097910 | 03ANB01 3001407 03ANB01 3097910 | 96,504 | 98,000 | 98,000 (96,504) |
‘06’ Model B | 2 | 06B01 100301 | 06B01 100808 | 06B01 100301 06B01 100808 | 508 | 1,000 | 1,000 (508) |
‘07’ Model B | 84 | 07-ANB01-3752460 | 07-ANB01-3790575 | 07-ANB01-3752460 07-ANB01-3790575 | 38,116 | 41,000 | 41,000 (38,116) |
‘07’ Model B (Econet) | 1 | 07-ANB02-4000787 | 07-ANB02-4000787 | 07-ANB02-4000787 07-ANB02-4000787 | 1 | 1,000 | 1,000 (1) |
‘07’ Model B (Disc) | 10 | 07-ANB03-5000001 | 07-ANB03-5005054 | 07-ANB03-5000001 07-ANB03-5005054 | 5,054 | 5,500 | 5,500 (5,054) |
‘07’ Model B (Disc & Econet) | 5 | 07-ANB04-6000468 | 07-ANB04-6005207 | 07-ANB04-6000468 07-ANB04-6005207 | 4,740 | 5,500 | 5,500 (4,740) |
Keltek Model B | 95 | 08-ANB01-3000125 | 08-ANB01-3025503 | 08-ANB01-3000125 08-ANB01-3025503 | 25,379 | 26,000 | 26,000 (25,379) |
Keltek Model B (Disc) | 2 | 08-ANB03-5051464 | 08-ANB03-5051474 | 08-ANB03-5051464 08-ANB03-5051474 | 11 | 1,500 | 1,500 (11) |
Keltek Model B (Disc & Econet) | 2 | 08-ANB04-6025023 | 08-ANB04-6025111 | 08-ANB04-6025023 08-ANB04-6025111 | 89 | 500 | 500 (89) |
‘09’ Model B | 3 | 09-ANB01-3000068 | 09-ANB01-3000567 | 09-ANB01-3000068 09-ANB01-3000567 | 500 | 1,000 | 1,000 (500) |
‘09’ Model B (Disc & Econet) | 1 | 09-ANB04-6000006 | 09-ANB04-6000006 | 09-ANB04-6000006 09-ANB04-6000006 | 1 | 500 | 500 (1) |
‘21’ Model B | 1 | 21-ANB01-0001326 | 21-ANB01-0001326 | 21-ANB01-0001326 21-ANB01-0001326 | 1 | 1,500 | 1,500 (1) |
‘21’ Model B (Disc & Econet) | 1 | 21-ANB04-0001039 | 21-ANB04-0001039 | 21-ANB04-0001039 21-ANB04-0001039 | 1 | 1,500 | 1,500 (1) |
‘ANB100’ Model B | 18 | ANB100 100070 | ANB100 102821 | ANB100 100070 ANB100 102821 | 2,752 | 3,000 | 3,000 (2,752) |
1,289 | 557,023 | 584,500 | 584,500 (557,023) | ||||
*AB Electronics serial numbers of 200000 and above were assigned to PCBs only. These PCBs were used in machines with serial numbers in the 01-ANB01 and 01-ANB03 ranges, effectively giving the machine two different serial numbers. The case serial number is what gives the machine its identity, so PCBs with an AB serial number of 200000 and greater are not counted towards production totals; they are instead counted within the 01-ANB ranges.
Model B Clone - Total Produced: 8,500
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
Dolphin Hope | 0 | 0 | 0 | 0 (0) | |||
SCL Unicorn Model B | 3 | 0007502 | 0008058 | 0007502 0008058 | 557 | 8,500 | 8,500 (557) |
3 | 557 | 8,500 | 8,500 (557) | ||||
Model B (Export) - Total Produced: 13,000
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
Wong Model B (Germany) | 5 | 02-GNB14-1000770 | 02-GNB14-1001285 | 02-GNB14-1000770 02-GNB14-1001285 | 516 | 1,500 | 1,500 (516) |
Wong Model B (USA) | 20 | 02-UNB09-1000204 | 02-UNB09-1011220 | 02-UNB09-1000204 02-UNB09-1011220 | 11,017 | 11,500 | 11,500 (11,017) |
25 | 11,533 | 13,000 | 13,000 (11,533) | ||||
Model B+/B+ 128K - Total Produced: 35,500
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
AB Model B+ | 8 | 01-ANB51-3501245 | 01-ANB51-3508655 | 01-ANB51-3501245 01-ANB51-3508655 | 7,411 | 9,000 | 9,000 (7,411) |
AB Model B+ (Econet) | 2 | 01-ANB52-4500374 | 01-ANB52-4500532 | 01-ANB52-4500374 01-ANB52-4500532 | 159 | 1,000 | 1,000 (159) |
AB Model B+ (Disc) | 38 | 01-ANB53-5501367 | 01-ANB53-5520478 | 01-ANB53-5501367 01-ANB53-5520478 | 19,112 | 20,500 | 20,500 (19,112) |
AB Model B+ (Disc & Econet) | 0 | 0 | 0 | 0 (0) | |||
AB Model B+ 128K (Disc) | 14 | 01-ANB55-7500021 | 01-ANB55-7504782 | 01-ANB55-7500021 01-ANB55-7504782 | 4,762 | 5,000 | 5,000 (4,762) |
62 | 31,444 | 35,500 | 35,500 (31,444) | ||||
Master Series - Total Produced: 259,500
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
AB Master | 398 | 01-AMB15-0010674 | 01-AMB15-0260546 | 01-AMB15-0010674 01-AMB15-0260546 | 249,873 | 251,000 | 251,000 (249,873) |
AB Master ET | 8 | 01-ADB12-0100869 | 01-ADB12-0105058 | 01-ADB12-0100869 01-ADB12-0105058 | 4,190 | 5,500 | 5,500 (4,190) |
AB Master AIV | 7 | 01-AVC12-0100431 | 01-AVC12-0102177 | 01-AVC12-0100431 01-AVC12-0102177 | 1,747 | 2,500 | 2,500 (1,747) |
‘30’ Master Domesday | 1 | 30-AVC12-1000018 | 30-AVC12-1000018 | 30-AVC12-1000018 30-AVC12-1000018 | 1 | 500 | 500 (1) |
414 | 255,811 | 259,500 | 259,500 (255,811) | ||||
Master Compact - Total Produced: 55,000
Group | Count | Lowest | Highest | Lowest / Highest | Range | Est. Total | Est. Total (Range) |
---|---|---|---|---|---|---|---|
‘07’ Master Compact | 7 | 07-ADB10-1000232 | 07-ADB10-1004284 | 07-ADB10-1000232 07-ADB10-1004284 | 4,053 | 4,500 | 4,500 (4,053) |
‘07’ Olivetti Prodest PC 128S | 2 | 07-AIB10-2014396 | 07-AIB10-2018543 | 07-AIB10-2014396 07-AIB10-2018543 | 4,148 | 19,000 | 19,000 (4,148) |
‘25’ Master Compact | 4 | 25-ADB10-1000102 | 25-ADB10-1001378 | 25-ADB10-1000102 25-ADB10-1001378 | 1,277 | 1,500 | 1,500 (1,277) |
‘27’ Master Compact | 37 | 27-ADB10-0100196 | 27-ADB10-0129484 | 27-ADB10-0100196 27-ADB10-0129484 | 29,289 | 29,500 | 29,500 (29,289) |
‘30’ Master Compact | 1 | 30-ADB10-1000067 | 30-ADB10-1000067 | 30-ADB10-1000067 30-ADB10-1000067 | 1 | 500 | 500 (1) |
51 | 38,768 | 55,000 | 55,000 (38,768) | ||||