Serial Numbers
BBC Micro serial numbers fall into two broad categories: numeric and structured. Numeric serial numbers were used until roughly August 1983, when they were replaced by structured serial numbers.
Numeric Serial Numbers
Numeric serial numbers were used by five different manufacturers. These serial numbers are six digits long, with blocks of 100,000 being assigned as follows:
| Range | Manufacturer | Example |
|---|---|---|
| 000001 - 099999 | ICL | 012345 |
| 100001 - 199999 | Cleartone (later AB Electronics) | 101234 (Cleartone), 112359 (AB) |
| 200001 - 299999 | Wong’s Electronics | 200743 |
| 300001 - 399999 | Race | 312345 |
When Cleartone was taken over by AB Electronic Systems, AB continued to use Cleartone’s serial number range. The highest known Cleartone serial number is UNKNOWN_0401 and the lowest known AB serial number is 112359.
Some AB machines have PCBs with serial numbers higher than 199999, but these are housed in a case with a structured serial number. The serial number on the case gives the machine its identity so this avoids a clash with Wong serial numbers. However, very few machines were built by Wong before they adopted structured serial numbers.
Although AB Electronics exhausted their entire serial number range — and even went beyond it with PCB serial numbers — the other manufacturers did not use their entire allocation. The highest known numeric serial numbers for each manufacturer are:
| Manufacturer | Highest Known Serial Number |
|---|---|
| ICL | 029779 |
| Cleartone*/AB | 199714 (or UNKNOWN_206430 on a PCB with an accompanying serial number in the ANB range) |
| Wong’s Electronics | 200743 (Wong’s structured serial numbers continued using the same range) |
| Race | 324313 |
*The highest known Cleartone serial number is UNKNOWN_0401.
When structured serial numbers were introduced, manufacturers were assigned two digit codes. In the case of AB, Wong and Race, these codes were based on their numeric serial number range allocations. AB became ‘01’, Wong ‘02’ and Race ‘03’.
Numeric serial numbers do not encode the type of machine (Model A or Model B) within the number. This means that it is not possible to definitively know a machine’s configuration from a numeric serial number alone. However, it is possible to generalise:
- Most ICL machines are Model B. Some machines with serial numbers lower than 005000 are Model A.
- All Cleartone machines are Model A, except for a few Issue 1 Model Bs.
- Most AB machines with a serial number above 115000 are Model B. Lower numbers are likely to be Model A.
- All Wong machines are Model B.
- Most Race machines are Model B, but some are Model A.
Examples of Numeric Serial Numbers
ICL
The serial number labels on the cases of approximately the first 1,000 machines produced by ICL had the company’s logo removed. This appears to have been done by cutting the label after it had been applied to the case:
The PCB also had a serial number label which sometimes retained the ICL logo. The remaining 29,000 machines built by ICL had a complete label on the case:
Cleartone
Cleartone’s serial numbers are dot matrix printed on plain white labels. The labels appear to be hand-cut from a larger sheet.
AB
Numeric serial number labels used by AB are identical in style to Cleartone’s, due to the fact that AB took over Cleartone’s manufacturing facility. The earliest labels show the company’s name as AB ELECTRONIC SYSTEMS PCL.:
The error is corrected between serial numbers 114420 and 114437:
Between serial numbers 148263 and 151920, PLC is changed to Ltd:
Race
Race serial number labels are pre-printed with Race’s logo in blue, with the number stamped on in a closely-matching colour. It is a shame that the logo did not continue to be used on the company’s structured serial number labels.
Structured Serial Numbers
Structured serial numbers encode more information than their numeric counterparts. They contain the manufacturer, product type and model and also have the advantage — to Acorn, at least — of concealing the name of the subcontracted firm which built the computer.
Various formats were used, possibly because the standard was only loosely enforced by Acorn, or possibly because the manufacturers’ serial numbering equipment limited what what they were able to put on the label. However, Acorn’s structured serial numbers are usually in the following format:
MM-PPPPP-NNNNNNN
An example serial number is 01-ANB01-3012345. The parts are broken down as follows:
| Part | Description | Format | Example |
|---|---|---|---|
| MM | Manufacturer code | Two digits | 01 |
| PPPPP | Product code | Three letters followed by two digits | ANB01 |
| NNNNNNN | Serial number | Seven digits | 3012345 |
Additional information is encoded within the product code (PPPPP). Its internal format can be expressed as TTTVV:
| Part | Description | Format | Example |
|---|---|---|---|
| TTT | Product type | three letters | ANB |
| VV | Product variant | two digits | 01 |
In the example above (ANB01) the product type is ANB (BBC Model B) and the product variant is 01 (no disc or Econet interfaces fitted).
There are also some constraints on the serial number part (NNNNNNN): the first two digits are determined by a combination of the manufacturer code and product code. The table below shows how this is applied to serial numbers in the 01-ANBxx range.
AB Electronics 01-ANB Serial Number Ranges
| Manufacturer and Product Code | Serial Number |
|---|---|
| 01-ANB01 | 30xxxxx |
| 01-ANB02 | 40xxxxx |
| 01-ANB03 | 50xxxxx |
| 01-ANB04 | 60xxxxx |
As with any well-defined system, there are exceptions. Various manufacturers used serial numbers which do not fit into the MM-PPPPP-NNNNNNN, notably Wong, which abbreviated the ‘ANB’ product type to ‘B’ and the mysterious ANB100 range which lacks a manufacturer code altogether.
All known types of structured serial number are listed below.
Examples of Structured Serial Numbers
01 and 07: AB Electronics
AB’s structured serial number labels are white with a black border. The adhesive is not particularly strong so many of this type have fallen off over the years. The digits zero and one in the manufacturer and product codes are actually a capital letter ‘O’ and ‘I’, though the reason why this was done is unknown.
AB were also allocated the ‘07’ manufacturer code for products built at their factory in Rogerstone, Gwent.
02: Wong
Manufacturer code 02 belonged to Wong’s Electronics in Hong Kong.
The first structured serial numbers issued by Wong’s Electronics use a shorter product code and only six digits in the serial number section, instead of the more usual 7. These seem only to have been used on UK-specification Model B machines
The format is MM-PPP-NNNNNN, giving serial numbers that look like this: 02-B01-212345. Only the final letter of the product code is used, with ANB being shortened to B. The first digit of the serial number is still fixed, and in this case it is a 2.
Wong later adopted the standard format for their structured serial numbers, and this can be found on later UK-specification machines as well as the export specification Model B machine for the US and German markets. Wong were the only manufacturer that produced US and German specification machines.
03: Race
Race serial numbers omit the dash between the manufacturer code and product code and put the serial number on a second line.
These serial numbers are usually written in the format MMPPPPP NNNNNN, with no dashes and a space before the serial number component. A typical serial number looks like this: 03ANB01 3012345.
06: Astec
There are very few examples of this type of serial number and they have only been seen on Model B machines. The manufacturer is likely to be Astec. This is based on the fact that Astec are known to have made Acorn Electrons in their Malaysian factory, and those machines have serial numbers beginning with 06-ALA.
The serial number format is similar to Wong - MMPPP NNNNNN - but omits the first dash and replaces the second with a space, being written as follows: 06B01 112345.
Like Wong, the serial number component is six digits instead of seven. The initial digit is always 1.
08: Keltek
Keltek is the only manufacturer whose name appears on a structured serial number label. The majority of the company’s output was Issue 4 Model Bs, all with serial numbers in the 08-ANB01 range. The serial number labels for these machines look like this:
Keltek also produced some computers with ANB03 and ANB04 product codes (Model B with disc interface and Model B with disc and Econet interfaces respectively). The serial number labels for these are dot matrix printed:
09: Unknown
Manufacturer 09 uses labels with look similar to Keltek’s. Unfortunately there is no manufacturer name so it is not possible to know which company produced these computers.
ANB100
The ANB100 serial numbers do not conform to any of the formats described above. They are all applied to Model B machines with an Issue 7 board.
The format is ANB100 NNNNNN, meaning that there is no specific component which identifies manufacturer. It consists simply of a shortened ANB01 product code with two additional zeros, followed by a 6-digit serial number. The first digit is always 1 and it is possible that the second digit is always 0, giving space for a range of only 0 to 9999 for the serial number itself.