Start with the fun bit! Here's a short Organiser II buying guide I produced myself - consult the websites for more detailed/informed insights...

There are four models of Organiser II - all should work with this project. I own two Organisers - a 1988-89 CM model and a 1987 XP model.

1. The CM with 8K RAM and a two-line display, introduced in 1986. This was the basic 'consumer' model throughout the Organiser II's life. Be aware that some program packs do not run on the CM owing to lack of memory e.g. the Pocket Spreadsheet.

2. The XP, introduced in 1986 and quickly upgraded. Very early XPs have 16K RAM, all others have 32K RAM. All XPs have two-line displays. From 1986-89 XPs were the top of the range Organisers; from 1989 they were demoted to mid-range status. I believe XP means 'executive & professional' - very 80s!

3. The LZ with 32K RAM, a larger range of built-in programs, and a fancy four-line display, introduced in Spring 1989. This was the deluxe model, and was only surpassed by...

4. The LZ64 with 64K RAM, otherwise the same as the LZ. Introduced in Spring 1989.

You may also see 'P250' or 'P350' branded models. These were Organisers intended for use in industry; usually they were designed to run a single software package but some can be 'hacked' back into normal Organisers. If in doubt, avoid!

Also bear in mind some LZ64s seem to suffer from a 'buzzing capacitor' problem - again if you're not confident in fixing this you may wish to avoid this model...

(to be continued)

The HC06 Bluetooth adaptor is quite simple to get hold of. They are all over the internet at dirt-cheap prices. Check reviews and images though to make sure you're getting a decent one. Mine cost £3.85 in February 2020 from a UK seller.

The Comms Link is a vintage device, so it's harder to get hold of. It plugs into the top of the Psion and allows it to connect to a PC via an old-fashioned serial cable. The design and firmware of the Comms Link was updated during the Organiser II's long life. The Comms Link device itself is a grey, square-ish box with 'Comms Link' written on it.

Be careful: you do not want a Psion 3Link, which was designed for the later Series 3, introduced in 1991. Nor do you want anything with the word 'parallel' in the name, unless you happen to be a vintage printer enthusiast! If your Comms Link looks like a Comms Link but has 'RS232 Link' written  on it, you are looking at a very early 1986/87 model which might have more bugs and less functionality.

I believe all Comms Links work with all Organiser IIs, except perhaps these early RS232 Links. If you have an LZ or LZ64 you might like to look for a later version of the Comms Link which can take advantage of the 4-line display. These can be identified easily as they have a little red LED in the corner, whereas the earlier 2-line Comms Links do not.

Prices of Comms Links vary and availability is quite limited on eBay. Your best bet might be to browse Organiser II listings to see if someone is throwing in a Comms Link. That way you'll get a spare Organiser as well! I bought my Comms Link along with a battered Organiser CM for about £16 in summer 2019.

Before modifying the Comms Link, now is a good time to get to grips with the Organiser II itself. It's a really impressive machine for its time and can still be useful today. I do not own an LZ/LZ64 so I'll give a quick runthrough of the menu options on a CM/XP.

FIND/SAVE - allows you to compile a simple database of 'records' i.e. stuff. Try navigating to SAVE and press EXE - the screen says 'SAVE A:' and type in 'Stuck in 80s handheld computer - send help!'. Hit ENTER. Now go to FIND. Enter 'handheld' and hit EXE. Your message is displayed. The Organiser II has searched its database for every record with 'handheld' in it (FYI - not case sensitive) and will display these one at a time. Hit EXE and it'll say 'END OF PACK' which means it has run out of records with 'handheld' in them.

DIARY: A simple yet useful diary which splits eternity into 30 minute segments. Use the arrow keys to navigate through the endless mists of Time and press EXE to enter a diary entry on some random day in the late 80s. It can even ring an alarm for you in advance. For serious use you'll need the Y2K fix (see later).

CALC: Remind yourself that 1+1 = 2 with the OrgII's handy calculator. The keyboard defaults to 'numeric & symbols' mode but you can use trig functions etc by hitting SHIFT and the down arrow to go back into 'letters mode', then entering SIN, COS etc.

PROG: Enter the wonderful world of OPL programming. Read the manual to find out more.

ERASE: Delete outdated, incriminating or embarrassing files from your Organiser.

TIME: Tells you the time and date. By default it'll probably have woken up on New Year's Day 1986, 1987 or 1988 (a good way of working out the rough age of your Organiser!) and it won't let you go past the millennium. A Y2K fix is available at Jaap's website, but you'll need a non-full datapak and a functioning Comms Link. (Datapaks are cheap on eBay, and a 16K one is all you'll need for this.)

INFO: Tells you how much room you have left on your Organiser (yes, I'm afraid that figure is in bytes) and any datapaks you have installed.

ALARM: 8 alarm clocks in your pocket, as the ads used to say. Genuinely useful even today. Quite loud as well.

COPY: Copy stuff from your Organiser to a datapak, or a datapak to the Organiser. Hours of fun for all the family.

RESET: Want to annoy a retrocomputing enthusiast? Use this option to restore their Organiser II to its factory settings and delete all files. 

OFF: When the fun is over, switch the Organiser II off. (PS: hitting the 'O' key does this quickly, provided you're at the main menu.)

The next step is to physically connect up the HC06 Bluetooth chip to the Psion Comms Link.

To find out how to do this, I looked at the diagram at this (now sadly Wayback-only) page: http://web.archive.org/web/20180411125903/http://archive.psion2.org/org2/topgen.htm. When I refer to 'Psion pin x' I am referring to this diagram.

The power setup is fairly easy - connect the VCC pin on the HC06 to Psion pin 12 and the GND pin on the HC06 to your choice of Psion pin 1, 2 or 13. Once you've made these two connections, switching on your Psion and entering the COMMS menu should cause the light on your HC06 to briefly flash, indicating that power is being supplied from the Comms Link to the HC06. If you enter 'TERM' mode in the  COMMS menu, the light on the HC06 should flash persistently. Hooray!

We'll move on to the trickier bit - the TXD/RXD connections from HC06 to Psion & vice versa - in the next step...

I created my Bluetooth-ed Comms Link back in February. When connecting the HC06 TXD/RXD pins to the Psion Comms Link, I remember the connections being a bit complicated.

When I came back to the project a few weeks ago (in November) I thought to myself 'oh, all that fiddling around was unnecessary! All I needed to do was to connect Psion pin 7 to the HC06 RXD pin and Psion pin 8 to the HC06 TXD pin!'

Now, however, I remember why I made things more complicated than that...

Psion pins 7 & 8 deal with RS232 signals, whereas the HC06 works with 3.3V TTL signals. The two signal types are incompatible, as far as I know, and I was worried that the higher voltages involved with RS232 might be incompatible with (and likely cause damage) to the HC06. Please note I'm not an expert in this sort of thing!

I therefore connected the TXD/RXD pins of the HC06 to two other points on the board. These connection points definitely work, but sadly I cannot remember what made me choose them. I think it was trial-and-error, but if so I must have been very lucky to get it right first time! Perhaps I found an old schematic online somewhere.

(Important Life Lesson: always write your instructions when you can remember why they work, instead of nine months later!!)

The HC06 TXD pin is connected directly to the board, whereas the HC06 RXD pin is connected to the board via a potential divider, which I included as I believe the Psion Comms Link works with 5V TTL whereas the HC06 works on 3.3V TTL.

Further details & a diagram showing the two TXD/RXD connection points to follow...

(note to self: The HC06 TX pin connects to the first hole directly to the left of Psion pin 8. The HC06 RX pin connects to the first hole directly to the left of Psion pin 12, via a potential divider.)