Suunto Vyper Interfaces


My trials and tribulations with DIY Suunto Vyper Interfaces



Steve Prentice's Version


This is the first one I tried. Unfortunately I encountered problems along the way. Firstly the transistor Steve uses is no longer produced**, however someone with a bit more electronics knowledge than me (which really isn't much) will no doubt find an alternative, I was lucky enough that my local(ish) Maplin's Store had one.


** Thanks to Danny Burchett for pointing out that just because Maplin say it's not produced anymore doesn't necessarily mean that is the case - the part in question is listed on and probably a few other places besides.


Secondly, I foolishly assumed that what Maplin's listed as "Stripboard" was the same as Veroboard. It isn't. I had to attempt to figure out my own layout based on Maplin's Stripboard. I got it in the end.


Finally, when the layout was completed, and the board built Suunto's Dive Manager wouldn't recognise it.


This it seems is due to my use of a laptop which only provides the circuit with around 6V instead of the 9V it needs.


With help from Nigel Hewitt and Charlie Allen from UKRS I discovered that the addition of two PP3 batteries should get it to work. I haven't tried it yet but will update this once I do.


Anyway the final layout looks like this....


click to enlarge Item Quantity Type Maplin's Code
R1, R2 & R3 3 470 M470R
R4 & R5 & R7 - R10 6 33K M33K
R6 1 50K Variable WR50E
D1 - D6 6 1N4001 QL73Q
D7 - D10 4 1N4148 QL80B
D11 1 BZY 4V7 QH06G
Q1 1 BC214 QB62*
U1 1 LM358 UJ34M
C1 & C2 2 22uF 16V VH09K


* BC214L's are out of production - you can only get them buy ringing round Maplin stores. If anyone with electronics knowledge can suggest an alternative I'll list it here.


Although this is the back of the Stripboard I've done it like this to show you where all the components are connected. When you build it the top of the board should look like the layout, that is, apart from the obvious caveat - I haven't got it to work yet!!!


And here is the quote from Charlie Allen about the batteries...


"You can battery power the circuit using two 9V batteries. The first battery is negative to ground (pin 5 on connector), + end to +9V point (where D1, D2, D3 join together). The second battery is positive to ground, - to -9V point (junction of D4, D5, D6).


If you are only using it with your laptop, you don't even need to disconnect the diodes. They will be reverse biased and won't allow current to flow."




Roli's Version


Again I had to develop the layout for use with Stripboard but it proved nice and easy by comparison with the Steve Prentice version. In fact it proved so easy that I had it designed and built inside two hours (needless to say my soldering technique has improved dramatically!), but then building a plug for the Vyper took another four....


This version worked first time on my laptop - I just about fainted given the hassle I had with the other version!

The layout...


Item Quantity Type Maplin's Code
Q1 1 BC547 QQ14Q
Q2 & Q3 2 BC557 QQ16S
D1 1 BZX 4V7 QF45Y
D2, D3 & D4 3 1N4148 QL80B
R1 1 10K M10K
R2 1 27K M27K
R3, R4 & R6 3 22K M22K
R5 1 1K M1K


You will, of course, need other things like stripboard, serial cable, a female serial plug, and other bits and pieces. Be sure to get the PDF file from Roli's site.


Again the picture shows the back of the Stripboard just to show the connections between the components but treat it as if it was the front.



The plug


I tried all sorts of things for the plug but eventually found a plug inside an old knackered telly. It had six contacts and was about an inch and a half long but exactly the right width (about 5mm). So with some hacksawing and chiselling it was pared down so that it slid in from the side of the Vyper (with the boot removed) using the ridges on the Vyper's socket to hold it in place. Two slots were cut to accommodate the Vyper's pins and a notch taken from the plug to accommodate the vertical ridge in the Vyper's socket.


I made the contacts from the spring that you find inside a Clipper cigarette lighter. Pull the striking wheel assembly from the lighter and throw the rest away (it won't work anyway when you do what comes next!). Undo the little plastic screw at the bottom and pull out the spring, you will need about four to six coils of spring for each contact. I soldered them onto bits of wire and fitted them into the plug and just kept on testing and trimming and testing and trimming until they fitted. It is worthwhile stretching the spring out a bit to give more movement when they make contact with the Vyper's pins - the plug pops back out of the socket if the springs don't have enough "give".







Thanks to Bryan for bringing this little omission to my attention during his build of the Roli version...


Assuming that the voltage tests work out about right, you then have to get Suunto's Dive Manager software to recognise the interface.  This poses one problem that crops up again and again - in our "connected age" you will probably have a mobile phone and a PDA that you synchronise with your PC.  They generally have a listener which hogs the COM port and Dive Manager cannot access the interface which you *know* you have physically plugged into COM1!


These listeners usually have an icon in the system tray (start bar - right hand side next to the clock) and right clicking them should bring up a menu allowing them to be shut down.