LagondaNet

[david]

Hello,

This is a bit of an unusual request but I would like to view a functioning CRT instrument display for a project I have going on.

Briefly, I am producing a replica CRT display using LCD screens and a new computer, coupled with the appropriate interface units to fit into a car that was CRT equipped but has had this replaced by an analogue system in the early 1990's.

The system will be dimensionally identical but have the stability of a modern screen. and the functionality and adaptability of a modern computer system.

I can talk about it in much more detail with anyone who is willing to help.

Equally I can describe the principle in more detail here if anyone is interested.

All I need to do is to view the running system, take photographs to record the colour contrast etc and ideally drive it on the road to see how the speedo and rev. counter respond.

This is a project that has been some six months in development so far.

I run a professional workshop so have insurance etc and am prepared to travel.

Roger knows about this project and also myself - if you have any concerns, please contact him and (hopefully!) he will vouch for me.

Please contact me by email, david@davidmarksgarages.co.uk or by phone, 0115 982 2808 or 07850 334 236

Thanks

David Marks

[Mitrovic]

David

Great project! I have a CRT car, but the car is in Switzerland.

Sieghard Schneider and Works Service have both realised LCD screens in CRT cars, may be you would like to contact them?

regards

Zoran Mitrovic

[david]

Hello Zoran,

Thanks for this, yes, any help is always good.

Shame you are in Switzerland but you never know.......!

David

[Lagondanet]

I am happy to vouch for David Marks, a Jaguar engineer, but who has a penchant for our Lagondas, and has serviced a few including my own. His workshops are in Nottingham. David, as Zoran says, Sieghard Schneider in Germany has devised his own LCD set up. You might like to communicate with him & swap ideas (sieghard.schneider@web.de). Let me know how you get on finding a donor car & do ask if you need further assistance.

[billmorrow]

i recently sold to zoran the crt's from my 13394 and the crashed car 13422 along with the computer from 13422..
i had experimented with some cheap LCD displays in place of the crt's but i was unable to easily sort out the size issue between the lcd's and what the computer was expecting..

so i decided to move to a fully functioning aftermarket instrument package from a company called nordskog in los angelea area..
it works quite well except for the lack of all the telltale lights and gear positioning..

so this is where i stopped..
so far..
no telltale lights but the major instruments all work..
the positive side is that there is space for a garmin gps AND all the telltale lights (if i ever get something built up for them)..
the negative side is my electronics knowledge is limited and i am kind of stalled waiting for time and place to learn enough to put something together, or hire a good electronic tech with the ability to design and build what i want..

still and all esther (13394) runs wonderfully as she has only 12k miles still and these cars are, when you drill down past all the electronic widgets, a basic car..
carbs and those silly latching relays..

(a note on the latching relays: these seem to be designed for a 24 volt "system" and when they are used in a 12 volt system they tend to NOT operate well and if aged or slightly "out of sorts" they won't work at all, thus giving this really swell car its bad reputation)

(a further note on the computer: it was designed at a time when such small computers were really basic and new and the technology used was NOT for an automotive environment, so i await further reports from david on his efforts to replace that existing computer with something up-to-date)

all this is to state that zoran might have some parts that can aid you, david, and francis (if he EVER concludes the deal for 13422, the crashed car) might have some parts that will also aid you..

and i still have some parts i removed from 13422 which i intend(ed) to use building a more up to date digital dash..

one additional thought:
since all the inputs for the instruments and telltale lights are pretty basic, either "on" or "off" and there is only one or two analog inputs (like the ambient light sensor to name the only one i can think of at this moment), it should not be difficult to either design a new instrument set or to source an automotive off-the-shelf instrument cluster for the lagonda..

i know there are purists who will want to retain the car in an original state but my "take" on this is these cars are all really "custom made" and thus some small changes from stock are acceptable..

and i am NOT going into the issue that new automotive instruments are driven by a cars computers but there must be some "standards" they all adhear to..

whew, long winded, sorry..

so, david, we're all here to help in hopes that you will come up with something great..
_________________
Bill Morrow, kept by parrots
Sysop - forum.thinkpads.com
*
She was not what you would call refined.
She was not what you would call unrefined.
She was the type of person who kept a parrot.
~~Mark Twain~~

[david]

Hello Bill,

Thanks for your comprehensive reply.

A bit of background:

We have 13501, a fuel injected car, in the workshop, it came in as a non runner with many electrical issues.

Whilst built as a CRT car, it had been converted to analogue instruments by Aston Martin in 1990 or thereabouts for a previous owner.

Once we had the car up and running with the majority of the issues resolved (and there were many!!), we were asked by the current owner if we could reinstate the original instrumentation.

Having had some experience with the inconsitencies (to say the least) of the original set up, coupled with the fact that nothing remained in the car apart from some of the wiring harness I said that to refit the original system would be impractical at least and an expensive mistake at worst, even if all the components (right down to the mounting chassis) could be found.

I then discussed it with my Brother and we came up with a proposal to produce a LCD facsimile, utilising a bespoke computer, running on software produced from scratch by my Brother.

The computer will connect to the LCD's via custom circuit boards.

I was able to purchase an original wood surround for the screens, so the appearance to the driver will be close to original, allowing for the difference between CRT and LCD displays.

We have had to analyse every input from the car (emptying and then refilling the fuel tank one gallon at a time and taking readings from the level sensor was time consuming............), including the frequency of the speedo and rev counter generators.

As the under bonnet odometer was removed by Aston Martin (it now sits in the anaolgue speedo but the electric drive from the gearbox is still present), we have taken advantage of a modern computer system and in house programming to enable the trip meter to display vehicle mileage for ten seconds after ignition on and then it will revert to the previous trip dsiplay.

We have also configured the speedometer screen refresh so that it will not continually hunt at about 80 MPH - something I found very annoying on a car I drove a couple of years ago or so.

So, as you can see, this is much more than just screen replacement and, if the owner desires, there can be different styles of display, eg, the speedo and rev counter could be produced as circular dials on the screens and as with any modern computer system, the possibilites are almost endless.

The system will also have the audio warnings and all the various levels of priorities on the message centre will be adhered to.

It will interface fully with the touch binnacles for trip and clock reset etc and display dimming will function via the original rheostat.

Hope this explains things in more detail but I must say that we have a long way to go before the system is fully installed in the car.

We want to see an original car to get a "feel" for the colours and interaction etc as it is some time since I have seen one.

I have found one in London and hope to see it this weekend, it is not functioning correctly but should be enough to give us a start.

I agree with you Bill about the custom made feel and hope that what we are doing will fit in with the original design concept of the car.

David

[Mitrovic]

David this sounds great! Lot of work! Bravo!

If you find the time ( there are rather cheap flights ) you could come to Switzerland and I could show you my car. The CRT's work flawlessly, they just have been repaired after last hot summer. There is also Adrian Peter's car in the neighboorhood you could look at, too. The only thing which does not work on my screens is, it does not switch to the upper scale when driving faster then 160 Km/h.

Or you could come to Lindau and see the approach made by Sieghard, too.

May be Roger can put you in touch with the converted car by Aston Servive and their LCD solution?

Regards

Zoran

[david]

Hello Zoran,

Thanks again for the offer, it woudl be nice to do it some time, if I can make the time I'll contact you again.

It would be good to see different solutions to these problems as well.

I managed to see a car in London so have all the information required from a functioning vehicle.

Nothing comes to mind about your non refreshing screen but a couple of questions that may help are:

Does the bar graph stop at 160 KPH or continue right to the top of the screen?

Does the screen flicker at all when it should change over?

Regards for now

David

[blacky]

Hello David,

here is a photo of my LCD converted Lagonda (#13498).

http://www.astonmartinlagondas.com/P8270437.JPG

You see the screen for speeds exceeding 160 km/h. When going exactly 160 km/h, the screen may flicker between the two settings.

I have used the original Javelina computer and its original 3 video outputs (BNC cable, signal is NTSC (North American) television standard, black and white, 60 Hz. In my car, I can switch the screens to different colours, green, red, blue, white or intermediate colours. I use 5 in. LCD multistandard television screens. They are bigger than the original ones. Contrast settings create some problems. Also LCD screens create ambient light, illuminating the cockpit at night. Dimming LCDs is not easy, either. Displays show startup screens by their manufacturer when switching ignition on, this is annoying. So my solution is 80% OK, but not 100%.

For more questions, please feel free to contact me via sieghard.schneider@web.de.

I am planning to substitute the LCD´s by Nordskog instruments. It would be very helpful for me to know more about what cable is carrying which signal. Would be great if you could share your experiences with me!

Greetings from Southern Germany,
Sieghard.