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Zel's Motoring Adventures...Volvo, Renault, Rover, Trabant, Invacar & A Sinclair C5 - Updated 13/11.


Zelandeth

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8 minutes ago, Zelandeth said:

So I'd need to switch to 12" wheels.  Which I really would rather not do.

another problem with that would be finding a 12 inch wheel with the right offset

otherwise your going to have problems with the front wheel being off set to one side by too much!

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I wasn't expecting  normal at all !   I think you will find that Whit and BSF  generally, though not always, use the same size hex. heads. .

My logic was this:  it would be better to use a coarser thread than UNF into the hub, as it would be more suited to the cast material.  In imperial threads the options would be UNC, Whit or BSF.  Practically the whole UK/US motor industry was standardised on UNC/UNF by the 1950s.  BSF and Whit were obsolete by then, but were used on earlier British cars, and it is quite possible that AC would have had BSF tooling in stock.  In fact BSF at 20 tpi might be preferable in a relatively thin hub flange than UNC at 16tpi.  Looking at Zel's old stud it does not look as coarse as 16tpi on the short end, but might possibly be 20tpi, hence BSF.

If you have found Whit/BSF size heads on an engine  bracket, I bet the threads are BSF and that would tend to confirm things.  I think that makes sense - maybe someone else could comment?

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20 hours ago, Zelandeth said:

[] Temperature probe reading nonsense (see 160C reading above).

I can't help with the threads, but I should be able to with the temperature probe seeing as I've worked in that industry for years. Do you know what type it is? I.e. thermocouple (voltage) or a resistance type. The former is generally more robust, but involves a more complex measurement circuit. You would be able to tell by shorting out the probe terminals - a thermocouple system will read ambient temperature (assuming working correctly) but a resistance system will read either full scale high or low depending on whether NTC or PTC.

I'm finding this fascinating, even more than the vehicles!

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26 minutes ago, mat_the_cat said:

I can't help with the threads, but I should be able to with the temperature probe seeing as I've worked in that industry for years. Do you know what type it is? I.e. thermocouple (voltage) or a resistance type. The former is generally more robust, but involves a more complex measurement circuit. You would be able to tell by shorting out the probe terminals - a thermocouple system will read ambient temperature (assuming working correctly) but a resistance system will read either full scale high or low depending on whether NTC or PTC.

I'm finding this fascinating, even more than the vehicles!

I haven't done too much investigation on that yet - disconnecting the probe for it drops the reported temperature down to around 80C.  I have a sneaking feeling that there's a missing or way out of whack reference voltage rail somewhere which is probably what's throwing a whole load of the measurements off.  I've not even looked at the analogue front end side of things yet.

At least a couple of the boards are liberally scattered with tantalum decoupling capacitors as well...these are famously unreliable and could well be leaky and dragging one or more of the supply rails down.  Given the record of these things I may well just replace these on sight in the interests of future proofing/long-term reliability.  If it fixes any issues along the way it's a bonus.

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6 hours ago, Zelandeth said:

Fluffing Hell...this is the problem that just keeps on giving.

The thread in the hubs that the studs screw into on the Invacar is NOT 3/8" UNF apparently.

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Really wish I could just find another hub at this point and be done with it.

I'd second the BSF hypothesis, got to be worth a shot; the thread damage certainly looks like it's gone into a thread the same diameter and smaller TPI/greater pitch.

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Well I'll order some 3/8" BSF bolts.  For the sake of a few quid it's worth a shot.

If they don't immediately screw in perfectly I'm pulling the hub off.

It will then be sent over to the fabricator who made me the fuel tank with the instruction to do the machining work necessary to make it use sensible wheel nuts.  Whether that means machining a land in the back surface of the hub to allow splined studs to be used or drilling and tapping it for metric wheel bolts...to be honest I've little interest in...this is one of those things which I just want to work!

Had kind of hoped a spare hub might have surfaced by now, sadly not to be it seems.

There are a million things I would rather be doing with this car than faffing around with bloody wheel studs three months in.  Would really like to be able to drive it again now please...

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39 minutes ago, Zelandeth said:

Well I'll order some 3/8" BSF bolts.  For the sake of a few quid it's worth a shot.

 

I just hope the thread(s) in the hub have not been mangled by the 3/8th UNF bolt

39 minutes ago, Zelandeth said:

There are a million things I would rather be doing with this car than faffing around with bloody wheel studs three months in.  Would really like to be able to drive it again now please...

you and me both! Id of really have liked to have made more progress with REV then I have so far, but sadly things just did not work out in my favour

still hoping I can get the fuel tank removed sometime before the main "fix it" day so I can get a head start on that at least! (as I dont want to have everything ready to go on REV only to be fouled up by the fuel tank)

as I think the fuel tank on REV is the only "major" component that need/may need serious specialist outside attention, the rest is thankfully fairly minor stuff, hopefully! famous last words....

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Argh!

I'm coming down with a cold.  Not unexpected as everyone else in the house has had it.

This has made getting to sleep even harder than usual.  Just after 0600 I was finally starting to feel restful and that I had some hope of dozing off at some point soonish.  Right up to the point where I coughed.

Now I have the goddamn hiccups.  Which are doubly fun with an already sore as hell throat and sore chest because I've been coughing all day.

Friday is going to be a long day I fear.

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After what should have been an hour or two round trip taking nearly the whole afternoon because of sodding traffic, have a correct replacement part for the Sun 1215 and a spare for the future.

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Apparently the seller does indeed have about a thousand of them, so worth keeping an eye on their page LBF if they offer delivery.  I never checked that as they were just 15 miles or so down the road.

Will get that installed shortly.

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27 minutes ago, Zelandeth said:

After what should have been an hour or two round trip taking nearly the whole afternoon because of sodding traffic, have a correct replacement part for the Sun 1215 and a spare for the future.

IMG_20191122_161426.thumb.jpg.e530c7fdce0d3dd62e9ab6f750046f4a.jpg

Apparently the seller does indeed have about a thousand of them, so worth keeping an eye on their page LBF if they offer delivery.  I never checked that as they were just 15 miles or so down the road.

Will get that installed shortly.

ah awesome that they were close enough to be picked up personally much reduced risk of them getting smashed! :) 

they do indeed offer delivery, or did for the 1 listing they had

ill keep an eye out on their ebay page, maybe depending on if they are willing to do a bulk discount, I could see myself picking up an entire case of them at some point in time :) 

I wonder where they came from or what they were ordered for, as mentioned previously 30W T12s are very uncommon here and most people dont even know they existed

 

its worth noting that they are very  late GTE tubes, of a transitional design, they have the 1980s GTE etch, but later mid 1990s stepped end cap design, the date code comes back as Aug 1993 if im reading it correctly :) 

(by 1993 I think osram had already acquired GTEs lighting division in the US)

 

it will be interesting to see if now with proper rapid start tubes, you get a proper rapid start fade in as the cathodes warm up to temperature and the striking voltage drops over a second or so :) (im not surprised the F30T8 started instantly as it would of been cold starting due to the lack of proper cathode heating)

 

on that note, due to the low cathode heating voltage of 3.6V its important you make sure the socket contacts are clean and making good contact!

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Worth dropping the seller a question through eBay asking if they're planning on listing any more.

New lamp was fitted without incident.  Still instant starts... suspect this may be one of those ballasts which is a bit brutal about starting.

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Realised that one thing I didn't check last time I had this opened up was whether the back of the diffuser was clean...not really was the answer.

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Everything back together.

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Figured for those interested in the procedure in setting this thing up I'd run through it without missing a bunch of steps, as previously I'd very much abbreviated it.

This isn't a full user guide...but is a quick run through of the real basics from what I remember of using the one a mate had about 20 years ago and what I've seen messing around with this one. 

Hopefully this will demystify all those buttons a bit.

When first powered on the machine shows a message informing you that it has started its warmup phase and gives a countdown to when it will be ready to use.

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You can bypass this delay at any point by pressing #, but there's obviously a greater chance of the accuracy of the machine may drift as it warms up.  The fifteen minute delay helps ensure that everything is stable before you put it into use.

The # button basically functions as the "next page" control throughout.

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When the countdown runs out it waits for you to press # to continue before it will move on to the self test/calibration screen.

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This takes a minute or so to run through...and obviously has a few errors reported in the case of my machine... hopefully these will disappear as time goes on and I work through things.

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Next page is the program setup screen where things start to get a little more interesting.

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The "set ignition selector" relates to two modes that the ignition side of things can run in.  There's a table in the operator's manual telling you which cars which setting should be used with.

This is selected using this button.

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Shown above in mode 1, and below in mode 2.  Yes, this is a bit of an excuse to show off the flipdot indicators...even if they are a bit grubby at this stage.

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"Set 2 or 4 cycle"  is asking you to select whether the engine is a two or four stroke.  There's a dedicated button for this, which like the ignition selector has an indicator built into the button itself.

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Self explanatory really...4 for a four stroke and 2 for a two stroke.

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The number of cylinders is then set using the left of the three buttons below.  These have different functions in different program modes hence having several legends, it's less confusing than it initially looks.

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The selection starts at 0 by default, and pressing the button cycles through 2, 3, 4, 5, 6, 8, 10, 12 then loops back to 2.

The last thing on this section is the timing offset.  This is only needed I believe where the car uses a magnetic pickup to fire the ignition, this is usually offset a few degrees before or after TDC.  You need to dial this in here.

Pressing "number select" initially changes the sign to + or - to reflect whether the offset is before or after TDC, then "cursor advance" moves to the first digit, with "number select" used to advance the number.  This process is repeated until you've dialled in the correct offset.

The screen below is an example which would have been used on my old Saab from memory, you can see the cursor showing which digit is being entered.

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Once you have advanced to the last digit it will tell you to press # to the next page.  It won't let you proceed if there are things you've missed.

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This then brings you up to the "Cranking/Pinpoint Tests" page.

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This gives you quite a bit of information on what's going on.  However this is only half the information it can show you.  An additional page is accessible using the "short" button on the control panel.  This appears to indicate "short-cut" rather than that it shorts anything out to kill the ignition system or anything.

Here it's shown pressed, hence the vivid orange indicator shown.

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All of the buttons - even those which are purely momentary - have the indicators in them.  Utterly unnecessary, but a nice touch.

This screen gives you some really quite clever diagnostic information.

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This shows you the difference in engine speed, starter motor current draw as the engine spins over each cylinder.  This can be helpful in showing if one or more cylinders has a significantly lower compression ratio than the others. 

You might need to actually stop the engine from starting to get solid data from this test, and there's a control to disable the ignition system labelled as "engine kill."

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Pressing this toggles the kill, and when it's enabled a flashing "engine kill" warning is shown on the display to warn the user.  Having this feature on hand is obviously useful from a safety perspective as well.

The "Short" button latches, so pressing it again will drop you back to the Cranking/pinpoint Tests page.

Once you're done with that, pressing # will advance you to the main running test page.

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This shows you pretty much everything you need to know.  The displays look to update pretty rapidly, at least a few times a second.  If wanted, you can pause the data on screen with the "Display Hold" button.  This is directly below the # button.

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When this is enabled a "hold" message flashes at the upper right of the screen to warn the user that live data isn't being shown.

A useful feature of this as well is that in the main screen above, when the display hold control is released, the original data is left in the screen with a new column being put up for the live data.  This allows you two "old" readings to be shown along with the live data.  This could be really useful if you're making small tweaks and wanting to double check what effect it's had.

The below display shows a "full" page with two columns of held data shown.

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The live data is always shown on the leftmost column.

That's as far into the running of this unit as I've gone...but it gives you a basic rundown of how the computer works.  Shows how it does a pretty good job of guiding you through everything...which in the mid 80s really wasn't a given!

Probably the most daunting looking controls relate to the scope...though I've never really done enough work with that to be able to talk through it from memory.

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The Short button being grouped here rather than with the computer controls is just to keep you on your toes.

I'll try someday to write a bit of a how to for this too...I'll need to learn to drive it a bit better first though. 

Likewise some of the advanced features of the computer...there's a whole additional layer in there I think.

For the sake of convenience there's a remote control which duplicates a number of buttons from the front panel to make life easier for the technician.  #, Display Hold, Short and Engine Kill being those controls.

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The "Print" button would trigger the optional printer.  No timestamps or anything, it would just literally print a copy of what's shown on the screen.  Sadly I don't have the printer, though I do have the interface card (found in the base cabinet) should I ever come across one.

 

Probably horribly tedious to most of you, but hopefully it's vaguely interesting to you if you're into old tech and want to see what would be happening when you're blindly mashing buttons to see what makes it tick.

Any questions, let me know.

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7 minutes ago, Zelandeth said:

Probably horribly tedious to most of you, but hopefully it's vaguely interesting to you if you're into old tech and want to see what would be happening when you're blindly mashing buttons to see what makes it tick.

Tedious?! It's made my Friday night...beats the Graham Norton show or whatever is on the TV. Thanks for the photos and the detail :-)

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I enjoyed reading the detailed write up very much as well :) 

its interesting to hear it only goes down to 2 cylinders, Poor @egg cant have his Mk12 diagnosed/tested by it! 

unless that would be done using the "0" cylinder setting?

also im curious how would/could a rotary engined car be hooked up to it? or what about a wasted spark ignition system like in a 2CV?

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13 minutes ago, timolloyd said:

I’m really enjoying this, thank you. Keep up the good work!

 

13 minutes ago, mat_the_cat said:

Tedious?! It's made my Friday night...beats the Graham Norton show or whatever is on the TV. Thanks for the photos and the detail :-)

Thanks folks, nice to know I'm not being totally boring!  I just can't quite get my head past what a pleasing thing it just is.  You just don't get industrial equipment with this sort of visual flair these days.

Really do need to clean the control panel and the buttons though.  The inside of the buttons is quite dusty too...so I suspect that getting those properly clean may involve quite a bit of work.

On the plus side, the matching mechanism is on the upper surface of the casings, so I should be able to get the ones which are currently sticking to cut it out and behave themselves without too much hassle.

I'll need to see what I can do about the paintwork on the case... there's surface rust speckling quite a lot of it, so a respray is probably the only long term solution...suspect that's a few years down the line though!

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4 minutes ago, Zelandeth said:

Thanks folks, nice to know I'm not being totally boring!

It almost certainly is to the average person in the street, but to a small subset of the population (possibly in a majority on this forum) it's just ace! I completely get you with the old tech thing - before everything got cheapened down to 'just good enough'.

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Because I'm me and find them far more interesting than I probably should, here are a couple of additional photos of the ridiculously overcomplicated status indicators built into the buttons.

It surprises me that they went to the lengths of building them into even just the momentary controls.  You never actually *see* this one as the control is actually latched on software...the orange announciator in the button is normally hidden by your finger.

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The actual indicator that this is active is a message that flashes at the lower right hand corner of the screen.

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There is apparently a volts/ohms measurement capacity in there somewhere (which I've yet to figure out how to access), which is switched between the two modes using this control.  Here it is in volts mode...

IMG-20191123-181448.jpg

 

...and ohms mode.

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Just surprises me this wasn't just done either on screen or using a status LED next to the control.  I remember looking at this sort of control when I was building a power supply a few years back, and these things were *expensive* - even basic ones without legends like this.  "We spared no expense" seems to be a running theme with this machine.

I've got a slightly more sane (though still offset) temperature reading now I've actually got the thermocouple plugged into it rather than a hall effect sensor!

I wanted to have a look at all the analogue cards to check for any additional socketed components, dirty contacts or dry joints.

Started out with the volts/ohms board as I know there are issues with that subsystem.

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Had a brief "Ah ha!" moment when I spotted that toasty looking resistor...but checking it shows it to measure precisely the value that's stamped on the side of it.  Nothing else obviously amiss.

The next board is the trigger control board.

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This is quite important in that what it does is essentially listen for the ignition pulse firing on cylinder number 1, as that is the timing reference to which everything on the machine is slaved.  Nothing amiss here that I can see.

Unsurprisingly, the next board along from that is the main timing board - this basically keeps everything in sync with the signal tracked by the trigger control board.

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One of the more densely packed boards.

I initially thought that the next board (labelled "AMP" on the card cage) was going to handle a lot of signal amplification...but it actually appears to be the signal processing for the amps and temperature sensors.

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This board does have a couple of dry joints that I'll give a tickle with the soldering iron tomorrow.

"CAL" is the next one, which I'm assuming given the precense of several relays, physically connects loads of known values across the inputs to undertake the calibration self test.

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Again some of the soldering isn't great looking, but I couldn't actually see any dry joints...I may well reflow some of the heavier connections though as they could be better.

The fact that the only systems which are consistently failing the self calibration are the HC and CO meters is one of the reasons I want to have a really good look at the wiring from the I/O backplane to the sockets at the end of the boom.  

Speaking of I/O, that's what the next board is tasked with dealing with.

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Nothing wrong with this one that I could see.

Next up is the vertical pre-amplifier board, I believe this relates to the scope.

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Quite obvious from the lovely old school hand routed traces that this one and the trigger control board are quite a bit older in design to the majority, though the date codes show they were actually made at the same time as the others.

"Logic Board No. 2" is next...though I don't recall seeing a number 1 anywhere!

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I'm guessing a bit, but based on the hardware present that this is just handling some low level buffering or such like they didn't have room for in the main computer cage.

No signs of trouble anyway.

Finally we have an identical pair of cards containing quite beefy deflection amplifiers to drive the CRT (one card handles horizontal, the other vertical).

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All of these boards could do with a good clean, as do the digital boards (which I'll grab proper photos of soon too) due to the close proximity of the cooling fan.  Shame Sun didn't feel it worthwhile to fit a filter to it.

So nothing nothing obviously amiss there, aside from one resistor which has got a bit warm at some point and one capacitor on the amp/temp board that's got dry joints.  I really did want to get them all out for a proper check over though.  No socketed ICs or anything like that (which was responsible for the original display issue) in need of attention, but it was worth checking.

Looks like I might actually get a few hours free tomorrow afternoon, if so I'll hopefully get a bit more stuck into trying to work out what's going on with the faults.  

The biggest irritation there really is that there don't seem to be many labelled test points, which would make checking to see if all the power supply rails are present and correct (there are a load of them!) a lot easier.  Obviously given the card based construction it's a bit tricky to probe a lot of the machine when it's running as the cards are quite tightly packed together.

The other thing I wanted to check these cards for was whether they were hiding any more tantalum capacitors like I've seen on at least one or two of the digital boards, as once I've ascertained how many of them there are they will be getting replaced on mass.  Wouldn't surprise me if that alone sorted a lot of the issues based on prior experience.

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very neat stuff!

id still be a bit weary of that toasty looking resistor, and would look at replacing it,

it might measure fine when cold, but I could see its value drifting/changing as it warms up given how sad it looks

(plus knowing my luck, id have everything working, and just as I get it all buttoned up that resistor would actually fail on me!)

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4 hours ago, LightBulbFun said:

very neat stuff!

id still be a bit weary of that toasty looking resistor, and would look at replacing it,

it might measure fine when cold, but I could see its value drifting/changing as it warms up given how sad it looks

(plus knowing my luck, id have everything working, and just as I get it all buttoned up that resistor would actually fail on me!)

Access really isn't an issue on this thing.  Getting access to the computer takes about 90 seconds.  Maybe double that to get the full height digital cards out. 

It is a somewhat high power resistor, so I'm not discounting the discolouration as just being the results of 30+ years of use.  Not that unusual to see things like that in televisions from this era.  As I think I do have a suitable replacement in stock though I will probably look to get it swapped out though once we've got any suspect caps changed.

Does make me wish I had a set of schematics though so I could see what it's doing.  It's a bit tricky to reverse engineer as a lot of connections just disappear into the backplane connectors and off to goodness only knows where.

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Today was the day to get all the digital cards out for a check over and to get everything reseated.

So here are the digital boards, from left to right.

"CRT" - This is responsible for taking the data from the computer and converting it into a composite video signal which is fed to the monitor.  

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"MUX" - Handles all the analogue to digital conversion, signal processing and such like.  Initially I thought "oh my god bodge wires" when I saw this, before realising those wires are all shielded coax, so they have just decided it's a more reliable way of getting a clean signal across the board than using PCB traces.  Even if it does look a bit shonky.

IMG-20191124-163943.jpg

The whole machine is astonishingly free of bodge wires actually...especially for a design from the late 70s where they usually would find *something* after the board's had gone to be made...

Lovely white ceramic package on the ADC.

"I/O" - No great surprise, does most of the heavy lifting with regards to the actual I/O side of things.

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"CPU" - Unsurprisingly, contains the CPU and the 64kB of RAM it makes use of.

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"MEM1" - Basically all the ROM.  Interesting to see that while these initially all look to be EPROMS, they're not.  While there are some, there are also a shedload of character generators.  My guess is they're using this to give greater control over the display without going to the lengths of full bitmap control.

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"PP" - Pre-Processor.  Not actually entirely sure what this does, though I have to assume basically just does some general housekeeping which we would normally expect to be handled directly by the CPU these days... purely a guess though.

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The EPROM here was losing its label, so a bit of black tape was applied to help keep the data safe.  

Probably the main reason I would love to find an actual service manual for this (VERY unlikely as Sun kept really quite tight control over) is that it would probably give me a really good breakdown of the actual system architecture - sadly there's a lot of hardware in here I've never worked with before, so there's a learning process involved.

All of the socketed components on these boards were reseated while I had them out, as I knew this had already sorted one problem.

Turns out that while it's not fixed everything (the gas analyser is still failing the self test), it has definitely helped.  Previously we had complete nonsense shown on the voltage readout.  Now however we seem to have sensible data shown.

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The column on the right is showing the data from when I had a car battery connected to the voltage measurement lead, the one on the left is with the leads shorted together.  Had to do that as it's smart enough to know when there's nothing connected and will just blank the display for that measurement.  Helpful in the real world...but slightly awkward during testing!

Not worrying too much about a 0.2V offset at zero for an instrument of this type, the reading with a load connected was spot on...multimeter was showing 12.23V.

Worth noting that we appear to have more sane readings on the vacuum gauge as well now, that was tending to wander around quite a bit at rest too.

Definitely progress.

Know this is repeating myself to some folks I've spoken to about this, but I figure it's worth mentioning one of my plans for this thing long term to the world at large.  One of the useful things about the monitor the computer is that it's simply a self-contained composite unit.  The signal from the computer to it is simply carried by a twisted pair of wires.  So it would be a truly trivial task to cut into that and introduce a switchable video source.

My intention here is to fit a small self contained computer (probably a Raspberry Pi because I know I can just throw Debian at it rather than having to muck around with it) somewhere in the case.  This would then allow me to use the monitor there to view manuals, data sheets, instructional videos etc in the garage on something a bit more user friendly than a tiny phone screen.  It's a really nice sharp screen so should do just fine.

I'll do doing nothing which cannot be reversed easily.  The only thing I'll need to fit to the outside of the case will be a switch to change video sources.  Luckily I won't even need to drill a hole for that as there's a convenient rubber bung by the remote control input for an option port...so I can just put a hole into that rubber bung rather than drilling a hole in the actual case.

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Just seems a really nice way to bring it functionally into the 21st century somewhat to help it perform the sort of tasks it was originally designed for.  Quite often I find myself in the garage with a wiring diagram of something open on my phone and getting really fed up with the screen turning off every five seconds...so having a fixed screen which I can't drop under the car will be most appreciated.

So that's what will be getting done to improve it in addition to the actual service and repair work.

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I believe this is the point where I should cue the mad scientist manic laughter...

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Actually an order of magnitude clearer in person...my camera (unsurprisingly) isn't fond of taking pictures of an interlaced CRT display.

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17 minutes ago, Zelandeth said:

I believe this is the point where I should cue the mad scientist manic laughter...

IMG_20191125_222203.thumb.jpg.86847e62b84208d473fc948a3da18763.jpg

Actually an order of magnitude clearer in person...my camera (unsurprisingly) isn't fond of taking pictures of an interlaced CRT display.

haha awesome :) 

its like that little black and white TV you have setup, but on another scale entirely :) 

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I wound up out in the garage earlier this evening digging some rubbish out the chest freezer at the back and when done figured it was about time I gave TPA a bit of a run.

I then figured I may as well set the camera recording...so have a fifteen minute ramble with bits of Invacar involved.

Apologies for it all being in portrait...I realised I'd done that after about five minutes and couldn't be bothered starting over. (You can't change it while recording...and I didn't want to have to faff around editing videos together for what was meant to be a quick ramble!).  Will make a point of getting that right next time.  Oh...and setting notifications to silent so the phone doesn't buzz at me while video is being recorded on it.

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7 hours ago, Zelandeth said:

I wound up out in the garage earlier this evening digging some rubbish out the chest freezer at the back and when done figured it was about time I gave TPA a bit of a run.

I then figured I may as well set the camera recording...so have a fifteen minute ramble with bits of Invacar involved.

Apologies for it all being in portrait...I realised I'd done that after about five minutes and couldn't be bothered starting over. (You can't change it while recording...and I didn't want to have to faff around editing videos together for what was meant to be a quick ramble!).  Will make a point of getting that right next time.  Oh...and setting notifications to silent so the phone doesn't buzz at me while video is being recorded on it.

I enjoyed the video very much :)  (apart from the fact its in portrait but you know that already)

nice to see TPA getting an engine run at least!, I wonder if it would be worth propping her up on stands, and then putting it into gear to give the pulleys a run, so the surfaces stay clean etc?

as for car phone mounts, have you tried talking to @dollywobbler about the kit he uses? given recording video in cars is literally his job at this point and he also has a Model 70 :)

(Btw to the previous post, whats the rez its running at? looks like 1024x768? looks surprisingly clear for composite video, but then again its only BW not colour)

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I'm not too worried about issues with the drive at the moment.  She's stored in a very dry well ventilated and reasonably warm garage so corrosion should not be an issue really.

Good question on the resolution.  Had to poke it over the network (that system doesn't usually even have a display attached) to check, but it defaults to 1024*768 so that's the most likely option.

The display is really surprisingly clear - and will be more so once I lock the thing into a greyscale colour mode as if should get rid of the noise on the image due to the colour content.  Don't imagine locking the RPi into a greyscale mode is hard.

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15 minutes ago, Zelandeth said:

I'm not too worried about issues with the drive at the moment.  She's stored in a very dry well ventilated and reasonably warm garage so corrosion should not be an issue really.

Good question on the resolution.  Had to poke it over the network (that system doesn't usually even have a display attached) to check, but it defaults to 1024*768 so that's the most likely option.

The display is really surprisingly clear - and will be more so once I lock the thing into a greyscale colour mode as if should get rid of the noise on the image due to the colour content.  Don't imagine locking the RPi into a greyscale mode is hard.

 

cool :) (I was wondering about the colour composite into a BW monitor/TV thing, I do remember you would get noise when doing that, but I could not recall if it was just with RF or also composite)

I was wondering, is it possible to make it so you can have the monitor turned on without having to turn on the rest of the system?

(for example if your working on something and you only just have to quickly pull up a PDF or something, it would save having to turn on the rest of the system unnecessarily)

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1 hour ago, LightBulbFun said:

 

cool :) (I was wondering about the colour composite into a BW monitor/TV thing, I do remember you would get noise when doing that, but I could not recall if it was just with RF or also composite)

I was wondering, is it possible to make it so you can have the monitor turned on without having to turn on the rest of the system?

(for example if your working on something and you only just have to quickly pull up a PDF or something, it would save having to turn on the rest of the system unnecessarily)

You will pretty much always get some "dot crawl" artifacts on a B&W display being fed a colour video signal unless there is specific circuitry in there to remove it.  It's just down to how the chroma data is embedded in the signal.

Most B&W televisions etc this is completely irrelevant as the display isn't usually sharp enough for the effect to be all that noticeable, especially from normal viewing distances.  This display however is a *bit* sharper than your average TV.

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So the effect is quite visible - though more so here as you're looking at 100% saturation colour bars than in normal use.  If you just feed in greyscale video, the issue is invisible.

That above image though gives a better indication as the actual sharpness of the CRT (no idea what resolution that is - that's just what the HDMI to composite adapter outputs when it is powered up with no video input present).

I could probably make it so that the monitor could be powered up independently, though it would involve a moderate amount of work.  The power feed to it appears to be run from the computer itself rather than just a mains lead running obviously from the mains switch, so I'd need to do a moderate amount of work to chase that back to its source, so at the moment that's sort of listed under "stuff it might be nice to look into someday."

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ah yes dot crawl that's the term i was looking for :) 

and I feared such on the monitor, reminds me of bringing up the CRT in AIO Macintoshes (iMac G3s eMacs etc) independently of the logic board so you could feed your own signal into them

 

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Sometimes you're winning, sometime you're not.

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Was last running a few days ago.

Battery fitted less than a year ago.

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Better not be a failing alternator.  Given the amount of money the car is about to have spent on it, that would probably be the straw to break the camel's back...especially as it will be an absolute swine to fit, being buried under the hydraulic pump.

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I don't understand the deeper tech stuff of the Sun tester but it's a really interesting write up. I've used similar machines in the past and it's enlightening to learn more about them.

Have you found out how much it would have been new? These kind of things were usually bought on the tick I think, as a result of being very expensive.

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