Zel's Fleet Blog - BX, Jag XJ-S, Sinclair C5, Mercedes 208D & 230TE, AC Model 70.

[CitroJim]

Zel, I'm enjoying your blog posts immensely so keep 'em coming

And those calculator pictures really bring back some memories!

[Zelandeth]

Glad to report that the wipers behaved all day today - save for me having managed to get grease on either the wipers or screen. So a thorough degrease and clean will be happening tomorrow. The blades were just about due a change anyway so it's a good time to just do so anyway. Squeaky or juddery wiper blades are one of those things that are like fingernails down a blackboard for me.

While I've told myself I need to reign things in on the vintage tech front following this last little buying spree I did cave and grab one other item last night because the price was right and it ticked a major box.

Something I've never actually seen in person is the first generation LCD screens. Unlike the TN displays which became commonplace from the late 70s onwards with the usual black digits on a reflective backing, these early DSM LCDs worked very differently. Instead they are clear when off, but when the digits are powered the segments become reflective.

It's a technology which only stuck around very briefly as TN displays were just around the corner and had a plethora of advantages. Near zero power draw, less picky lighting requirements to make the display readable, massively quicker response times and far better long term reliability to name a few.

They're also very prone to failure due to the glass separating, so when I saw one with a perfect display available I grabbed it. This is a Sharp EL-808, which I *think* was the second commercially launched calculator to ever use an LCD panel.

This will be the last one for a while though...well unless anything that's right at the top of the wish list turned up anyway. Though odds of finding a Compucorp 320 Series at sane money are very poor based on previous occasions I've looked.

My computing teacher at secondary school had a 324G Scientist on his desk, which I very much coveted back when I was in that class.

Some info on the machine in question here.

[Zelandeth]

Finally had a package from the US arrive today - which was posted well over a month ago.



This was a very random purchase from a while ago which very much appealed to my inner geek.



These bags contained these bits of hardware. One switch and one indicator.



While these are both from the 80s I believe, the designs haven't really changed hugely since the 60s.

The number of components in this thing for a four way latching switch is absolutely ridiculous.





From an engineering perspective it is simply a thing of beauty and a joy forever.

Now need to figure out something to do with it...Probably a master power switch for my workstation as I can use the split indicator (one side is red, other is green) for something useful then.

Yes, those are the same style as used in the Nasa control rooms from the Apollo era onwards (these are a slightly later style, but very similar). The one labelled Radar Acquisition is actually made by the Master Specialities Company who produced the original Apollo era kit, the unlabelled one is made by Unimax, but they're a very similar setup. Main differences are in the panel mounting method and the exact design of the ratchet used to latch it. The fact is that these were (and possibly still are) used in a plethora of military settings as well so they're pretty easy to find in the US.

I've always been a major Apollo enthusiast, so the moment one of the YouTubers I follow identified what the switchgear in the old MOCR (which everyone calls Mission Control) actually was I was on eBay hunting stuff down within minutes.

The seller I got this pair from has THOUSANDS of mil spec bits of switchgear and instrumentation in their eBay shop - I could quite happily have spent a small fortune in there as it's basically an entire shop full of stuff I WANT. I have precisely zero use for 99.993% of the stuff I'd buy, but that doesn't stop me wanting it! The only thing which saved me from going utterly overboard was that postage costs a small fortune from the US these days. If I'm ever in that area in a future visit to the US though you can absolutely guarantee that probably half my luggage will be full of stuff from that warehouse. I will seriously be like a kid in a sweet shop.

[Hell Razor5543]

How about a RADAR speed trap jammer? When the system is turned on it 'looks' for the frequencies used by the various different speed guns, and if it finds one it first turns on the RADAR Acquisition light, and then either 'jams' that frequency or (to really baffle the operator) bounces back a signal that shows you are 'apparently' travelling at 200MPH! That, in the Invacar, would really cause some confusion!

[Zelandeth]

Nothing huge to report today, but the enclosure I'll be putting the distributor condenser on the Invacar has arrived.



Nothing fancy, it'll do what I need it to just fine though.

I'll probably tuck it away underneath the battery tray in the engine bay so should disappear once it's in place and has got a bit of dust and grime covering it.



Not sure if I mentioned it before, but I really want to install a remote engine start switch in the engine bay. That will likely end up on this enclosure as well which makes it a little less oversized for the job.

Amusing random anecdote from earlier in the day which might give you a giggle. Spotify appear as of the most recent update introduced a bug - at least with my exact hardware/software combination. This means that there appears to be roughly a 20% chance of the volume jumping to 100% the nanosecond I press play.

This is annoying. It's made me jump several times when I've had my headphones on over the last few days. The best (or worst!) by a mile though was this afternoon, when I had it hooked up to my stereo. All 350W RMS of it. Unbeknownst to me the volume on that had been left pretty much all the way up as several of the devices which tend to be hooked up to the aux in have pretty low output levels.

I reckon I must have levitated a good couple of feet in the air, as the speaker I was actually leaning on at the time literally knocked the wind out of me. In addition to me leaving the ground, it felt like pretty much everything else around me did as well. Including the armchair that's a heavy two man lift, the sofa, both dogs and the foundations of the house.

These things pack a mighty punch...120W RMS (each), with integrated subwoofers.



The speaker to the right is one of the Pioneer CS-585s I inherited from my grandfather and will never part with as they still sound fantastic. Really do need to sort the cat damage (which happened in the late 80s!) to the cloth covers though. They're normal classic hi-fi speaker sized and are shown there just to give a sense of size of the Sony ones...which are heavier than they look too.

It's astonishing how long it can take you to find a volume control in a situation like that! Hitting pause was out of the question as when I jumped my phone was launched into low earth orbit (we found it down the back of the sofa after about 15 minutes of searching).

Just about everything in that room that was just leaning against the walls or was loosely stacked (it's a bit of a junk store) ended up on the floor as well. My ears finally stopped ringing after a few hours...

If Spotify could fix that bug I'd really be grateful. Not sure my heart can handle that happening again!

[Zelandeth]

Nothing to report car-wise today thanks to the non-stop rain. Unless nervously watching as the run off from the driveway made it into the garage counts - thankfully only by a few inches.



It wouldn't surprise me if there had originally been a proper drain there and the previous owner of this place decided to bury it with a flower bed. That sounds like the sort of thing they'd do based on other sensible design choices found around the house.

Fair warning...The rest of this post is all vintage tech. If that's not your thing, don't bother reading on. I just don't do quite enough of this to really be worth my splitting of an entirely separate thread elsewhere...Plus I know from prior history that I'll utterly fail to remember to keep more than one thread updated.

The parcel which arrived this morning was the last one I was waiting for - and one I was very curious to take a proper look at.



Didn't spot from the eBay listing that it still had the original slip case, that's always nice to have for something in the collection. So what's in the case?



At a glance it's just a very basic four function calculator, by 1972 when this dates from that really wasn't anything to write home about. What was the standout feature of this example though was the display. This was as far as I'm aware only the second model commercially available which made use of a liquid crystal display. Though it's not quite an LCD as you know it (unless you're into this sort of stuff...though even then I'd not seen one of these in person until this evening).



So it's got the light/dark flipped...what's the big deal?

Oh no...It's much more than that. This is a DSM LCD - or Dynamic Scattering Mode LCD. The Twisted Nematic LCDs you're used to seeing work by changing the way the polarise the light depending on whether a segment is subjected to an electric field or not. These are very, very different. For a start, no polarisers anywhere here. The way these work is that in their rest state they are completely transparent, however when current is passed through a segment here the crystal structure is disturbed so the segment becomes opaque, taking on the appearance of frosted glass.

The way Sharp used this actually to place the display segments in front of a mirror.



The inside of the hood on this calculator is lined with a black felt which is what the mirror behind the display reflects so as to give a good visual contrast.

It's a challenge to photograph clearly! However the display is every bit as clear as it looks in the photos. The really interesting thing is that if you look close enough you can actually see a sort of shimmering effect within the LCD segments due to interference patterns set up within the crystals.

There are far less decent photos of DSM displays out there than I expected, so here's a few. I took something like 75 photos trying to get decent ones actually showing this display in its full glory...They'll have to wait for me to put it on the website.



That's where I've slipped a bit of paper in between the hood and the display so you can see how the digits actually do appear like frost on the mirror rather than anything vaguely resembling the appearance of any other type of display I've ever seen. Nothing looks anything like one of these.



(That one was from before I cleaned it, sorry).





That almost retroreflective like texture on the surface of the digits isn't a camera artefact - it's not static either. The digits do actually shimmer very slightly whenever the display segments are powered. It's quite beautiful to observe through a powerful macro lens.





I'll need to do some experimentation with a macro lens and natural light to see if I can do better.

A video showing some absolutely gorgeous super-macro video of these displays in action can be found here though:



On a completely unrelated note to display technology, which is why I bought this thing...Is it just me, or does this thing seriously look like an Original Series Star Trek tricorder?



The quality of this thing is worlds apart from anything like this nowadays...Absolutely everything about it just *feels* expensive and just oozes quality.

Quite a bit smaller than I thought it was, here's it next to the Kovac which turned up a week or so back.



Yeah, this one is going to be staying on the desk full time I think.

That pretty much gives me *nearly* full coverage on display technology now I think...

[] Nixie: Check. Fine, it's a benchtop multimeter, but Nixie calculators are EXPENSIVE.

[] Panaplax: Nearly...The Kovac has a segmented neon display which is nearly there. The only calculator I'm actively looking for just now does have a Panaplax display though. Compucorp 324G or similar if you happen to have one floating around...

[] EL: No...Though I don't *think* anything as small as a calculator has ever used an EL display. They were more of a competitor to plasma displays in the early days of laptops I think.

[] LCD: All three generations, check.

Only missing the really exotic ones like edge lit incandescent or single plane projection (Don't think numitrons were ever used in calculators?)...Still have my eye on getting a proper flipdot display at some point to, but that's nothing whatsoever to do with vintage technology really, I just want one!

Oh...Or CRT. A Friden EC-130 or 132 would be sort of the "unicorn" find for me. I seem to recall making strange squeaking noises when I spotted one in the National Museum of Computing. Odds of ever finding one: Slim to zero. Odds of finding one for sale at a price I can justify paying: Probably less than zero.

Hopefully I might actually be able to get back into the garage at some point in the next couple of days if the rain ever stops!

[CitroJim]

Love that calculator Zel The display is quite magical!

I found my very first calculator... Bought in 1974 after saving up my pocket money for ages for it... I can even remember how much it cost... £24.75

In those days that was a serious amount of money...

From Dixons I think...

Sadly, it no longer appears to work...

[Hell Razor5543]

Love that calculator Zel The display is quite magical!

I found my very first calculator... Bought in 1974 after saving up my pocket money for ages for it... I can even remember how much it cost... £24.75

In those days that was a serious amount of money...



Sadly, it no longer appears to work...

...Until Zel got his hands on it, that is!

[Zelandeth]

Love that calculator Zel The display is quite magical!

I found my very first calculator... Bought in 1974 after saving up my pocket money for ages for it... I can even remember how much it cost... £24.75

In those days that was a serious amount of money...



Sadly, it no longer appears to work...

Not seen anything outside my house with that name on in a while! I've a set of their headphones here probably from a similar era. Until I got the current wireless set five years or so back they were still in daily use.

Prinzsound Headphones

Love the thick clear reverse marked buttons. That's an aesthetic which I wish hadn't all but disappeared these days.

Don't imagine there's a huge amount in there, by that period they were generally just based around a single chip (as modelled by the TI-1250 below) and a handful of passives. As such they tend to be pretty bombproof. Dirty switch contacts or a break in the wiring to the battery holder (I'm assuming this uses a PP3 on flying leads like most did) have to be by far the most likely issues.

[CitroJim]

My Prinztronic uses 4 AAA batteries as its very slim and there would be no room for a PP3 battery! All the problem turned out to be with it was a bad contact on the sliding switch

Not bad that a 45 year old calculator still works I find the 'Bubble' LED display on it as magical now as when I first got it...

What I'd like now is an LED watch from the period that uses the same display... I remember my old Sinclair Scientific calculator used a bubble display with a nice purple tint to it...

Speaking of the Sinclair Scientific, I was intrigued to learn how they did it 'on the cheap' using a standard 4 function chip in a very clever and devious way... It explained why some (most) of its functions were inaccurate at extreme range, especially tangents!

[Hell Razor5543]

What I'd like now is an LED watch from the period that uses the same display... I remember my old Sinclair Scientific calculator used a bubble display with a nice purple tint to it...

I wonder if one of the watches in these lots might be of interest, Jim?

https://www.ebay.co.uk/itm/Mens-Job-lot ... Sw6DBf3ysI
https://www.ebay.co.uk/itm/Mens-Job-lot ... SwcRlf3y3a
https://www.ebay.co.uk/itm/Mens-Job-lot ... SwHK1f3y82

[CitroJim]

What I'd like now is an LED watch from the period that uses the same display... I remember my old Sinclair Scientific calculator used a bubble display with a nice purple tint to it...

I wonder if one of the watches in these lots might be of interest, Jim?

https://www.ebay.co.uk/itm/Mens-Job-lot ... Sw6DBf3ysI
https://www.ebay.co.uk/itm/Mens-Job-lot ... SwcRlf3y3a
https://www.ebay.co.uk/itm/Mens-Job-lot ... SwHK1f3y82

Wow! Thank you James

[Hell Razor5543]

I just searched on ebay for Vintage LED Watches. There were a lot of them, but I 'grabbed' those three listings for you to peruse.

[CitroJim]

I just searched on ebay for Vintage LED Watches. There were a lot of them, but I 'grabbed' those three listings for you to peruse.

James, it is hugely appreciated Looking at those listings brought back some good memories!

Happy to report my old calculator works

Still good after 45 years...

Just bad battery contacts...

[Zelandeth]

Reckon we need some nice oblique angle photos of the keypad on that calculator, Jim...

Someone was enjoying this afternoon...



Getting to destroy the wrapping paper is pretty much his favourite thing in the world.





The main box waiting under the tree for me this year - completely unexpectedly - contained this.



This contains a 3D printer.

Immediate reaction "Oh god...this means I need to learn how to drive Blender!" Which is a bit of software I've generally run in terror from on all previous encounters!

Would have been nice to get to set up the 3D printer this evening wouldn't it?

Life had other ideas though. Before we'd even tidied up from dinner it became immediately apparent something was amiss with the fridge. It was 15C and the lower veg drawer was stuck in place by a block of frost at the back.

Fine...everything out and start pulling it to bits.



Became immediately apparent we had a defrost issue - not least because the lower moulding there (which is the airflow duct covering the evaporator) was completely frozen in place.

As it was clearly stuck to the evaporator I couldn't be too rough with it - but eventually I got it free.

That fan hasn't been doing anything for a while...



Yes...definitely looks like the defrost heater has died. The inch and a half deep block of ice immediately below the heating element tends to suggest it's not been doing much. For those not familiar with the innards of refrigeration equipment, he heater is the black thing below the silver coils.



Also...the bits of a fridge you can't get to to clean become utterly disgusting.

After some attention with a hairdryer I got the fan freed from the ice cube it had turned into and it seems to have survived. I chiselled the block out of the condensate drain tray, blasted the drain clear (no idea if it was clogged before it froze up or not), and reassembled everything.

Sadly this fridge is intelligent enough to know if anything is unplugged so will just throw error codes if you try to power it up in bits...so I had to put it all back together before I could test things.



I also had to dismantle the door hinge to find and defeat the switch so I could ascertain whether the fan was working...as it only runs when the door is closed.



Fan is running, cool air is being circulated...good. Everything can go back in.

I'll need to investigate why the defrost heater isn't working but that can wait until tomorrow. I can easily test whether voltage is being supplied to the circuit from the main control PCB.



I've done work on this board before as the relay that controls the compressor burnt up a year or two ago. Was pretty painless really.

Credit where it's due to Samsung, by the standards of modern white goods this thing isn't bad from a service perspective. Everything is held together by normal Philips head screws (all of which are identical) with no daft clips, and even the pin headers in the control unit are labelled. It's also 18 years old so isn't doing bad to be honest! Especially given the abuse the kit in this house took before we moved in...The dishwasher for one was scrap! I do question why such control circuitry is needed for a fridge freezer though!

Given the freezer seems to be working normally my money is on a dead heater element, in which case it should be a pretty simple fix. Which is appreciated as American style side by side fridge freezers are extremely expensive!

Seriously though...Christmas day?!?