Well.... look what's on my bench today ?
I always wanted one so badly, a Tek 575 hollow state transistor/curve tracer !
... but too rare over here, and always 500 Euros "as is take it or leave it, don't ask pics or questions, untested", so not for me.
But perseverance finally paid off ! 3 days ago one popped up ! and advertised at only 100 Euros on top of that, ie a MASSIVE BARGAIN !!!!
Ad did sport a "Make me an offer "button. So I clicked on that and offered well, the 100 Euros he was asking for. 30 seconds later I gave it a second thought and cancelled my offer, to make another one... 150 ! I saw the ad very late, 3 hours after it was published. That's an eternity. It was obvious by that time the seller had already been bombarded with 20 people wanting it, each offering more than the asking price hoping to get it. So I figured if I want even a slight chance of getting a response from the seller, even if negative.... would be to offer him more than the 100 Euros he asked, and offer sufficiently more that it might attract his attention and possibly, though unlikely, make me the highest "bidder". I also gave him my phone number.
5 minutes later he calls me saying OK deal done. Got bombarded with 20 people, they offered me more than the 100 I asked, but your offer is the best, so deal done !
We chatted a bit, cool guy, he was happy his Tek would go to a loving home rather than to a tube hoarder that would dump the dead corpse in the nearest junk yard as soon as he would be done extracting all the tubes from it...
2 days later I visit the guy, in the middle of nowhere. I mean, really the French definition of it : city of "Bourges" in the center of the country, very rural area. Worse than that... actually 50 kms north-east of the city, in as rural and deserted area as you can come up with. Google Maps could not even find his place (it would tell me I had to go in the middle of wine yard...). When I arrived at the nearest most plausible location I could come up with... tried to give him a call so he could give me direction to pinpoint his house... but alas phone said "Sorry Bob, NO SERVICE AVAILABLE" That's my luck ! Lost and unable to phone him, I am screwed !
Had to walk half a mile to get a semblance of signal, a thin slice of network.... just enough that the phone accepted to dial the number... saved. guy came to pick me up. His house was not even visible when you are 50 meters from it, it's hidden by lots of trees, you just can't see it, at all.
Anyway. cool guy. Almost retired, electronic teacher at university in Rouen city north of France. His house in Bourges is just a secondary/leisure house to relax away from human kind and most forms of life.
I was appalled when he confessed having thrown away old tube Tek stuff by the DOZEN decades ago ! The uni he worked at in the '80's was filled with hollow state Tek stuff, that was gathering dust/obsoleted. He picked them up all for free by the truck load, kept a few dumped the rest because it was too many and worth nothing, back then it was considered by all as pieces of junk no one wanted.
Very recently he sold no less than 15 old classic Tek scopes ! Argh I am late !
He kept only one for himself, the one he preferred : a 585A. Have one too but his is in mint condition and comes with a cool blue phosphor CRT and a very unusual graticule I have never seen. Special purpose graticule for God knows what application. I have seen the graticule for Video signal monitoring, there is special purpose Tek scope for that... but his was not like that, different still. Wish I had my camera so I could take a pic to show you. vertically it is short, maybe 2 or 3 major divisions. Horizontally is spans all thje screen or so, and is highly non-linear. Have not slightest clue about it, neither did the guy...
Anyway, guy used his 575 curve tracer decades ago, but stopped using it like 10/15 years ago (still working at the time). He kept it in his lab/house, so warm and dry, great
Over the phone he said he tried to power it up when he put it up for sale, but that nothing would come up on the screen. so I was a bit worried that maybe, potentially, after 10+ years sitting, filter caps might have shorted and as I understand it it could cause the rectifier tubes to die and worse the unobtainium main transformer to go with it... so still a bit worried. Was praying though that maybe the fuse would have blown before the transformer did...
Yesterday, a couple days later then, I drove to his house in Bourges, 450+ kms away...
He went to power it up for me. I thought OK he already tried it so if it wanted to blow, it would already have done so, so no big risk there. Plus... he actually powered it through a Variac to bring the voltage up progressively, in case a disaster might happen..how thoughtful !
He flicked the power switch on the Tek then said : " it only displays a spot and that's it ... ".
Hey ! " a spot "... that's A LOT better and more reassuring than "NOTHING on the display " ! At least it means the CRT and main transformer are probably OK, or not totally dead at least, it's what matters most !
Then a spot appeared, and it even drew a little squiggly line on the screen !
Looked like a little triangle or something...
but was bright and sharp and stable/rock solid, so was happy !
Guy had still a few "Tek bits : a whole stack of 500 plugins... like, I don't know... like too many to count ! Something like 40/50, probably. Even had a cool 1L5 spectrum analyzer plugin !
Pristine inside out.
Also has a special plugin in his 585A, the one that generates a fast rising pulse to help calibrate the scope. A single letter plugin, D T K R I can't remember which Letter plugin it was. would love to have that...
He said in his main house In Rouen he still has some Tek stuff not yet sold or scrapped... said he would take pics and inventory what's left, in case something might interest me. Oh, and he said he would GIVE me a type 81 adapter plugin for my 585, so I can use 500 plugins with it. He has two of these plugins so has no use for the second one. How kind is that ?!
Great because I do not have the adapter plugin for my 585A...
Anyway, took the beasty home with me. Arrived home at almost midnight. Too tired to anything so waited until today to take pics and open it up and give it a test ride... See below.
I grabbed the first tranny I could find, TO92 package, BC something, and stuffed it in the test jig at the bottom.
Played with all the knobs semi-randomly and eventually I could get it do display a nice set of curves, YEAH !!! IT WORKS !!!
The most important controls appear to work : can vary collector voltage, scale and move around the graph, vary the number of steps, change polarity / PNP / NPN...
CRT bright and sharp, stable... the beast basically works, nothing major wrong with it !
Of course I will have to RTFM to give it a comprehensive test, assess every feature, caliber, knob and switch, so of course there might still be some trouble shooting ahead, but whatever it is, it's gonna be minor. All the fundamentals of the beast are good !
So most of the work on this beast is going to be TLC and cosmetic restoration. It's not exactly in concours condition, though nothing majorly wrong with it either. Goal is to not just clean it, no... this one needs, and deserve, some more in depth restoration.
The thing is, guy had actually TWO of these beasts, decades ago. Both defective. With two, he made a good one. Of course he long discarded the donor unit...
So it's a bit of a Frankenstein unit. inside, 80% of it is in great shape, will clean up just fine, but 20% is a little more crusty. Nothing major, but needs some love.
Blue panels might benefit from a respray, will have to get some paint custom mixed, and get a little spray gun. Never done it.
I want to see how good I can make it look, experiment with restoration techniques... and later apply what works, to all my 500 scopes...
The eagle eyed amongst you will already have spotted the two main things wrong at the front :
- CRT bezel mounting studs : one of the 4 is missing. No big deal, surely a standard part I can salvage from one of my 500 scopes.
- Big knob for the " Series Resistor " selection : clearly not original. It's the correct style and size, but not the correct model : it's dark grey rather than black, and it's got a hole in the center, as if there was a little red know supposed to go on top of it.
But again not a problem. I checked on my 500 scopes. That knob is a standard one. It's used in all my scopes as the voltage selector for the probe calibrator. So I can just salvage one.
Then the next main thing I need to do, is to look after all the toggle switches and push-buttons. See example pics below. The threaded part of the switches, along with the retaining nut and washer, are very crusty and rusty. Looks horrible. so I need to take the face plate out, remove all those switches, clean them as best I can, then try and find some company that can redo the plating on them, so they are shiny again. Or maybe one can do it at home ? I see some on Youtube videos of people doing some DIY electro-plating with an old computer ATX power supply... but then you would have to be able to source the required chemicals, and have a way to control the thickness of the plating so it's not too thin an wears out rapidly then you have to do it all over again... I would rather give it to some specialized company. Doesn't even have to be local, seeing as the parts are so small and light, I guess I could just post them to wherever...
What else.....
- It's a very ealry unit I think : SN 007839 . But the dead give away of it's age is the fact that... it uses Selenium rectifiers ! So must be early to mid '50's. By the late '50's all my scopes all had moved away from Selenium.
- The two carry handles at the top of the cabinet are the real leather kind (another clue of its age...), not the fake plasticky rubbery one that some of my other classic Teks have. Normally the real leather handle dry out and literally turn in to dust and disintegrate... even have a scope with ZERO leather, only the inner metal reinforcement is left ! Well, on this 575 both leather handles are in surprisingly good shape !
Bright work of course needs replating, but leather itself is fine. Leather care products will be enough to make it like new again.
- There is a cool metal plate riveted to the top of the cabinet, featuring a table and a graph and some instructions...
- Little spool of silver solder still inside the scope
- Power cord : a modern cord has been hard wired, for practicality, but the original American socket has been retained so it still looks pretty original at the back
The trip cost me about 150 Euros (half ethanol to feed the thirsty Safrane, and half motorway tolls ), same as the 575, but who cares.. I can just pretend I went to visit family or something, or went away to visit something during summer vacation..
Overall I am over the moon. Can't believe I managed to grab one of these, and for only 150 Euros, and a working unit at that.
Plan is to make it look as good possible and give it a full time spot in the lab, so I can admire it all day long and have it handy to actually give it some use whenever I can
I will try to find a Tek cart to put it on
Pics, then need to cook something for dinner, it's 21:15 already !
Message was pretty long so probably lots of typos, so I apologize in advance if it's a tough read ! I did spend the time to proof-read it once... but usually that's not quite enough...
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