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I haven't started using Kicad yet, however, I do use Eagle.

I'd do the following in Eagle, which you may find reasonable to do in Kicad.

Set the grid to the connector spacing, generally 0.156 or 0.125 or 0.1

Create a connector finger with the edge on a grid.? The spacing between the next grid and the edge of the finger should be the same as measured on a board.

Copy the connector finger.

Paste each connector finger so that it aligns with the grid.

Duplicate this, and change the layer of the duplicate to get the bottom layer.

Change the grid back to the normal value (typically 0.050).

What the python script does is to do a step and repeat that you're doing manually.

Harvey

Awesome that would be great. I am kind of out of my depth on this one. The connectors on the board are

Large connector in the front of the scope - AMP 3-530662-0-8301
Small connector towards the back of the scope - AMP 2-530662-5-8110

So making slow progress

Well, I am glad someone said it. All day I was wondering about diode implants....

Jeff KruthIn a message dated 7/27/2021 7:19:21 PM Eastern Standard Time, rickc@... writes:?Dom,

Diodes are made from many materials, but silicone is not one of them.

a note of correctness: Silicone is a polymer used to make things slippery, as in a lubricant. Some adhesives are also made of silicone compounds.? It is also the filling agent for implants used to enhance or replace? certain body parts.
Silicon, element 14 on the periodic table, is an element that is plentiful here on Earth, and is used for many things, among them semiconductor devices such as transistors and diodes.

--rick chinn

Ke-Fong Line wrote:

My bad, I thought it was a new topic.

No problem, I entirely missed the post as well when I was doing research for building my own TM500 prototyping boards a few months ago.

Oddly, now that I have had the chance to closely examine a couple of my TM500 plug-ins I do not see any evidence of chamfering on the card edge fingers. I only see a wide chamfer on the key slots between contacts #6 and #7, and contacts #17 and #18. The board itself ends with no apparent chamfer at all along the long edge. The boards that I had made, and the after-market extender that I bought on eBay, both have a 45 degree bevel ground along the long edge of the card edge connector.

I wonder if this was a feature of the 5000-series or 7000-series scope interfaces, or if it may have been a feature added to the TM5000 interface.

The most that I can see (with a loupe) is what appears to be a very narrow (maybe 0.1 mm wide, at most) wrapping of the gold card edge plating over the corner of the card edge fingers. If this is indeed a thing (and not just a trick of the light) it could obviously be achieved by pressing on the corner of the PCB where the card edge contacts come to an end. I have yet to try it, but I don't imagine it will take much force at all.

-- Jeff Dutky

Simple mistake on the prototype wiring was the cause of the poor TS pulse
detection previously reported.

Here is what it should look like:


This is basically the TS to TTL conversion circuit from the 7M13 readout
module (correctly wired this time.)

Now we have nice sharp edges, and about 35us from the rising edge of the
blue trace (the logic level output) to set up the current sinks
appropriately, which I think is plenty of time.

I am planning to use SPI port expanders, to reduce the number of I/O pins
required on the microcontroller, and also make the circuit more universal,
so I am planning to use an input pin per timeslot. The 7M13 uses a trick
where it diode ORs TS2-10 together, thus requiring only 2 pins of input,
TS1 to flag start of readout, and all the subsequent timeslots simply
increment a counter, no need for interpolation. However, I am planning to
give each timeslot its own pin, that way the circuit can diagnose missing
timeslots and other issues.

On Tue, Jul 27, 2021 at 4:39 PM Ed Breya via groups.io <edbreya=
[email protected]> wrote:

I think you'll need at least two TS detectors (like maybe the first and
last), so you can figure out the actual running frequency and interpolate
the rest of the slots. In my readout exerciser, it is all inside the
plug-in, and uses all of the TSs for direct coding, so it was
straightforward - except for needing 14 interface signal lines.

Ed

--
Andy

On Tue, Jul 27, 2021 at 7:32 PM Carsten Bormann <cabocabo@...> wrote:

On 2021-07-27, at 19:11, cheater cheater <cheater00social@...> wrote:

Seven - one in the open relay rack in the middle right. But that might
be a vector scope, too, or a distortion meter.

Williams tube.



Grü?e, Carsten

You might be talking about the loose tube in a box at the bottom of
the picture. I mean a rack mounted unit between the two PCs. There are
two scopes and a third thing, in the rack, that also looks like a
scope. A Williams tube device has no front display because the front
of the tube is covered by the read-out plate.

BTW I tried getting in touch off list but haven't heard back :) Would
you mind checking :) thanks

Dom,

Diodes are made from many materials, but silicone is not one of them.

a note of correctness: Silicone is a polymer used to make things slippery, as in a lubricant. Some adhesives are also made of silicone compounds. It is also the filling agent for implants used to enhance or replace certain body parts.
Silicon, element 14 on the periodic table, is an element that is plentiful here on Earth, and is used for many things, among them semiconductor devices such as transistors and diodes.

--rick chinn

If you could check your book I would be interested to know if that picture is actually in it - the copy of it on archive.org does NOT have that picture in it! I suspect there were multiple printings of the book with minor (?) differences in content...
DaveB, NZ

I think you'll need at least two TS detectors (like maybe the first and last), so you can figure out the actual running frequency and interpolate the rest of the slots. In my readout exerciser, it is all inside the plug-in, and uses all of the TSs for direct coding, so it was straightforward - except for needing 14 interface signal lines.

Ed

I'll try and get a schematic into the computer tonight and show you what I
am thinking of.

I wasn't talking about changing the edges of the TS pulses, just my
circuit's response to those intentionally slow edges.
I want to push the bulk of the problem to firmware, so I need to field an
interrupt, figure the timeslot, and set up the correct currents before the
mainframe starts to sample the currents; nothing crazy, but if I can buy
myself more microseconds on the front end of the pulse, things can only be
good for the wider applicability of the circuit.
I couldn't find anything usable in the docs for when the row and column
currents are sampled, but looking at the pulse on a scope the window that
the -15V is valid is quite clear, so I am going to target a decent safety
margin around that.
In some later mainframe designs, it appears that the TS timing can be
shortened by certain responses from the module, so I am trying to be
conservative in my timings.

I also do not know if the readout system is similar/identical in the 5000
series (I see readouts on some 5000 displays, but have not found details of
the implementation, nor do I know how prevalent readouts were on
5000-series.) I would like to see the design easily port over to 5000s if
that is practical, even though I don't own a 5000. If there are simple
changes I can make early to accommodate, so much the better.

On Tue, Jul 27, 2021 at 3:31 PM Ed Breya via groups.io <edbreya=
[email protected]> wrote:

Current mirrors should work fine. I presume you meant to say four PNP
transistors for the DAC and level shifting from ground referenced and +5V
powered TTL/CMOS. I looked at all sorts of schemes back then, and concluded
that the DACs were the way to go for my needs. You can get better
performance from the current mirror if you use transistor arrays. I think a
CA3046 or something in that family has enough NPNs to make two mirrors.

The edges of the TS signals are intentionally very slow, to minimize
interference with the sensitive circuitry - do NOT make them go faster. As
I recall, the readout system makes its decision on the value either in the
middle of the TS, or right at the end, when it begins to turn off. The
internal clocking is not precise in frequency (you actually don't want it
constant), but the relative timing of each event is exact (all digital).

Ed

--
Andy

The term "rolling" is mentioned several replies earlier (in a post by ditter2
on 11 March 2019) it says the following:

My bad, I thought it was a new topic.

Looking at the waveform picture, I see that you're looking at speeding up the response of the TS detector, which is OK. I think I misunderstood that you were considering speeding up the actual TS edges. So, never mind about the edge speed admonition.

Ed

Current mirrors should work fine. I presume you meant to say four PNP transistors for the DAC and level shifting from ground referenced and +5V powered TTL/CMOS. I looked at all sorts of schemes back then, and concluded that the DACs were the way to go for my needs. You can get better performance from the current mirror if you use transistor arrays. I think a CA3046 or something in that family has enough NPNs to make two mirrors.

The edges of the TS signals are intentionally very slow, to minimize interference with the sensitive circuitry - do NOT make them go faster. As I recall, the readout system makes its decision on the value either in the middle of the TS, or right at the end, when it begins to turn off. The internal clocking is not precise in frequency (you actually don't want it constant), but the relative timing of each event is exact (all digital).

Ed

The term "rolling" is mentioned several replies earlier (in a post by ditter2 on 11 March 2019) it says the following:

While the chamfering reduces the likelihood of glass scraping the connector when mating,
the step where the circuit board foil trace mates would still scrape when it mates.
Tek prevented this by “rolling” the chamfered edge of the circuit board. The finished board
after plating is ran through a pair of conical rollers that actually smashes the circuit board
which reduces the thickness of the plated board fingers, allowing them to partially engage
into the connector before beginning to deflect the spring function of the contacts. Thus, there
is no edge scraping on the connector during the mating process. The board edge engages
before it begins to force the contacts open.

Now that I've read it again it sounds like this might be able to be done by hand applying a small amount of force to a steel bar angled from a point of contact with a flat surface and the point of contact with the edge of the connector fingers being "rolled".

I will have to examine some of the my TM500 plug-ins to see if I can measure the difference in thickness achieved by the rolling process. I can't detect any difference with my unaided eye or by touch, but a set of calipers or micrometer may be able to measure it.

-- Jeff Dutky

Thank you, Ken. This mod kit replaces early-production 500-series selenium rectifiers in the LV supply with silicon. There’s nothing for the HV supply; modded scopes continued to use 5642’s.

From: [email protected] [mailto:[email protected]] On Behalf Of Ken Eckert via groups.io
Sent: Tuesday, July 27, 2021 11:44 AM
To: [email protected]
Subject: Re: [TekScopes] 5642 rectifier tubes in a Tek 535: Replace or swap for silicone?

I don't know if this helps, but I have uploaded this mod kit instructions that is applicable to the scope

File name:

Tektronix 040-0395-00 mod kit instructions

I used a caliper to measure several of my plug-ins, and went with my best
estimates based on that, then tested with laser cut non-functional blanks
for fit. I only just got the boards back from fab, and so far, fit and
function seem good.
When I post the eagle files, people can just reuse the dimension layer, but
I will also see about producing a dimensioned drawing for more general use.
Let me see if I can make time for that tonight.

--
Andy

The upside-down black and aluminum cylinders look like British 9-pin loctal tubes, or more correctly, valves. The shorter aluminum ones are likely the famous EF50 <> (also called a VR. 91 or 10E/92b). Most EF50s are red, but I have some military surplus ones that have clear aluminum cans. The longer black ones are likely the Mullard EF55 (also called CV 173). The assemblies in the photo could be parts of an early post-war computer, but due to the lack of triodes are more likely radiation counters or the like.

Due to the moderately recent Tek scopes (475?) and PC clones in the picture, this has to be a vintage restoration project. BTW, I count six Tek scopes in the picture.

- John Atwood

What do you mean "rolling" on the fingers?
Do you mean the notch between 6A/B and 7A/B?

I'll probably create a project page somewhere with the eagle files, the
BOM, and progress as I work on cal/test fixtures, if anyone wants to follow
along. Look for an update when I get organized enough to do that.

What's the height or rather width you used for your finger connector?
I had a similar project for debugging purpose ().
However, I didn't add "margin" on top and bottom, so I have to manually align the extender when inserting.
And so far, I was not able to find mechanical data from Tektronix documentation

My current prototype does this with 4 NPN transistors sourcing 8-4-2-1
weighted currents into a wilson current mirror, nothing harder to source
than 2N3904, 2N3906 and some E96 resistors. Time will tell whether this is
fit for purpose, as always there are plenty of ways to address this issue.

I'll crank up a proper schematic and post here.

I'm currently de-mystifying the timing of the TS<n> signals. The pulses
seem to be approx 130uS wide, negative going 0 - -15V, but the slew rate of
approx 3us/Volt, so the pulse only sits at -15V for approx 20us.
See the yellow trace on this plot:
,
so it looks like I have around 30-40us to set up the 4 currents.
The blue trace on that plot is the derived TTL signal, mimicking the TS
interface circuit used in the 7M13. I am actively looking to change the
circuit to: a) not sit at 1.6V when "low", and switch on harder, and b)
transition faster to maximise the amount of time I have to set up the
current sinks.

On Tue, Jul 27, 2021 at 2:04 PM Ed Breya via groups.io <edbreya=
[email protected]> wrote:

Andy wrote: "For instance, my plan for the readout interface is to create
an SPI-based
sub-system that deals with all the current source and voltage adaptation,
so that it could be easily bolted onto any micro that can field an
interrupt and talk SPI at a reasonable rate."

7K readout interfacing is quite easy, once you're familiar with the
details. I'd recommend using DAC-08 or DAC-10 or equivalent to drive the
currents - these are an ideal match for the circuit conditions. You can
also use CMOS or JFET analog switches with weighting resistors, but the
DACs are more compact, and simpler to set up. You will also need to
synchronize the external control stuff to the internal readout timing to
know when to present the appropriate currents.

In my 7K test plug-in I started years ago, I used four (one for row, and
one for column current, for each channel) DAC-08s, three CMOS logic parts,
and a little diode logic, to make the readout exerciser. It presents all
fifty characters on both channels, ten at a time, in a five step sequence
at about one second per step. This was a simple implementation, due to
using plenty of DACs, which I had in stock. Other schemes could be done,
even with a single DAC and enough multiplexing/sampling/holding and such,
but the beauty of these DACs is that they take care of the level shifting
and current sourcing - no matter how you code and make the current signals,
the actual currents need to flow from the row and column inputs into minus
15 V (or at least some negative supply).

I have a bunch of DAC-08s and -10s set aside just for readouts in custom
plug-in projects. I think the MC1408 can work too. These are all oldies.
There should be newer and better equivalents available. The main thing is
to have 8 bits or more, current sinking output in the 1 mA FS range, and
running from -15 Vee, for simplest interface.

Ed

--
Andy