Date   

Re: More Complete List of Concept Series and Measurements Concepts Books

Chuck Lippmeier
 

After my last posting I googled around and found this link to an index of
downloadable .pdfs of the largest collection of Tek books I've ever seen. It
even has the "Semiconductor Diodes and Transistors" series I mentioned, I
wanted (7 Volumes not just the 2 I knew about). The Concepts books are
listed too.

http://bee.mif.pg.gda.pl/ciasteczkowypotwor/Tek/publikacje/

Chuck Lippmeier


New file uploaded to TekScopes@groups.io

TekScopes@groups.io Notification <TekScopes+notification@...>
 

Hello,

This email message is a notification to let you know that a file has been uploaded to the Files area of the TekScopes@groups.io group.

File: 42W-5850 Preventing Sampling Head Overdrive and Static Damage.pdf

Uploaded By: Egge Siert

Description:
Application Note

You can access this file at the URL:
https://groups.io/g/TekScopes/files/42W-5850%20Preventing%20Sampling%20Head%20Overdrive%20and%20Static%20Damage.pdf

Cheers,
The Groups.io Team


Re: More Complete List of Concept Series and Measurements Concepts Books

 

On 13 Apr 2019, at 14.58, Chuck Lippmeier <chuck@lippmeier.com> wrote:
I also have a Tek book named, "Semiconductor Diodes and Transistors
Programmed Instruction Volume I Basics", Tek Pub 062-0053-00. Printings in
1963, 66, 67 & 68. Inside it mentions that there is also a Volume II "Diode
Devices". Volume I is the most in depth study of semiconductor physics I've
ever seen. That's saying something since I have a BS in electronics. I'd
very much like to own/read other "Programmed Instruction" Tek books
(especially Vol 2 and any volumes in this series) but this is the only one
I've ever seen.
http://w140.com/tekwiki/wiki/File:062-053.pdf

Also, http://w140.com/tekwiki/wiki/Concepts_Series


--
Soren


Re: some way to get alternating display of two different sweep rates on a 7904A?

cmjones01
 

On Sat, 13 Apr 2019, 03:19 John Griessen, <john@ecosensory.com> wrote:

Is some way to get alternating display of two different sweep rates on a
7904A?

I fiddled with a 7904A and 7A19 7A26 7B71 7B92A and seemed to get crossed
controls -- left vert with b horiz
and R vert with A horiz. Then found mention of "independent pairs
operation". I'm going to be digging for that in the manual.
Meanwhile does anyone have some hints for getting one sweep at 200 us/div
and one at 200 ns/div?
Yes, this is certainly possible on the 4-slot scopes. I do it on my 7904A.
Two timebases in the vertical slots. Horizontal mode set to ALT, vertical
to CHOP I think (though it could be the other way round). If one of the
time bases is a dual one like the 7B92A you can even make that trace
intensified or delayed.

I demonstrate it on a 7704A here:
https://youtu.be/Hz-gF_XSj9w

The settings are the same on a 7904A, though I find the 7904A's intensity
controls easier to manage to get a clear display.

Chris


Re: More Complete List of Concept Series and Measurements Concepts Books

Chuck Lippmeier
 

I also have a Tek book named, "Semiconductor Diodes and Transistors
Programmed Instruction Volume I Basics", Tek Pub 062-0053-00. Printings in
1963, 66, 67 & 68. Inside it mentions that there is also a Volume II "Diode
Devices". Volume I is the most in depth study of semiconductor physics I've
ever seen. That's saying something since I have a BS in electronics. I'd
very much like to own/read other "Programmed Instruction" Tek books
(especially Vol 2 and any volumes in this series) but this is the only one
I've ever seen.

Chuck Lippmeier


Re: 577 Curve tracer ringing CRT and noisy step generator

Dave Voorhis
 

On 13 Apr 2019, at 03:44, wilson2115@outlook.com wrote:

I find it interesting at 0 collector voltage the CRT makes a noticeable metal like whine as if some internal metal plates are actually resonating
I picked up a 577 D1 last weekend, and have replaced the CRT — it came with a replacement, due to the original being dim — and a pair of transistors in the Z-axis circuit that died after about twenty minutes of use. I’ll have to recalibrate it due to the CRT change, and storage doesn’t work with the new CRT (but mostly worked on the old one — though the Brightness control had no effect) which I’m hoping is just a calibration problem. Everything else works, though I’m not sure the Display Filter works correctly — that may be the subject of another post.

The only noise I’ve noticed is a faint line-frequency humming from the collector sweep transformer.

However, a metallic whine from (near?) the CRT is something I’ve heard from my 7623 scope in some storage modes, when adjusting the stored display brightness. Given the D1 version of the 577 uses an analog storage CRT similar to that in the 7623, do you (a) have the D1 variant of the 577 and (b) did you have storage turned on?


Re: 7S12 with S-4 and S-53 troubleshooting

Albert Otten
 

Hi Nenad,

DC offset also works, and
Volt/div setting increases noise on the trace with higher sensitivity, so I
figure the vertical block of the 7S12 is OK.

So the main suspect is the S-4, but I have no idea how to troubleshoot it.
I can see the tiny sampling pulses being fed to it by 7S12, but nothing
"notable" on the preamp output on pin 4.
...
How to test the snap-diode?
In my opinion everything from 7S12 up to and including the snap-off pulse to the gate bridge is working. The Offset can only work when the peamplifier generates correction pulses and in turn that can only happen when the snap-off pulses are present.
You won't see a signal from the preamplifier when there are no input changes between sample moments. Correction pulses are only needed then to correct drift in the 7S12 memory circuit and each pulse will be very small.
So somehow the sampling bridge does not pass your 10 MHz input signal. There still might be a response however to the input DC level.
Anyway, I'm afraid fault finding and repair will not be easy. I repaired an S-6 by replacing the whole input block with a new unit (which was much cheaper than buying another S-6) but I have no experience with S-4 repair.

Albert


Re: 7S12 with S-4 and S-53 troubleshooting

Egge Siert
 

Hi Nenad,

I have a pdf of the Application Note which Craig refers to. Contact me off list. Otherwise I shall upload it on TekScopes a.s.a.p. On this moment it is sitting on the Desktop which is now in use as X-Terminal. Reseating IC's in their "famous" TI DIL-Sockets (when you have a pre-1982 build one) will help sometimes.

Greetings,

Egge Siert


Re: Output buffer for 7000 series scopes.

magnustoelle
 

Good Day Gudjon,
that sounds great, and yes, all 7000 series plug-ins I know have the same 50mV/DIV output swing. I have used the mentioned AD807x buffers may moons ago, but the TI/BB buffers are new to me, so thank you for the hint.
Please let us know how your project moves ahead. I just get very excited whenever I see a custom plug-in for Tektronix instruments. Photos would be superb.I have recently finished a simple current sink for the TM500 system and while this is nothing new or advanced, I  have enjoyed building this simple unit a lot. And the design and making connects you with technology; this is your own sweet thing! 
Enjoy designing & building,
Magnus

Hi Dennis and Magnus

Thanks for the ideas.
I would prefer to put the buffer amplifier at the vertical interface
with very short leads. In that way I will
get two channel output from the 7603. There is +-15V on the vertical
interface board which is more than enough.

I made a test feeding the signal output from the left plug-in into a
7A13 in the right compartment.
It works nicely and the differential signal output at this point is 50mV/div.

AD8079 and OPA633 are the buffers that might work. I will do some
simulations and try to build
a circuit and then post info to the list.

Regards
Gudjon


Re: Output buffer for 7000 series scopes.

Gudjon Gudjonsson
 

Hi Dennis and Magnus

Thanks for the ideas.
I would prefer to put the buffer amplifier at the vertical interface
with very short leads. In that way I will
get two channel output from the 7603. There is +-15V on the vertical
interface board which is more than enough.

I made a test feeding the signal output from the left plug-in into a
7A13 in the right compartment.
It works nicely and the differential signal output at this point is 50mV/div.

AD8079 and OPA633 are the buffers that might work. I will do some
simulations and try to build
a circuit and then post info to the list.

Regards
Gudjon


Re: 7A19 has zero output on some steps

Craig Sawyers <c.sawyers@...>
 

After these needing a treatment with bond paper to polish gold contacts, remove dust?
Any other hints about this plugin?
Zero output on some steps could be either the cam switch contacts (like you say. I had to clean both
of mine as a result of exactly the same symptoms) or one of the funky custom ceramic plate attenuator
resistors. You can unclip those and carefully measure with an ohmmeter. One at a time of course so
they don't get mixed up ;-). But they should be OK. If the input was crazily overloaded the equally
funky and unobtainium fuse would blow and there would be zero output on any range.

Craig


Re: 7S12 with S-4 and S-53 troubleshooting

Craig Sawyers <c.sawyers@...>
 

So the main suspect is the S-4, but I have no idea how to troubleshoot it.
I can see the tiny sampling pulses being fed to it by 7S12, but nothing "notable" on the preamp
output
on pin 4. The manual says not to test the sampling bridge diodes using an ohmmeter, but a curve
tracer. How could an ohmmeter (actually DMM, <1mA test current) be more destructive to these
diodes than a curve tracer? (provided that the test is carried out using forward bias only). How to
test
the snap-diode? Is there any other extra-sensitive component I should be aware of?
The reason to use a curve tracer is that it is controlled. You operate it very carefully within the
safe operating area of the tiny diodes and check correct operation both in positive and reverse bias.
I would not even think about deviating from Tek's measurement procedure.

Now sure, the S4 was introduced in the 1960's (and what a design tour de force it was!) when modern
DVM's weren't even a twinkle in the measurement eye. So a meter was something with a 15V battery and a
needle - and 15V in reverse bias would certainly kill a travelling wave sampling diode. But even now
you need to check what the open circuit voltage of your meter is when checking resistance. It needs to
be an absolute maximum of 5V to prevent damage in reverse bias. And it is reverse bias you need to
check - it is that that will particularly reveal whether you have a fried diode. You need to do all
this very, very carefully.

You do know that the input to the S4 (and S6) is exceptionally prone to static damage? Even the static
charge built up on a length of coax can kill an S4. Tek even recommended handling the S4 and S6 on a
static mat with wrist strap.

Mine live with an SMA grounding cap on the inputs until I use them, and then I short circuit every bit
of coax I use when making a connection.

Try and find a copy of the Tek Applications Note 42W-5850 "Preventing Sampling Head Overdrive and
Static Damage".

Craig


Re: some way to get alternating display of two different sweep rates on a 7904A?

John Kolb
 

Independent sweep speeds easy with the 7844 dual beam scope :)
John

On 4/12/2019 7:37 PM, John Williams wrote:
This is exactly what the 547 does. It has a well-engineered diode switch that transfers from one sweep to the alternate one. I have tried to duplicate this for a dual sweep scope like the 535/545 series but have been unsuccessful. I don’t know of any setting or easy way to accomplish this but one of the 7000 series experts may. I would like to know too.


Re: CORRECTED Complete List of Concept Series and Measurement Concepts Books

 

It is a subsection. It seems like they were trying to make an application
note out of that part of the main book.

I included it for completeness.

By the way I don't have the Strain Gauge book either. I have seen the Strain
Gauge Transducer plugin for the 500 series scopes back in the 1960s in the
lab I worked in at the time. Since Tek never did a 7000 version I assume the
strain gauge plugin didn't sell well.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
Craig Sawyers
Sent: Friday, April 12, 2019 10:56 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] CORRECTED Complete List of Concept Series and
Measurement Concepts Books

I incorporated the additional books I missed I included ALL of the
authors.
This is the CORRECTED complete list.
Dennis Tillman W7PF
Dang. I thought I had the lot - and now I realise I'm two short!

062-0710-00 Measurements Concepts Strain Gauge Measurements Concepts
(Les
Hurlock)

062-1246-02 Measurement Concepts Transducer Applications Handbook
(Reprint
of Ch. 5, Ch. 6, Glossary, and Appendices of "Transducer Measurements")

Although from what you say this looks like it is a subsection of
Transducer Measurements, which I have.

Craig





--
Dennis Tillman W7PF
TekScopes Moderator


Re: 577 Curve tracer ringing CRT and noisy step generator

 

Hi Wilson,

First, It looks like you are AC Coupled. Switch to DC so the waveform will be clearer.
It appears the spikes are occurring at random places in the steps. Since the collector voltage is just rectified AC from the power line, the base steps have to be synchronized to the 60Hz as well. If the spikes are being caused by anything at all in the power supply the spikes would occur at the same point in each of the steps. But these spikes occur at different places in the steps so the cause is not in the power supply.

I suggest you do two things:
1) Work backwards in the base step generator circuit until you find the point where the spikes on the steps first show up. The cause will be at that point in the schematic.

2) try varying the front panel controls that might cause the spikes to change in some way. Hopefully if you can get that to happen it will give you a clue where to look in the schematic. Some suggestions for what to change and report the results you observe when you do:
* Do the steps move around each time your scope sweep triggers again? or do they repeat exactly like this every time?
* What happens if you reduce the number of steps by 1 each time. Do the spikes change or move somewhere else?
* What happens if you increase or decrease the STEP AMPLITUDE.
* What happens if you turn the STEP AMPLITUDE knob to the Voltage steps
* What happens when you switch the step rate to all three settings: SLOW, NORM, and FAST?
* What happens when you change the STEP/OFFSET POLARITY from NORMAL to INVERT.
* What happens when you add or subtract offset to the steps.

All of these things may give us the clue we need to finally figure out what is causing this.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
wilson2115@outlook.com
Sent: Friday, April 12, 2019 8:36 PM
Subject: Re: [TekScopes] 577 Curve tracer ringing CRT and noisy step
generator

https://groups.io/g/TekScopes/photo/86536/0?p=Created,,,20,2,0,0

Probing the base to emitter on the test fixture, notice the spikes



--
Dennis Tillman W7PF
TekScopes Moderator


Re: CORRECTED Complete List of Concept Series and Measurement Concepts Books

Craig Sawyers <c.sawyers@...>
 

I incorporated the additional books I missed
I included ALL of the authors.
This is the CORRECTED complete list.
Dennis Tillman W7PF
Dang. I thought I had the lot - and now I realise I'm two short!

062-0710-00 Measurements Concepts Strain Gauge Measurements Concepts (Les
Hurlock)

062-1246-02 Measurement Concepts Transducer Applications Handbook (Reprint
of Ch. 5, Ch. 6, Glossary, and Appendices of "Transducer Measurements")

Although from what you say this looks like it is a subsection of Transducer Measurements, which I
have.

Craig


Re: 577 Curve tracer ringing CRT and noisy step generator

 

Hi Wilson,
That shouldn't be! I have had at least 5 or 6 577s and none of them made any noise at all under any circumstances.
Dennis Tillman W7PF

-----Original Message-----
From: wilson2115@outlook.com
Sent: Friday, April 12, 2019 7:45 PM
Subject: 577 Curve tracer ringing CRT and noisy step
generator
<snip>
I find it interesting at 0 collector voltage the CRT makes a noticeable
metal like whine as if some internal metal plates are actually
resonating



--
Dennis Tillman W7PF
TekScopes Moderator


Re: Complete List of Concept Series and Measurements Concepts Books

Craig Sawyers <c.sawyers@...>
 

http://w140.com/tek_strain_gage_measurement_concepts_ocr.pdf

062-0710-00

-Bob
Good heavens - I haven't seen that in any of the Concepts series lists. Now I'm paranoid - I haven't
got it!

Craig


Re: some way to get alternating display of two different sweep rates on a 7904A?

 

Hi John,

This seems like a simple thing to do and since I know how much you know
about Tek scopes I must be missing something. Can you be much more specific
about what you want:
* In your ideal configuration what plugins would you be using and what slots
would they be in?
* What signal in the A vert do you want to go to what timebase in what
horizontal slot?
* What signal in the B Vert do you want to go to what timebase in the other
horiz slot?
* What signal do you want to trigger each timebase off of?

In the setup section of the 7904A manual they explain the 20 possible
vertical and horizontal mode combinations. It starts on pg 2-11 of the 7904A
manual.

Dennis Tillman W7PF

-----Original Message-----
From: John Griessen
Sent: Friday, April 12, 2019 6:19 PM
Subject: [TekScopes] some way to get alternating display of two
different sweep rates on a 7904A?

Is some way to get alternating display of two different sweep rates on
a 7904A?

I fiddled with a 7904A and 7A19 7A26 7B71 7B92A and seemed to get
crossed controls -- left vert with b horiz and R vert with A horiz.
Then found mention of "independent pairs operation". I'm going to be
digging for that in the manual.
Meanwhile does anyone have some hints for getting one sweep at 200
us/div and one at 200 ns/div?



--
Dennis Tillman W7PF
TekScopes Moderator


Re: 577 Curve tracer ringing CRT and noisy step generator

DW
 

https://groups.io/g/TekScopes/photo/86536/0?p=Created,,,20,2,0,0

Probing the base to emitter on the test fixture, notice the spikes

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