Date   
Re: 11801 NVRAM

Albert Otten
 

Reg,

Fun indeed!!
I tried your setup with less sophisticated signal source:
CSA803, internal triggering, 1 ps/div, 1024 points. FG504 set for triangle waveform approx 100 kHz. FG504 trigger out connected to A input of DC510. CSA Calibrator output connected to input B of DC510. DC510 set for measurement of frequency ratio B/A. Attenuators where appropriate.
With FG504 fine tuning I could obtain a just slowly moving display (somewhat erratic of course, moving backward and forward), good enough to freeze with the Run/Stop button. The frequency ratio was 0.9989-0.9990, or about 1 promille difference. The frozen displays nicely showed one triangle period. Cursor measurements of delta-t between nearly endpoints with equal vertical value scattered around 10 ps in repeated measurements.

Albert

Re: From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Kevin Wood G7BCS
 

Exactly the same story with my 546, but with a different ending. It was donated to the school by the local Marconi factory and sat in the science lab at school gathering dust for several years while we used the basic junk that the school was issued.

Eventually I asked why it was never used. Too many knobs! Nobody could understand it. I made a cheeky offer and it came home in my mother's wheelbarrow!

30+ years later and with the benefit of one of Chuck's transformers it still works very nicely!

Kevin
G7BCS

On 16/09/2019 21:57, Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.
Dave Wise

Re: 3.5mm connector for SD24 sampling head...

Chuck Harris
 

If you have a hankering for SD24 porn, there is a complete
tear down, with high resolution pictures on the tekwiki.

I am familiar with working brass. I suspect that this could
be done, but I have no confidence that the connector will
be accurate afterwards. Annealing brass requires you to
heat it to dull red, and then immerse it in water...sort of
the opposite of what you do with steel. I am sure that the
teflon would be ruined.

The connector doesn't look like a solder type. It appears,
from the pictures, to be screwed into a solid block, and
perhaps makes spring contact with the circuit board.

-Chuck Harris

Reginald Beardsley via Groups.Io wrote:

That's the sort of thing an expander plug can fix. However, I'd expect to spend most of a day on such a project. But that's because I'm a novice machinist. Not too sure that replacing the connector would be any easier though.

BTW brass work hardens very quickly and attempting to anneal the connector in place might not work out well. Though if you were lucky it would just unsolder it. Once it work hardens, further cold working will crack the metal. So I'd approach attempting to repair the connector with the expectation that I might have to replace it. You would only get one try at reforming the metal.

I would like to get a non-working head to take apart and study. I just don't want to spend too much on one. Certainly not the $200+ some people ask on ebay for "parts only" heads.

Reg



Re: From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Chuck Harris
 

:-)

Kevin Wood G7BCS wrote:

Exactly the same story with my 546, but with a different ending. It was donated to
the school by the local Marconi factory and sat in the science lab at school
gathering dust for several years while we used the basic junk that the school was
issued.

Eventually I asked why it was never used. Too many knobs! Nobody could understand it.
I made a cheeky offer and it came home in my mother's wheelbarrow!

30+ years later and with the benefit of one of Chuck's transformers it still works
very nicely!

Kevin
G7BCS

On 16/09/2019 21:57, Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early
70's, where one electronics classroom had a 514D in a back corner. I always felt
sorry for the poor old thing, which was never touched as far as I know. Also
covetous; but the teacher wouldn't give it up. It was the best instrument in the
room, our assigned tools being RCA service-grade boxes.

Dave Wise


Re: OFF TOPIC- Fluke handhelds

Lawrance A. Schneider
 

I have one. A Fluke 97. Like new. Make an offer.

larry

Re: From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Chuck Harris
 

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:

Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise

Re: OFF TOPIC- Fluke handhelds

Richard Solomon
 

Condition ? Accessories ?

73, Dick, W1KSZ

On Mon, Sep 16, 2019, 2:34 PM Lawrance A. Schneider <llaassllaaass@...>
wrote:

I have one. A Fluke 97. Like new. Make an offer.

larry



Re: OFF TOPIC- Fluke handhelds

Lawrance A. Schneider
 

It has all accessories. Also has manual. I’m about to eat - we have guests. I can send pictures if you like.

larry

On Sep 16, 2019, at 5:37 PM, Richard Solomon <dickw1ksz@...> wrote:

Condition ? Accessories ?

73, Dick, W1KSZ

On Mon, Sep 16, 2019, 2:34 PM Lawrance A. Schneider <llaassllaaass@...>
wrote:

I have one. A Fluke 97. Like new. Make an offer.

larry




Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

 

Am I missing something?
Did anyone look in the service manual for the part number and the manufacturer code number?
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of uniacke1 via Groups.Io
Sent: Monday, September 16, 2019 1:32 PM

Any chance it's a 3 pin LEMO variant? Tek used these in other probes as well, e.g. P6407
http://w140.com/tekwiki/wiki/LEMO_S-series_connector
catalog:

http://w140.com/lemo_unipole_multipole.pdf




--
Dennis Tillman W7PF
TekScopes Moderator

Re: From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Dave Wise
 

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 2:38 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise

Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

Dave Daniel
 

Well, the manufacturer and part numbers are on the mating connectors, so one can tell what they are directly. They are both Sealectro (which is what the OP wrote) with different part numbers for each half. I can see the part numbers, but I can't read them. I'll need to find a magnifier. They are not Lemo connectors.

I don't see the usual Tektronix-to-actual manufacturer list in the manual, and the manual is a bit confusing. I have been trying to decipher it. The Sealectro connectors seem to be called out as single-conductor connectors (item ref. no. 37), but that can't be right. It is shown on the schematic (J60) and shown as a three-pin round connector.

I'm confused. I also have one eye temporarily out of commission,so that is not helping matters.

DaveD

On 9/16/2019 5:48 PM, Dennis Tillman W7PF wrote:
Am I missing something?
Did anyone look in the service manual for the part number and the manufacturer code number?
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of uniacke1 via Groups.Io
Sent: Monday, September 16, 2019 1:32 PM

Any chance it's a 3 pin LEMO variant? Tek used these in other probes as well, e.g. P6407
http://w140.com/tekwiki/wiki/LEMO_S-series_connector
catalog:

http://w140.com/lemo_unipole_multipole.pdf



Re: 11801 NVRAM

Reginald Beardsley
 

Albert,

I am reporting what the frequencies of the trigger and ramp generated by the 33622A are and what the time/division of the 11801 is set to. The 33622A frequencies are accurate to more digits than I have shown. ~1.1 ns is the difference in the length of the trigger clock period and the ramp period. The 33622A is *much* more stable than the 11801 clock.

At 512 & 1024 samples the 11801 will allow 1 ps/div. As you increase the number of samples, the minimum time per division increases. The limit is 10 femtoseconds interval between adjacent sample points. So as you increase the number of points in a sweep, the minimum time per division increases.

With a 100 kHz ramp displayed with 1024 points spaced at intervals of 10 fs, the display is only showing 1 out of every million possible samples along the ramp.

With 1024 samples at 10 fs intervals, it makes 4 obvious sweeps with 200 fs jitter between the start of each sweep. It generally shifts slightly every 4 sweeps and 4 sweeps take place faster than I can count. When the OXO heater turns on it moves like mad for about 10-20 seconds before it settles down again. At 5120 samples at 10 fs intervals it makes 2 obvious sweeps. The jitter is tough to estimate at 5 ps/div. but looks to be around 200 fs. There is some indication that there might be 32 sweeps in a set, but I have not been able to find a way to verify that.

Have Fun!
Reg

Tektronix 7854 Digitization Issue

Kyle Rhodes
 

Hi all,

I've got a wonderful 7854 acquired from a fellow list member, but I'm
having an issue with it. The digitization / storage function is not
working properly. Allow me to explain:

It acquires waveforms, but it's as though it's acquiring two different
waves, one at the correct frequency, and one approximately 1/5 the period.
I posted a video to YouTube showing an acquisition, you can clearly see
another superimposed portion of the wave across the entire sweep.

https://www.youtube.com/watch?v=vUq_e4OoAPA

The samples average out a bit if you run 10 or 100 acqs, but obviously it
doesn't result in a nice digitized waveform.

Also, the rendered text gets wonky during an acquisition. I'm not sure if
this is normal, or maybe it's related to the issue?

It's as though the time axis is not correlated properly with the Y axis
sample. Has anyone else encountered such a problem? This is a complex
unit, and before I spent many hours digging through the documentation and
learning how it works, I thought I'd ask for some starting points. Time is
money, and while I love working on this stuff, my day job involves using my
collection of equipment to produce other goods, so the less time spent
troubleshooting, the better. :)


Thanks,
Kyle

Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

 

I have 454 manual document 070-0617-00.

The power sockets are 2 pieces 131-0438-00, shown as part 84 in fig. 1, "Front".
The parts list shows them as "CONNECTOR, 3 contact, female".
In the schematic diagram they can be seen as "U123B" and "J123" in dwg 14
In the mechanical parts list they are shown as "J1238" and "J1239", which makes more sense.

Raymond

Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

Tom Li
 

Thanks for everyone's response.

After some researches in the mailing list archive, currently I highly suspect it's a
LEMO connector, model 303. I've already ordered one EGG.00.303.CLL. I'll update
the thread and report back when my package arrives.

Tom Li.

Re: 561B Recapping

David Holland
 

Yes, but I'd like to have some replacements in mind... They won't
last forever, and I'm eyeing restoring some assorted plugins of
unknown status, and so, I'd like to have the mainframe in a known
healthy state...

I've also a RM567 sitting on the shelf that is in definite unknown
status that may (or not) need similar diagnosis...

There are approximate current limits in the IRB for the 561A (and by
proxy the 561B) I suppose I can putter around in LTSpice, read some
linear PSU design guides, and make some slightly less wild guesses..

On Mon, Sep 16, 2019 at 2:13 PM widgethunter via Groups.Io
<tubesnthings=aol.com@groups.io> wrote:

If it aint broke don't fix it!!!Running several 561As & 565 in original condition with NO issues.That is the norm for 500 series gear.Bernie Schroder



-----Original Message-----
From: Glydeck via Groups.Io <glydeck=aol.com@groups.io>
To: TekScopes <TekScopes@groups.io>
Sent: Sun, Sep 15, 2019 5:15 pm
Subject: Re: [TekScopes] 561B Recapping

I would be interested as well. — George
On Sep 15, 2019, at 1:17 PM, David Holland <david.w.holland@...> wrote:

Anyone recapped a Tektronix 561B, and have some pointers for capacitor
replacement specifications? (ESR/DF & ripple current ratings
particularly)

Looking up the Tektronix part numbers will lead to NSN numbers, which
will give original manufacturers, (Sprague/Mallory), and purported
original part numbers, that I can not find references to.

There's nothing I'm aware of specifically wrong with the scope at the
moment, other than 47 years on those caps - based on the 1972 date
codes, and a serial # in the B19xxx range.

There is also 2 (of 3) tantalum capacitors that don't seem to be
de-rated particularly well (C11 & C31). - (Yes, they look like
tantalum, the NSN's say they are tant., and their tiny physical size
strongly implies it as well.)

I've a DER DE-5000 and a HV supply (Eico 950B) so I could pull them
and measure DF/ESR/leakage/etc to my hearts content, but if I'm going
to remove them, I'd just as soon put new caps back in circuit.

Suggestions? Comments? Cries of Derision?

Thanks,

David






Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

 

TekWiki is unable to confirm it either, it says "The 015-0073-00 (power supply) has
a 3-pin probe power connector (Sealectro 55-850-0018-98?)", note the question mark,
and worse, I was unable to find that Sealectro part.
The rim of the sockets on one of my 454's is marked "Sealectro" and "950-0019-00".

After some researches in the mailing list archive, currently I highly suspect it's a
LEMO connector, model 303. I've already ordered one EGG.00.303.CLL. I'll update
the thread and report back when my package arrives.
I'm pretty sure it is *not* (compatible with) a Lemo connector: The "Sealectro" has an internal "shim" that the Lemo doesn't have, the Lemo has an "outward dent" in the rim which the 454's doesn't have (it has one in the teflon center body) and the bushings form an equilateral triangle in the 454's, whereas the Lemo 303's contacts as per the catalog drawing don't. I haven't checked exact measures and
unfortunately, I cant suggest a number nor supplier for the 454's sockets.

The later 4-pin probe power sockets are Lemo.

Raymond

Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

 

Correction:
The rim of the sockets on one of my 454's is marked "Sealectro" and "950-0019-86", *not* "950-0019-86".

Raymond

Re: Identify the 3-pin Sealectro power Connector from 454 scope for P6045 probe

 

This is getting embarrassing, although it's only 2:00 AM where I live:

Correction of my correction a few moments ago:

It should read

"The rim of the sockets on one of my 454's is marked "Sealectro" and "950-0019-86", *not* "950-0019-00".

Raymond

Re: From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Dave Seiter
 

What kind of oil was used? I ask because one of mine (I think the 511a) seemed like it was filled with wax, or at least what leaked out long ago looks/feels like wax. What was the reason for burying the HV in oil? One of these days I'm going to have to open both of them up because neither works.

On Sep 16, 2019, at 3:13 PM, Dave Wise <david_wise@...> wrote:

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 2:38 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise