Retirement works like that IN THEORY. IN PRACTICE it is somewhat different. I have been retired 9 years, 4 surgeries on my hands, 2 hernia repairs and 2 cancers, Kidney removal and partial lung removal, no I never smoked. The good part of the cancers was each was a separate cancer.I have not had to have Chemo or Radiation, 4 years and counting on the lung and 6 years on the Kidney.?Leon Robinson ?? K5JLR Political Correctness is a Political Disease. From: Adrian <Adrian@...> To: [email protected] Sent: Monday, March 19, 2018 3:08 AM Subject: Re: [TekScopes] PG506 Relays Not sure it would simpler or cheaper to be honest - given the whole board is not much larger than the two relays anyway and, in mine at least, has only a couple of diodes and some .1" headers in addition to the relays. You would also need to get the existing relays out without wrecking the board. I thought I had a relay issue a while back but at the moment it's working again so I moved the PCB creation to the rainy-day list. I'm probably going to regret that at some point, although if I stick to plan and finally retire before I hit 70 that means I can declare every day an official 'Rainy-Day' very soon and spend my time doing whatever I like doesn't it? Or does retirement not work like that? Adrian On 3/19/2018 6:35 AM, Michael A. Terrell wrote: Is there room for a small daughterboard? That would be simpler than a whole new PCB.
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Re: What calibration items to buy.
From what I've read, unsaturated cells have a short life, about 10 years, whereas saturated cells are almost immortal. (Voltage falls, and TC and hysteresis rise.) An old unsaturated cell meeting spec today would be some kind of miracle. They were popular nevertheless, because they had low TC and could stand jostling. Dave Wise ________________________________________ From: [email protected] < [email protected]> on behalf of Robin Birch <robinb@...> Sent: Saturday, March 17, 2018 3:43 PM To: [email protected]Subject: Re: [TekScopes] What calibration items to buy. Tom, Think mine¡¯s an unsaturated one - if I drop it down can you measure it ? Robin On 17 Mar 2018, at 22:40, Chuck Harris <cfharris@...> wrote:
Hi Tom,
Those look right to me for saturated standard cells.
Find a nice cozy place for them to live, and leave them
alone, and they should last and last.
-Chuck Harris
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Re: Protecting button labels
Yes, I can remember doing that :-)
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Adrian Sent: 19 March 2018 11:44 To: [email protected]Subject: Re: [TekScopes] Protecting button labels Technically we may be talking about the typeface, I think the font is the collection of all the elements that make up a given typeface (weight, style, width etc)? Other GOM* points: There have been typefaces/fonts pretty much since Gutenberg's time (1440s?) Panels for electronic equipment with legends existed well before Letraset came along! When I started, our fonts were in boxes of engraved brass letters and we had a pantograph engraver to get the scaling right on the panel - and woe betide you when you made a 'typo'! *=Grumpy Old Man Adrian On 3/19/2018 10:08 AM, Robin Birch wrote: Not sure that this is actually a ¡°font¡± it looks like one of the
drawing office stencil or letraset ones used for this sort of thing
back to the dawn of electronics
Robin
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Re: Protecting button labels
The way that these were made was that the drawing office would draw the lettering and markings for each colour. If all the same colour then one drawing. They may have been drawn larger than full size and then reduced photographically. It is possible that a copper plate set of lettraset transfers was available or a stencil but they were drawn and then put photographically onto a clear film that was the correct size. This was then used to make a silk screen through which the front panels were printed before assembly.
Copper plate was around then (Created 1901 - full name Copperplate Graphic which means Sans Serif) but there were several drawing office fonts that didn't actually have a name and were just used for lettering. Some of the ones that were used to make originals 4 or 5 or 10 times bigger than the final product were actually hand drawn as this gave a higher quality shape once photo reduced. Even if they used copperplate stencils or lettraset they still effectively hand drew it all.
If multiple colours then drawn in black for each colour and then printed separately, one screen for each colour.
Remember, no desk top printing, just pen and ink.
Robin
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of toby@... Sent: 19 March 2018 14:42 To: [email protected]Subject: Re: [TekScopes] Protecting button labels On 2018-03-19 6:08 AM, Robin Birch wrote:
* Some of the older scopes used Copperplate. e.g.
/g/TekScopes/photo/12929/2?p=Name,,,20,1,0,0
Not sure that this is actually a ¡°font¡± it looks like one of the
drawing office stencil or letraset ones used for this sort of thing
back to the dawn of electronics
It's the Copperplate typeface. Definitely not a stencil. The family has several members. --Toby Robin
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Re: Tek 317 odd trace behavior after warm-up
OK great, a dead cap, hopefully that will fix it.
As soon as it's replaced, measure the output of the voltage regulator tube, it's the most important thing, this thing is the reference ;-)
Vince
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Re: Protecting button labels
On 2018-03-19 6:08 AM, Robin Birch wrote:
* Some of the older scopes used Copperplate. e.g.
/g/TekScopes/photo/12929/2?p=Name,,,20,1,0,0
Not sure that this is actually a ¡°font¡± it looks like one of the drawing office stencil or letraset ones used for this sort of thing back to the dawn of electronics
It's the Copperplate typeface. Definitely not a stencil. The family has several members. --Toby Robin
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Re: Tek 7623A (or 7000 series in general) - Poor man's choice to Signal Standardizer
Thanks Spin,
It was crossing my mind to do something like that, but then, If I
eventually make a board, I will build it the single-ended to balanced
output converter directly onto it, connected as short as possible to the
mainframe's input pins, to avoid as much as possible any artifacts being
introduced by the coaxial cables, which I want to avoid, exactly to not
fall in the loophole of needing another calibrated instrument to calibrate
the instrument.
My rational goes in line with the Leo Bodnar's pulser, which is nothing
more than the very fast line driver that's known to produce a clean pulse
right-out-of-the-box, but doesn't need to be anything as fast as Leo's
pulser, because that one is good for, say, 1GHz, while I`m only trying to
do something good enough for 100MHz.
What circuit / IC did you use for your single-ended to balanced output?
Rgrds,
FT
2018-03-18 14:57 GMT-03:00 <thespin@...>:
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Here's how I did it. I made a board that plugged into the back of the unit
(if people are interested, I'm more than happy to post the kicad files)
with a pair of BNC connectors. I then made an additional board that did the
requisite common mode to differential conversion. I drove this board with a
calibrated function generator, verifying the voltages going to the
mainframe with a DMM.
I was thinking of making a pair of calibrator boards using more modern
parts... one for step response cal using a high speed comparator, and one
for voltage calibration using a dac and microcontroller to get the
calibration waveform. Wouldn't snap in like an official module, but would
plug into the back of the unit, being held in by the friction of the
fingers of the card edge connector. Would people be interested in this?
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
Also back in the 80's I was developing pulsed solid state lasers at Southampton University in the UK,
and the Q-switch (an electro-optic polarisation rotator) was fired using a krytron. The main
application of these was as a nuclear weapon trigger, so they were difficult to get, involved massive
paperwork, and it was only possible to purchase a new one if you returned the dead one first. Made by
EG&G. Nowadays it would be a formal ITAR process.
These tiny triggered valves (about the size of the end of your thumb) could hold off 5kV, and
discharge the Q-switch (which was essentially capacitive) in <1ns with kA circulating currents. At
100Hz day after day for about 6 months then sayonara Krytron. Then a pain in the ass to get a
replacement.
Craig
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-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Roger Evans via Groups.Io
Sent: 19 March 2018 11:12
To: [email protected]
Subject: Re: [TekScopes] 550V 3.2nSec Pulse Generator Metrotek MP 203
Back in the mid-80s I had some friends at Imperial College in the UK who started a company called
Kentech. Their speciality was fast pulse generators that could switch around 2kV with a pulse
duration
of about 5nsec or less, they sold mainly into the weapons labs in the US and UK for gating X-ray
image
intensifiers. After a few years they were willing to say something about the technology and
admiited
it was a stack of avalanche transistors and the secret was the device selection and the propagation
of
the trigger pulse. This looks very similar with the companies intellectual property protected by
the
potting.
Nice find Dennis,
Regards,
Roger
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Re: Protecting button labels
Technically we may be talking about the typeface, I think the font is the collection of all the elements that make up a given typeface (weight, style, width etc)?
Other GOM* points:
There have been typefaces/fonts pretty much since Gutenberg's time (1440s?)
Panels for electronic equipment with legends existed well before Letraset came along!
When I started, our fonts were in boxes of engraved brass letters and we had a pantograph engraver to get the scaling right on the panel - and woe betide you when you made a 'typo'!
*=Grumpy Old Man
Adrian
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On 3/19/2018 10:08 AM, Robin Birch wrote: Not sure that this is actually a ¡°font¡± it looks like one of the drawing office stencil or letraset ones used for this sort of thing back to the dawn of electronics
Robin
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
Back in the mid-80s I had some friends at Imperial College in the UK who started a company called Kentech. Their speciality was fast pulse generators that could switch around 2kV with a pulse duration of about 5nsec or less, they sold mainly into the weapons labs in the US and UK for gating X-ray image intensifiers. After a few years they were willing to say something about the technology and admiited it was a stack of avalanche transistors and the secret was the device selection and the propagation of the trigger pulse. This looks very similar with the companies intellectual property protected by the potting.
Nice find Dennis,
Regards,
Roger
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Re: Protecting button labels
* Some of the older scopes used Copperplate. e.g.
/g/TekScopes/photo/12929/2?p=Name,,,20,1,0,0
Not sure that this is actually a ¡°font¡± it looks like one of the drawing office stencil or letraset ones used for this sort of thing back to the dawn of electronics Robin
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Re: Protecting button labels
I'm pretty sure it's Futura up to the late 1960s, then Univers after that. Chris On Sun, Mar 18, 2018 at 10:55 PM, Dennis Tillman W7PF <dennis@...> wrote: Does anyone know what font they used in the manuals? I always thought it would be nice to make the manuals in the same font Tek used when my project is something that other Tek users can use on their equipment.
Dennis Tillman W7PF
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of toby@...
Sent: Thursday, March 15, 2018 8:10 AM
To: [email protected]
Subject: Re: [TekScopes] Protecting button labels
<snip>
They used Univers and Univers Condensed, in various weights, on just about all modern models (from late 1960s up to quite recently, e.g. my
TDS460A) - examples:
- Univers: /g/TekScopes/photo/12929/3?p=Name,,,20,1,0,0
- Univers and Univers Condensed:
/g/TekScopes/album?id=14929 (this is my scope)
--Toby
* Some of the older scopes used Copperplate. e.g.
/g/TekScopes/photo/12929/2?p=Name,,,20,1,0,0
Craig
--
Dennis Tillman W7PF
TekScopes Moderator
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Not sure it would simpler or cheaper to be honest - given the whole board is not much larger than the two relays anyway and, in mine at least, has only a couple of diodes and some .1" headers in addition to the relays. You would also need to get the existing relays out without wrecking the board.
I thought I had a relay issue a while back but at the moment it's working again so I moved the PCB creation to the rainy-day list. I'm probably going to regret that at some point, although if I stick to plan and finally retire before I hit 70 that means I can declare every day an official 'Rainy-Day' very soon and spend my time doing whatever I like doesn't it?
Or does retirement not work like that?
Adrian
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On 3/19/2018 6:35 AM, Michael A. Terrell wrote: Is there room for a small daughterboard? That would be simpler than a whole new PCB.
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Is there room for a small daughterboard? That would be simpler than a whole new PCB.
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-----Original Message----- From: Chris Don <chd3@...>
Sent: Mar 17, 2018 10:31 AM
To: [email protected]
Subject: [TekScopes] PG506 Relays
Hi all,
As many before me, I need to replace the relays on a PG506.
The original Potter & Brumfield T10-0010-2 are of course no longer available.
Has anyone ever found a workaround, to replace those relays with models currently available on the market (e.g. Panasonic SF4D)?
Electrically speaking it is a piece of cake; the issue lies with terminal layout.
The relay PCB is pretty straightforward, shouldn't be too difficult to design a new one...
Any experience with this?
Thank you,
Chris
Michael A. Terrell
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
Hi Brasscat,
Yes but the duty cycle is infinitesimal. The pulse lasts less than 100nSec and it repeats every ~100uSec. So the ratio is at least 1:1000. That would make 5KW act more like 5W. But I didn't detect any heating of the 50 ohm termination I used at all. It was a standard Tek 2W terminator/feedthru.
Dennis Tillman W7PF
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of brasscat Sent: Sunday, March 18, 2018 7:20 PM To: [email protected]Subject: Re: [TekScopes] 550V 3.2nSec Pulse Generator Metrotek MP 203 My goof! That's 5.5KW. -- Dennis Tillman W7PF TekScopes Moderator
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
Guess I am real tired, how about 6.05KW
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
I guess the pulse is so short that you can get away with that, but during
the pulse it's 550 watts. I was thinking a transmitter dummy load / attenuator
to start with.
Stan KO6YB
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Re: Typefaces in Tektronix manuals, was Re: [TekScopes] Protecting button labels
Hi Toby,
Thank you, That is a very detailed list.
Dennis Tillman W7PF
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of toby@... Sent: Sunday, March 18, 2018 5:33 PM To: [email protected]Subject: Typefaces in Tektronix manuals, was Re: [TekScopes] Protecting button labels On 2018-03-18 5:55 PM, Dennis Tillman W7PF wrote: Does anyone know what font they used in the manuals? I always thought it would be nice to make the manuals in the same font Tek used when my project is something that other Tek users can use on their equipment.
I can't speak for all manuals, but of ones that I have, this is typical: e.g. 465 Service Manual * Front cover: Eurostile extended (bold and light) - TEKTRONIX and "INSTRUCTION MANUAL" * Title page: Univers Condensed Bold ("465 OSCILLOSCOPE") and Univers Roman ("SERVICE"); Univers Roman weight for small body text * TOC and internal pages, All Univers, apparently bold except chapter headings which are Roman weight * Subheadings, image captions, folios, headers and footers are Univers Bold FWIW, the body text of the manual appears to be set on an IBM Selectric, so this is Selectric Univers. Headings are probably photoset separately (like the instrument front panel art). Some especially bold headings (e.g. "ELECTRICAL PARTS LIST" and the "CAUTION", "WARNING" headings) appear to be Franklin Gothic Heavy Oblique, or a very similar gothic. The text on the parts list cover pages (apart from the typewritten text in Courier), including the table headings, is in Futura. Foldouts are all in Univers and Univers Bold, like the rest of the manual. If somebody has a manual from a different period or style they'd like me to look at, please post page images in the gallery section and reply. --Toby Dennis Tillman W7PF
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
toby@...
Sent: Thursday, March 15, 2018 8:10 AM
To: [email protected]
Subject: Re: [TekScopes] Protecting button labels
<snip>
They used Univers and Univers Condensed, in various weights, on just
about all modern models (from late 1960s up to quite recently, e.g. my
TDS460A) - examples:
- Univers:
/g/TekScopes/photo/12929/3?p=Name,,,20,1,0,0
- Univers and Univers Condensed:
/g/TekScopes/album?id=14929 (this is my scope)
--Toby
* Some of the older scopes used Copperplate. e.g.
/g/TekScopes/photo/12929/2?p=Name,,,20,1,0,0
Craig
-- Dennis Tillman W7PF TekScopes Moderator
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Re: 550V 3.2nSec Pulse Generator Metrotek MP 203
Hi Brasscat,
Good point. I was so busy figuring out how I was going to measure the voltage that I forgot about the current going into the 50 ohm resistor. I was really amazed at the amplitude. I first tried it on a 7A24 and I had to keep adding attenuators to get it on screen. Eventually I had a stack of about 6 attenuators in a row before I finally reduced the amplitude to a few volts. It is a good thing I always test signals on a 7A24 first before I connect them to a sampling head.
Dennis Tillman W7PF
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of brasscat Sent: Sunday, March 18, 2018 6:37 PM To: [email protected]Subject: Re: [TekScopes] 550V 3.2nSec Pulse Generator Metrotek MP 203 Hey Dennis, that's one heck of a pulse! 11A 550V! -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Dennis Tillman W7PF Sent: Sunday, March 18, 2018 4:49 PM To: [email protected]Subject: [TekScopes] 550V 3.2nSec Pulse Generator Metrotek MP 203 For more years than I can remember I have been collecting, or at least documenting, the odd-ball TM500 / TM5000 plugins I come across. But I don't always try them when I get them to see what they do. Kurt Rosenfeld (TekWiki) asked me to bring a bunch of my unusual plugins to the VintageTEK Museum to photograph a few weeks ago. That got me curious about several of them. Out of curiosity I decided to try a few of them to see what they do. A couple of the plugins contained some real surprises. The Metrotek MP 203 Pulser is definitely one of them. You can see a picture of what this looks like on TekWiki at It is obviously a pulse generator, but I had no idea how unusual it was until now. It puts out 10V negative going pulses at first glance but that is not how it is supposed to be terminated as I discovered. When you connect a 50 ohm termination to the output the pulse suddenly becomes a negative going 550V monster. The fall time of this huge pulse is 3.2nSec. The repetition rate can be varied up to about 11.7KHz. The only I could figure out how to measure the actual amplitude of a pulse this large and still indicate the edge speed was with a P6009 100X 100MHz probe. I measured the actual fall time of the pulse with a 7S11 / 7T11 / S4. To do this safely I had to attach 45dB of attenuators between the generator and the sampling head to reduce the amplitude of the pulse to 700mV to protect the S4 sampling head from being blown out. The insides are VERY unusual. I certainly have no idea what the design is based on other than there must be a very high voltage avalanche transistor in the heart of this plugin. If it is an avalanche transistor then it must be contained in the small 2" x 2" blue square marked Pulse Generator. I sent Kurt pictures of the pulse it generates and of the insides of this very unusual plugin. He has added them to the web page he has for it. Dennis Tillman W7PF -- Dennis Tillman W7PF TekScopes Moderator
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Vince
Fabio Trevisan
Michael A. Terrell