Date   

Re: 2465B on a 200C scope cart?

Jean-Paul
 

Hello, good question:

I have several 2465/7/B and carts.

Not a problem to mount the scopes, feet and straps need careful fiddling to position.

I recall t scope rests about 1" forward of the expected position so front cover can fit.

The feet on the scope were not removed.

Finally the straps must be carefully secured or the scope can fall off at high tilt angles.

Bon Chance,


Jon


Re: Getting calibration equipment calibrated

Dave Peterson
 

I might be a bit of an odd bird: I quite enjoy twiddling the variety of pots vs. pure automation. I work in the IC industry, so I get my fill of high level integration, and have spent many hours in the lab with high-end scopes. I could quite easily, and may yet, take in some equipment to check in out at high speed. I'll have to talk to the lab manager. This habby came up after the COVID lock-down. Haven't been in the lab since.

Here's a video of our lab showing our first HBM DDR. I did timing closure on the HBM Phy.

https://www.youtube.com/watch?v=_ug1CLendf8&t=39s


It would be worth seeing, for example, the actual edges coming out of the PG506 as captured on a LeCroy.

After so many years stuck on Si die I quite enjoy the tactile nature of the old scopes. I enjoy tearing them down, giving a good cleaning, fixing their little problems, and making them live again. I'm sure my interests will evolve as I progress.

Thanks for the inputs.

On Sunday, May 23, 2021, 09:38:51 PM PDT, Mark Goldberg <marklgoldberg@gmail.com> wrote:

Keysight and Tektronix will calibrate anything for anyone that brings
money. They are pretty expensive though. There are good third party
calibration labs, and bad ones. Search for ones with NVLAP or A2LA
accreditation or maybe ANAB accreditation. Compare their uncertainties
(which they should be able to provide) to the desired accuracy for what you
want to calibrate.

I keep a subset of my test equipment calibrated and compare the rest. I get
one Scope / Spectrum Analyzer and one Fluke multimeter done. For frequency,
GPSDOs are so good I don't see any reason to pay for a frequency
calibration of anything, at least for my level of usage. I'm set up to
measure frequency very accurately based on a GPSDO and use one as a
reference for all my test equipment.

New equipment with computer control have automated calibration routines and
are way cheaper to do. Older equipment with lots of pots to turn take a lot
of labor and you will pay more. My MDO3024 Scope / Spectrum Analyzer cost
about $140 to calibrate and my Fluke multimeter about $40 at a third party
lab. The quote for my HP 8642A signal generator was about $300 (lots of
pots to turn). Tektronix wanted about $500 for the scope calibration. I
think they provide big discounts to good customers, but not to me.

Regards,

Mark

On Sun, May 23, 2021 at 9:16 PM Sean Turner <sdturne@q.com> wrote:

Dave,

Time standards are easier than ever now, as there are a plethora of GPSDO
products around. That will be orders of magnitude better than needed for
aligning cathode ray o-scopes. I adjusted the (admittedly crude) Bulova
branded OCXO in my Type 184 to many more decimal places than needed for
scope calibration. I do leave the 184 plugged in at all times so the oven
stays hot.

For DC voltages, you can find things like this:
https://www.ianjohnston.com/index.php/onlineshop/handheld-precision-digital-voltage-source-v2-detail

With a few things like that on hand, you can easily know that a CRO is in
good shape. Probably not sufficient for more accurate instruments that
require incredibly good calibration accuracy (>=6.5 digit meters, spectrum
analyzers, etc), but will serve you fine for oscilloscopes.

As for professional cal services, I do know Keysight will work on
personally owned stuff (and a lot more old HP stuff than you might think, a
lot of that is still in service in pro labs), but get ready to open your
wallet. Especially if you want NIST traceable.

Sean







Re: Getting calibration equipment calibrated

Mark Goldberg
 

Keysight and Tektronix will calibrate anything for anyone that brings
money. They are pretty expensive though. There are good third party
calibration labs, and bad ones. Search for ones with NVLAP or A2LA
accreditation or maybe ANAB accreditation. Compare their uncertainties
(which they should be able to provide) to the desired accuracy for what you
want to calibrate.

I keep a subset of my test equipment calibrated and compare the rest. I get
one Scope / Spectrum Analyzer and one Fluke multimeter done. For frequency,
GPSDOs are so good I don't see any reason to pay for a frequency
calibration of anything, at least for my level of usage. I'm set up to
measure frequency very accurately based on a GPSDO and use one as a
reference for all my test equipment.

New equipment with computer control have automated calibration routines and
are way cheaper to do. Older equipment with lots of pots to turn take a lot
of labor and you will pay more. My MDO3024 Scope / Spectrum Analyzer cost
about $140 to calibrate and my Fluke multimeter about $40 at a third party
lab. The quote for my HP 8642A signal generator was about $300 (lots of
pots to turn). Tektronix wanted about $500 for the scope calibration. I
think they provide big discounts to good customers, but not to me.

Regards,

Mark

On Sun, May 23, 2021 at 9:16 PM Sean Turner <sdturne@q.com> wrote:

Dave,

Time standards are easier than ever now, as there are a plethora of GPSDO
products around. That will be orders of magnitude better than needed for
aligning cathode ray o-scopes. I adjusted the (admittedly crude) Bulova
branded OCXO in my Type 184 to many more decimal places than needed for
scope calibration. I do leave the 184 plugged in at all times so the oven
stays hot.

For DC voltages, you can find things like this:
https://www.ianjohnston.com/index.php/onlineshop/handheld-precision-digital-voltage-source-v2-detail

With a few things like that on hand, you can easily know that a CRO is in
good shape. Probably not sufficient for more accurate instruments that
require incredibly good calibration accuracy (>=6.5 digit meters, spectrum
analyzers, etc), but will serve you fine for oscilloscopes.

As for professional cal services, I do know Keysight will work on
personally owned stuff (and a lot more old HP stuff than you might think, a
lot of that is still in service in pro labs), but get ready to open your
wallet. Especially if you want NIST traceable.

Sean







Re: Getting calibration equipment calibrated

Dave Peterson
 

Hmm,

Seems kind of a mixed bag then. I would love to get my own level and time references setup. I have only superficially heard about using GPS based clocks/timing. Seems this might be my opportunity to learn up on that. And thanks for the level reference link Sean. I'll follow up on that too.

The spectral requirements of the SG503/504 sounds out of my league. When opening up my wallet for a place like Keysight, are we talking 100s? It certainly can't be more than, say, $500 for calibrating one plug-in? Can it? But paying for professional services does get expensive fast.

On Sunday, May 23, 2021, 9:24:27 PM PDT, Eric <ericsp@gmail.com> wrote:

For timing a good (lots of digits) frequency counter hooked to a GPSDO will get you where you need to know then you time reference Is based on the GPS clocks which are HIGHLY accurate. At least WAY more accurate then a 400 series scope at 3%. I did a TG501 and a 184 in my lab with a DMM, Frequency counter, and 100 Mhz scope. There is one adjustment in the 184 that you have to balance 2 trigger points these are the 2 bright spots the should be level.  But the SG503 and 504 need spectral purity characterized as well as the SG503 needs that odd 50 Ohm cable. I have to tare in to my 503 it kind of went nuts on me when I was working on a 465. Sorry for the 2 replies I started this on the small screen and moved to the large one.

Eric

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Dave Peterson via groups.io
Sent: Monday, May 24, 2021 12:06 AM
To: TekScopes@groups.io
Subject: [TekScopes] Getting calibration equipment calibrated

Hi All,

How much does it cost to get PG506s, SG503/SG504s, and TG501s calibrated?

I can certainly search for local calibration facilities, but having no experience at all: do they tend to be amenable to DIYer's, is the cost in the realm of reasonable, is it worth it?

I have a PG506 that's working beautifully, but I can't be certain that the voltage levels are in spec.

The SG503 seems to work, and I can tell pretty well that it's level above 100MHz, but only on an un-calibrated 7854 scope. So while I feel good about the 100MHz scopes I'm testing with it, no one could call that calibrated.

The TG501 is dead, the SG504 blew a fuse when pressed the "ref" button. So those will need some repair. If I can get them working it would be nice to add them to the calibration set.

It'd be really nice to have all four of these officially calibrated. That'd give me assurance that the scopes I'm repairing are properly tuned up. I don't have any means at hand otherwise to verify level or timing. I could keep working on finding means of establishing standards for level and time. But would it just be more cost effective to pay for calibration?



Thanks,
Dave


Re: Getting calibration equipment calibrated

Eric
 

For timing a good (lots of digits) frequency counter hooked to a GPSDO will get you where you need to know then you time reference Is based on the GPS clocks which are HIGHLY accurate. At least WAY more accurate then a 400 series scope at 3%. I did a TG501 and a 184 in my lab with a DMM, Frequency counter, and 100 Mhz scope. There is one adjustment in the 184 that you have to balance 2 trigger points these are the 2 bright spots the should be level. But the SG503 and 504 need spectral purity characterized as well as the SG503 needs that odd 50 Ohm cable. I have to tare in to my 503 it kind of went nuts on me when I was working on a 465. Sorry for the 2 replies I started this on the small screen and moved to the large one.

Eric

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Dave Peterson via groups.io
Sent: Monday, May 24, 2021 12:06 AM
To: TekScopes@groups.io
Subject: [TekScopes] Getting calibration equipment calibrated

Hi All,

How much does it cost to get PG506s, SG503/SG504s, and TG501s calibrated?

I can certainly search for local calibration facilities, but having no experience at all: do they tend to be amenable to DIYer's, is the cost in the realm of reasonable, is it worth it?

I have a PG506 that's working beautifully, but I can't be certain that the voltage levels are in spec.

The SG503 seems to work, and I can tell pretty well that it's level above 100MHz, but only on an un-calibrated 7854 scope. So while I feel good about the 100MHz scopes I'm testing with it, no one could call that calibrated.

The TG501 is dead, the SG504 blew a fuse when pressed the "ref" button. So those will need some repair. If I can get them working it would be nice to add them to the calibration set.

It'd be really nice to have all four of these officially calibrated. That'd give me assurance that the scopes I'm repairing are properly tuned up. I don't have any means at hand otherwise to verify level or timing. I could keep working on finding means of establishing standards for level and time. But would it just be more cost effective to pay for calibration?



Thanks,
Dave


Re: Getting calibration equipment calibrated

Sean Turner
 

Dave,

Time standards are easier than ever now, as there are a plethora of GPSDO products around. That will be orders of magnitude better than needed for aligning cathode ray o-scopes. I adjusted the (admittedly crude) Bulova branded OCXO in my Type 184 to many more decimal places than needed for scope calibration. I do leave the 184 plugged in at all times so the oven stays hot.

For DC voltages, you can find things like this: https://www.ianjohnston.com/index.php/onlineshop/handheld-precision-digital-voltage-source-v2-detail

With a few things like that on hand, you can easily know that a CRO is in good shape. Probably not sufficient for more accurate instruments that require incredibly good calibration accuracy (>=6.5 digit meters, spectrum analyzers, etc), but will serve you fine for oscilloscopes.

As for professional cal services, I do know Keysight will work on personally owned stuff (and a lot more old HP stuff than you might think, a lot of that is still in service in pro labs), but get ready to open your wallet. Especially if you want NIST traceable.

Sean


Re: Getting calibration equipment calibrated

Eric
 

Dave e mail me off list I might be able to help you out there. The
calibrations are not hard just a process... the gear you need for the
calibrations especially the sg503 and 504 are substantial you will need a 1
ghz + spec analyser. Calibrating the pg is not bad it is done at DC until
you get to the fast rise pulses you will need a fast scope 2 ghz + or a
sampling system. I take it from the list of gear you are looking to do a
scope?

Eric

On Mon, May 24, 2021, 12:06 AM Dave Peterson via groups.io <davidpinsf=
yahoo.com@groups.io> wrote:

Hi All,

How much does it cost to get PG506s, SG503/SG504s, and TG501s calibrated?

I can certainly search for local calibration facilities, but having no
experience at all: do they tend to be amenable to DIYer's, is the cost in
the realm of reasonable, is it worth it?

I have a PG506 that's working beautifully, but I can't be certain that the
voltage levels are in spec.

The SG503 seems to work, and I can tell pretty well that it's level above
100MHz, but only on an un-calibrated 7854 scope. So while I feel good about
the 100MHz scopes I'm testing with it, no one could call that calibrated.

The TG501 is dead, the SG504 blew a fuse when pressed the "ref" button. So
those will need some repair. If I can get them working it would be nice to
add them to the calibration set.

It'd be really nice to have all four of these officially calibrated.
That'd give me assurance that the scopes I'm repairing are properly tuned
up. I don't have any means at hand otherwise to verify level or timing. I
could keep working on finding means of establishing standards for level and
time. But would it just be more cost effective to pay for calibration?

Thanks,
Dave






Getting calibration equipment calibrated

Dave Peterson
 

Hi All,

How much does it cost to get PG506s, SG503/SG504s, and TG501s calibrated?

I can certainly search for local calibration facilities, but having no experience at all: do they tend to be amenable to DIYer's, is the cost in the realm of reasonable, is it worth it?

I have a PG506 that's working beautifully, but I can't be certain that the voltage levels are in spec.

The SG503 seems to work, and I can tell pretty well that it's level above 100MHz, but only on an un-calibrated 7854 scope. So while I feel good about the 100MHz scopes I'm testing with it, no one could call that calibrated.

The TG501 is dead, the SG504 blew a fuse when pressed the "ref" button. So those will need some repair. If I can get them working it would be nice to add them to the calibration set.

It'd be really nice to have all four of these officially calibrated. That'd give me assurance that the scopes I'm repairing are properly tuned up. I don't have any means at hand otherwise to verify level or timing. I could keep working on finding means of establishing standards for level and time. But would it just be more cost effective to pay for calibration?

Thanks,
Dave


2465B on a 200C scope cart?

Jeff Keyzer
 

I have a 200C scope cart that I use with my 465B. I'd like to put my 2465B
on the scope cart, but the feet on the 2400 series scope don't line up with
the little plastic cups that keep the scope from sliding off the cart. I
know that at one point Tek suggested that the 200C can be used with the 2400
series scopes. My question is, were there special retaining "cups" for the
2465B to adapt it to the hole pattern on the tray, or did they expect you to
remove the cups, lash the scope to the tray and hope that it doesn't slide
off?


Re: My eye sensitivity to blue-violet higher than normal

Harvey White
 

the shorter the wavelength of the light, the better focus you can get.  One reason why IR images are fuzzy (the other may be a compromise between different focus settings).  Since different colors focus at different distances in a lens, you need to have a camera lens designed for this.  Not at all sure that the human eye takes that into account at all.

Spot size is one reason that the DVD (blue-ray) blue light holds more data than a CD (IR light).

Xrays are used in lithography for most complicated ICs, not visible light, IIRC.

Harvey

On 5/23/2021 11:15 PM, Mark Vincent wrote:
It seems I really started something with my post. Thanks to those that have already replied. Any more would be welcome. I have known of my ability to see the higher frequency colours since I was a kid. I do not have any vision problems. All I know is the better ability to see blue to violet better than anyone I have met. Doctors I have told this to do not know exactly why I see better with these colours. It has to be a DNA feature that is determined in the womb. Other light colours do not bother me. Saying I may be a mutant by Mr. Carsten could be right on. A mutation in the DNA is possible if not likely.

Flicker does annoy me. NOVA had a show years ago titled "Can buildings make you sick". I bought a VHS tape of this after it aired to show people I am not the only one. One segment in that show verified that headaches and eye strain will occur to everyone in varying degrees. They used the typical 60 c/s fluorescent light source and a tungsten light on volunteers. The ones said it was easier to read and see under the latter for any length of time. Electronic ballasts operate so fast, the phosphour in the tube cannot fully decay in its glow like a standard transformer ballast. Now cheap LED lighting uses a half-wave supply. Better is filtered dc. Slowing a trace using any P number will annoy anyone. The slower sweep is needed at times, e.g. 20ms/div. I understand the mesh makes traces thicker no matter what P is on the inside.

For colour rendition, white is best. Read a resistor colour band under some light colours and the bands will look different.

It was found that sound on film had better fidelity when a blue to UV light was used on the soundtrack. The higher frequency of the light the higher audio frequencies be put in without the attenuation. Notice a shadow is sharper as the light source frequency increases. IC lithography uses UV.

I only use the scale illumination when needed. I keep it at minimum otherwise. The graticule is seen easily unless the ambient light level is too low. An EMI shield with a blue trace is no problem for me. Trace/readout intensity is kept as low as possible to see. The 7104 is barely visible until the trace is needed to be seen then brought up enough to see while keeping the yellow LED off then intensity back down. This is when I use that model. The crt in this is good, not weak by any means. Protect the MCP.

Mr. Gentry makes me wish convergence was still done. I miss NTSC and delta guns. Here is something for TV history people, Electronicam.

I have noticed the 2000 series never had Opt. 78.

Blue eyed people have less melanin. The mention of the WW2 navy using UV is interesting.

Thanks again for the replies. Anyone else is welcome. I have already learned things.

Mark





Re: My eye sensitivity to blue-violet higher than normal

Mark Vincent
 

It seems I really started something with my post. Thanks to those that have already replied. Any more would be welcome. I have known of my ability to see the higher frequency colours since I was a kid. I do not have any vision problems. All I know is the better ability to see blue to violet better than anyone I have met. Doctors I have told this to do not know exactly why I see better with these colours. It has to be a DNA feature that is determined in the womb. Other light colours do not bother me. Saying I may be a mutant by Mr. Carsten could be right on. A mutation in the DNA is possible if not likely.

Flicker does annoy me. NOVA had a show years ago titled "Can buildings make you sick". I bought a VHS tape of this after it aired to show people I am not the only one. One segment in that show verified that headaches and eye strain will occur to everyone in varying degrees. They used the typical 60 c/s fluorescent light source and a tungsten light on volunteers. The ones said it was easier to read and see under the latter for any length of time. Electronic ballasts operate so fast, the phosphour in the tube cannot fully decay in its glow like a standard transformer ballast. Now cheap LED lighting uses a half-wave supply. Better is filtered dc. Slowing a trace using any P number will annoy anyone. The slower sweep is needed at times, e.g. 20ms/div. I understand the mesh makes traces thicker no matter what P is on the inside.

For colour rendition, white is best. Read a resistor colour band under some light colours and the bands will look different.

It was found that sound on film had better fidelity when a blue to UV light was used on the soundtrack. The higher frequency of the light the higher audio frequencies be put in without the attenuation. Notice a shadow is sharper as the light source frequency increases. IC lithography uses UV.

I only use the scale illumination when needed. I keep it at minimum otherwise. The graticule is seen easily unless the ambient light level is too low. An EMI shield with a blue trace is no problem for me. Trace/readout intensity is kept as low as possible to see. The 7104 is barely visible until the trace is needed to be seen then brought up enough to see while keeping the yellow LED off then intensity back down. This is when I use that model. The crt in this is good, not weak by any means. Protect the MCP.

Mr. Gentry makes me wish convergence was still done. I miss NTSC and delta guns. Here is something for TV history people, Electronicam.

I have noticed the 2000 series never had Opt. 78.

Blue eyed people have less melanin. The mention of the WW2 navy using UV is interesting.

Thanks again for the replies. Anyone else is welcome. I have already learned things.

Mark


Re: Has anyone replaced the Graticule lights with LEDs?

Eric
 

Led moding a 7000 Series Scope after crawling in to my head from a year ago.

The LEDs used were Adafruit / 754 Super bright White Leds. Important notes on these Vforward for the diode being white is 2.5Vdc this is important later. Led Size is 5mm Clear

Dropping resister – None

Power supply open circuit voltage – 8.1 Vdc at full illumination

LED wiring parallel like the old light bulbs

The lamp illumination is current limited by the scope its self. When the LEDs are connected and the illumination on FULL the voltage across the connector in the scope is only 3.2 Vdc this means that the Leds are only drawing about 40mA each this was verified on a 577. This is why the leds don’t burn up with no current limiting resister. This is running the leds at about 2X design spec but after running one like this off a lab power supply for a few hours it is barely warm to the touch and has not moved from a round 0.031 mA current draw Amp meter in the power supply so not the best thing in the word for measurement.

Eric

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Harvey White
Sent: Sunday, May 23, 2021 6:31 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Has anyone replaced the Graticule lights with LEDs?

LEDs can be gotten in different dispersions, some, for instance, I think at 130 degrees. If you have a 3D printer, you might be able to make a light shroud depending on your needs. If you can do PC boards, then I could recommend a 3 color LED. How to profitably control it is another matter. Otherwise, pick a color depending on what you want.

It might get close to an incandescent lamp.

Harvey


On 5/23/2021 5:15 PM, DaveH52 wrote:
In a few days, I'll be disassembling my 2465 again to install a replacement module for U800. Since it will be totally disassembled, I'm seriously considering replacing the graticule lamps with red LEDs. I plan on 'frosting' the tops so the light will be more diffused. It worked well for the meter on my Kenwood TS-440, except I used white LEDs for that.






Re: My eye sensitivity to blue-violet higher than normal

stevenhorii
 

This may seem crazy, but blue irises are not actually pigmented blue. They
are non-pigmented. The blue color is due to the Tyndall effect (light
scattering). See this:

https://www.aao.org/eye-health/tips-prevention/your-blue-eyes-arent-really-blue

Those with brown eyes have melanin pigment in their irises, so they are
actually brown in color.

There is some evidence that those with blue eyes are more light sensitive
overall, and light may not only scatter, but may pass through even the part
of the iris that is “closed” (i.e., not the pupil) because there is no
pigment to absorb as much light. I know two people, both men with blue
eyes, who claimed to have increased sensitivity to blue light and were
bothered by the blue lights that are sometimes used to indicate the
location of emergency call boxes. I was with them on more than one occasion
when they would shield their eyes from blue light sources (those call box
lights, blue neon signs, blue flashing emergency lights, etc). I never did
understand why they had this, but this article (oriented to
ophthalmologists and other physicians) discusses some of this as well as
the relationship with migraines and the possible causes:

https://www.aao.org/eyenet/article/md-roundtable-solving-photophobia-puzzle

Maybe that lack of iris pigment?

I hope the information is useful.

Steve Horii (I am a physician, but not an ophthalmologist)

On Sun, May 23, 2021 at 19:35 Mark Vincent <orangeglowaudio@gmail.com>
wrote:

I would like to know from anyone in this group that has a good educated to
known medical reason why I have a higher sensitivity and ease of viewing
light that is blue to violet so easily. I understand the rods and cones in
the eye and have enough medical knowledge to understand the Latin and Greek
terms of medical words. I have NO problem in seeing, focusing or any form
of eye strain on light that is in the high frequency part of the spectrum
of blue to violet, including indigo. I have always been this way. One note,
I do have blue eyes if that makes any difference. They are not the striking
steel blue that can look like blue lasers. Jean Harlow had steel blue eyes,
as an example of someone. Blue/ steel blue eyes in a male is far more
common in a male than a female.

Another thing I have with my eyes is that under 50/60 c/s flicker, I will
get a severe migraine and have the vision of "Mr. Magoo" within a few
minutes that takes a few hours to wear off after being removed from the
flickering light(s). For reading and general lighting, I prefer carbon
filament (Ferrowatt). Tungsten is fine.

Brenda mentioned having a RM565 scope with a blue trace (must be P11 by the
model) that she gets eye strain easily. This is what finally made me ask
the group this. Others have mentioned how P11, blue, is nice briefly, not
for any time without the owner having eye strain and hard to focus on. I
have seen older posts on this group and other places online about people
saying blue trace is nice but annoyed by the hard to focus on and eye
strain within a few minutes. I have a couple of friends with blue eyes that
I asked about blue-violet phosphour. They said it is nice to glance at or
for a short time, not for any longer. They said they would prefer P1, P31,
etc, that is in the green area to look at for any length of time, a minute
or more. I will deal with P1 or P31. I find P2 the WORST to look at. The
blue part is fine, the cyan afterglow I find bilious. P7 is not as bad as
the afterglow is yellow with only the blue seen with a proper filter. Even
so, I will keep the intensity of a P7 low so as to only see the blue.

I know storage types need a P31 because of the secondary emission.
Something like the 2467/B or 7104 with the MCP could have been made with
other phosphours when made. The MCP does not care about the phosphour, only
acting like a photomultiplier.

I would like to find the P11 crts for my 556, 7603 and 465. The P31s in
them are in very good condition. I prefer the P11 because of the thinner
trace, ease on my eyes. and faster decay time. To find a 502A with P11 and
T317P11 for my 317 would be great. I know the 502A is 2mc capacity. The
7000 series I have, except for the 7934 and 7104, now have the P11 in them.
I do have good P31 types I removed from the scopes sitting around. I do
have a few of the 300, 400 and 500 series with the P11. If I can find
someone who can successfully rewind the high voltage transformers for the
older types, I would really like P11 for me 545B and 547 after getting
these transformers rewound. The only thing I have seen P16 in is a B&K 1076
analyst. That colour does not bother me at all. So far I have not seen a P5
although having any of these, 3AP5 for example, in place of a P1 would be
great. I know the decay time and light output of P5 is less and P11.

For any plant that has flowers, I do not mind any colour.

Mark






Re: Happy birthday Bob Moog

Tom Lee
 

Hi Carsten,

It looks like a 465. The two models differ subtly in the colored highlighting of the highest-speed sweep ranges. You can barely make out the shape here, but enough, I think,  to match it to the 465.

-- MfG,
Tom

--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
http://www-smirc.stanford.edu

On 5/23/2021 18:34, Carsten Bormann wrote:
On 2021-05-24, at 02:54, toby@telegraphics.com.au wrote:
https://twitter.com/moogmusicinc/status/1396441500226101249
So what exactly is the Tek scope in the image? 475?

I recognize the HP 400GL(?) at the top of the shelf.

(Maybe there is a higher resolution version of that picture somewhere…)

Grüße, Carsten





Re: Happy birthday Bob Moog

Carsten Bormann
 

On 2021-05-24, at 02:54, toby@telegraphics.com.au wrote:

https://twitter.com/moogmusicinc/status/1396441500226101249
So what exactly is the Tek scope in the image? 475?

I recognize the HP 400GL(?) at the top of the shelf.

(Maybe there is a higher resolution version of that picture somewhere…)

Grüße, Carsten


Re: Happy birthday Bob Moog

Jeff Davis
 

Thanks, Toby

On May 23, 2021, at 6:12 PM, toby@telegraphics.com.au wrote:

On 2021-05-23 9:00 p.m., Jeff Davis wrote:
I feel certain this is legitimate and sent with the best of intentions. However, for every one like that, I get at least 50 that are nothing more than phishing campaigns trying to get me to click on a malware link.

I’m wondering if there might be a safer way to make this available to the group?
Sure. It's just a safe link to a tweet. If you don't like the automatic
linking, you can recreate the URL from this:

twitter dot com/moogmusicinc/status/1396441500226101249

Anyone not comfortable viewing a tweet, ignore.

--Toby

Regards,
Jeff/N0DY
On May 23, 2021, at 5:54 PM, toby@telegraphics.com.au wrote:
Hi list,

Click for a nice surprise.

https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftwitter.com%2Fmoogmusicinc%2Fstatus%2F1396441500226101249&;data=04%7C01%7C%7Cba5219f4da8b4fcda10508d91e50f18c%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637574155262188335%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=XYhgc73OFLhWNqYaCu8KhtFCbSW24oYo8CUY4jxOCYk%3D&amp;reserved=0

--Toby












Re: My eye sensitivity to blue-violet higher than normal

Carsten Bormann
 

On 2021-05-24, at 01:34, Mark Vincent wrote:

I would like to know from anyone in this group that has a good educated to
known medical reason why I have a higher sensitivity and ease of viewing
light that is blue to violet so easily. I understand the rods and cones in
the eye and have enough medical knowledge to understand the Latin and Greek
terms of medical words. I have NO problem in seeing, focusing or any form
of eye strain on light that is in the high frequency part of the spectrum
of blue to violet, including indigo.
Well, you’re a mutant then.
(I’m not joking; you might very well be [2].)
Any other anomalies in your color vision?

Let me explain what is really special about the blue-sensitive cones:
Only about 2 % of our cones are of that kind [1]. That is enough for our eyes to be quite *sensitive* to blue light, but it gives a much lower *resolution* for blue light than for the green-to-red part of the spectrum.

That is why it is harder to resolve fine details in blue-on-black or yellow-on-white or any other contrast that differs only in the blue part of the spectrum. As long as the features are big, no problem. But at some point the small number of blue-sensitive cones just doesn’t have the resolution we are used to having for green-to-red.

I have no comment on your other observations, but when it comes to average human vision in the blue spectrum, it is important to distinguish sensitivity (which is great) from resolution (which is poor).

Grüße, Carsten

[1]: https://en.wikipedia.org/wiki/Cone_cell#Types
[2]: https://en.wikipedia.org/wiki/Tetrachromacy#Humans


Re: Happy birthday Bob Moog

toby@...
 

On 2021-05-23 9:00 p.m., Jeff Davis wrote:
I feel certain this is legitimate and sent with the best of intentions. However, for every one like that, I get at least 50 that are nothing more than phishing campaigns trying to get me to click on a malware link.

I’m wondering if there might be a safer way to make this available to the group?
Sure. It's just a safe link to a tweet. If you don't like the automatic
linking, you can recreate the URL from this:

twitter dot com/moogmusicinc/status/1396441500226101249

Anyone not comfortable viewing a tweet, ignore.

--Toby

Regards,
Jeff/N0DY
On May 23, 2021, at 5:54 PM, toby@telegraphics.com.au wrote:

Hi list,

Click for a nice surprise.

https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftwitter.com%2Fmoogmusicinc%2Fstatus%2F1396441500226101249&;data=04%7C01%7C%7C1158d649c4d74a50840308d91e4e853c%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637574144847409180%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=k5pDK8VTiiYgwYBCTbz5JZFvHfXadv3Rkb0Xuo7waow%3D&amp;reserved=0

--Toby








Re: Happy birthday Bob Moog

greenboxmaven
 

His accomplishments were incredible. Perry & Kingsley, Dick Hyman, and Wendy Carlos made exceptional music on his instruments. For another type of synthesis, this time visual, also in Asheville, make an internet search for "Scanimate".  A lifelong friend has perhaps the last two of them in existence in his studio there. I am not sure if he ever met Bob Moog, but like me, he liked the music produced on synthesizers.

  Bruce Gentry, KA2IVY

On 5/23/21 20:54, toby@telegraphics.com.au wrote:
Hi list,

Click for a nice surprise.

https://twitter.com/moogmusicinc/status/1396441500226101249

--Toby




Re: Happy birthday Bob Moog

Jeff Davis
 

I feel certain this is legitimate and sent with the best of intentions. However, for every one like that, I get at least 50 that are nothing more than phishing campaigns trying to get me to click on a malware link.

I’m wondering if there might be a safer way to make this available to the group?

Regards,
Jeff/N0DY

On May 23, 2021, at 5:54 PM, toby@telegraphics.com.au wrote:

Hi list,

Click for a nice surprise.

https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftwitter.com%2Fmoogmusicinc%2Fstatus%2F1396441500226101249&;data=04%7C01%7C%7C1158d649c4d74a50840308d91e4e853c%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637574144847409180%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=k5pDK8VTiiYgwYBCTbz5JZFvHfXadv3Rkb0Xuo7waow%3D&amp;reserved=0

--Toby




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