Date   
Re: Tektronix Type 575 Transistor Curve Tracer - $75 (Syracuse)

Glydeck
 

Tam,
Here is the Craig's list info;
contact name:
Ron
call
☎ (315) 446-5064
reply by email:
6gt28-6421973174@...
webmail links:
gmail
yahoo mail
hotmail, outlook, live mail
aol mail
copy and paste into your email:
6gt28-6421973174@...

Sent from my iPad

On Dec 13, 2017, at 2:47 PM, @neff1942 [TekScopes] <TekScopes@...> wrote:

Hi Tam,

If you cannot get that one I have one that is in excellent working condition for 175.00.

73,

Bill, WA2DVU

Cape May, NJ

From: TekScopes@... [mailto:TekScopes@...]
Sent: Wednesday, December 13, 2017 10:12 AM
To: TekScopes@...
Subject: [TekScopes] Re: Tektronix Type 575 Transistor Curve Tracer - $75 (Syracuse)

Hello,

tried to get the guys email addy, but the Craigslist web site is not
willing to let me in.

I would gladly pay for shipping. The 575 is the last of the Danaher
curve tracers I still miss for my upgrade project.

Tam

--
With best regards
Tam Hanna
---

NEW: Enjoy electronics? Like seeing oscilloscopes get repaired? Please subscribe to my new YouTube channel -> http://www.youtube.com/user/MrTamhan

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Re: Deane Kidd and the Metric System

Tom Jobe <tomjobe@...>
 

I've been enjoying this excellent 'off topic' discussion of oddities and
historical facts about these currencies!
I too thought the US dollar coins were just an unused oddity, but now
they are using those dollar coins to give you change when you buy a
MetroLink commuter train ticket from a vending machine at a train
station here in Southern California. For example, you can put in a $20
paper bill and get all coins as your change for a few dollar ticket
purchase.
The first time this happened to me, I thought I would never be able to
get rid of the hand full of odd dollar coins I had received as change,
but they were accepted without comment when I used the coins to pay for
other things at other places. The US dollar coin usage must be more
common than I thought.
tom jobe...

On 12/13/2017 4:47 PM, Dave Seiter d.seiter@... [TekScopes] wrote:

Dennis, you forgot the Anthony and Sacagawea dollar coins, the later
is still minted.
-Dave

From: "'Dennis Tillman' @Dennis_Tillman_W7pF [TekScopes]"
<TekScopes@...>
To: TekScopes@...
Sent: Wednesday, December 13, 2017 3:05 PM
Subject: RE: [TekScopes] Deane Kidd and the Metric System

  About once a week my wife asks me a question which goes something
like this:
The recipe calls for 1 teaspoon of xxx per 8oz of yyy, how many ounces of
xxx do I need if I'm making two gallons of yyy?

Our paper currency is metric, but our coinage is a throwback to older
times
and it is starting to change as pennies are becoming too worthless to be
bothered with in many cases. As to the rest consider this mess:
* There are five pennies in a nickel
* There are two nickels in a dime
* There are five nickels (or 25 pennies) in a quarter.
* A quarter is a quarter (1/4) of a dollar so there are four in a dollar
* A bit was 1/8th of a dollar so a quarter is also known as "two
bits". This
goes back to when the dominant currency was the Spanish dollar (also known
as pieces of eight) which was worth 8 Spanish silver reales. One reale was
one bit.
* A half dollar (a coin most people would rather not have in their pocket
because of its weight) is worth two quarters, four bits, five dimes, ten
nickels, or 50 pennies.
* A dollar is made up of 20 nickels, 10 dimes, 4 quarters, 2 fifty-cent
pieces or any combination that adds up to 100 pennies. Most dollars are
paper but there are silver dollar coins as well although the mint stopped
making them a long time ago so they are more of a collector's item.

Thank goodness we don't have the Looney (the Canadian $2 coin). We do have
the $2 bill but it is not in common usage. It is more a novelty. Some
people
believe it is unlucky to receive one.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: Tuesday, December 12, 2017 11:13 PM
To: TekScopes@...
Subject: RE: [TekScopes] Deane Kidd and the Metric System

Subject: [TekScopes] Deane Kidd and the Metric System
Metrification would have been a nightmare for Deane had it survived.
I'm sure Deane breathed a
sigh
of relief when the metrification of the US fizzled shortly after it
started.

Dennis Tillman W7PF
That is a very interesting story Dennis. It must have come as a shock when
you touched Deane's nerve. But oddly you have had metric currency for a
whole lot longer than we have in the UK.

But of course, we in the UK went through the whole metrication process.
However it was more protracted than I remember
https://en.wikipedia.org/wiki/Metrication_in_the_United_Kingdom , which is
why it is a success, and full of imperial hangovers that I mentioned in an
earlier post.

The last metric bastion for me, and this is recently, is navigation by map
and compass. I used to estimate in miles distance and feet of elevation
gained. Then someone who I respect said "What on earth are you doing that
for? Ordnance Survey maps are divided into kilometre squares, and the
contours are in either 5 or 10 metre intervals". Ding - the light went on.

Craig

------------------------------------
Posted by: "Craig Sawyers" <c.sawyers@...>
------------------------------------

------------------------------------

Yahoo Groups Links

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Re: c-12 camera

 

You could probably find a plastic flower pot which will fit over the scope's bezel.With a chassis punch, enlarge the hole in the bottom of the pot so your camera lens will fit it.
Voila . . . a camera adapter !
 HankC, Boston WA1HOS

Re: c-12 camera

Chuck Harris
 

I would have to dig mine out to find out its model, I think
C51, but it is an f1.2 lens, with about 0.8 magnification,
I recall that the photos of a 7633 were a little smaller than
a full frame for the poloroid roll film it used. 1.2x would
have fit the scope's screen better. I think it was meant for
the 7904.

-Chuck Harris

'Craig Sawyers' c.sawyers@... [TekScopes] wrote:

I sold my Tek C53 camera, but I'd be interested to know what is in the lens. Looking at web images,
the lenses seem to be about f/2 with a magnification range of 0.7 to 1.5. But their resolution did not
have to be so good, because of the finite size of the trace and graticule. If the graticule lines are
(say) 0.1mm (4 mil) and the screen is 10 x 8cm, you only need 1000 points across the screen to resolve
the graticule lines, and considerably less than that for the trace and readout. In fact Tek made a
digital camera, the C1002 which had 728 x 490 pixels - which is consistent with the estimate of 1000
pixels across the screen to resolve the graticule. I have one, and it gets occasional use. Works just
fine. The only negative is that it free-runs and has no trigger facility either in or out, so it is
useless in taking an image of a single shot.

Nowadays a half way decent mobile can resolve 3600 (12M-pixel) points, and a DSLR - well it depends on
how much you pay.

I pretty much always use my phone now, just handheld. The only difficulty is minimising reflections
from the screen.

Craig

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: 14 December 2017 11:16
To: TekScopes@...
Subject: RE: [TekScopes] Re: c-12 camera

Petzval curvature is actually independent of the conjugates.

Phosphor emission is narrowband but far from monochromatic.

Some form of chromatic aberration correction of the lens will be necessary.

Bruce

On 14 December 2017 at 21:36 "'Craig Sawyers' c.sawyers@... [TekScopes]"
<TekScopes@...> wrote:



> I would think the lens would make a nice enlarger lens...
> flat field, very fast...
>
> -Chuck Harris

I don't think so Chuck. They are optically designed for very close to unity magnification, and
hence
unity conjugates, and monochrome. If you use them for much higher magnification they will be
nothing
like flat field, and will be beset with just about every aberration in the book. Even worse if
you use
them for colour.

Craig











------------------------------------
Posted by: Bruce Griffiths <bruce.griffiths@...>
------------------------------------


------------------------------------

Yahoo Groups Links




------------------------------------
Posted by: "Craig Sawyers" <c.sawyers@...>
------------------------------------


------------------------------------

Yahoo Groups Links



Re: c-12 camera

Chuck Harris
 

I am pretty sure that you are wrong about that! Prices
for high end enlargers are about the same today as they
have always been. I checked out my Bessler 23CII on ebay,
thinking of selling it, and found that the used price was
the same today as it was 30 years ago when I bought it.

I expect that you are right about scope cameras, though.
I shot my last polaroid scope picture in the mid 1980's.

-Chuck Harris

Artek Manuals manuals@... [TekScopes] wrote:

Besides almost no one uses enlargers anymore ...for that matter almost
no one uses scope cameras anymore :-)
Dave
manuals@...

Re: c-12 camera

Chuck Harris
 

Ok,

Lens optics was never one of my strengths. I am pretty
good at using them, but have always been a bit befuddled
understanding them. Yes, I could run the numbers, and
get good grades when tested, but I never really internalized
the subject.

How about we just say they are shiny and pretty?

-Chuck Harris

'Craig Sawyers' c.sawyers@... [TekScopes] wrote:

I would think the lens would make a nice enlarger lens...
flat field, very fast...

-Chuck Harris
I don't think so Chuck. They are optically designed for very close to unity magnification, and hence
unity conjugates, and monochrome. If you use them for much higher magnification they will be nothing
like flat field, and will be beset with just about every aberration in the book. Even worse if you use
them for colour.

Craig

Re: c-12 camera

 

I usually resample my graticule photographs down to 900x720 and they
look fine.

At least on my Canon SX150, the 4320 x 3240 sensor has higher
resolution than the lenses can support. Automatic exposure under dark
conditions without ambient room lighting is a problem but a manual
exposure might solve that. I get the best results with diffuse
ambient lighting bright enough to reveal the graticule lines; so far
this has worked better than using the oscilloscope's built in
graticule illumination which tends to fog the area adjacent to the
bulbs but again, a manual exposure might solve that.

On Thu, 14 Dec 2017 13:30:46 -0000, you wrote:

I sold my Tek C53 camera, but I'd be interested to know what is in the lens. Looking at web images,
the lenses seem to be about f/2 with a magnification range of 0.7 to 1.5. But their resolution did not
have to be so good, because of the finite size of the trace and graticule. If the graticule lines are
(say) 0.1mm (4 mil) and the screen is 10 x 8cm, you only need 1000 points across the screen to resolve
the graticule lines, and considerably less than that for the trace and readout. In fact Tek made a
digital camera, the C1002 which had 728 x 490 pixels - which is consistent with the estimate of 1000
pixels across the screen to resolve the graticule. I have one, and it gets occasional use. Works just
fine. The only negative is that it free-runs and has no trigger facility either in or out, so it is
useless in taking an image of a single shot.

Nowadays a half way decent mobile can resolve 3600 (12M-pixel) points, and a DSLR - well it depends on
how much you pay.

I pretty much always use my phone now, just handheld. The only difficulty is minimising reflections
from the screen.

Craig

Re: c-12 camera

 

The C-12 mount for the 500 series is hinged with slots for the pins on
the left side so the heavy camera may be swung out of the way and
lifted off. Here is a photograph of the equally heavy mount as it
came on my 547:

<https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/567122000/lightbox/1422396866#zax/1422396866>

On 14 Dec 2017 02:51:28 +0000, you wrote:

If the C-12 is for 500 series, then the unit pictured is missing the CRT bezel mount too - I don't see anything there that looks like it could hook to a scope of any kind, actually. The mount is probably still attached to whatever scope the camera was used on, if it still exists.

Ed

Re: c-12 camera

Chris Trask - N7ZWY/WDX3HLB
 

That seems to be the case. I liked the later Tektronix cameras, but used an HP instead for years. I had to be careful to not turn on the illuminator when using it on a Tek 'scope.


Good grief, so just as I want to actually use a scope camera, they've
become a hipster fashion accessory?
Chris

When the going gets weird, the weird turn pro
- Hunter S. Thompson

Re: c-12 camera

 

On 14 Dec 2017 01:51:59 +0000, you wrote:

That one shown is a way over-priced (by 25-50x) hulk of a camera, and I think it's too new to fit the old 500 series round bezels anyway - and I think it's missing some parts too (the Polaroid film back, for one). You may be able to find the right kind of CRT mount eventually, but it's easier to find the more modern kind that hang from the slot in the top of the rectangular bezel. You can rig up some sort of adapter to fit the oldies, with banana plug mounts, or a flange to replace the bezel for picture taking.
My 547 came with the C-12 camera so I have the mount for a 500 series
also. The camera is really heavy.

With patience you should look for a nice light weight C-5 type for cheap ($5-10) or free. I've collected a few over the years. On the first one I ripped out the film back, lens, and flash, and mounted a USB PC camera. One of these days I plan to do the same with another, but instead of an attached USB camera, it will have a little mounting shelf on it to hold a phone-camera in the right position - no wires or PC needed, except to get the shots out of the phone later. For the oldies, you can probably just hold a modified C-5 against the front of the scope to steady it and space it properly.

With a steady hand and subdued lighting, you don't even need a camera box to get pretty decent screen shots.

Ed
I have gotten the best results with room lighting if I can keep glare
and shadows off of the CRT face. Otherwise my camera has problems
with exposure and color correction.

Re: c-12 camera

Craig Sawyers <c.sawyers@...>
 

I sold my Tek C53 camera, but I'd be interested to know what is in the lens. Looking at web images,
the lenses seem to be about f/2 with a magnification range of 0.7 to 1.5. But their resolution did not
have to be so good, because of the finite size of the trace and graticule. If the graticule lines are
(say) 0.1mm (4 mil) and the screen is 10 x 8cm, you only need 1000 points across the screen to resolve
the graticule lines, and considerably less than that for the trace and readout. In fact Tek made a
digital camera, the C1002 which had 728 x 490 pixels - which is consistent with the estimate of 1000
pixels across the screen to resolve the graticule. I have one, and it gets occasional use. Works just
fine. The only negative is that it free-runs and has no trigger facility either in or out, so it is
useless in taking an image of a single shot.

Nowadays a half way decent mobile can resolve 3600 (12M-pixel) points, and a DSLR - well it depends on
how much you pay.

I pretty much always use my phone now, just handheld. The only difficulty is minimising reflections
from the screen.

Craig

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: 14 December 2017 11:16
To: TekScopes@...
Subject: RE: [TekScopes] Re: c-12 camera

Petzval curvature is actually independent of the conjugates.

Phosphor emission is narrowband but far from monochromatic.

Some form of chromatic aberration correction of the lens will be necessary.

Bruce

On 14 December 2017 at 21:36 "'Craig Sawyers' c.sawyers@... [TekScopes]"
<TekScopes@...> wrote:



> I would think the lens would make a nice enlarger lens...
> flat field, very fast...
>
> -Chuck Harris

I don't think so Chuck. They are optically designed for very close to unity magnification, and
hence
unity conjugates, and monochrome. If you use them for much higher magnification they will be
nothing
like flat field, and will be beset with just about every aberration in the book. Even worse if
you use
them for colour.

Craig











------------------------------------
Posted by: Bruce Griffiths <bruce.griffiths@...>
------------------------------------


------------------------------------

Yahoo Groups Links


Re: Deane Kidd and the Metric System

n4buq
 

Instead of a ruler for size comparison, perhaps Walter can post pictures of those knobs alongside an assortment of coins from all around the world? :)

Thanks,
Barry - N4BUQ

Re: c-12 camera

Scott McGrath
 

For those of us who are large format photographers as well as engineers many of us stocked up on polaroid 4x5 film because it had many unique qualities.

And it was expensive (3-4 dollars sheet) when it was last being produced by Polaroid

The New55 film is on par with the old Polaroid pricing. You can buy the upgraded 4x5 holders from the project or send yours in for an upgrade. The old 545 holders did have some nagging issues which the New55 people have corrected

As for use by 'hipsters' no not quite as large format photography requires considerable technical skill to even get a usable image. And it requires a large rigid tripod and patience and the ability to use a exposure meter intelligently, for advanced practitioners use of the 'Zone System' is common

None of those things are in the hipster wheelhouse.

What I've thought of doing is modifying a cooled astronomical camera for use in capturing single shot images from 7104. Has the high sensitivity required and is designed for flat field imaging, optics will be tricky though

Looking for MR501 CRT

Szabolcs Szigeti
 

Hi,

I've been working on getting an MR501 to operate, but once I found that the CRT heater shows infinite resistance, I don't think there is any point in going further.
Which is a pity, because I have an RG501 and an SC501 so I could put 2 tiny scopes into a TM503, which would definitely be fun.

If anyone would have a CRT (part no 154-0703-00) for sale, (preferably in Europe for postage cost reasons), I'd be happy to hear from. Interestingly, the CRTs for the MR501 and the SC501 have different part numbers. I'm wondering if they are really different.

Thanks,

Szabolcs

Re: Tek CRTs may not be metric after all

stefan_trethan
 

Didn't Danaher split off Tek and Fluke into a new company some time ago?

ST


On Thu, Dec 14, 2017 at 1:55 PM, Tam Hanna tamhan@...
[TekScopes] <TekScopes@...> wrote:
Hello,

Danaher 577: approx 1.25mm

Danaher 576: approx 1mm


Tolerance +- 1mm, measured it with a ruler which was too big to lay on
the CRT properly.

--
With best regards
Tam Hanna
---

NEW: Enjoy electronics? Like seeing oscilloscopes get repaired? Please subscribe to my new YouTube channel -> http://www.youtube.com/user/MrTamhan

Re: Tek CRTs may not be metric after all

Tam Hanna
 

Hello,

Danaher 577: approx 1.25mm

Danaher 576: approx 1mm


Tolerance +- 1mm, measured it with a ruler which was too big to lay on the CRT properly.

--
With best regards
Tam Hanna
---

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Re: c-12 camera

Bruce Griffiths
 

Petzval curvature is actually independent of the conjugates.

Phosphor emission is narrowband but far from monochromatic.

Some form of chromatic aberration correction of the lens will be necessary.

Bruce

On 14 December 2017 at 21:36 "'Craig Sawyers' c.sawyers@... [TekScopes]" <TekScopes@...> wrote:



> I would think the lens would make a nice enlarger lens...
> flat field, very fast...
>
> -Chuck Harris

I don't think so Chuck. They are optically designed for very close to unity magnification, and hence
unity conjugates, and monochrome. If you use them for much higher magnification they will be nothing
like flat field, and will be beset with just about every aberration in the book. Even worse if you use
them for colour.

Craig







[Non-text portions of this message have been removed]

Re: Deane Kidd and the Metric System

Chris van Lint
 

Right up until the hand-over in 1999, we had
HK$00.01 notes (1 cent) in Hong Kong. They were
printed on one side only, because the printing
costs exceeded the value of the note. They were
not used in general transactions, but were there
for accounting purposes, when settlement of
transactions had to be exact to the cent.

At 07:38 PM 14/12/2017, you wrote:


The UK still mints several unusual coins which - importantly - can
be used in supermarkets. They are quite popular for several
reasons:
- since they are "coins of the realm", it would be difficult
for the exchequer to levy capital gains tax
- their gold street value is a hedge against market
instabilities
- they are rare and pretty

The sovereign, with a face value of £1. It is 7.98805g and
contains 7.322381g of gold (22carat). There are 1/2 and 1/4
sovereign variants.

The britannia, with a face value of £100. Until 2012 they
were 31.104g and contained 34.050g of gold (22 carat).
Now they are 24 carat. They have 5, 1/4, 1/10, 1/20 variants.

On 14/12/17 03:29, David @DWH [TekScopes] wrote:

On Wed, 13 Dec 2017 11:50:25 -0000, you wrote:

Half dollars, quarters, and nickels divide
dollars into halves, quarters,
and twentieths.

Posted by: David <@DWH>
Well yes, but you have 100 pennies to the
dollar, same as us to the pound.
But we have other coins
too. The 2p(fiftieth), 5p (twentieth),
10p(tenth) 20p(fifth) and 50p(half)
and £2(twice). There was
at one stage a 25p coin too (quarter). That doesn't make either you or us
non-decimal for currency.
We just divide our decimal base currency whether US dollars or pounds
sterling into convenient
chunks.

...

Even for those like me who were brought up
with that system until age 15, it
was complete madness.
Doing mental arithmetic with it was a nightmare.

Craig
The part I like is that when dimes, quarters, half dollars, and dollar
coins were silver, they all had a weight proportional to their value
so they could simply be weighed instead of counted.

This does not work anymore because dimes come in two different
weights.

Re: Deane Kidd and the Metric System

Tom Gardner
 

The UK still mints several unusual coins which - importantly - can
be used in supermarkets. They are quite popular for several
reasons:
- since they are "coins of the realm", it would be difficult
for the exchequer to levy capital gains tax
- their gold street value is a hedge against market
instabilities
- they are rare and pretty


The sovereign, with a face value of �1. It is 7.98805g and
contains 7.322381g of gold (22carat). There are 1/2 and 1/4
sovereign variants.

The britannia, with a face value of �100. Until 2012 they
were 31.104g and contained 34.050g of gold (22 carat).
Now they are 24 carat. They have 5, 1/4, 1/10, 1/20 variants.

On 14/12/17 03:29, David @DWH [TekScopes] wrote:

On Wed, 13 Dec 2017 11:50:25 -0000, you wrote:

Half dollars, quarters, and nickels divide dollars into halves, quarters,
and twentieths.

Posted by: David <@DWH>
Well yes, but you have 100 pennies to the dollar, same as us to the pound.
But we have other coins
too. The 2p(fiftieth), 5p (twentieth), 10p(tenth) 20p(fifth) and 50p(half)
and �2(twice). There was
at one stage a 25p coin too (quarter). That doesn't make either you or us
non-decimal for currency.
We just divide our decimal base currency whether US dollars or pounds
sterling into convenient
chunks.

...

Even for those like me who were brought up with that system until age 15, it
was complete madness.
Doing mental arithmetic with it was a nightmare.

Craig
The part I like is that when dimes, quarters, half dollars, and dollar
coins were silver, they all had a weight proportional to their value
so they could simply be weighed instead of counted.

This does not work anymore because dimes come in two different
weights.

Re: c-12 camera

ArtekManuals
 

Besides almost no one uses enlargers anymore ...for that matter almost
no one uses scope cameras anymore :-)
Dave
manuals@...

On 12/14/2017 3:36 AM, 'Craig Sawyers' c.sawyers@...
[TekScopes] wrote:

I would think the lens would make a nice enlarger lens...
flat field, very fast...

-Chuck Harris
I don't think so Chuck. They are optically designed for very close to
unity magnification, and hence
unity conjugates, and monochrome. If you use them for much higher
magnification they will be nothing
like flat field, and will be beset with just about every aberration in
the book. Even worse if you use
them for colour.

Craig

--
Dave
Manuals@...
www.ArtekManuals.com