Date   

Re: My tek 2465 smokes

cmjones01
 

On 15 Dec 2017 7:52 a.m., "'hardy hansen' hardyhansen@mail.tele.dk
[TekScopes]" <TekScopes@yahoogroups.com> wrote

After not having used my tek 2465 for a while-now it really smokes-do
vagely recall it have been seen before??

The smoke is probably from the mains input filter capacitors which, after a
few decades, crack and admit moisture, then fail with a cloud of smoke. The
proper fix is to replace the capacitors. The fix I use is just to wait for
the smoke to stop (it does, eventually) and carry on using the scope.

The operation of the instrument is not affected by these capacitors, but
there's a chance it won't meet its conducted radio interference spec if
they've failed. You are free to decide whether this is something you care
about.

Chris


Re: My tek 2465 smokes

Ed Breya
 

You said it smokes, but does it run? Open it up and look for the source. Could be one of the infamous bad X-caps, or something else burning up and ready to crap out entirely. It's best to look while there's still some smoke left.

Ed


My tek 2465 smokes

hardyhansendk
 

Hello

After not having used my tek 2465 for a while-now it really smokes-do vagely recall it have been seen before??

Any advise welcome as i am not in a position right now to dig very deep because of health issues.

Thanks

Hardy.





Fra: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com]
Sendt: 14. december 2017 17:58
Til: TekScopes@yahoogroups.com
Emne: Re: [TekScopes] My 2462A died suddenly





El 14/12/2017 a las 10:47 a.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

Sorry, my reply will be slow and limited while on holiday. Your
symptoms seem like a bad capacitor. There is a fault in the service
manual that interchanges C1115 and C1132. This causes you to fit a 35
volt capacitor (c115) in a 87 volt circuit (where C1132 should be).
So trust the schematic and your ohm meter, buzz out the circuit and
make certain that your caps are fitted to the schematic. Ignore the
board outline drawings.

Sent from Yahoo Mail for iPhone

On Tuesday, December 12, 2017, 4:35 AM, Joachim Lange ti8jlh@gmail.com
[TekScopes] <TekScopes@yahoogroups.com> wrote:


El 10/12/2017 a las 11:54 p.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

Glad to hear it is fixed. Thanks for reporting back. I was worried
because I am leaving for a winter holiday and was not going to be much
help until 2018. Best wishes for the Holidays.
Mac

On ‎Saturday‎, ‎December‎ ‎9‎, ‎2017‎ ‎09‎:‎09‎:‎38‎ ‎PM‎ ‎CST,
Joachim Lange ti8jlh@gmail.com [TekScopes] <TekScopes@yahoogroups.com>
wrote:


El 08/12/2017 a las 01:30 a.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

Change C1066. Then verify that you have the dummy load connected
properly and check the voltage on the collector of Q1062. If the
voltage on the collector of Q1062 is wrong after that, double check
the voltages on Q1050. Here is how everything is supposed to work:
Q1050 creates pulses that energize T1050. One of the windings of
T1050 drive a full wave rectifier CR1062 through CR1065. The
rectified pulses are filtered by C1066 to provide the 12.5 volts on
the collector of Q1062. Its pretty hard for other parts, like Q1066,
to drag down that voltage. I think Q1062 would get really hot if that
were happening. My opinion, is that either T1050 is not being properly
energized or there is a fault in the rectifiers CR1062 through CR1065,
or the filter capacitor C1066 is not storing enough energy. C1066 is
the most likely fault and its easy to change.

On ‎Thursday‎, ‎December‎ ‎7‎, ‎2017‎ ‎08‎:‎49‎:‎57‎ ‎PM‎ ‎CST,
Joachim Lange ti8jlh@gmail.com [TekScopes] <TekScopes@yahoogroups.com>
wrote:


El 04/12/2017 a las 12:18 a.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

Its a problem that the voltage on the emitter of Q1062 is less
than 11
Volts. Check the voltage on the collector of Q1062, it should be at
least 12.5 Volts. If it is not, check C1066 (or replace it). Until
you get the voltage at the collector of Q1062 and emitter of Q1062
right the gate drives of Q1060 and Q1070 will have errors that can
keep the rest from working.

On ‎Sunday‎, ‎December‎ ‎3‎, ‎2017‎ ‎08‎:‎30‎:‎33‎ ‎PM‎ ‎CST,
Joachim
Lange ti8jlh@gmail.com [TekScopes] <TekScopes@yahoogroups..com>
wrote:


El 17/11/2017 a las 01:18 a.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

Much of the 2465B is the same as the 2465A. The power supplies are
identical. But a service manual for the 2565A will eventually be
necessary (calibration, etc.). I got the manual for my 2465A from
Artek manuals. They are excellent scans of original manuals. The
owner is a member of this group.
On Thursday, November 16, 2017, 8:27:10 PM CST, Joachim Lange
ti8jlh@gmail.com [TekScopes] <TekScopes@yahoogroups.com> wrote:


El 16/11/2017 a las 06:28 p.m., machine guy machineguy59@yahoo.com
[TekScopes] escribió:

First, I assume you are aware that the power supply will not
operate
properly without a load and may in fact be damaged if operated
without
a load. After that, I am very doubtful that the problem is
caused by
U1030 (a TL494). The operation of U1030 depends on voltage
from the
collector of Q1021 and you measured that to be zero. I am not
concerned that you have a TL594 instead of a TL494, I think
TL594 is a
suitable substitute for a TL494. So I suggest you not change
TL494
without more information.
Second, I assume you are aware that measurements in this
area are
directly connected to mains power and can be dangerous. It is
advisable that you use an isolation transformer to remove the
scope
from direct mains connections when working in this area. After
that,
the zero voltage on Q1021 collector is a key indicator that the
PSU is
not starting at all. You may want to refer to the service manual
theory of operation for the PSU and the key role that Q1021
plays in
start up and static operation. Specifically, the conduction of
Q1021
depends on base current drive from Q1022 and Q1022 can be shut
down by
over-current sensed by Q1040. More measurement in this area
may give
a clue to why there is no voltage on the collector of Q1021. I
suspect the collector voltage on Q1040 will be low (say less
than 6
volts).
Did you check the resistance of R1020 and the leakage of C1025?

On Thursday, November 16, 2017, 4:58:03 PM CST, Joachim Lange
ti8jlh@gmail.com [TekScopes] <TekScopes@yahoogroups.com> wrote:


Hello everybody,
I hope you can help me repairing the PSU of my 2465A.
I took out the power supply and connected it to power. The fuses
all are
ok. I coud see that there is a voltage at the emitter of
Q1021. Not
exactly 13.2V but one more Volt. At the colector of the same
Q1021
there
is 0V.
I revised all the resistors and also Q1021, Q1022, Q1030,
Q1040 and
Q1050. Also all the CR's (diodes).All these components are good.
I did not pull out U1030 because I am a little unsecure
doing that
and I
don't have a TL494. The scope has a TL594 instead. Are they the
same?
I will look at the computer PS I have laying around because I
think
these ICs are installed in some of those.
But please could anybody tell me if this could be the failure?
I have some other questions about the caps in this PSU but I
will make
them later.
Thank you very much for your advises.

Joachim TI8JLH

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

Thank you for your fast answer.
Yes the resistance R1020 is ok and C1025 looks healty.
Tomorrow I will assemble the two parts and look for the voltage
on the
collector of Q1021.
I was searching for the theory of operation on the web because my
manual
don¨t have it. I found one for 2465B.
The low power supplies are the same for both models.
I will write tomorrow with more.
Thank you

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

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

Hello,
Thank you for your help.
I am still trying to repair the PSU.
I replaced 11 resistors. Most of them were open and the others
doubled
their value. Also three caps looked as they were leaking. I replaced
them too. (the ESR was ok)
I reasembled the PSU and at first I was very happy, but after one
minute
the screen began to flicker and than it turned off.
I took it off again and build the Primary Test Load and also I
used my
power supply. Not together.
With the Test Load connected there is 120V across load but the gate
drives of Q1060 and Q1070 is only 4.6V instead of 11V.
The volts supplied from emitter of Q1062 is about 9V.
The U1030 is working. The gate drive of Q1050 is ok.
Do you think that the regulator board is the problem or could it be
U1066?
Thank's
Joachim





Hello
Now I got again 120V at the test load. I removed U1066 and used a
socket
to install it.
With the U1066 in place I have the same voltages as before.
With the removed U1066 there as about 10V at the gates and 10V on the
emitter of Q1062.
I wanted to know what is bringing down the voltages on the emitter and
collector of Q1062.
Without U1066 the voltages still dont match.
May be it is the Q1062.
Do you have an idea how to check for the missig voltages?
Thank you.

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

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

Hello ,
I am very sorry to tell you about the mistake I made and that made me
waste my time and a lot of energy.
I forgot to bridge J207 and J206.
After I did that, voltages are ok now.
Thanks for your time and for your explanation of the circuit.
I'm very sorry for wasting your time and of the others who helped.
Regards
Joachim

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



Hello Mac,
When I turned the scope on it worked for half hour and than it started
blinking. All leds where blinking and on the screen there was a big dot
tha disappeared and came back and so on.
I took the PSU apart again and connected the load I built.
The voltages on emitter of Q1062 is over 11V and the collector has about
19V.
BUT the gate drives of Q1060 and Q1070 are only 5.6V and not 11V.
Must I replace U1062, U1064 and U1066?
What do you think?
Sorry for bother you again on your holydays.
Joachim



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Hi,
I replaced U1062 and U1064 because there were laying around. but I don't
have U1066.
Now what I can see is that there is 11V on one gate of the Q1060 or
Q1070 and on the other there are only 5V.
Looks that U1066 is bad?
Capacitors are ok.
Thank you for responding on your holydays.
Joachim








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


Re: Deane Kidd and the Metric System

stefan_trethan
 

Thanks, Ian, for that neat trick with the 256 method. I'll use it for sure.

And thank you Tom, for pulling our leg. ;-)

ST

On Fri, Dec 15, 2017 at 1:36 AM, Tom Jobe tomjobe@gmail.com
[TekScopes] <TekScopes@yahoogroups.com> wrote:
That is a very neat trick... but consider this simple plan:
For the fractional part of the dimension, divide the bottom number into
the top number to get its decimal equivalent.
Example (7/16" = 7 divided by 16 gives you 0.4375 inches)
If there are whole inches involved in the measurement then it becomes
1.4375, 2.4375 etc.
Divide the decimal inch number by .03937 and you have your millimeter
equivalent.
Example ( our 7/16" is 0.4375 decimal inches, we divide it by .03937 and
we have our answer of 11.11125 mm.
Memorizing the number .03937 solves the whole problem going either way,
to or from inches and millimeters.
Let's have an example of going from millimeters to inches:
If you multiply 100mm by .03937 you will get it's equivalent in inches,
100 x .03937 = 3.937 inches.
The number .03937 is simply how many inches are in one millimeter.
This .03937 method was the common way that millimeters and inches were
dealt with in shops I worked at in the US.
tom jobe...


Re: c-12 camera

Glydeck
 

I love this!

Sent from my iPad

On Dec 14, 2017, at 8:04 AM, 'Craig Sawyers' c.sawyers@tech-enterprise.com [TekScopes] <TekScopes@yahoogroups.com> wrote:

That is really neat!

Craig

See my flower pot adapter for a 7623A:

https://eb4apl.ure.es/camerascope/camscope_en.htm

Regards,

Ignacio, EB4APL

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


Replacement caps for 465B

n4buq
 

Anyone have a good list / supplier for the electrolytic caps in the LVPS of a 465B? I had some of the adapter discs made (the kind that take a snap-in cap) so looking for that form factor.

Here's the specs from the manual:

C4419 5000uF 25V +100% / -0%
C4429 1200uF 100V +75% / -10%
C4439 550uF 100V +75% / -10%
C4521 5500uF 30V +100% / -10%
C4531 5000uF 25V +100% / -10%

Was considering the same 6800uF, 35V, 20% cap (Mouser P/N 647-LGU1V682MELZ) for C4419, C4521, and C4531. Given they're originally +100% caps, I presume that'd be okay? Anyone have better choices?

Thanks,
Barry - N4BUQ


Re: Deane Kidd and the Metric System

n4buq
 

I worked in a metric shop for 10 years. I pretty much always used 25.4 as the conversion factor. 0.03937 is a rounded recriprocal of 25.4 which is technically the correct conversion factor between inches and millimeters (and easier for me to remember).

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "Tom Jobe tomjobe@gmail.com [TekScopes]" <TekScopes@yahoogroups.com>
To: TekScopes@yahoogroups.com
Sent: Thursday, December 14, 2017 6:36:53 PM
Subject: Re: [TekScopes] Deane Kidd and the Metric System

That is a very neat trick... but consider this simple plan:
For the fractional part of the dimension, divide the bottom number into
the top number to get its decimal equivalent.
Example   (7/16" = 7 divided by 16 gives you 0.4375 inches)
If there are whole inches involved in the measurement then it becomes
1.4375, 2.4375 etc.
Divide the decimal inch number by .03937 and you have your millimeter
equivalent.
Example ( our 7/16" is 0.4375 decimal inches, we divide it by .03937 and
we have our answer of 11.11125 mm.
Memorizing the number .03937 solves the whole problem going either way,
to or from inches and millimeters.
Let's have an example of going from millimeters to inches:
If you multiply 100mm by .03937 you will get it's equivalent in inches,
100 x .03937 = 3.937 inches.
The number .03937 is simply how many inches are in one millimeter.
This .03937 method was the common way that millimeters and inches were
dealt with in shops I worked at in the US.
tom jobe...


On 12/14/2017 4:02 PM, 'Craig Sawyers' c.sawyers@tech-enterprise.com
[TekScopes] wrote:

On the topic of conversion between Imperial and SI units of length
there is a well known method of
quickly converting aliquot parts of an inch to millimetres using the
approximation 254 = 256

If you have a fractional inch dimension, multiply top and bottom of
the fraction by two repeatedly
until
the denominator equals 256.? Shift the decimal point of top and
bottom one place to the left.? The
numerator now equals the inch dimension times 25.6, which is the
equivalent number of millimetres
(to less than 1% error)
Ian
Darn, that is a neat trick. I really like simple numerical methods
like that.

Craig



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



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Yahoo Groups Links




Re: Tek 2753P Manuals

tomb8mail
 

So, I found some manuals for a 494AP which is similar to mine. Also found some 494 repair notes which looks to be a good find. Anyway, I finally got around to powering it up with a dim bulb circuit and a 200W bulb. A couple LEDS on the front came on and the scope backlights but that is it. The bulb in the test circuit also lit to about half brightness I would guess, not sure if it's safe to hook up to the variac and get some power board voltages??? Got the case off, very nice and clean inside, good sign. One of the main filter caps has the plastic a little ruffled on top so maybe that got a little hot at some point. Having a little difficulty getting to the power board, not sure if the go by from the 494 is the same so I am kinda hesitant to go any further trying to disassemble it. Hoping it's just a few electrolytics to replace get her up and going. The downside to this unit is that it is a huge beast of a machine. Have no clue where I will set this up if I ever get it going.

http://www.antiqueradios.com/forums/download/file.php?id=198994


Re: 7904A readout bounce

 

Thermal offsets are literally that, offset voltage drift in the
differential pairs through the horizontal and vertical signal paths.
They are caused by the changes in operating points with signal level
which result in a change in power dissipation and temperature in the
individual transistors.

At higher frequencies, the changes in power dissipation average out
but alternate mode occurs at a frequency determined by the sweep
lengths so it is slower than any individual sweep and slower yet than
the vertical signal.

If you want to see the effect in a controlled way, watch how the
readout shifts when X-Y mode is used and the beam is moved to
different points on the display. This is (usually) not the result of
electrical leakage between the beam position and readout; it is caused
by changing the operating point of the transistors ultimately changing
their temperature which changes their current gain and base-emitter
voltage.

On Thu, 14 Dec 2017 21:56:26 +0000, you wrote:

On further investigation this is vertical bounce due to ALT mode being invoked either on the plug-in or the mainframe when lowish scan rates are used. I didn't see anything about this matter in the manual; I wonder if there is a supply decoupling problem somewhere?

Regards

Nigel


Re: Deane Kidd and the Metric System

Tom Jobe <tomjobe@...>
 

That is a very neat trick... but consider this simple plan:
For the fractional part of the dimension, divide the bottom number into
the top number to get its decimal equivalent.
Example (7/16" = 7 divided by 16 gives you 0.4375 inches)
If there are whole inches involved in the measurement then it becomes
1.4375, 2.4375 etc.
Divide the decimal inch number by .03937 and you have your millimeter
equivalent.
Example ( our 7/16" is 0.4375 decimal inches, we divide it by .03937 and
we have our answer of 11.11125 mm.
Memorizing the number .03937 solves the whole problem going either way,
to or from inches and millimeters.
Let's have an example of going from millimeters to inches:
If you multiply 100mm by .03937 you will get it's equivalent in inches,
100 x .03937 = 3.937 inches.
The number .03937 is simply how many inches are in one millimeter.
This .03937 method was the common way that millimeters and inches were
dealt with in shops I worked at in the US.
tom jobe...


On 12/14/2017 4:02 PM, 'Craig Sawyers' c.sawyers@tech-enterprise.com
[TekScopes] wrote:

On the topic of conversion between Imperial and SI units of length
there is a well known method of
quickly converting aliquot parts of an inch to millimetres using the
approximation 254 = 256

If you have a fractional inch dimension, multiply top and bottom of
the fraction by two repeatedly
until
the denominator equals 256.? Shift the decimal point of top and
bottom one place to the left.? The
numerator now equals the inch dimension times 25.6, which is the
equivalent number of millimetres
(to less than 1% error)
Ian
Darn, that is a neat trick. I really like simple numerical methods
like that.

Craig



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


Re: Deane Kidd and the Metric System

Craig Sawyers <c.sawyers@...>
 

On the topic of conversion between Imperial and SI units of length there is a well known method of
quickly converting aliquot parts of an inch to millimetres using the approximation 254 = 256

If you have a fractional inch dimension, multiply top and bottom of the fraction by two repeatedly
until
the denominator equals 256.? Shift the decimal point of top and bottom one place to the left.? The
numerator now equals the inch dimension times 25.6, which is the equivalent number of millimetres
(to less than 1% error)
Ian
Darn, that is a neat trick. I really like simple numerical methods like that.

Craig


Re: 7854 vs 7D20

redarlington
 

Hah, love it. You got me thinking that because of the speed, I could just
do a READX over gpib and pull the data in, process, and SENDX it back out
for display. Or, you know, display on the PC or use the specan 3 feet
away... Either way, this is very cool and much appreciated work. It also
might be neat to add a Raspberry Pi or some similar single board computer
externally to the 7854 to handle doing this without much additional bulk.
Hit a button and get the FFT.

-Bob

On Thu, Dec 14, 2017 at 1:12 AM, tekscopesinput@holgerluebben.de
[TekScopes] <TekScopes@yahoogroups.com> wrote:



Hi Dan!

Yes, the FFT program is available. You'll find a link to a zip archive at
the end of this message.
But the program needs some explanation.

The project was only a proof of concept and the program is a very limited
prototype.
<snip>


Re: Deane Kidd and the Metric System

Richard Knoppow
 

Sounds like an application for a Curta calculator.

On 12/14/2017 2:57 PM, Ian Newman ian_new@yahoo.com [TekScopes] wrote:

Hi,
On the topic of conversion between Imperial and SI units of length
there is a well known method of quickly converting aliquot parts of an
inch to millimetres using the approximation 254 = 256

I
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL



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


Re: Deane Kidd and the Metric System

Ian Newman <ian_new@...>
 

Hi,
On the topic of conversion between Imperial and SI units of length there is a well known method of quickly converting aliquot parts of an inch to millimetres using the approximation 254 = 256

If you have a fractional inch dimension, multiply top and bottom of the fraction by two repeatedly until the denominator equals 256.  Shift the decimal point of top and bottom one place to the left.  The numerator now equals the inch dimension times 25.6, which is the equivalent number of millimetres (to less than 1% error)

For example, take a fractional inch dimension - 3/8

3/8 = 6/16
3/8 = 12/32
3/8 = 24/64
3/8 = 48/128
3/8 = 96/256

3/8 inch = 9.6mm (to better than 1%)
Actual conversion = 9.525mm

In actual use, simply count how many times you need to multiply the denominator to get 256, then multiply the numerator by two that many times and write down the answer, slipping in the decimal point as you do so.

E.g. 9/16
Multiply the denominator by 2 four times (32, 64, 128, 256).  Now multiply the numerator by 2 four times - 18, 36, 72, 144 - giving 14.4mm (actual value 14.29 to four sig. fig.)

If you have whole numbers of inches, convert to irrational fractions first:
2 3/4 inch = ((2 x 4) +3)/4 inch
=11/4 inch
= 704/256
= 70.4mm (actual value 69.85)


You can improve the accuracy (using mental arithmetic) by reducing the value of the answer by 1%. Take the first significant digit of the result, move the point two places left (divide by 100) and subtract from the original result.

Doing this to the examples above gives:

3/8 inch = 9.6mm
Better approximation:
3/8 = 9.6 - 0.09
= 9.51mm
Actual value = 9.525mm

9/16 inch = 14.4mm
Better approximation:
9/16 = 14.4 - 0.1
= 14.3mm
Actual value = 14.29mm

2 3/4 inch = 70.4mm
Better approximation:
2 3/4 = 70.4 - 0.7
= 69.7mm
Actual value = 69.85mm

Even I can multiply by two in my head......

All the best,
Ian




From: "Barry n4buq@knology.net [TekScopes]" <TekScopes@yahoogroups.com>
To: TekScopes@yahoogroups.com
Sent: Thursday, 14 December 2017, 13:47
Subject: Re: [TekScopes] Deane Kidd and the Metric System

  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
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Re: 7904A readout bounce

NigelP
 

On further investigation this is vertical bounce due to ALT mode being invoked either on the plug-in or the mainframe when lowish scan rates are used. I didn't see anything about this matter in the manual; I wonder if there is a supply decoupling problem somewhere?

Regards

Nigel


Re: Deane Kidd and the Metric System

Harvey White
 

On Thu, 14 Dec 2017 17:24:26 +0000 (UTC), you wrote:

The Spanish dubloon, IIRC, had score marks on it which allowed it to
be easily broken into eighths. These were known as bits.

That we still retain the language of....

Harvey


"Life is a carnival, believe it or not.� �Life is a carnival, two bits a shot..."
� � � � � � � � �(The Band, "Life is a Carnival" - arguably the greatest example of Americana Folk Rock, ignoring the fact that most of them were Canadian)
� Dan

On Wednesday, December 13, 2017, 9:04:21 AM EST, Barry n4buq@knology.net [TekScopes] <TekScopes@yahoogroups.com> wrote:

�
The U.S. used to have a 1/8 dollar designation as a "bit". Two bits equals a quarter and is still sometimes heard amongst the older folks.

Thanks,
Barry - N4BUQ





Re: Deane Kidd and the Metric System

Geoffrey Thomas
 

On 14/12/2017 18:09, Tom Gardner tggzzz@gmail.com [TekScopes] wrote:
Inflation is a symptom; I'm more worried about the causes.
Austin Mitchell made sage observations in The Guardian on the 11th.
Even that prominent Brexiteer, John Redwood MP, advises his clients
to get their money out of the UK.
But that's too close to politics for comfort, in this group.
You're talking about THE John Redwood, arch ventriloquist and darling of linguists everywhere...

https://www.youtube.com/watch?v=GzBq0n8dxFQ

Geoff.


Re: Was: Deane Kidd and the Metric System, now nothing to do with it

Craig Sawyers <c.sawyers@...>
 

Please change the topic, fellas!

Craig

-----Original Message-----
From: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com]
Sent: 14 December 2017 19:11
To: TekScopes@yahoogroups.com
Subject: Re: [TekScopes] Deane Kidd and the Metric System

Ooh, did they upgrade the trolleys with the new pound ?

Sent from my iPhone

On 14 Dec 2017, at 17:48, Tom Gardner tggzzz@gmail.com [TekScopes]
<TekScopes@yahoogroups.com> wrote:

Too big; wouldn't fit except with extreme force :)

On 14/12/17 17:44, 'James R. Bartlett' james.r.bart@gmail.com [TekScopes] wrote:

Probably used to release the trollies.!!!!

Jim

On 14 December 2017 at 17:30, Tom Gardner tggzzz@gmail.com [TekScopes] <
TekScopes@yahoogroups.com> wrote:

On 14/12/17 16:45, John Griessen john@ecosensory.com [TekScopes] wrote:
On 12/14/2017 03:38 AM, Tom Gardner tggzzz@gmail.com [TekScopes] wrote:
The UK still mints several unusual coins which - importantly - can
be used in supermarkets.
You mean the current exchange rate on them is honored by supermarkets?
They are coins of the realm, so face value should be honoured
(presuming they are recognised)!

For obvious reasons, I would be delighted if someone offered
one to me on that basis :)





------------------------------------
Posted by: Robin Birch <robinb@ruffnready.co.uk>
------------------------------------


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

Yahoo Groups Links



Re: Tektronix 2213a manual with single page schematic diagrams

 

On Thu, 14 Dec 2017 13:33:18 -0600, you wrote:

The manual for the 2215A can be used for everything on the 2213A
except timebase B circuits.

I do not have the 2213A schematic however I uploaded some cleaned up
2215A schematics that I compiled. Thank Yahoo if their provided URL
does not work. If that is a problem, then I can upload them somewhere
else.

<https://xa.yimg.com/df/TekScopes/2215A+Schematics+11x17.pdf?token=Zq_g8pQx4iGV-mPmA7ZxVEruqanDEixxmVhl4UPcIHyKA6fBt49_tgpB1l8N5PzpTWVbv7uZ_UOczZxC0tOBizPsrChhOK3THs9jQQ9ZUJ8jtEpVmZ9iijLY52TP&type=download>
Now hosted at Tekwiki as well thanks to Kurt.

<http://w140.com/tekwiki/images/c/c4/Tek_2215A_Schematics_11x17.pdf>


Re: Deane Kidd and the Metric System

Tam Hanna
 

With all military respect, but this is bullshit.


Inflation is a symptom; I'm more worried about the causes.

Inflation is not a symptom. Inflation is a byproduct of a fiat currency and a political system. If money can be debased, it will be debased to fund "gibs me dat" programs.


--

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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