Date   
Re: 453 calibrator

Chuck Harris
 

People misinterpret things all of the time.

And people use their test equipment wrongly quite a lot.
I am not saying that is happening here, but it feels like
it might be.

If BA is truly at ground, then his scope is wired incorrectly.

Maybe someone measured BA to ground, found it wasn't, then
misinterpreting the schematic, added a jumper between BA and BB.

Maybe the coax has been subject to the soldering iron too many
times, and the center insulation is now shorted to the ground
braid.

The only reason BB is at ground is to ground the shield on the
coax. Purely a noise reduction issue.

-Chuck Harris

Mike Merigliano wrote:

Why would either BA or BB be a dead short (at ground) to Q1274's emitter? There is a
2.19K resister between the emitter and either BB or BA. I guess what I'm missing is
how someone could see a short on the schematic, even if they mis-interpreted the line
representing the board's boundary as a wire or trace. I am not an expert, so when
someone sees something on a schematic that I don't, I want to know why.

Connection BB is probably not needed when everything else is connected anyway, as
there are two other ground returns -- the one for the 1 volt BNC output looks
redundant to BB, and another 180 ohms kicks-in for 0.1 output. The other involves the
current-test loop, and there is another 220 ohms involved.

Re: 453 calibrator

Mike Merigliano
 

Why would either BA or BB be a dead short (at ground) to Q1274's emitter? There is a 2.19K resister between the emitter and either BB or BA.  I guess what I'm missing is how someone could see a short on the schematic, even if they mis-interpreted the line representing the board's boundary as a wire or trace. I am not an expert, so when someone sees something on a schematic that I don't, I want to know why.

Connection BB is probably not needed when everything else is connected anyway, as there are two other ground returns -- the one for the 1 volt BNC output looks redundant to BB, and another 180 ohms kicks-in for 0.1 output. The other involves the current-test loop, and there is another 220 ohms involved.

On 5/9/2018 12:29 PM, Chuck Harris wrote:
No, you aren't missing anything. What Jeff was saying
is if BA is truly at ground, then you cannot have a signal
out your calibrator. It may appear to be grounded if you
use an ohmmeter that is on too high a scale... due to the
160, or so ohms that the circuit inherently has to ground.

-Chuck Harris

Mike Merigliano wrote:
The signal is not shorted to ground -- it goes through a 2.19K resistor in series
first, so there is no short. My Tek 453 has a calibrator signal, at specification. My
ohmeter and voltmeter check measurements between/around Q1274, point BA, R1274, and
point BB match what is on the schematic.

Maybe I am missing something.

Re: 7T11 sampling timebase - how does it behave?

Roger Evans
 

Chris, Dennis,
I wondered why the 7S14 had the delayed timebase and Vernier control of the delta-delay markers but this was omitted on the 7T11. There could be several possible reasons and Dennis may be able to point to the truth.

The 7S14 has a delay line so that you can see the trigger point and make accurate time measurements from the trigger to other features on the waveform. On the 7T11 in sequential scan you are looking 10s of nsec after the trigger so you largely lose any time reference from the trigger event.

Another very good reason might be that the 7T11 is already very well filled with multiple boards.

Roger

Re: 453 calibrator

Brendan
 

BTW if anyone needs the 453 above SN 20,000 manual I can send it to you. I can't remember where I got it. It was a 6 part .rar download.

Re: 453 calibrator

Chuck Harris
 

No, you aren't missing anything. What Jeff was saying
is if BA is truly at ground, then you cannot have a signal
out your calibrator. It may appear to be grounded if you
use an ohmmeter that is on too high a scale... due to the
160, or so ohms that the circuit inherently has to ground.

-Chuck Harris

Mike Merigliano wrote:

The signal is not shorted to ground -- it goes through a 2.19K resistor in series
first, so there is no short. My Tek 453 has a calibrator signal, at specification. My
ohmeter and voltmeter check measurements between/around Q1274, point BA, R1274, and
point BB match what is on the schematic.

Maybe I am missing something.

On 5/9/2018 10:19 AM, Jeff Urban wrote:
On Wed, May 9, 2018 at 08:13 am, Mike Merigliano wrote:

There is no error here; BB is a ground point, and the emitter of Q1274 goes to
it via R1274 in series.
Then there can be no output at the calibrator terminal unless the whole thing
floats and has a separately isolated power supply. The signal would forever be
shorted to ground.

Re: 453 calibrator

Mike Merigliano
 

The signal is not shorted to ground -- it goes through a 2.19K resistor in series first, so there is no short. My Tek 453 has a calibrator signal, at specification. My ohmeter and voltmeter check measurements between/around Q1274, point BA, R1274, and point BB  match what is on the schematic.

Maybe I am missing something.

On 5/9/2018 10:19 AM, Jeff Urban wrote:
On Wed, May 9, 2018 at 08:13 am, Mike Merigliano wrote:

There is no error here; BB is a ground point, and the emitter of Q1274 goes to
it via R1274 in series.
Then there can be no output at the calibrator terminal unless the whole thing floats and has a separately isolated power supply. The signal would forever be shorted to ground.



Re: Way OT, but maybe interesting: Li-ion battery observations and questions

stefan_trethan
 

They make plenty of mistakes too.
Maybe worst was the DHR243 hammer (XRH01 in the US).
I could tell something wasn't right just by turning the chuck by hand,
it sounded awful as if something was binding. After some tinkering I
noticed the problem went away if I loosened the gearbox screws ever so
slightly. Power draw from the battery with the drill turning idle also
dropped to about half. They just mashed the gears together way too
tight, causing the binding. Some shims fixed that but this it not OK
for a premium product, clearly a design error not accounting for the
length tolerance of an injection molded plastic housing.

The grips are way too skinny even for small hands and the rubber
overmolding is very rough. On some of the tools there is sharp
injection molding flash right underneath the trigger button, where you
feel it every time you pick the thing up. Generally the fit of the
housings is poor, the Bosch tools fit together so well you barely
notice any seam but the Makita tools all have huge gap designed in so
the mismatch isn't so obvious. The Bosch tools feel nice and smooth in
the hand, you want to hold them. Not so with Makita, you almost want
to wear gloves so the rubber off-road-tire tread doesn't hurt your
hand.

There are too many safety catches on some of the tools. I only have
two hands and accordingly reduced the number of safety catches to
match the number of hands. I consider it sufficient if both hands are
required to activate a tool, I don't need a safety button for each
foot and the tongue too.

Don't get me wrong, I know this is criticism at a somewhat elevated
level. But these are expensive premium tools and I had to take most of
them apart immediately to fix them in some way (including the
chainsaw).

If it wasn't for the one thing - the battery platform, I would have
sent the first items back and switched to Bosch while I still could
(no hope now). Bosch just pissed me off with making the batteries for
their power tool and garden tool range intentionally incompatible,
just to spite me.

ST

On Wed, May 9, 2018 at 6:11 PM, Pete Lancashire <xyzzypdx@...> wrote:
I know this thread is getting pretty long here but I'll also toss in my
vote for Makita. They're one of the few independent companies that still
make design and manufacture their own tools and the one time I had problems
with a model that had a brushless motor Makita of America sent me a
replacement with an RMA tag and told me to return the defective one one at
my leisure.

Re: 453 calibrator

 

On Wed, May 9, 2018 at 08:13 am, Mike Merigliano wrote:


There is no error here; BB is a ground point, and the emitter of Q1274 goes to
it via R1274 in series.
Then there can be no output at the calibrator terminal unless the whole thing floats and has a separately isolated power supply. The signal would forever be shorted to ground.

Re: Way OT, but maybe interesting: Li-ion battery observations and questions

Pete Lancashire
 

I know this thread is getting pretty long here but I'll also toss in my
vote for Makita. They're one of the few independent companies that still
make design and manufacture their own tools and the one time I had problems
with a model that had a brushless motor Makita of America sent me a
replacement with an RMA tag and told me to return the defective one one at
my leisure.

On Mon, May 7, 2018, 12:19 PM stefan_trethan <stefan_trethan@...> wrote:

I just bought a Makita DUC353 (XCU03 in the US) and I'm also happy with it.
Compared to other battery saws it uses a different concept, it runs at
high chain speed (similar to a gas powered saw) but has less torque.
With the narrow chain this works out fine as long as it is sharp, but
you can bog it down if you push hard.

It uses two 18V batteries, I use 5Ah ones (different ones are
available), so 180Wh which makes it 10 minutes runtime at 1kW (full
power). This seems short, but you don't always use full power and my
Stihl saws will do maybe 15-20 minutes a tank at full throttle so not
such a big difference.

Don't get me wrong, the Stihl saws work great. They start easily and
plenty of power, no issues at all. But for a few small cuts it is a
hassle to get one ready, get your hearing protection, it's still
noisy, smelly, and I really don't like loud motor noises and the smell
of petrol (other men may differ).

I wouldn't expect to use only the battery saw for a large tree, but
for small stuff, especially intermittent work, it is ideal because you
don't have to pull the cord all the time, you just push the buttons
and it cuts. Also if you have to climb something it's an advantage for
sure. I think it is somewhat more dangerous than a gas saw because it
is so easy to use, but I bet it'll cut you just as bad, so don't get
careless.

I already have _a lot_ of Makita 18V tools so I didn't have to buy the
batteries or charger.
Bosch is better quality in the 3 cell (12V) range, but the Makita
concept using one or two 18V batteries is superior for high powered
tools. 500W with one battery and 1kW with two, you can do some real
work with that.

I would say that brushless motors made a similar difference as lithium
batteries over Nickel.
Combine the two and you don't really need a cord for most things.

I really want to make a battery powered soldering iron with a JBC
handle and a 18V Makita battery, anyone up for a challenge?

ST

On Mon, May 7, 2018 at 8:18 PM, Ed Breya via Groups.Io
<edbreya=yahoo.com@groups.io> wrote:
I've been up at the farm this weekend, and decided to take down a
medium-sized, ratty old dying tree in the vineyard. Last year I took a
chance and bought one of these 40V Li-ion battery powered small (14")
chainsaws to try out on small, sporadic trim work. I've used successfully
it a few times on fallen branches and small stuff, but was dubious about it
holding up on "real" work.

I've had many gas saws and weeders etc over the years, and invariably
they are out of commission after a couple of seasons and over-wintering
storage, so need to be cleaned up and worked over or fixed to get going
again. The thing I've noticed recently is that the rubbery material primer
pump bulbs deteriorate rapidly and crack, so you can't prime the carburetor
to get started after storage. It seems that a lot of plastic and rubber
materials nowadays that should be permanent, are almost biodegradable and
crap out way too soon.

Of course, my last previously working gas saw has its primer bulb shot,
so it was time to try the new battery one, and give it a real workout. I
don't know what kind of tree this is - it's more like a giant bush, with a
number of large trunks ranging from maybe 4-10" diameter at the base,
reaching about 25' high. The wood is fairly hard and dense, so the fatter
sections had to be chunked out from firewood-sized to a few feet long for
lifting. The branches are gnarly and viney, and all intertwined, including
deadwood and fresh shoots, so it took a lot of cuts just to separate and
trim down to manageable pieces for moving and piling up.

Sorry for the highly detailed description, but I just wanted to
emphasize that although this was nowhere near the largest tree I've fallen,
it was perhaps the most tedious for its size, in terms of getting it down
on the ground and manageable for moving out the debris. Anyway, the saw
worked great! I had to do perhaps 100 large cuts of 2" and up, and 200
small ones, over about an hour and a half. It runs much slower, but
"torquier" than a gas saw, so cuts slower, but just keeps on going and
going. I figured I would quit when the battery ran out, but I ran out
first. I got it all down and now have a huge pile of debris. The saw
apparently still had plenty of juice!

Now for the technical part. Many modern battery packs have a "gas gauge"
indicator built in, like a few LEDs that light up when you press a button.
When I was done with cutting, I pulled the battery, and was shocked that it
read 3 out of 4 bars, so to speak - I had only used up a small fraction of
the capacity, if this was correct. So now I'm wondering just how accurate
and/or linear this indication is. I assume that the Li-ion charge-discharge
management ICs nowadays have plenty of smarts built in, including capacity
level.

The question is, is it a measured and calculated indication of actual
remaining joulage, or just a rough estimate based on the battery
voltage/discharge curve? This pack is rated 40V, 2.5 A-h, so 100 W-h. I'm
amazed at how much work I got done with this much available juice, let
alone a fraction of it. So, does anyone know much about the character of
these battery management ICs, especially the indicator part?

In conclusion, I'm very impressed with today's Li-ion technology. I will
be getting at least one more of these saws and some spare batteries. They
will be my go-to saws from now on, although I'll still fix and keep the old
gassers for seriously bigger stuff.

Ed




Re: 453 calibrator

ArtekManuals
 

Ooooops

Well I meant to reply OFF LIST Still getting userd to Groups.IO
-DC

On 5/9/2018 11:39 AM, Artekmedia wrote:
Dale
[REPLY OFF LIST]

Unless I missed something it appears to me that the 453 manual on Bama is part # 070-0478-00 which is for serial #'s below 20000. The manual for the higher serial numbers is 070-0755-00

-DC
manuals@...

On 5/9/2018 10:07 AM, Dale H. Cook wrote:
At 09:49 AM 5/9/2018, Chuck Harris wrote:

The drawn line that connects them was originally blue, or grey, and has had its density, and color, mucked with by the scanner until it appears black, like an ordinary wire.
That is one reason why my 453 (Serial 20,000+) scan at BAMA has those prints scanned in color.

Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
http://plymouthcolony.net/starcity/radios/index.html




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

Re: How old?

ArtekManuals
 

Pete
If you had kept those tapes you would likely have a box full of brown dust today :-)
\-DC

On 5/9/2018 11:44 AM, Pete Lancashire wrote:

In fact looking back I used CS's database at times when I worked in
component engineering then I did corp's systems

Only if I had kept a few of those 9 track 1/2 inch tapes !!

-pete



On Wed, May 9, 2018 at 8:01 AM, Chuck Harris <cfharris@...> wrote:

If you search the group, there was a post by a former
tektronix line manager that explained why the numbers
cannot readily be used for estimating quantities of an
instrument made, or as indicators of age.

In brief, the number sequences made whole jumps when the
production line was restarted after a significant pause,
or a change in the design. The instruments made during
a production run, could be sold over multiple years if
they over built, or there could be multiple runs in a
year, if there was great demand.

About all that could be said is the production in a
group of instruments was monotonically increasing, and
that the production managers at one point had logs of
which groups were made on which dates, but they don't
appear to have been saved, as they weren't very important
long term.

-Chuck Harris

Brian Cockburn wrote:
Artekmedia, I'm not sure I understand what you mean by "serial numbers
have nothing to do with time". Are serial numbers not monotonically
increasing? And I've always assumed that each model has its own serial
number sequence, rather than there being one Tek-wide serial number
sequence. Does anyone know definitively one way or the other?



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

Re: How old?

ArtekManuals
 

Brian

Chuck Harris' email reply took the words right out of my mouth

Tek serial numbers  have nothing to do with an actual  manufacturing date and not always continuous over m
long periods of time.

For those of you who are just tuning in, Since Brian didn't include the prior posts and are wondering what all this is about I have included them below for calcification and continuity

_*
*__*PRIOR POSTS*_

On 5/3/2018 9:21 PM, Brian Cockburn wrote:
Given a model number and a serial number is there a way to look up or estimate the time of manufacture?

Thanks, Brian.

ArtekMedia Replied:

Brian

Not really ...Tek serial numbers have nothing to do with time

Only way that gets you close is looking at date codes on caps and IC's

-DC
manuals@...

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

Re: How old?

ArtekManuals
 

Yes increasing but not necessarily continuous and never tied to any particular date code that you can determine with your secret Tektronix Decoder Ring

-DC
manuals@...

On 5/9/2018 11:39 AM, Pete Lancashire wrote:
Are serial numbers not monotonically increasing?

yes see below

And I've always assumed that each model has its own serial number
sequence, rather than there being one Tek-wide serial number sequence.

wrong, see below.


Let me try.

Other than rare occasions Tek when the adopted the "six digit" serial
number system it went like this

The letter identified the manufacturing location. The number 0 - Zero was
also used.

the next two digits were for design changes during the manufacturing life
of the product, the digits started at 101.

the remaining four digits where starting at 0001 the build sequence number.

So far example the first 7704 of the line at Beaverton would have the
serial number B010101.

An exception is when a design change was major. There the serial numbers my
go from B041234 to B050101.

I think the 465 did this, but don't hold me to it.

In these cases a new service manual was produced.

Hence if you have in front of you two 7704's and one is B021234 and the
other is B071514, the only thing you
can say is the on with serial number B071514 was built after the other one.



Many years ago I posted the complete list of sites codes etc, but others
may have it now.

-pete



On Wed, May 9, 2018 at 7:43 AM, Brian Cockburn <
brian.cockburn.1959@...> wrote:

Artekmedia, I'm not sure I understand what you mean by "serial numbers
have nothing to do with time". Are serial numbers not monotonically
increasing? And I've always assumed that each model has its own serial
number sequence, rather than there being one Tek-wide serial number
sequence. Does anyone know definitively one way or the other?



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

Re: How old?

Pete Lancashire
 

The most complete list of instrument / serial number / dates I say when I
was at Tek was in possession of customer service.

It was updated daily and was on green-bar, later one could get the same
information on a 3270 terminal.

One use of that information was to determine if a item was still within the
warranty period

In fact looking back I used CS's database at times when I worked in
component engineering then I did corp's systems

Only if I had kept a few of those 9 track 1/2 inch tapes !!

-pete

On Wed, May 9, 2018 at 8:01 AM, Chuck Harris <cfharris@...> wrote:

If you search the group, there was a post by a former
tektronix line manager that explained why the numbers
cannot readily be used for estimating quantities of an
instrument made, or as indicators of age.

In brief, the number sequences made whole jumps when the
production line was restarted after a significant pause,
or a change in the design. The instruments made during
a production run, could be sold over multiple years if
they over built, or there could be multiple runs in a
year, if there was great demand.

About all that could be said is the production in a
group of instruments was monotonically increasing, and
that the production managers at one point had logs of
which groups were made on which dates, but they don't
appear to have been saved, as they weren't very important
long term.

-Chuck Harris

Brian Cockburn wrote:
Artekmedia, I'm not sure I understand what you mean by "serial numbers
have nothing to do with time". Are serial numbers not monotonically
increasing? And I've always assumed that each model has its own serial
number sequence, rather than there being one Tek-wide serial number
sequence. Does anyone know definitively one way or the other?





Re: Way OT, but maybe interesting: Li-ion battery observations and questions

Mike Merigliano
 

Given that ethanol has some energy content (about 67% of gasoline on a BTU basis), a 10% decrease in MPG with 10% ethanol is an unexpected effect for ethanol alone. Studies at Oak Ridge National Lab (see  NREL/TP-540-43543) report a 3.7% reduction in MPG in ordinary vehicles due to 10% ethanol in gasoline. Cold temperatures, tread differences on snow tires, and snow-covered roads could reduce MPG further.  An informal experiment is my wife's travel over many years with a diesel car. Her car averages 50 MPG in summer, and averages 47 MPG in winter, with essentially the same driving habits. So, there is 6% loss with no ethanol involved.

On 5/8/2018 8:31 PM, Chuck Harris wrote:
In my experience, when you add 10% ethanol, you
reduce the gas mileage by 10%. Effectively, it
is entirely wasted.

-Chuck Harris


Re: How old?

Richard Solomon <dickw1ksz@...>
 

Ask any Collins Collector !!

73, Dick, W1KSZ

On Wed, May 9, 2018, 7:43 AM Brian Cockburn <brian.cockburn.1959@...>
wrote:

Artekmedia, I'm not sure I understand what you mean by "serial numbers
have nothing to do with time". Are serial numbers not monotonically
increasing? And I've always assumed that each model has its own serial
number sequence, rather than there being one Tek-wide serial number
sequence. Does anyone know definitively one way or the other?



Re: How old?

Pete Lancashire
 

Are serial numbers not monotonically increasing?

yes see below

And I've always assumed that each model has its own serial number
sequence, rather than there being one Tek-wide serial number sequence.

wrong, see below.


Let me try.

Other than rare occasions Tek when the adopted the "six digit" serial
number system it went like this

The letter identified the manufacturing location. The number 0 - Zero was
also used.

the next two digits were for design changes during the manufacturing life
of the product, the digits started at 101.

the remaining four digits where starting at 0001 the build sequence number.

So far example the first 7704 of the line at Beaverton would have the
serial number B010101.

An exception is when a design change was major. There the serial numbers my
go from B041234 to B050101.

I think the 465 did this, but don't hold me to it.

In these cases a new service manual was produced.

Hence if you have in front of you two 7704's and one is B021234 and the
other is B071514, the only thing you
can say is the on with serial number B071514 was built after the other one.



Many years ago I posted the complete list of sites codes etc, but others
may have it now.

-pete



On Wed, May 9, 2018 at 7:43 AM, Brian Cockburn <
brian.cockburn.1959@...> wrote:

Artekmedia, I'm not sure I understand what you mean by "serial numbers
have nothing to do with time". Are serial numbers not monotonically
increasing? And I've always assumed that each model has its own serial
number sequence, rather than there being one Tek-wide serial number
sequence. Does anyone know definitively one way or the other?



Re: 453 calibrator

ArtekManuals
 

Dale
[REPLY OFF LIST]

Unless I missed something it appears to me that the 453 manual on Bama is part # 070-0478-00 which is for serial #'s below 20000. The manual for the higher serial numbers is 070-0755-00

-DC
manuals@...

On 5/9/2018 10:07 AM, Dale H. Cook wrote:
At 09:49 AM 5/9/2018, Chuck Harris wrote:

The drawn line that connects them was originally blue, or grey, and has had its density, and color, mucked with by the scanner until it appears black, like an ordinary wire.
That is one reason why my 453 (Serial 20,000+) scan at BAMA has those prints scanned in color.

Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
http://plymouthcolony.net/starcity/radios/index.html



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

Re: 453 calibrator

Mike Merigliano
 

To check the schematic, I opened up my 453 (>20000). There is no error here; BB is a ground point, and the emitter of Q1274 goes to it via R1274 in series. Even if the line denoting the edge of the board, labeled as "Partial A Sweep Board", and blue on original schematic (see Dale Cook's reproduction for >20000 serial number units) is mistaken for a wire/trace, the connection is the same. Why would Q1274, with about 6 volt DC emitter voltage "blow up" with a 2.19K resistor in series to ground?

On 5/8/2018 11:00 PM, Jeff Urban wrote:
There must be some sort of error concerning the connection at BB. If it is as shown there would never be any output. It is either a mistake or they found a new way to use a symbol. I have run into alot of that in consumer, so much so that I always check, never trust. I have seen a line representing a wire or trace on a PC tht says 12 volts and about an inch away says 0 volts. I have seen mistakes that would pretty much turn the unit into a bomb. (almost wonder if they'e really mistakes...)

Re: How old?

Chuck Harris
 

If you search the group, there was a post by a former
tektronix line manager that explained why the numbers
cannot readily be used for estimating quantities of an
instrument made, or as indicators of age.

In brief, the number sequences made whole jumps when the
production line was restarted after a significant pause,
or a change in the design. The instruments made during
a production run, could be sold over multiple years if
they over built, or there could be multiple runs in a
year, if there was great demand.

About all that could be said is the production in a
group of instruments was monotonically increasing, and
that the production managers at one point had logs of
which groups were made on which dates, but they don't
appear to have been saved, as they weren't very important
long term.

-Chuck Harris

Brian Cockburn wrote:

Artekmedia, I'm not sure I understand what you mean by "serial numbers have nothing to do with time". Are serial numbers not monotonically increasing? And I've always assumed that each model has its own serial number sequence, rather than there being one Tek-wide serial number sequence. Does anyone know definitively one way or the other?