M
maxfoo
Guest
On 1 Jan 2006 12:49:22 -0800, "Too_Many_Tools" <too_many_tools@yahoo.com> wrote:
Yeah, the 7000's make great boat anchors too
A
Andy Cuffe
Guest
Well, it's easy compared to other solid state portable Tek scopes.
Its main advantage is far fewer impossible to find custom parts like
all the later solid state scopes.
Andy Cuffe
acuffe@gmail.com
T
Too_Many_Tools
Guest
Actually this raises the next question that I was going to ask...."What
is the easiest Tek scope to work on?"
As I have mentioned before I tend to favor the 5000/7000 line because
of the flexibility but my options are open for the next purchase.
I have mentioned that the newer used Tek scopes I have looked into did
not seem to have repairability designed into them. I have also heard of
more than a few horror stories of parts being unobtainable.
TMT
is the easiest Tek scope to work on?"
As I have mentioned before I tend to favor the 5000/7000 line because
of the flexibility but my options are open for the next purchase.
I have mentioned that the newer used Tek scopes I have looked into did
not seem to have repairability designed into them. I have also heard of
more than a few horror stories of parts being unobtainable.
TMT
P
PaulCsouls
Guest
On Mon, 02 Jan 2006 07:21:22 -0800, Bill Turner <noway@nohow.com>
wrote:
to work. Is there a web site or a book that would help me get it going
again?
Thanks
PaulC
wrote:
I just had a 485 go flaky. I had to push on the front cover to get it
to work. Is there a web site or a book that would help me get it going
again?
Thanks
PaulC
R
Rich Grise
Guest
On Sun, 01 Jan 2006 12:49:22 -0800, Too_Many_Tools wrote:
then the only consideration should be your budget. Then get the
toppest-of-the-line you can afford.
Have Fun!
Rich
If Tektronix scopes are still as good as I've always known them to be,
then the only consideration should be your budget. Then get the
toppest-of-the-line you can afford.
Have Fun!
Rich
T
Too_Many_Tools
Guest
"Yeah, the 7000's make great boat anchors too "
Actually the size has never bothered me.
If you look at the footprint a 7000 series scope takes and then compare
it to the space taken up by a supposely "portable" Tek scope, there is
little difference.
Also since my scope rarely leaves my test bench, the weight difference
(which is small) does not matter.
What does matter is dependability, reliability and cost....all factors
that the newer Tek scopes seem to fail at.
TMT
"Actually the size has never bothered me.
If you look at the footprint a 7000 series scope takes and then compare
it to the space taken up by a supposely "portable" Tek scope, there is
little difference.
Also since my scope rarely leaves my test bench, the weight difference
(which is small) does not matter.
What does matter is dependability, reliability and cost....all factors
that the newer Tek scopes seem to fail at.
TMT
P
Paul Burridge
Guest
On Mon, 02 Jan 2006 08:24:23 GMT, john_c@tpg.com.au (John Crighton)
wrote:
particular case, John...
How to FIX the Fuzzy/Wide Trace on Your Tek 465 or 475 Scope!
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Cleaning the Volts/Div Attenuator Switch Contacts in Tektronix 4XX
Oscilloscopes
--------------------------------------------------------------------------------
It might work wonders for your classic Tektronix 400-series scope.
And you can probably do it yourself, even if you've never opened a
scope, before!
(C) Copyright 2004, by Thomas P. Gootee
--------------------------------------------------------------------------------
Here is a copy of the procedure that I sent to a guy with a Tek 475
that had a fuzzy trace, and "distorted" when he adjusted the volts/div
knob. His original email is below, followed by my reply.
--------------------------------------------------------------------------------
--------- Original message --------
From: "Mike D"
To: "tomg@fullnet.com"
Date: 01-30-03 08:41
Do you repair scopes? I have a tek 475 that powers up but is very
fuzzy and distorts when adjusting the volts/division knob.
I don't know if its worth repairing or if you can reccomend a better
scope from your stock for a comparable price.
Thank You
Mike
--------------------------------------------------------------------------------
Mike,
Yes. I do repair *lots* of oscilloscopes. I do it mainly for in-house
instruments that are to be resold. But, I also do it occasionally on a
fee-for-service basis.
The symptoms you describe sound familiar and it sounds like a pretty
easy repair job, which I could complete for $50. However, depending on
your location, if you are in the continental USA, the shipping could
be $20 to $30 or more, each way.
So, let me tell you what I would try first and maybe you can do it
yourself. (I'd hate to see someone spend more than $100 for something
that they might be able to do in less than 30 to 60 minutes.)
Without seeing the scope myself, I could easily be wrong. But, from
your description, my opinion is that, most-likely, the switch contacts
in the volts/div attenuators (and/or also in the trigger-view and
bandwidth-limiter) are dirty or oxidized.
They are very easy to get to and to clean. And, although it might
sound a little daunting to a first-timer, it really isn't difficult at
all, requires only very-basic tools and supplies, and will probably
work wonders for your scope's performance.
Here is the basic procedure:
Unplug the scope and place it on a large, flat, smooth surface, such
as a table or floor.
Remove the scope's case: Start by removing the four screws in the rear
panel's cord-wrap feet. They may be either Phillips-head or "star"
(Torx) types. The feet may come off along with the screws. There are
usually also two other screws, near the top and bottom of the rear
panel, in the center. Remove them, too. After all six of the screws
have been removed, rotate the carry-handle up and out of the way of
the front panel, probably to the "straight up" position.
It is recommended that you stand the scope on its front panel end and
pull the case up and off. But, if you DON'T have a front panel COVER,
you can either try it anyway, hopefully on a padded surface (and
carefully!), or else just leave the scope sitting on its feet.
From the rear of the scope, with your fingers on the sides of the
case, push on the rear panel with your thumbs. If the scope is not
standing on its front panel end, you will need to be very careful, as
the scope slides out of the case, to also support the front end,
keeping it up, so the bottom front edge of the case does not damage
any of the internal parts of the scope by scraping against them.
Note that if the scope's CASE is DENTED, especially if it's dented on
a corner-edge, it could be *VERY* difficult to remove the scope from
its case! It might then require *QUITE* A BIT of brute force, pushing
on the rear panel (or pulling on the edges of the front panel) and
pulling on the rear edges (or pushing on the front edges) of the case.
(Sometimes, in that situation, it helps to alternate between trying to
move the left and right sides; and maybe even also to alternate
between moving the top and bottom.)
After the scope is out (whew!), see the note in the next paragraph,
and then carefully stand the scope on its SIDE, so that the vertical
board, on the side of the scope, behind the v/div knobs, is facing UP.
NOTE! I usually try to lift and move the scope's internal assembly
ONLY by the edges of the front panel (or CRT bezel) and rear panel, or
other solid structural/steel parts. And be careful not to set the
scope on any objects or uneven surfaces that might touch any of the
internal components.
Just behind the volts/div knobs, inside the scope, there are two
silver, metal "boxes", which house the attenuator/switch assemblies.
Remove all of the necessary screws to open the top of one of the
boxes. (Do only one box at a time.)
Inside the box, there are four little rectangular, plastic "attenuator
modules", each usually labeled with "somenumber X" (e.g. "4X"). Using
a longnose pliers, or something similar (or whatever works), grasp one
of them and pull *straight* up, to remove it. I'm not sure if they're
static-sensitive, or not. But, just in case they are, I would lay it
either on an all-metal part of the scope, or on a piece of aluminum
foil, or something like that (i.e. on bare metal), with the pins
facing down.
I usually only remove one attenuator module at a time, just so I don't
get them mixed up. But you could do two at a time, if it's more
convenient (which it often is).
While looking at the area of the circuit board where the attenuator
module came from, rotate the corresponding v/div switch back and
forth, until you can see which positions raise and lower the tiny gold
U-shaped double-contact sets, up and down, from/to the circuit board.
Cut a small piece of clean, white paper, as lint-free as possible,
into a thin strip, a little wider than one set of contacts, and long
enough for you to handle/manipulate (probably something like three or
four inches long and 3/16"-or-so wide?). Do not use cloth, which might
snag, or anything abrasive. (You may need to cut new pieces,
periodically, as you go through this procedure.)
Turn the volts/div knob, to raise the set of contacts that you're
about to clean, up and away from the board.
Carefully slide one end of the paper under the contacts.
Apply a drop or two (or three) of isopropyl (rubbing) alcohol to the
paper, under the contacts. It's OK to get it on the contacts, board,
etc, too. I assume that the more concentrated the isopropyl is, the
better. But I've had good results using the plain 70% drugstore type,
and the 90% drugstore type. (The results would probably be even better
if you use Caig's "De-Oxit" product, for the cleaning, followed by
Caig's "Pro-Gold". They're available at Caig's Website.)
Immediately turn the volts/div switch so that the contacts are lowered
against the paper and then (carefully!) pull the paper *straight* out
from under the contacts. This should probably be repeated several
times for each set of contacts.
Be careful. If you bend the contacts, you may be in trouble. And they
are *quite* fragile. But, it should be fine as long as you try to pull
the paper as parallel to the board as possible. Certainly, don't ever
pull straight *upward* on it, and not even more upward than sideways.
Also, NOTE that a couple of the contact-pairs, the two that are
nearest to the front of the scope, are raised and lowered by the
AC/GND/DC lever-switch, instead of by the volts/div switch.
When all of the visible contacts have been cleaned that way, replace
the attenuator module, carefully, by pushing its pins back into the
holes in the circuit board and then pushing it all the way in. (It
might not hurt to also clean the attenuator module's pins, although
I've never needed to, nor tried to.)
[If you *DO* happen to have some of Caig's "De-Oxit" product, it might
be good to apply a tiny amount to each pin of each attenuator block. I
usually also apply it to the metal shield, wherever it makes contact
with the screws or their mountings (and the the screw-posts/mountings
themselves), and wherever the shield makes contact with any other
metal surfaces, and also on those metal surfaces themselves. And the
screws themselves should also be treated, as should any nearby
"ground" screws (i.e. loosen, treat/clean, and re-seat). ALSO, make
sure that you treat the grounding "spring" that protrudes up from one
of the screws, where the crew touches it, and on its top where it
touches the scope's case (and also do that part of the inside of the
case). You can often SEE the difference in color of the metal, as the
oxidation is removed, especially if you use the concentrated form of
De-Oxit that comes in the small plastic "needle-dropper" bottle.]
Replace any attenuator modules that won't be in the way, any more.
Then, remove the next attenuator module(s) and repeat the above
procedures, until you've gotten to all of the switch contacts in the
"box".
When one whole channel's switches are done, replace the metal cover
over the attenuator/switch assembly and do the second channel in
exactly the same way (or, what the heck, maybe *better*, if that was
your first time...). [NOTE that the "fingers" that may be on one side
of the shield/box need to go back into the same position that they
were in before the top was removed.]
Now that you know what the tiny, gold switch contacts LOOK like, you
will be able to much-more-easily find the SIMILAR ones that are on the
SAME circuit board, but are toward the REAR of the scope, near the
middle of the board. There is no cover over them. So they're MUCH
easier to get to. There should be one group of four of them and
another group of two of them. Moving the Bandwidth-Limiter and
Trigger-View controls, on the front panel, will raise and lower them.
Clean them in the same way as described above, for the attenuator
switch contacts.
One OTHER thing to check: (I'm not sure, at the moment, if this is
only for the 465 model, or if it also applies to the 475 JUST behind
the metal attenuator/switch shield "boxes", there may be a screw that
connects a metal piece of the box/shield to the circuit board. If that
screw is loose (which I have seen on about a third of the 465 scopes
I've worked on!), or if it doesn't make good contact, you may see very
noticeable effects in the trace(s), such as fuzziness or distortion,
and may see trace-distortion effects when adjusting the trigger-level
control (possibly especially-so at the highest frequencies), and
possibly other triggering problems.
If cleaning the switch contacts doesn't fix the problems you're having
with the "fuzzy" or wide trace, and the attenuator switch anomalies,
further diagnosis and repair may be necessary.
Let me know if you try this, and how it works. If you would still like
me to work on your scope, just let me know.
And let me know if I can be of more help.
Thanks again!
Best regards,
Tom
Tom Gootee
tomg@fullnet.com
http://www.fullnet.com/u/tomg
--
"What is now proved was once only imagin'd" - William Blake
wrote:
I came across this on the 'net, which may or may not be useful in your
particular case, John...
How to FIX the Fuzzy/Wide Trace on Your Tek 465 or 475 Scope!
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Cleaning the Volts/Div Attenuator Switch Contacts in Tektronix 4XX
Oscilloscopes
--------------------------------------------------------------------------------
It might work wonders for your classic Tektronix 400-series scope.
And you can probably do it yourself, even if you've never opened a
scope, before!
(C) Copyright 2004, by Thomas P. Gootee
--------------------------------------------------------------------------------
Here is a copy of the procedure that I sent to a guy with a Tek 475
that had a fuzzy trace, and "distorted" when he adjusted the volts/div
knob. His original email is below, followed by my reply.
--------------------------------------------------------------------------------
--------- Original message --------
From: "Mike D"
To: "tomg@fullnet.com"
Date: 01-30-03 08:41
Do you repair scopes? I have a tek 475 that powers up but is very
fuzzy and distorts when adjusting the volts/division knob.
I don't know if its worth repairing or if you can reccomend a better
scope from your stock for a comparable price.
Thank You
Mike
--------------------------------------------------------------------------------
Mike,
Yes. I do repair *lots* of oscilloscopes. I do it mainly for in-house
instruments that are to be resold. But, I also do it occasionally on a
fee-for-service basis.
The symptoms you describe sound familiar and it sounds like a pretty
easy repair job, which I could complete for $50. However, depending on
your location, if you are in the continental USA, the shipping could
be $20 to $30 or more, each way.
So, let me tell you what I would try first and maybe you can do it
yourself. (I'd hate to see someone spend more than $100 for something
that they might be able to do in less than 30 to 60 minutes.)
Without seeing the scope myself, I could easily be wrong. But, from
your description, my opinion is that, most-likely, the switch contacts
in the volts/div attenuators (and/or also in the trigger-view and
bandwidth-limiter) are dirty or oxidized.
They are very easy to get to and to clean. And, although it might
sound a little daunting to a first-timer, it really isn't difficult at
all, requires only very-basic tools and supplies, and will probably
work wonders for your scope's performance.
Here is the basic procedure:
Unplug the scope and place it on a large, flat, smooth surface, such
as a table or floor.
Remove the scope's case: Start by removing the four screws in the rear
panel's cord-wrap feet. They may be either Phillips-head or "star"
(Torx) types. The feet may come off along with the screws. There are
usually also two other screws, near the top and bottom of the rear
panel, in the center. Remove them, too. After all six of the screws
have been removed, rotate the carry-handle up and out of the way of
the front panel, probably to the "straight up" position.
It is recommended that you stand the scope on its front panel end and
pull the case up and off. But, if you DON'T have a front panel COVER,
you can either try it anyway, hopefully on a padded surface (and
carefully!), or else just leave the scope sitting on its feet.
From the rear of the scope, with your fingers on the sides of the
case, push on the rear panel with your thumbs. If the scope is not
standing on its front panel end, you will need to be very careful, as
the scope slides out of the case, to also support the front end,
keeping it up, so the bottom front edge of the case does not damage
any of the internal parts of the scope by scraping against them.
Note that if the scope's CASE is DENTED, especially if it's dented on
a corner-edge, it could be *VERY* difficult to remove the scope from
its case! It might then require *QUITE* A BIT of brute force, pushing
on the rear panel (or pulling on the edges of the front panel) and
pulling on the rear edges (or pushing on the front edges) of the case.
(Sometimes, in that situation, it helps to alternate between trying to
move the left and right sides; and maybe even also to alternate
between moving the top and bottom.)
After the scope is out (whew!), see the note in the next paragraph,
and then carefully stand the scope on its SIDE, so that the vertical
board, on the side of the scope, behind the v/div knobs, is facing UP.
NOTE! I usually try to lift and move the scope's internal assembly
ONLY by the edges of the front panel (or CRT bezel) and rear panel, or
other solid structural/steel parts. And be careful not to set the
scope on any objects or uneven surfaces that might touch any of the
internal components.
Just behind the volts/div knobs, inside the scope, there are two
silver, metal "boxes", which house the attenuator/switch assemblies.
Remove all of the necessary screws to open the top of one of the
boxes. (Do only one box at a time.)
Inside the box, there are four little rectangular, plastic "attenuator
modules", each usually labeled with "somenumber X" (e.g. "4X"). Using
a longnose pliers, or something similar (or whatever works), grasp one
of them and pull *straight* up, to remove it. I'm not sure if they're
static-sensitive, or not. But, just in case they are, I would lay it
either on an all-metal part of the scope, or on a piece of aluminum
foil, or something like that (i.e. on bare metal), with the pins
facing down.
I usually only remove one attenuator module at a time, just so I don't
get them mixed up. But you could do two at a time, if it's more
convenient (which it often is).
While looking at the area of the circuit board where the attenuator
module came from, rotate the corresponding v/div switch back and
forth, until you can see which positions raise and lower the tiny gold
U-shaped double-contact sets, up and down, from/to the circuit board.
Cut a small piece of clean, white paper, as lint-free as possible,
into a thin strip, a little wider than one set of contacts, and long
enough for you to handle/manipulate (probably something like three or
four inches long and 3/16"-or-so wide?). Do not use cloth, which might
snag, or anything abrasive. (You may need to cut new pieces,
periodically, as you go through this procedure.)
Turn the volts/div knob, to raise the set of contacts that you're
about to clean, up and away from the board.
Carefully slide one end of the paper under the contacts.
Apply a drop or two (or three) of isopropyl (rubbing) alcohol to the
paper, under the contacts. It's OK to get it on the contacts, board,
etc, too. I assume that the more concentrated the isopropyl is, the
better. But I've had good results using the plain 70% drugstore type,
and the 90% drugstore type. (The results would probably be even better
if you use Caig's "De-Oxit" product, for the cleaning, followed by
Caig's "Pro-Gold". They're available at Caig's Website.)
Immediately turn the volts/div switch so that the contacts are lowered
against the paper and then (carefully!) pull the paper *straight* out
from under the contacts. This should probably be repeated several
times for each set of contacts.
Be careful. If you bend the contacts, you may be in trouble. And they
are *quite* fragile. But, it should be fine as long as you try to pull
the paper as parallel to the board as possible. Certainly, don't ever
pull straight *upward* on it, and not even more upward than sideways.
Also, NOTE that a couple of the contact-pairs, the two that are
nearest to the front of the scope, are raised and lowered by the
AC/GND/DC lever-switch, instead of by the volts/div switch.
When all of the visible contacts have been cleaned that way, replace
the attenuator module, carefully, by pushing its pins back into the
holes in the circuit board and then pushing it all the way in. (It
might not hurt to also clean the attenuator module's pins, although
I've never needed to, nor tried to.)
[If you *DO* happen to have some of Caig's "De-Oxit" product, it might
be good to apply a tiny amount to each pin of each attenuator block. I
usually also apply it to the metal shield, wherever it makes contact
with the screws or their mountings (and the the screw-posts/mountings
themselves), and wherever the shield makes contact with any other
metal surfaces, and also on those metal surfaces themselves. And the
screws themselves should also be treated, as should any nearby
"ground" screws (i.e. loosen, treat/clean, and re-seat). ALSO, make
sure that you treat the grounding "spring" that protrudes up from one
of the screws, where the crew touches it, and on its top where it
touches the scope's case (and also do that part of the inside of the
case). You can often SEE the difference in color of the metal, as the
oxidation is removed, especially if you use the concentrated form of
De-Oxit that comes in the small plastic "needle-dropper" bottle.]
Replace any attenuator modules that won't be in the way, any more.
Then, remove the next attenuator module(s) and repeat the above
procedures, until you've gotten to all of the switch contacts in the
"box".
When one whole channel's switches are done, replace the metal cover
over the attenuator/switch assembly and do the second channel in
exactly the same way (or, what the heck, maybe *better*, if that was
your first time...). [NOTE that the "fingers" that may be on one side
of the shield/box need to go back into the same position that they
were in before the top was removed.]
Now that you know what the tiny, gold switch contacts LOOK like, you
will be able to much-more-easily find the SIMILAR ones that are on the
SAME circuit board, but are toward the REAR of the scope, near the
middle of the board. There is no cover over them. So they're MUCH
easier to get to. There should be one group of four of them and
another group of two of them. Moving the Bandwidth-Limiter and
Trigger-View controls, on the front panel, will raise and lower them.
Clean them in the same way as described above, for the attenuator
switch contacts.
One OTHER thing to check: (I'm not sure, at the moment, if this is
only for the 465 model, or if it also applies to the 475
JUST behindthe metal attenuator/switch shield "boxes", there may be a screw that
connects a metal piece of the box/shield to the circuit board. If that
screw is loose (which I have seen on about a third of the 465 scopes
I've worked on!), or if it doesn't make good contact, you may see very
noticeable effects in the trace(s), such as fuzziness or distortion,
and may see trace-distortion effects when adjusting the trigger-level
control (possibly especially-so at the highest frequencies), and
possibly other triggering problems.
If cleaning the switch contacts doesn't fix the problems you're having
with the "fuzzy" or wide trace, and the attenuator switch anomalies,
further diagnosis and repair may be necessary.
Let me know if you try this, and how it works. If you would still like
me to work on your scope, just let me know.
And let me know if I can be of more help.
Thanks again!
Best regards,
Tom
Tom Gootee
tomg@fullnet.com
http://www.fullnet.com/u/tomg
--
"What is now proved was once only imagin'd" - William Blake
P
Phil Hobbs
Guest
John Larkin wrote:
use one with the Polaroid film plate on the front when I was a grad student.
They had a pretty nice analog storage scope whose number I forget--it was a
portable and looked a lot like a 485.
got it for about a fifth of the cost of the overpriced modern version.
LeCroy is selling a 100 GHz sampling scope, which uses the Picosecond Pulse
Labs 100 GHz sampler. Used to be that LeCroy made nice user interfaces but
couldn't build a vertical amplifier to save their lives.
Cheers,
Phil Hobbs
Seconded. That microchannel plate CRT is a thing of great beauty. I used to
use one with the Polaroid film plate on the front when I was a grad student.
They had a pretty nice analog storage scope whose number I forget--it was a
portable and looked a lot like a 485.
I have an 11801A that I use all the time, with the 40 GHz sampling head. I
got it for about a fifth of the cost of the overpriced modern version.
LeCroy is selling a 100 GHz sampling scope, which uses the Picosecond Pulse
Labs 100 GHz sampler. Used to be that LeCroy made nice user interfaces but
couldn't build a vertical amplifier to save their lives.
Cheers,
Phil Hobbs
J
John Crighton
Guest
On 2 Jan 2006 02:50:58 -0800, Winfield Hill
<Winfield_member@newsguy.com> wrote:
In the 1960s Tek did sell a switch servicing kit for the
large dog kennel size 500 series models with wafer
style rotary switches. I remember a pouch containing
several bightly coloured pencil sized applicators of oil,
grease and various cleaning fluids.
"Time to move on" Oh no! I would never get rid of an
instrument for the want of a bit of effort. My 454 is now on
the reserve bench as back up scope number 3 behind a
couple of 465 scopes. My 454 has a nice clip on metal
cover to protect the front panel. This is the scope I am
more comfortable with lending to friends, knowing that
the front panel is not going to get bashed in transit in the
back of a car.
The slight intermittent problem with the timebase switch
is minor, I can live with that. My 454 from the late 60s
has big wafer switches just like the big 500 series scopes
so cleaning these big wafer switches is easy providing
you can get access to them. Access is the problem
in the 454.
Bill Turner mentioned the U shaped contacts in the
465. Yes that was tricky tending to them but they
are getatable. I would never dump a piece of test
gear because of dodgy switches. I just don't have
the heart to dump any test equipment. I should try
and be stronger but I can't. Being a test equipment
nut is a life crippling disease.
Regards,
John Crighton
Sydney
<Winfield_member@newsguy.com> wrote:
In the 1960s Tek did sell a switch servicing kit for the
large dog kennel size 500 series models with wafer
style rotary switches. I remember a pouch containing
several bightly coloured pencil sized applicators of oil,
grease and various cleaning fluids.
"Time to move on" Oh no! I would never get rid of an
instrument for the want of a bit of effort. My 454 is now on
the reserve bench as back up scope number 3 behind a
couple of 465 scopes. My 454 has a nice clip on metal
cover to protect the front panel. This is the scope I am
more comfortable with lending to friends, knowing that
the front panel is not going to get bashed in transit in the
back of a car.
The slight intermittent problem with the timebase switch
is minor, I can live with that. My 454 from the late 60s
has big wafer switches just like the big 500 series scopes
so cleaning these big wafer switches is easy providing
you can get access to them. Access is the problem
in the 454.
Bill Turner mentioned the U shaped contacts in the
465. Yes that was tricky tending to them but they
are getatable. I would never dump a piece of test
gear because of dodgy switches. I just don't have
the heart to dump any test equipment. I should try
and be stronger but I can't. Being a test equipment
nut is a life crippling disease.
Regards,
John Crighton
Sydney
R
Rube
Guest
S
Scott Dorsey
Guest
John Crighton <john_c@tpg.com.au> wrote:
just SEE the insides of the 7000. Likewise the 7000 is a whole lot easier
to work on than the latest generation of digital scopes.
Cramolin with a very long spray tube. You can get it into very small
places without having to do as much dissasembly. But make sure the
contacts are tight, first. I don't see contact cleaning needed on
the scopes of this era, although some of the older ones did.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Everything is relative. If you think the 454 is hard to work on, you should
just SEE the insides of the 7000. Likewise the 7000 is a whole lot easier
to work on than the latest generation of digital scopes.
If the switch wafers really are bad, the easiest thing to do is to use
Cramolin with a very long spray tube. You can get it into very small
places without having to do as much dissasembly. But make sure the
contacts are tight, first. I don't see contact cleaning needed on
the scopes of this era, although some of the older ones did.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
J
John Larkin
Guest
On Mon, 02 Jan 2006 15:41:26 -0500, Phil Hobbs
<pcdhSpamMeSenseless@us.ibm.com> wrote:
me.
ago. I built an ff&f equivalent of his 4208 Camac 1 ns TDC module, at
a customer's request. So he cut his price in half the next time he
bid, specifically to kill me. The customer, bless his heart,
disqualified LeCroy on "technical grounds."
John
<pcdhSpamMeSenseless@us.ibm.com> wrote:
When you start getting powerup timebase errors, which you will, call
me.
I'm still mad at Walter for a dirty trick he pulled about 20 years
ago. I built an ff&f equivalent of his 4208 Camac 1 ns TDC module, at
a customer's request. So he cut his price in half the next time he
bid, specifically to kill me. The customer, bless his heart,
disqualified LeCroy on "technical grounds."
John
S
Scott Dorsey
Guest
On the basic Tektronix thread, I still have this Tek 650HR with a luminance
problem. It appears to be the "PLRT INV & TRIG PICK-OFF" chip, which is
a Tektronix 155-0216-00. Earlier revisions used a Tektronix 155-0032-00.
Tek says support for the monitor (and probably for the rest of the Group 26
products) was discontinued in 1996. They can't tell me what the original
manufacturer's part number is, or even who the original manufacturer of the
chip was, and the service manual lists only the house number.
Any Tek technicians happen to have some of these in the junk box, or know
what the real part number is? The input that takes the base comparison
voltage from the aperture pot is pulling the input way down.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
problem. It appears to be the "PLRT INV & TRIG PICK-OFF" chip, which is
a Tektronix 155-0216-00. Earlier revisions used a Tektronix 155-0032-00.
Tek says support for the monitor (and probably for the rest of the Group 26
products) was discontinued in 1996. They can't tell me what the original
manufacturer's part number is, or even who the original manufacturer of the
chip was, and the service manual lists only the house number.
Any Tek technicians happen to have some of these in the junk box, or know
what the real part number is? The input that takes the base comparison
voltage from the aperture pot is pulling the input way down.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
J
Jim Thompson
Guest
On Mon, 02 Jan 2006 13:58:13 -0800, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:
[snip]
quoted 1/3 what I quoted for a design job.
The potential customer said, "Something's fishy", and gave the
contract to me.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:
[snip]
I've had that happen once. A competing company with nearly 20 staff
quoted 1/3 what I quoted for a design job.
The potential customer said, "Something's fishy", and gave the
contract to me.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice
480)460-2350 | || E-mail Address at Website Fax
480)460-2142 | Brass Rat || http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
R
Roy Lewallen
Guest
Scott Dorsey wrote:
had their own IC design and production facility. So that's the "real"
part number. I don't know of any Tek made ICs for which anyone else
makes an even roughly equivalent part -- if they did, Tek would have
bought them instead of designing and manufacturing their own, which cost
a small fortune.
Roy Lewallen, W7EL
Parts with numbers beginning with 155 are Tek designed and made - they
had their own IC design and production facility. So that's the "real"
part number. I don't know of any Tek made ICs for which anyone else
makes an even roughly equivalent part -- if they did, Tek would have
bought them instead of designing and manufacturing their own, which cost
a small fortune.
Roy Lewallen, W7EL
J
Jim Yanik
Guest
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote in
news:1136230955.431454.299390@g43g2000cwa.googlegroups.com:
width and depth of the instrument!
7K series are LAB scopes,designed for flexibility,along with high
performance.
If you can find a copy,read "Winning With People;The First 40 Years of
Tektronix" by Marshall M. Lee.
Tektronix published it and gave every TEK employee a free copy in 1986.
TEK may still have some copies they might part with,or Ebay at some price.
Or some Beaverton used-book stores!
--
Jim Yanik
jyanik
at
kua.net
news:1136230955.431454.299390@g43g2000cwa.googlegroups.com:
That's because they both were designed to be rack mounted,which limits the"Yeah, the 7000's make great boat anchors too
Actually the size has never bothered me.
If you look at the footprint a 7000 series scope takes and then compare
it to the space taken up by a supposely "portable" Tek scope, there is
little difference.
width and depth of the instrument!
7K series are LAB scopes,designed for flexibility,along with high
performance.
That is because the TEK of today is not the TEK of 1945-1980.
If you can find a copy,read "Winning With People;The First 40 Years of
Tektronix" by Marshall M. Lee.
Tektronix published it and gave every TEK employee a free copy in 1986.
TEK may still have some copies they might part with,or Ebay at some price.
Or some Beaverton used-book stores!
--
Jim Yanik
jyanik
at
kua.net
J
Jim Yanik
Guest
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote in
news:1136224229.374708.216830@g43g2000cwa.googlegroups.com:
No TEK-made ICs,simple switches,low parts count,all solid-state.
(excluding CRT,of course)
Easy to access all parts of the scope,better than any other TEK scope..
--
Jim Yanik
jyanik
at
kua.net
news:1136224229.374708.216830@g43g2000cwa.googlegroups.com:
T921/22 or T932/35,hands down.
No TEK-made ICs,simple switches,low parts count,all solid-state.
(excluding CRT,of course)
Easy to access all parts of the scope,better than any other TEK scope..
--
Jim Yanik
jyanik
at
kua.net
J
Jim Yanik
Guest
Rich Grise <richgrise@example.net> wrote in
newsan.2006.01.02.19.07.27.215209@example.net:
Their "service manuals" have NO component-level schematics or parts lists.
Calibrations are done by PC-based software,and may call for test equipment
you don't have. Power supplies are purchased-parts.
The TDS scopes are engineered to be module-exchange repair only.
--
Jim Yanik
jyanik
at
kua.net
news
an.2006.01.02.19.07.27.215209@example.net:Just do not plan on repairing or calibrating them yourself.
Their "service manuals" have NO component-level schematics or parts lists.
Calibrations are done by PC-based software,and may call for test equipment
you don't have. Power supplies are purchased-parts.
The TDS scopes are engineered to be module-exchange repair only.
--
Jim Yanik
jyanik
at
kua.net
J
Jim Yanik
Guest
kludge@panix.com (Scott Dorsey) wrote in
news:dpc915$do8$1@panix2.panix.com:
you that),and they sold off the IC manufacturing unit to Maxim,who turned
around and stopped making them,as TEK did not buy in the volumes Maxim
wanted.
NO other company makes those 155 or 234 prefixed ICs.
products.You can find them in 465's,IIRC,on the trigger PCB.
Try Ebay,or search electronic salvage companies that sell used TEK
products.
I worked for TEK for 21.5 years as a service tech in their field
offices,repairing and calibrating scopes,TM500,and TV test equipment.
--
Jim Yanik
jyanik
at
kua.net
news:dpc915$do8$1@panix2.panix.com:
155-xxxx-xx and 234-xxxx-xx ICs were made **BY TEK**(they should have told
you that),and they sold off the IC manufacturing unit to Maxim,who turned
around and stopped making them,as TEK did not buy in the volumes Maxim
wanted.
NO other company makes those 155 or 234 prefixed ICs.
The one good thing is that the 155-0032-xx was used in a lot of TEK
products.You can find them in 465's,IIRC,on the trigger PCB.
Try Ebay,or search electronic salvage companies that sell used TEK
products.
I worked for TEK for 21.5 years as a service tech in their field
offices,repairing and calibrating scopes,TM500,and TV test equipment.
--
Jim Yanik
jyanik
at
kua.net
J
Jim Yanik
Guest
kludge@panix.com (Scott Dorsey) wrote in
news:dpc7hl$auo$1@panix2.panix.com:
"service manuals".
vertical preamp PCB,and clean the switch wafers with Tarn-X(also 500 series
scopes),followed by a thorough washing and 3 days in our drying oven.
Eventually,the switch contacts wear enough that they need replacing,or
someone skilled enough to retension all the wafer contacts.
--
Jim Yanik
jyanik
at
kua.net
news:dpc7hl$auo$1@panix2.panix.com:
Yes,the TDS line has no schematics,no circuit descriptions in their
"service manuals".
The 453/454 scopes have silver-plated switches,and I used to pull the
vertical preamp PCB,and clean the switch wafers with Tarn-X(also 500 series
scopes),followed by a thorough washing and 3 days in our drying oven.
Eventually,the switch contacts wear enough that they need replacing,or
someone skilled enough to retension all the wafer contacts.
--
Jim Yanik
jyanik
at
kua.net