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Re: Typo in 2901 SM or wrong value resistor?

 

I just checked two units, B041697 and B041608. They both have 1k 5% carbon resistors.

George

On Mar 4, 2018, at 6:48 AM, Dave Daniel <kc0wjn@...> wrote:

I took a look and that's what I see. The R364 on the divider board is a 1k resistor and the manual calls out a 100 ohm resistor.

DaveD

On 3/3/2018 6:32 PM, Brian Bloom via Groups.Io wrote:
I'm replacing out-of-tolerance resistors in my 2901 time mark gen and ran across a 1k resistor where the SM says it should be 100R. The resistor in question is R364 on the divider board directly behind Q347. This isn't a model number dependent resistor, but my SN is B041433.

Does anyone have a 2901 they can pop the top on and have a look?

Thanks,
Brian





Re: Another 455 bad HV multiplier ?

 

On 2/21/18 12:35 AM, Jeff Woolsey wrote:
I don't see my message detailing earlier progress, so I'll mention it
here.?? I replaced the cap in the inside corner of the HV cage (the old
one had an ESR of 140 ohms).? Doing this brought back all the low
voltages (-5, +5, +32), except +95, which is about 12V now.? The 51V
line on the rear inner fuse is normal now, too, without the hideous
ripple that dragged it to near 0V.? Instead it has 400mV of ripple.?
Probably not to worry about.?? The scale illumination works, and the
calibrator is working too.
I found the thing that lost its magic smoke:? R553, 100R to ground.?
Something tells me I'll fry it again if I replace it.? Indeed, it did.?
So what's causing that?


--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire


Diode 5082-2068 Substitute or Source

 

Hello the Forum, this number looks like an HP part number but these are used
in the FG503 Tektronix Function Generator. It is a silicon "hot-carrier" diode. I
have a bad one. What is a good substitute? What are the specs?

Stan


Re: 7D20 pull tab

 

At a glance it seems quite different, but maybe I can construct a hybrid.

On 4 Mar 2018, at 22:46, Dave Daniel <kc0wjn@...> wrote:

I seem to recall that someone on this list was or is making pull tabs for 7000-series plug-ins.

DaveD

On 3/4/2018 3:41 PM, Dave Voorhis wrote:
I snapped the pull tab on my 7D20. The knob is intact, but the plastic to which it attaches, isn¡¯t. Anybody parting out a 7D20 and willing to sell the plastic tab?


Re: 7D20 pull tab

 

I seem to recall that someone on this list was or is making pull tabs for 7000-series plug-ins.

DaveD

On 3/4/2018 3:41 PM, Dave Voorhis wrote:
I snapped the pull tab on my 7D20. The knob is intact, but the plastic to which it attaches, isn¡¯t. Anybody parting out a 7D20 and willing to sell the plastic tab?


7D20 pull tab

 

I snapped the pull tab on my 7D20. The knob is intact, but the plastic to which it attaches, isn¡¯t. Anybody parting out a 7D20 and willing to sell the plastic tab?


Re: Tekmate floppy setup problem.

 

Hi,

No, I don't think so. All 3 drives i tested are TEAC FD-235HF, which should
be the factory installed ones in the TekMate, and they are 1.44 as far as I
can tell. The TekMate specification also mentioned 1.44 drives. I'm using
HD floppies. But I can try setting it to 720k and use a SD disk just to
make sure.

Szabolcs


2018-03-04 20:18 GMT+01:00 Dave Casey <polara413@...>:

Are you using 1.44MB disks in 720kB drives?

Dave Casey

On Sun, Mar 4, 2018 at 10:35 AM, Szabolcs Szigeti <szigiszabolcs@...
wrote:

Hi,

Now here is an interesting problem. I have two 2402A Tekmates, for my
2440
and 1430a. I was using one of them with an USB floppy emulator, which
works
just fine. I have actually never used the floppy drives (both have HDDs),
but I finally did find my stack of 3 1/2 floppies, so I wanted to try and
use the floppy on the other one, as it is way more col thank the cheep
USB
emulator :-), and it did not work. It accesses it, but then gets an
abort-retry-fail. Ok, no problem, probably the drive is bad. Swapped to
an
other one, the one that actually came out of the other Tekmate, when I
installed the USB drive. That didn't work either. Hmmm. Get a 3rd drive,
no
luck. Now let's try the floppies in the other Tekmate. They don't work
either!

I really don't believe that I have 3 failed drives, and the controllers
are
OK, because the emulator works. Scoping the drive line don't show
anything
out of order, I see the data coming, drive rotates, head moves, etc. So
the
only thing I can think is that there has to be some BIOS or whatever
setting about the size/type that was lost when the NVRAM battery failed.
I
have hacked in external batteries, so that is ok. Obviously, the drive is
set up as a 1.4M drive in the setup.

Am I missing something? Is there any other setting that needs to be
there?
I really don't believe that all 3 drives are bad, but unfortunately I
don't
have any other means to test. I have already swapped cables, drives, even
controller chips.
Not a big problem, but it is bugging me now.

Thanks,

Szabolcs






Re: Tekmate floppy setup problem.

 

Are you using 1.44MB disks in 720kB drives?

Dave Casey

On Sun, Mar 4, 2018 at 10:35 AM, Szabolcs Szigeti <szigiszabolcs@...>
wrote:

Hi,

Now here is an interesting problem. I have two 2402A Tekmates, for my 2440
and 1430a. I was using one of them with an USB floppy emulator, which works
just fine. I have actually never used the floppy drives (both have HDDs),
but I finally did find my stack of 3 1/2 floppies, so I wanted to try and
use the floppy on the other one, as it is way more col thank the cheep USB
emulator :-), and it did not work. It accesses it, but then gets an
abort-retry-fail. Ok, no problem, probably the drive is bad. Swapped to an
other one, the one that actually came out of the other Tekmate, when I
installed the USB drive. That didn't work either. Hmmm. Get a 3rd drive, no
luck. Now let's try the floppies in the other Tekmate. They don't work
either!

I really don't believe that I have 3 failed drives, and the controllers are
OK, because the emulator works. Scoping the drive line don't show anything
out of order, I see the data coming, drive rotates, head moves, etc. So the
only thing I can think is that there has to be some BIOS or whatever
setting about the size/type that was lost when the NVRAM battery failed. I
have hacked in external batteries, so that is ok. Obviously, the drive is
set up as a 1.4M drive in the setup.

Am I missing something? Is there any other setting that needs to be there?
I really don't believe that all 3 drives are bad, but unfortunately I don't
have any other means to test. I have already swapped cables, drives, even
controller chips.
Not a big problem, but it is bugging me now.

Thanks,

Szabolcs




Tekmate floppy setup problem.

 

Hi,

Now here is an interesting problem. I have two 2402A Tekmates, for my 2440
and 1430a. I was using one of them with an USB floppy emulator, which works
just fine. I have actually never used the floppy drives (both have HDDs),
but I finally did find my stack of 3 1/2 floppies, so I wanted to try and
use the floppy on the other one, as it is way more col thank the cheep USB
emulator :-), and it did not work. It accesses it, but then gets an
abort-retry-fail. Ok, no problem, probably the drive is bad. Swapped to an
other one, the one that actually came out of the other Tekmate, when I
installed the USB drive. That didn't work either. Hmmm. Get a 3rd drive, no
luck. Now let's try the floppies in the other Tekmate. They don't work
either!

I really don't believe that I have 3 failed drives, and the controllers are
OK, because the emulator works. Scoping the drive line don't show anything
out of order, I see the data coming, drive rotates, head moves, etc. So the
only thing I can think is that there has to be some BIOS or whatever
setting about the size/type that was lost when the NVRAM battery failed. I
have hacked in external batteries, so that is ok. Obviously, the drive is
set up as a 1.4M drive in the setup.

Am I missing something? Is there any other setting that needs to be there?
I really don't believe that all 3 drives are bad, but unfortunately I don't
have any other means to test. I have already swapped cables, drives, even
controller chips.
Not a big problem, but it is bugging me now.

Thanks,

Szabolcs


Re: Can I install a 2465B motherboard in a 2445B chassis? What will I get?

 

Walter Scott :-)

On 4 Mar 2018, at 15:30, Chuck Harris <cfharris@...> wrote:

The ROM's on the A5 board contain everything they need to
know about being a 2467B, 2465B, 2445B, or 2455B.

The A5 controller's are interchangeably the same. You can
take one out of any member of the 24[4,5,6]5A or B family,
and swap around. The only significant difference has to do
with the separate Display board on A's, and early B's. You
can swap a controller/display board from an A into a late B,
and vice versa, if you want... [The "A" controllers have some
ROM omissions for the extra diddly stuff that the "B" can do,
and some changes in the calibration routines, battery voltage
sensing...]

The way the A5 controller knows what scope you have is by
reading the P/J512, pin 11, and pin 32. Pin 11 goes with
a jumper, W120, which if missing is a 2445B/2455B, if grounded,
is a 2465B.

P32 determines whether the scope is a 2465B, or a 2467B. The
significant difference (board wise) between a 65, and a 67, is
the HV power supply board, the 67 board has the control voltages
necessary for the MCP. As a result, the 67 Board grounds P32,
and passes the signal through the A1 motherboard to P/J512, P32,
on the A5 Controller board.

The only schematic where Tektronix forgot to erase this information
is the analog control <2> schematic for B050000 and above in the
2465B/2467B manual (070-6863-01).

Someone once said: "What a tangled web we weave, when first we
practice to deceive." One of the girl poets, as I recall. Emily
Dickinson maybe?

I hope you won't use this information for evil.

-Chuck Harris

Raymond Domp Frank wrote:
On Sat, Mar 3, 2018 at 02:59 pm, Sergey Kubushyn wrote:


A5 ROM has nothing to do with calibration -- that is stored in NVRAM -- but
it adds those higher sweep rates that 2445B doesn't have i.e. it changes the
scope identity.
ISTR that enabling 500 ps/div horizontal speed to a 2445B just takes adding a jumper near the edge of the main board, at one of the connectors. Sorry, don't remember exactly where and I have no doc. where I am at the moment. I trust this'll ring a bell with someone on this forum who has the details.

Raymond


Re: Can I install a 2465B motherboard in a 2445B chassis? What will I get?

Chuck Harris
 

The ROM's on the A5 board contain everything they need to
know about being a 2467B, 2465B, 2445B, or 2455B.

The A5 controller's are interchangeably the same. You can
take one out of any member of the 24[4,5,6]5A or B family,
and swap around. The only significant difference has to do
with the separate Display board on A's, and early B's. You
can swap a controller/display board from an A into a late B,
and vice versa, if you want... [The "A" controllers have some
ROM omissions for the extra diddly stuff that the "B" can do,
and some changes in the calibration routines, battery voltage
sensing...]

The way the A5 controller knows what scope you have is by
reading the P/J512, pin 11, and pin 32. Pin 11 goes with
a jumper, W120, which if missing is a 2445B/2455B, if grounded,
is a 2465B.

P32 determines whether the scope is a 2465B, or a 2467B. The
significant difference (board wise) between a 65, and a 67, is
the HV power supply board, the 67 board has the control voltages
necessary for the MCP. As a result, the 67 Board grounds P32,
and passes the signal through the A1 motherboard to P/J512, P32,
on the A5 Controller board.

The only schematic where Tektronix forgot to erase this information
is the analog control <2> schematic for B050000 and above in the
2465B/2467B manual (070-6863-01).

Someone once said: "What a tangled web we weave, when first we
practice to deceive." One of the girl poets, as I recall. Emily
Dickinson maybe?

I hope you won't use this information for evil.

-Chuck Harris

Raymond Domp Frank wrote:

On Sat, Mar 3, 2018 at 02:59 pm, Sergey Kubushyn wrote:


A5 ROM has nothing to do with calibration -- that is stored in NVRAM -- but
it adds those higher sweep rates that 2445B doesn't have i.e. it changes the
scope identity.
ISTR that enabling 500 ps/div horizontal speed to a 2445B just takes adding a jumper near the edge of the main board, at one of the connectors. Sorry, don't remember exactly where and I have no doc. where I am at the moment. I trust this'll ring a bell with someone on this forum who has the details.

Raymond


Re: Typo in 2901 SM or wrong value resistor?

 

I took a look and that's what I see. The R364 on the divider board is a 1k resistor and the manual calls out a 100 ohm resistor.

DaveD

On 3/3/2018 6:32 PM, Brian Bloom via Groups.Io wrote:
I'm replacing out-of-tolerance resistors in my 2901 time mark gen and ran across a 1k resistor where the SM says it should be 100R. The resistor in question is R364 on the divider board directly behind Q347. This isn't a model number dependent resistor, but my SN is B041433.

Does anyone have a 2901 they can pop the top on and have a look?

Thanks,
Brian


Re: Can I install a 2465B motherboard in a 2445B chassis? What will I get?

 

On Sat, Mar 3, 2018 at 02:59 pm, Sergey Kubushyn wrote:


A5 ROM has nothing to do with calibration -- that is stored in NVRAM -- but
it adds those higher sweep rates that 2445B doesn't have i.e. it changes the
scope identity.
ISTR that enabling 500 ps/div horizontal speed to a 2445B just takes adding a jumper near the edge of the main board, at one of the connectors. Sorry, don't remember exactly where and I have no doc. where I am at the moment. I trust this'll ring a bell with someone on this forum who has the details.

Raymond


Re: Replacement of Tantalum cap removal of U450??

 

I would probably just clip the leads as you suggested and solder the
new capacitor on from the top of the board instead of messing with it
and risking damage if you are not familiar with removal and assembly.
Wherever possible, I try and pull the leads by leaving a length while clipping, heating and pulling the remaining length, for fear of a remaining piece of wire dropping off inside while soldering the new part on top.

Raymond


Dating a 555

 

I¡¯m trying to approximate the year that my 555 was made. Maybe there¡¯s some way other than just looking at the date codes on components? What I know is the serial number is 601 and the center strip on the scope head is chrome not Tek blue. To be fair I haven¡¯t really poked around too much in the head as I¡¯m working my way the through power supply first. If you have any thoughts or suggestions I¡¯d love to hear them. Oh and the connections are all SO-239 which could be nothing more than an option but I don¡¯t know. Thanks in advance!


Re: 2465B Test 05 Fail 24, can U500 Tek 155-0239-02 replaced by a Tek 155-0239-00 ?

 

All,

I found and ordered a 155-0239-02 at Qservice in Greece, so it should be in Spain and OK by the end of the week.

Un saludo,

Leo


Re: App Notes

 

About a repository... that's a good question for the group.
Each of the legacy "hallmark" test equipment manufacturers has gone through a lot of change and transformation.


Re: App Notes

 

Gary
Curious ..... what is the motivation in this day and age for Tektronix to keep a repository of 30+ year old applications notes?
-DC
manuals@...

On 3/4/2018 12:36 AM, Gary Robert Bosworth wrote:
Thank you Ronald. I hope you can find them. Hard to believe they are not readily available through Tektronix. Why can't Tektronix maintain a repository?

Gary

On March 3, 2018, at 9:13 PM, Ronald Carlson <ronald.carlson.54@...> wrote:

Gary,

About 6-7 years ago I found these application notes, or most of them, online. Some are definitive tutorials and give procedures directly applicable to the J16 and its many probes. Pg 7 of the 1981 revision of the instruction manual provides the titles of the application notes. As I recall, I found them in an obscure website and am hunting around for them. Will post links with what I find.

Ron




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


Re: App Notes

 

Thank you Ronald. I hope you can find them. Hard to believe they are not readily available through Tektronix. Why can't Tektronix maintain a repository?

Gary

On March 3, 2018, at 9:13 PM, Ronald Carlson <ronald.carlson.54@...> wrote:

Gary,

About 6-7 years ago I found these application notes, or most of them, online. Some are definitive tutorials and give procedures directly applicable to the J16 and its many probes. Pg 7 of the 1981 revision of the instruction manual provides the titles of the application notes. As I recall, I found them in an obscure website and am hunting around for them. Will post links with what I find.

Ron


Re: App Notes

 

WOW did I miss the mark.

First I thought I was replying to the HP group.

Second I see where my website suggestion seems to have disappeared in a huge string of ¡°stuff¡¯.

So, regardless if your interest is HP, TEK or actually numerous other subjects it is worth visiting archive dot org.

Ken

On 3Mar, 2018, at 10:30 PM, ken chalfant <kpchalfant@...<mailto:kpchalfant@...>> wrote:

Greetings,

I am only catching part of this conversation but allow me to suggest: <><>

Applying the search term "Hewlett Packard" brings up an enormous amount of material.

BTW, applying the search term "Tektronix" also delivers amazing results.

Regards,

Ken


On 3Mar, 2018, at 10:13 PM, Ronald Carlson <ronald.carlson.54@...<mailto:ronald.carlson.54@...><mailto:ronald.carlson.54@...>> wrote:

Gary,

About 6-7 years ago I found these application notes, or most of them, online. Some are definitive tutorials and give procedures directly applicable to the J16 and its many probes. Pg 7 of the 1981 revision of the instruction manual provides the titles of the application notes. As I recall, I found them in an obscure website and am hunting around for them. Will post links with what I find.

Ron