Photo Album Search Capability
I have requested that Groups.io provide a search capability for the photo
albums.
This seems like a simple request since the albums are already in
alphabetical order and since they already provide search capability for many
other things.
Dennis Tillman W7PF
TekScopes Moderator
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Re: Tek 7623A - Lowest HF Step response adjustment issue (Mid Frequency Lacking)
Albert, Thanks for the heads up... my remarks just after your quote. On Fri, Mar 30, 2018 at 01:12 pm, Albert Otten wrote: Fabio, 151-0271-00 is not a matched pair, so Tek didn't judge that necessary .
20 mV difference is not important at all since these transistors are current
driven at the emitter. The transistors in the previous pair Q2405/2505 have
(or should have) enough headroom in Vce (maybe check this). This also explains
that you see no difference in collector signal. Difference in hfe could do
more harm perhaps, though I also doubt this.
A suitable replacement would be 2N4261. Sphere has a few new in stock under
151-0434-00, $6 each. In the cross ref also listed as 151-0271-00. As you will see on my other reply to Roger, I managed to make the proper vertical LF step response right, by using the LF adjustments there are on the vertical plugin. Those transistors though, seem to have become less important (but opportunely, I will try to find a replacement). I also found, on the Tek semiconductor x-ref, that there seem to be a difference between the part 151-0271-00 and the 151-0434-00. While the latter is indeed a direct equivalent to the 2N4261, it seems the 151-0271-00 is a variation of the 4261, which they called the A5T-4261. The a5T kind is an 80mA Ic part, while the vanilla 2n4261 is a 30mA part. The A5T has a TO-92 package and seems also to be capable of dissipating more power as well (0.5W against 0.2W the TO-72A package of the 2n4261). Krgrds, Fabio
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Re: 453 scope fan wiring help needed!
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Re: tek part number Prefixes
Hi Bob,
I had no idea it was in there. It is in my 1982 Materials Catalog as well. It is buried in there between different materials where I would never have found it if you hadn't mentioned it.
When you upload the lists be sure to send a copy to Kurt at TekWiki so he can put it up there.
Dennis Tillman W7PF
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Robert Hay Sent: Sunday, April 01, 2018 10:30 PM To: [email protected]Subject: Re: [TekScopes] tek part number Prefixes I have the 1984 materials catalog which has alphabetical and numerical lists. 119-0000-00 comprises misc electrical components (delay lines, filter chopper, oscillator, power supply, fan, etc.). Another list I saw included flexible media. I thought I uploaded those lists to the files area - if not I will in the next day or so. Bob. On 4/1/2018 9:04 PM, Dennis Tillman W7PF wrote: Hi Shaun
Thanks for the link to Kurt's web pages. He adds so much new useful stuff to it so fast it makes my head spin. It is hard to keep up with what he has there.
Dennis Tillman W7PF
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
Shaun M
Sent: Sunday, April 01, 2018 7:20 PM
To: [email protected]
Subject: Re: [TekScopes] tek part number Prefixes
Dennis,
According to the list on the Wiki, 119- comprises "Assemblies". The
most comprehensive list of Tek prefixes I have come across is here:
(Thanks Kurt)
Shaun Merrigan -- Dennis Tillman W7PF TekScopes Moderator
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Re: 453 scope fan wiring help needed!
This is a Permanent Split Capacitor motor. The cap, which is used all the time, not just for starting, causes a phase shift in its associated winding, which makes part of the overall magnetic field appear to rotate instead of just vibrating back and forth. Shaded-Pole motors do the same thing, less efficiently, with a shorted turn around part of the pole pieces. I can see two uses for a fourth wire. It could be safety ground, or there could be two wires - possibly a separate winding - for the cap instead of one tap and one end. If you have a wire too short to reach, I guess it's moot. I too was upset by the noise of my (three-wire) fan, and after bearing replacement which made no difference, and cushion-mounting which didn't make enough difference to satisfy, I retrofitted a computer tubeaxial fan, which is less obnoxious and moves more air. I love it. I posted my experience in "453 fan bearings", and pictures in "453-454 Tubeaxial Fan Retrofit" at /g/TekScopes/album?id=12878. Regards, Dave Wise ________________________________________ From: [email protected] < [email protected]> on behalf of Phillip Potter <p.potter@...> Sent: Friday, March 30, 2018 6:17 PM To: [email protected]Subject: [TekScopes] 453 scope fan wiring help needed! Hi all, The fan on my scope was very noisy, so I pulled the back apart and got the fan apart from the shroud, only to find that the wiring is soldered in with no way to get the fan out to work on it. So.... I cut the wires. Now, in the process of returning it to the scope, I've been reconnecting the wires, BUT in my clumsy style I managed to pull the shortest of the four (the black one) out of the back while attempting to strip it! Grrrr. So, now I can't tell where the wire connects to the scope! I have three different schematics (manuals) and NONE of the three show a fan with FOUR wires!!! Only three...... What the heck?!? Is there anyone here who can shed some light on what I should do now? That is... after I shoot myself! Thanks in advance for anything you can suggest. Phil
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Re: Tek 7623A - Lowest HF Step response adjustment issue (Mid Frequency Lacking)
Hello Roger, Apologies for the long delay for feedback... I was getting my hands dirty on the thing. See my comments right after yours... I have just checked on my 7A26 and the Low Frequency Compensation (attenuator)
adjustments do have about the correct time constant to correct for your 3usec
lag in response (I only checked one of the attenuator settings, 0.1V and
C114,C115). You could try using the 7A26 LF compensation to flatten the 1 -
3usec region before going back to the mainframe adjustments for the higher
frequency components. I am sure you can see why the standardizer plugin is
useful - you have HF compensation both in the mainframe and the plugins. I confess that when I read your message, my first reaction was to dismiss your suggestion, because you meant adjusting the input attenuator, and since I am using - on purpose - a 25mVpp signal, I am using the 5mV/div range, which doesn't engage any attenuator that I could compensate for. But, your message did trigger my curiosity about what could possibly be the AC frequency compensation adjustments on the plugin and - bingo - besides the attenuators (which were ruled out), the 7A26 has not one, but two LF response adjustments, R1436+C1436 with average time constant of 150us, and R1431+C1431 with avearge time constant of 5.5us. And not surprisingly, those 2 adjustments together, in combination with the lowest frequency response adjustment of the MF's vertical amplifier, have plenty of room for correcting the low / mid frequency lacking that I was finding. I think the sharp 'knee' you have shown on the YT video is due to trying to
correct the low frequency error in the plugin with the HF adjustments in the
mainframe. Adjusting the lowest frequency / latest time errors first reduces
the interaction between the adjustments. Yes, I always try to go from LF to HF, but I was kind of blinded by the fact that the signal I was seeing (at the plugin's output) was free of that LF lacking, so I was convinced that I had to pursue the solution at the MF's amplifier alone. But the bottom line is, I don't have experience enough with the 7000 family to know what would be a correctly looking signal at the plugin's output, never mention that my test rig was less than ideal in this case, looking at only one side of the balanced output, with a long ground lead... my assessment of the "correct" signal coming out of the plugin was, at least, subjective. I hope I am helping rather than adding confusion, best wishes, Not at all, your suggestion pointed me in the right direction and I managed to get the overall vertical step response well adjusted. I`m not getting (yet) a step response as fast as I managed to get from my 464 of 3.5ns... I can only get to 4ns, but I may still be getting confused about the great number of adjustments there are (between the MF and the Vertical plugin), and the almost infinite possible combinations... But I`m happy for now... Good enough for government's work! There are a few other issues that are bugging me (on the horizontal axis... an intermittent jitter), and I will pursue that first, before trying to perfect the vertical any further... but that's subject for another post. Rgrds, FT
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Re: TDS5xx, 6xx, & 7xx Series scope history
Thanks for that, pretty cool. My two 754's were originally delivered to Texas Instruments and Virginia PolyTech University. The newer one was delivered in April '99 -? it's a B032XXX. So looks like they delivered about 3,000 units per year at the end.
--Eric
Sent from my Samsung Galaxy S8.
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-------- Original message --------From: "David G." <d.garrido@...> Date: 4/2/18 9:04 AM (GMT-06:00) To: [email protected] Subject: [TekScopes] TDS5xx, 6xx, & 7xx Series scope history Hello All, Today I was doing some research about a TDS754D and found that you could go to the TEK website and run a search for the model number and serial number.? The info provided will tell you who the scope was originally shipped to and on which date. I was just goofing off and I think the last TDS754D scope was serial number B041827 sold to Rockwell Collins on Dec 31, 2002.? There are no other entries beyond that serial number.? So that begs the question...............could that be the last serial number of this scope produced and sold to a customer? Hope this info helps someone. Cheers, David
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Re: I would like some input on a good wire forming tool.
On Mon, 2 Apr 2018 09:05:54 -0400, you wrote: Chuck,
Thanks.? I figgered they were used for bending leads, I was just unsure
how one utilized those tools.? I've only used smooth needle nosed pliers
of different shapes to put the bend in the components using the TLAR
(That Looks About Right) method of measurement. Those look like handy
little tools to have around. Slide the tool until the outside is just inside the holes for the part on the board. Use that notch. If you have the lead bending tool (the one with the thumbwheel), then there are tips much like a caliper. Use them and you set the lead spacing. There's another tool that is somewhat a combination of the two, and it sets leads and does an inwards crimp to elevate the part. Harvey
Mark
On 04/02/2018 08:42 AM, Chuck Harris wrote:
They are used to bend the leads on an axial
part, that will lay down on the PCB, so that
they will fit the spacing of the holes in the
board.
You put the axial part in the middle of the
guide, with its leads in the lead slots for
the proper hole separation, and then push the
leads down to bend them at 90 degrees to the axis.
There are also pliers that can be adjusted for
width that perform the same function. I have
a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and
the you stick the part in press the clamp trigger,
and bend the wires with your fingers.
I made another tool (back in the day) out of a
cheap pair of needle nosed pliers, that crimped
the resistor leads into a "U" to space them up
from the circuit board... but that is another
story.
-Chuck Harris
Mark Wendt wrote:
On 04/02/2018 03:34 AM, Michael A. Terrell wrote:
Velleman-VTBEND1-Resistor-and-Axial-Component-Lead-Bending-Tool-Set
These are the tools that were in common use when that scope was built. You might
find them cheaper somewhere else, but they are worth the asking price. I've had
mine for about 30 years.
Michael A. Terrell
Never having used something like those, how exactly do you use them?
Mark
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Re: I would like some input on a good wire forming tool.
I've always (50+ years) used one of these:
They no longer sell them but I'm sure others do. I got a bunch on closeout from Travers for 10 cents each!
Vince.
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On 04/02/2018 09:05 AM, Mark Wendt wrote: Chuck,
Thanks. I figgered they were used for bending leads, I was just unsure
how one utilized those tools. I've only used smooth needle nosed pliers
of different shapes to put the bend in the components using the TLAR
(That Looks About Right) method of measurement. Those look like handy
little tools to have around.
Mark
On 04/02/2018 08:42 AM, Chuck Harris wrote:
They are used to bend the leads on an axial
part, that will lay down on the PCB, so that
they will fit the spacing of the holes in the
board.
You put the axial part in the middle of the
guide, with its leads in the lead slots for
the proper hole separation, and then push the
leads down to bend them at 90 degrees to the axis.
There are also pliers that can be adjusted for
width that perform the same function. I have
a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and
the you stick the part in press the clamp trigger,
and bend the wires with your fingers.
I made another tool (back in the day) out of a
cheap pair of needle nosed pliers, that crimped
the resistor leads into a "U" to space them up
from the circuit board... but that is another
story.
-Chuck Harris
Mark Wendt wrote:
On 04/02/2018 03:34 AM, Michael A. Terrell wrote:
Velleman-VTBEND1-Resistor-and-Axial-Component-Lead-Bending-Tool-Set
These are the tools that were in common use when that scope was
built. You might
find them cheaper somewhere else, but they are worth the asking
price. I've had
mine for about 30 years.
Michael A. Terrell
Never having used something like those, how exactly do you use them?
Mark
--
Michigan VHF Corp.
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Re: tek part number Prefixes
That page () is the work of Peter H, who is a very active editor of Tekwiki.
Thanks, Peter!
-Kurt
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TDS5xx, 6xx, & 7xx Series scope history
Hello All,
Today I was doing some research about a TDS754D and found that you could go to the TEK website and run a search for the model number and serial number. The info provided will tell you who the scope was originally shipped to and on which date.
I was just goofing off and I think the last TDS754D scope was serial number B041827 sold to Rockwell Collins on Dec 31, 2002. There are no other entries beyond that serial number. So that begs the question...............could that be the last serial number of this scope produced and sold to a customer?
Hope this info helps someone.
Cheers,
David
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Re: Typefaces in Tektronix manuals, was Re: [TekScopes] Protecting button labels
On 2018-04-01 11:23 PM, snapdiode via Groups.Io wrote: I created an album called "Manual spines typeface".
Oh dear, the albums interface is very very bad... I hope groups.io is working on it... Found the album though: /g/TekScopes/album?id=42121That is an interesting challenge. An extremely condensed gothic that was around the 1950s(?) and 1960s era... Most likely we will only get something "close" and as you already see, there is some variation in the font used for the model numbers (although the TEKTRONIX INC must be consistently used standing artwork). Let me mull over this, the actual faces are probably in long lost photosetting or (in the 50's) metal catalogues, but you'll need something that's easily available in digital today. Luckily there are lots of "similar" modern designs, I'll just have to rummage for them. --Toby I tried with a scanner but of course, the spines are round... and brittle. They'd probably crack if I tried to flatten them.
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Re: I would like some input on a good wire forming tool.
Well, it does bend AND cut both leads so... ;)
Thanks,
Barry - N4BUQ
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Damn.? They're mighty proud of that item aren't they?
Mark
On 04/02/2018 09:12 AM, Craig Sawyers wrote:
Like Chuck, I have one of these
They seem to have got very expensive. 20 years or so, when many more
components were leaded and before
surface mount took over, they were a LOT cheaper. I guess because many more
were manufactured then.
But for populating a board with ~100 resistors they are absolutely
invaluable.
Craig
There are also pliers that can be adjusted for width that perform the
same function. I have a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and the you stick the part in
press the clamp trigger, and bend the wires with your fingers.
|
Re: I would like some input on a good wire forming tool.
Damn.? They're mighty proud of that item aren't they?
Mark
toggle quoted message
Show quoted text
On 04/02/2018 09:12 AM, Craig Sawyers wrote: Like Chuck, I have one of these
They seem to have got very expensive. 20 years or so, when many more components were leaded and before
surface mount took over, they were a LOT cheaper. I guess because many more were manufactured then.
But for populating a board with ~100 resistors they are absolutely invaluable.
Craig
There are also pliers that can be adjusted for width that perform the
same function. I have a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and the you stick the part in
press the clamp trigger, and bend the wires with your fingers.
|
Re: I would like some input on a good wire forming tool.
The largest problem I have found with the plastic
bending guides is they are too large, with the pocket
that the component fits into too small. They worked
very well when component densities were typical of single
or double sided boards, but as densities climbed, they
were useless.
Put another way, they are fine for 1W through 1/4 watt
resistors, but not for 1/8W.
I have had a little better luck with the bending pliers,
with all but the smallest parts.
I used to assemble a lot of through hole assemblies, but
now it is SMD, and my assortment of clipping and bending
tools aren't needed very often.
-Chuck Harris
Mark Wendt wrote:
toggle quoted message
Show quoted text
Chuck,
Thanks. I figgered they were used for bending leads, I was just unsure how one
utilized those tools. I've only used smooth needle nosed pliers of different shapes
to put the bend in the components using the TLAR (That Looks About Right) method of
measurement. Those look like handy little tools to have around.
Mark
On 04/02/2018 08:42 AM, Chuck Harris wrote:
They are used to bend the leads on an axial
part, that will lay down on the PCB, so that
they will fit the spacing of the holes in the
board.
You put the axial part in the middle of the
guide, with its leads in the lead slots for
the proper hole separation, and then push the
leads down to bend them at 90 degrees to the axis.
There are also pliers that can be adjusted for
width that perform the same function. I have
a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and
the you stick the part in press the clamp trigger,
and bend the wires with your fingers.
I made another tool (back in the day) out of a
cheap pair of needle nosed pliers, that crimped
the resistor leads into a "U" to space them up
from the circuit board... but that is another
story.
-Chuck Harris
Mark Wendt wrote:
On 04/02/2018 03:34 AM, Michael A. Terrell wrote:
Velleman-VTBEND1-Resistor-and-Axial-Component-Lead-Bending-Tool-Set
These are the tools that were in common use when that scope was built. You might
find them cheaper somewhere else, but they are worth the asking price. I've had
mine for about 30 years.
Michael A. Terrell
Never having used something like those, how exactly do you use them?
Mark
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Re: I would like some input on a good wire forming tool.
Select the proper notch, insert part and push the leads down until they are parallel to the tool. That set has multiple widths to make it easier than the old design, where you had to center some parts in the gap.
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-----Original Message----- From: Mark Wendt <wendt.mark@...>
Sent: Apr 2, 2018 7:52 AM
To: [email protected]
Subject: Re: [TekScopes] I would like some input on a good wire forming tool.
On 04/02/2018 03:34 AM, Michael A. Terrell wrote:
Velleman-VTBEND1-Resistor-and-Axial-Component-Lead-Bending-Tool-Set
These are the tools that were in common use when that scope was built. You might find them cheaper somewhere else, but they are worth the asking price. I've had mine for about 30 years.
Michael A. Terrell
Never having used something like those, how exactly do you use them?
Mark
Michael A. Terrell
|
Re: I would like some input on a good wire forming tool.
I used a pair of needle nose to bend the leads, prior to find the block. I would simply find out how far from the tip would give the proper length, and bend the leads one at a time, but the block was much faster and put less stress at the bend by using a slightly larger radius.
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Show quoted text
-----Original Message----- From: Chuck Harris <cfharris@...>
Sent: Apr 2, 2018 8:42 AM
To: [email protected]
Subject: Re: [TekScopes] I would like some input on a good wire forming tool.
They are used to bend the leads on an axial
part, that will lay down on the PCB, so that
they will fit the spacing of the holes in the
board.
You put the axial part in the middle of the
guide, with its leads in the lead slots for
the proper hole separation, and then push the
leads down to bend them at 90 degrees to the axis.
There are also pliers that can be adjusted for
width that perform the same function. I have
a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and
the you stick the part in press the clamp trigger,
and bend the wires with your fingers.
I made another tool (back in the day) out of a
cheap pair of needle nosed pliers, that crimped
the resistor leads into a "U" to space them up
from the circuit board... but that is another
story.
-Chuck Harris
Mark Wendt wrote:
On 04/02/2018 03:34 AM, Michael A. Terrell wrote:
Velleman-VTBEND1-Resistor-and-Axial-Component-Lead-Bending-Tool-Set
These are the tools that were in common use when that scope was built. You might
find them cheaper somewhere else, but they are worth the asking price. I've had
mine for about 30 years.
Michael A. Terrell
Never having used something like those, how exactly do you use them?
Mark
Michael A. Terrell
|
Re: I would like some input on a good wire forming tool.
Like Chuck, I have one of these
They seem to have got very expensive. 20 years or so, when many more components were leaded and before
surface mount took over, they were a LOT cheaper. I guess because many more were manufactured then.
But for populating a board with ~100 resistors they are absolutely invaluable.
Craig
toggle quoted message
Show quoted text
There are also pliers that can be adjusted for width that perform the
same function. I have a pair with pointed tips that you turn a thumb
wheel until they fit in the board holes, and the you stick the part in
press the clamp trigger, and bend the wires with your fingers.
|
Re: I would like some input on a good wire forming tool.
Thank you I just hit buy it now on the Velleman VTBEND.
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Re: 7633 fan possible to repair?
[me in the previous message] > " So I was about to give up and replaceD it with a modern/plastic fan, while hunting for a replacement fan, "
Oops, typo, the 'D' should not be there.. I have NOT yet replaced it with a modern fan...
Scary how one tiny little typo can make you look like you are saying nothing less than the absolute opposite of what you actually meant ! ... :-/
Vincent Trouilliez
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Fabio Trevisan
Michael A. Terrell
Vince