Date   

Re: Maybe OT? TELEQUIPMENT CT71

Dave Voorhis
 

On 10 Feb 2021, at 22:41, Stephen <stephen.nabet@gmail.com> wrote:


On Wed, Feb 10, 2021 at 11:32 AM, Dave Voorhis wrote:


On 10 Feb 2021, at 21:54, Stephen <stephen.nabet@gmail.com> wrote:


What do you guys think of this curve tracer compared to other “real” Tek
ones?
What would it compare to in the official Tek line? Is it worth it?
I’ve never used a curve tracer before, and I don’t own one, I’m just
curious.

I have one.

It has neither the range of features or the industrial build quality (or the
storage capability) of my Tek 577 D1, but it’s still a nice, capable curve
tracer.

On the plus side, it has an illuminated graticule, which my 577 doesn’t
have.

Storage?
What kind of features would you say it’s lacking?
Build quality isn’t good? From the pictures it looks like any other good Tek gear to me.
Telequipment that was owned by Tektronix from the late 60’s through the 1970’s, I think. They made relatively low-cost equipment targeted at the service market, rather than the higher-end engineering market targeted by Tek.

Some differences:

The CT71 is technically simpler than the 577 and generally light-weight construction and cheaper circuit boards, lower power (10 watts max compared to the 577’s 100 watts), and a fixed front-end with multiple device adaptors, instead of a front-end plug-in (several available) with multiple device adaptors on the 577.

The 577 has a multi-turn precision vernier for offset and switchable aid/oppose, whereas the CT71 is a standard 1-turn pot and aid-only.

The 577 is switchable 1 - 10 or 1 - 100 (?) steps; the CT71 is 1 - 10 steps only.

The 577 has single-sweep and pulsed modes, which the CT71 doesn’t have.

The 577 D1 (but not the D2 model) has analog storage, which reduces flicker with slow sweeps and allows you to easily observe curve shift over time due to heating and such, which the CT71 doesn’t have.

The 577 has a front-panel circuit breaker to cut out the collector supply if the DUT is shorted; with the CT71 you replace a fuse.

Etc.


Re: CSA, UL/ULC and CE approvals for Tek gear

Michael A. Terrell
 

satbeginner wrote:
Hi Walter,

It could even be worse, a while back in The Netherlands there was a documentary about fake CE approvals.
It looks like CE, but the font is a bit different, and the spacing is a bit wider, and suddenly it means Chinese Export...

https://support.ce-check.eu/hc/en-us/articles/360008642600-How-To-Distinguish-A-Real-CE-Mark-From-A-Fake-Chinese-Export-Mark
Some refer to it as 'Can't Enforce' since there are no numbers to follow to the certification, it is too easy to fake.


Re: Tek 576 - step generator power amp - how to check?

Dave Daniel
 

Thanks for the clarification.

DaveD

On Feb 10, 2021, at 17:50, Chuck Harris <cfharris@erols.com> wrote:

Disgruntled? No, that wasn't it.

Tekscopes was once a fun group that mingled technical discussions
with topical things that happened to strike any member's fancy...
much like it is today, only now maybe to a slightly lesser degree.

The group's owner was away, busy doing other things, including
cultivating a business selling his own brand of snake oil to
audiophools.

Tekscopes was pretty free-wheeling.

There were always members then, as there are members now, that simply
despise any talk of things not tektronix.... Well, unless they are
the ones doing the off topic talking, of course. There were even a
fun few that liked tube scopes, but hated discussion about solid state
scopes... and vice versa, I would suppose...

One pretty day, a thread started that was making fun of audiophoolery,
and one of the self appointed moderators woke the group's owner from
his multiyear slumber, and seeing his market being ridiculed, he took
action.

All told, some 2 dozen members were banned from the group, and
probably an equal number left in support of those banned, myself
included. Many of the banned members were not even involved in the
thread, and many who were involved, weren't banned, leading some to
surmise that some grudges were being settled that day.

We formed tekscopes2 as an alternative to tekscopes, and formally
allowed technical discussions to mingle with off topic discussions.
Our only prohibition was mean behavior, and spamming. Kuba Ober
took the helm initially, and David Partridge took over from him.

When tekscopes's owner got a paying gig with tektronix, running their
blog/user's group, he lost all interest in tekscopes, and accepted
Dennis Tillman's kind offer to take over the day-to-day running
of the group...

Dennis occasionally allows the off-topic chit chat... Hell, he even
starts off topic chit chat... and rules with a wise gentle hand.

His better understanding of the group's dynamics encouraged many
tekscopes2 members (those who hadn't yet died) to come back to
tekscopes.

And, that is where things stand today.

-Chuck Harris, Charter member of tekscopes2

Dave Daniel wrote:
The TekScopes2 group was purportedly started by some TekScopes members who became
disgruntled about something to do with the TekScopes forum. I don't know what
precisely the issue was - it was before I joined either group.

DaveD


On 2/10/2021 4:10 PM, Ozan wrote:
I'll make a copy in the "...2" group.
I meant in the "..." without "2" group... its done.

Here it is: https://groups.io/g/TekScopes/album?id=260560
After seeing the pictures I want my own 576.

What is the difference between TekScopes and TekScopes2 groups?

Ozan








Re: Dark deposit on pins near leaking SMD electrolytic caps

Jim Ford
 

Yeah, I think these days the cost of getting boards fabbed is so cheap that it's hard to justify fabbing your own. I would expect the commercial board shops to charge extra for a 3- or other odd-layer board, if they would even fab it at all. I suppose the FBI, CIA, and other like institutions probably fab their own boards to keep their existence and design away from the public, and some companies may need boards quicker than a few days, so they may do them in-house, but for the most part, it doesn't make sense to do so.

Thanks, Harvey.

Jim

------ Original Message ------
From: "Harvey White" <madyn@dragonworks.info>
To: TekScopes@groups.io
Sent: 2/10/2021 8:22:05 AM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

Back when I was still making PC boards, I pretty much standardized on single sided half thickness (or slightly less) board material. I had registration problems when making boards, and often one side of a DS board would be fine and the other? not.

My boards were match drilled with registration holes, then epoxied together (use the 1 hour type, just trust me....). The project I needed a 3 layer board for was a touch keypad with an atmel processor, the third layer was outside, and had only the touchpads and wiring on it. Connections to the "inner" layer were made through larger holes and bridges, IIRC. The project sorta worked, but atmel's touch library left much to be desired.

If you're going to ever do 4 layer boards, you need to be able to plate through holes, which I never could. Some can, though.

As a side note, the material used in today's PC board material, specifically the epoxy holding the foil on, seems to be a lot more heat tolerant than the epoxy used in the 60's and 70's, which would often lift at the touch of an iron. (not heat controlled, though, such things were difficult to find.)

Harvey


On 2/10/2021 12:41 AM, Jim Ford wrote:
OK. I will change my story to I've never seen 3-layer boards.

Usually when I see something that doesn't make sense, I attribute it to "It must have been less expensive to do it that way."

Thanks, Harvey.

Jim

------ Original Message ------
From: "Harvey White" <madyn@dragonworks.info>
To: TekScopes@groups.io
Sent: 2/9/2021 8:53:30 PM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

Physically, one layer, copper on top.

inner layer (* see note)

outer layer, copper on bottom.

That inner layer can be single sided or two sided, depending. I don't think that anything in the manufacturing process keeps it from being so. I've actually made 3 layer boards, although they're quite awkward without plated through holes.

One side of that inner layer can be missing, so yes, a 3 layer board. I guess it was cheaper to make for some reason, but that was then, long ago (in electron lives) then...

Harvey


On 2/9/2021 11:33 PM, Jim Ford wrote:
3-layer boards? Never heard of them. Maybe you mean 3 dielectric layers and 4 metal layers? PCBs are built up from the inside out, starting with a core (fully cured dielectric sheet plated on both sides with copper foil) and adding more cores and/or prepregs (partially cured dielectric sheet plated on one side with copper) symmetrically on both sides until the stackup is done. Hence there is always an even number of (metal) layers. Always!

Jim Ford

------ Original Message ------
From: "greenboxmaven via groups.io" <ka2ivy=verizon.net@groups.io>
To: TekScopes@groups.io
Sent: 2/9/2021 6:02:16 PM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

The Sonys have three layer boards, I didn't have any problems. However, I can imagine some very bad problems if the electrolyte got into a connection that connects with one of the inner layers. How would you deal with that?

Bruce Gentry, KA2IVY


On 2/9/21 20:44, Raymond Domp Frank wrote:
On Wed, Feb 10, 2021 at 02:38 AM, greenboxmaven wrote:

I have restored some Sony video recorders that were loaded with the bad
condensers.
The affected Tek 'scopes use multilayer boards, making a slightly more intricate procedure advisable.

Raymond


























Re: Tek 576 - step generator power amp - how to check?

Chuck Harris <cfharris@...>
 

Disgruntled? No, that wasn't it.

Tekscopes was once a fun group that mingled technical discussions
with topical things that happened to strike any member's fancy...
much like it is today, only now maybe to a slightly lesser degree.

The group's owner was away, busy doing other things, including
cultivating a business selling his own brand of snake oil to
audiophools.

Tekscopes was pretty free-wheeling.

There were always members then, as there are members now, that simply
despise any talk of things not tektronix.... Well, unless they are
the ones doing the off topic talking, of course. There were even a
fun few that liked tube scopes, but hated discussion about solid state
scopes... and vice versa, I would suppose...

One pretty day, a thread started that was making fun of audiophoolery,
and one of the self appointed moderators woke the group's owner from
his multiyear slumber, and seeing his market being ridiculed, he took
action.

All told, some 2 dozen members were banned from the group, and
probably an equal number left in support of those banned, myself
included. Many of the banned members were not even involved in the
thread, and many who were involved, weren't banned, leading some to
surmise that some grudges were being settled that day.

We formed tekscopes2 as an alternative to tekscopes, and formally
allowed technical discussions to mingle with off topic discussions.
Our only prohibition was mean behavior, and spamming. Kuba Ober
took the helm initially, and David Partridge took over from him.

When tekscopes's owner got a paying gig with tektronix, running their
blog/user's group, he lost all interest in tekscopes, and accepted
Dennis Tillman's kind offer to take over the day-to-day running
of the group...

Dennis occasionally allows the off-topic chit chat... Hell, he even
starts off topic chit chat... and rules with a wise gentle hand.

His better understanding of the group's dynamics encouraged many
tekscopes2 members (those who hadn't yet died) to come back to
tekscopes.

And, that is where things stand today.

-Chuck Harris, Charter member of tekscopes2

Dave Daniel wrote:

The TekScopes2 group was purportedly started by some TekScopes members who became
disgruntled about something to do with the TekScopes forum. I don't know what
precisely the issue was - it was before I joined either group.

DaveD


On 2/10/2021 4:10 PM, Ozan wrote:
I'll make a copy in the "...2"  group.
I meant in the "..." without "2" group... its done.

Here it is: https://groups.io/g/TekScopes/album?id=260560
After seeing the pictures I want my own 576.

What is the difference between TekScopes and TekScopes2 groups?

Ozan





Re: Dark deposit on pins near leaking SMD electrolytic caps

Jim Ford
 

Interesting! Yes, I would expect an asymmetric board to have warpage issues if it were large compared to its thickness. That extends to very small but very thin boards as well, as I know from experience. When I worked for Broadcom, one time we had 8 mil thick boards fabbed about the size of small postage stamps, IIRC. Yep, they curled up like potato chips and were useless! Something about dummy boards going into test sockets, I think, so we weren't really hampered by the failure.

Thanks, Chuck.

Jim

------ Original Message ------
From: "Chuck Harris" <cfharris@erols.com>
To: TekScopes@groups.io
Sent: 2/10/2021 7:57:11 AM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

Back when 2 layer boards were not quite good enough, and 4 layer
boards attached a pretty hefty premium, some, including myself,
made 3 layer boards.

A 4 layer board can be made in a couple of different ways:

1) SS bonded to DS bonded to SS
2) DS bonded to blank bonded to DS

In either case , there are 3 fiberglass layers, and 4 metal layers.

A 3 layer board is made by a SS bonded to a DS.

The 3 layer board has only 2 fiberglass layers, and 3 metal layers.

They work well when the boards are small, but larger sized boards
are bound to be warped from the start.

Other than cost, 3 layer boards work well with TTL circuitry, as
you typically use the middle layer as a ground plane, and salt little
ceramic capacitors to every chip's VCC pin.

-Chuck Harris

Jim Ford wrote:
OK. I will change my story to I've never seen 3-layer boards.

Usually when I see something that doesn't make sense, I attribute it to "It must have
been less expensive to do it that way."

Thanks, Harvey.

Jim

------ Original Message ------
From: "Harvey White" <madyn@dragonworks.info>
To: TekScopes@groups.io
Sent: 2/9/2021 8:53:30 PM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

Physically, one layer, copper on top.

inner layer (* see note)

outer layer, copper on bottom.

That inner layer can be single sided or two sided, depending. I don't think that
anything in the manufacturing process keeps it from being so. I've actually made 3
layer boards, although they're quite awkward without plated through holes.

One side of that inner layer can be missing, so yes, a 3 layer board. I guess it
was cheaper to make for some reason, but that was then, long ago (in electron
lives) then...

Harvey


On 2/9/2021 11:33 PM, Jim Ford wrote:
3-layer boards? Never heard of them. Maybe you mean 3 dielectric layers and 4
metal layers? PCBs are built up from the inside out, starting with a core (fully
cured dielectric sheet plated on both sides with copper foil) and adding more
cores and/or prepregs (partially cured dielectric sheet plated on one side with
copper) symmetrically on both sides until the stackup is done. Hence there is
always an even number of (metal) layers. Always!

Jim Ford

------ Original Message ------
From: "greenboxmaven via groups.io" <ka2ivy=verizon.net@groups.io>
To: TekScopes@groups.io
Sent: 2/9/2021 6:02:16 PM
Subject: Re: [TekScopes] Dark deposit on pins near leaking SMD electrolytic caps

The Sonys have three layer boards, I didn't have any problems. However, I can
imagine some very bad problems if the electrolyte got into a connection that
connects with one of the inner layers. How would you deal with that?

Bruce Gentry, KA2IVY


On 2/9/21 20:44, Raymond Domp Frank wrote:
On Wed, Feb 10, 2021 at 02:38 AM, greenboxmaven wrote:

I have restored some Sony video recorders that were loaded with the bad
condensers.
The affected Tek 'scopes use multilayer boards, making a slightly more intricate
procedure advisable.

Raymond


























Re: Maybe OT? TELEQUIPMENT CT71

Stephen
 

On Wed, Feb 10, 2021 at 11:32 AM, Dave Voorhis wrote:


On 10 Feb 2021, at 21:54, Stephen <stephen.nabet@gmail.com> wrote:


What do you guys think of this curve tracer compared to other “real” Tek
ones?
What would it compare to in the official Tek line? Is it worth it?
I’ve never used a curve tracer before, and I don’t own one, I’m just
curious.

I have one.

It has neither the range of features or the industrial build quality (or the
storage capability) of my Tek 577 D1, but it’s still a nice, capable curve
tracer.

On the plus side, it has an illuminated graticule, which my 577 doesn’t
have.

Storage?
What kind of features would you say it’s lacking?
Build quality isn’t good? From the pictures it looks like any other good Tek gear to me.


Re: Maybe OT? TELEQUIPMENT CT71

Dave Voorhis
 

On 10 Feb 2021, at 21:54, Stephen <stephen.nabet@gmail.com> wrote:


What do you guys think of this curve tracer compared to other “real” Tek ones?
What would it compare to in the official Tek line? Is it worth it?
I’ve never used a curve tracer before, and I don’t own one, I’m just curious.
I have one.

It has neither the range of features or the industrial build quality (or the storage capability) of my Tek 577 D1, but it’s still a nice, capable curve tracer.

On the plus side, it has an illuminated graticule, which my 577 doesn’t have.


Re: CSA, UL/ULC and CE approvals for Tek gear

John Williams
 

Jon:

I guess I am just dumb, but I fail to see what the problem is here. In the United States electrical equipment needed UL approval to be sold in that country. Same in Canada with CSA approval. These standards did not come from lawyers and politicians, but from safety experts and engineers. They were needed to protect consumers from shoddy products that endanger people’s lives. Certainly you wouldn’t want your wife or kid to use unapproved toasters computers etc.

As far as I know all Tektronix equipment had UL approval, at least mine does. I don’t think plug-ins or other things that didn’t connect to the power line required approval. But all my powered equipment has.

And as far as you “jest” goes I think in today’s political climate jests about killing people simply because of their chosen profession is in poor taste and inappropriate. That is just my opinion. But it is better to speak up and be thought a fool than to open one’s mouth and remove all doubt.

Stay safe.


Re: Maybe OT? TELEQUIPMENT CT71

Stephen
 

On Wed, Feb 10, 2021 at 11:04 AM, Jeff Dutky wrote:


According to the manual here
(https://w140.com/tekwiki/images/8/83/070-1075-00.pdf) "TELEQUIPMENT is a
registered trade mark of TEKTRONIX U.K. LTD." so it would seem to be as "real"
a piece of Tek equipment as there ever was.
Yes I agree with you , but according to TekWiki, Telequipment was originally a British company acquired by Tektronix. So how much was Tektronix really involved...?


Re: Maybe OT? TELEQUIPMENT CT71

Stephen
 

On Wed, Feb 10, 2021 at 11:01 AM, - wrote:


Link?
https://w140.com/tekwiki/wiki/Telequipment_CT71


Re: Maybe OT? TELEQUIPMENT CT71

 

According to the manual here (https://w140.com/tekwiki/images/8/83/070-1075-00.pdf) "TELEQUIPMENT is a registered trade mark of TEKTRONIX U.K. LTD." so it would seem to be as "real" a piece of Tek equipment as there ever was.


Re: Maybe OT? TELEQUIPMENT CT71

-
 

Link? FWIW Hameg also makes or made a scope that had a built in curve
tracer. But I don't thinkit was more than one of the basic octopus style
CTs that was added to a regular scope. I'm sure it would work but it
wouldn't be as versatile or have as many controls as a 575, 576, 577.

On Wed, Feb 10, 2021 at 4:55 PM Stephen <stephen.nabet@gmail.com> wrote:

What do you guys think of this curve tracer compared to other “real” Tek
ones?
What would it compare to in the official Tek line? Is it worth it?
I’ve never used a curve tracer before, and I don’t own one, I’m just
curious.






Re: CSA, UL/ULC and CE approvals for Tek gear

Jean-Paul
 

Mr Williams this was in jest, my point was merely to highlight that the problem is less the regulations than the politicians and lawyers that create them.


Be of good cheer!


Jon


Maybe OT? TELEQUIPMENT CT71

Stephen
 

What do you guys think of this curve tracer compared to other “real” Tek ones?
What would it compare to in the official Tek line? Is it worth it?
I’ve never used a curve tracer before, and I don’t own one, I’m just curious.


Re: 465B strange ripple

Stephen
 

On Wed, Feb 10, 2021 at 10:22 AM, satbeginner wrote:


In my 475A I was able to find what divider had the " worst" contacts, by
swapping one at the time between Ch1 and Ch2.

I also soaked them one at the time in IPA and turned both the C set screws, to
find the problematic one.

In the end, after cleaning, they were all ok, but had all dirty contacts.

As a test you could ground the output of the attenuator, just before the input
of the amplifier.

Again, one channel at the time to see what happens.

Leo
I will try that tomorrow and report back. Hopefully that’ll do the trick as far as the attenuator problem goes.
I did soak therm in IPA, but I didn’t work the set screws while in it. Maybe that’s why the results were disappointing...

I’ll try to find appropriate caps for the remaining power supply as well.

Thanks Leo.

PS: My 475A and my 465 have been need some repair for a while now. I’ll get to that someday... Hopefully soon. There’s only 24h in a day unfortunately... 😶


Re: CSA, UL/ULC and CE approvals for Tek gear

John Williams
 

I find it upsetting that very often as an issue is brought up for discussion someone chimes in with violence, murder and hate. I thought this sort of thing was going away but apparently not. If we want to see this sort of thing all I have to do is turn on CNN and watch the Capital insurrection. I for one would like to see people think what their comment is going to sound like before they post it. But that is just me. You obviously would disagree.


Re: Tek 576 - step generator power amp - how to check?

Dave Daniel
 

The TekScopes2 group was purportedly started by some TekScopes members who became disgruntled about something to do with the TekScopes forum. I don't know what precisely the issue was - it was before I joined either group.

DaveD

On 2/10/2021 4:10 PM, Ozan wrote:
I'll make a copy in the "...2" group.
I meant in the "..." without "2" group... its done.

Here it is: https://groups.io/g/TekScopes/album?id=260560
After seeing the pictures I want my own 576.

What is the difference between TekScopes and TekScopes2 groups?

Ozan



--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Re: TDS510 or TDS460A or 485 scopes as upgrade

Ozan
 

485 if still available is about 220-40USD (local pickup).
I usually wait for a unit with an issue at a lower price but the reason I get them is I like the puzzle of the debug so it may or may not work for you. I paid $60 for a unit with a power supply short, later it turned out it had dirty switches and a bad timebase capacitor.

2465b is about 600+ usd shipped (out of my budget but I may decide to spend
this money).
2467b is over 800 (honestly out of my budget)
My comment above applies, you may want to wait for the right unit these prices seem too high for just a hobby unit.


How to tell 2465b from a pimped/fake 2445b?
There was a message chain in eevblog about it (you can search "fake 2465B"). I don't remember the details.

Another question, with 2465b would it be possible to have a screenshot through
HPIB? I had a quick look at the commands and seems not.
Since there is no ADC you can't read back the signal or take a screen shot from GPIB.

Ozan


Re: 465B strange ripple

satbeginner
 

In my 475A I was able to find what divider had the " worst" contacts, by swapping one at the time between Ch1 and Ch2.

I also soaked them one at the time in IPA and turned both the C set screws, to find the problematic one.

In the end, after cleaning, they were all ok, but had all dirty contacts.

As a test you could ground the output of the attenuator, just before the input of the amplifier.

Again, one channel at the time to see what happens.

Leo

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