Date   

Re: Looking for a Tek 5030 or R5030 scope

David DiGiacomo
 

Too bad you missed this one: http://www.ebay.com/itm/182656200183


Re: 2465A Cap replacements

 

The files at TekScopeArc will work for the power supply (A2 and A3 I believe).  The board with surface mount caps is the A5 board in some generations of the 2465B.  My 2465A has no surface mount caps.  I doubt that yours does either.  The 2465A A5 board uses five 47 mfd 25 Volt caps (I used 35 Volt versions).
Take note on recapping the A3 board (part of the low voltage poser supply module).  All Tek documentation for board layout has C1115 and c1132 swapped in position.  Specifically, the board layout in the schematic shows C1115 where C1132 should be and C1132 where C1115 should be.  C1132 is exposed to 97 volts and will immediately fail a low voltage capacitor such as C1115.  So either check by noticing what you remove or by checking connection to related parts.  I double check my work by verifying that the positive terminal of 250 Mfd 35 Volt C1115 directly connects to L1115.      

From: "spikeiskewl@yahoo.com [TekScopes]" <TekScopes@yahoogroups.com>
To: TekScopes@yahoogroups.com
Sent: Tuesday, August 15, 2017 4:13 PM
Subject: [TekScopes] Re: 2465A Cap replacements

  I found some of the files over in the TekScopeArc.
I'll see if I can find the other TekScopeArc 2 or something?

cheers,



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[Non-text portions of this message have been removed]


Re: 2465A Cap replacements

Spike
 

I found some of the files over in the TekScopeArc.
I'll see if I can find the other TekScopeArc 2 or something?

cheers,


2465A Cap replacements

Spike
 

Hi,

Before I start to replace these, I need to find the file that has which are the
caps to replace and on which boards.

I have an 2465A, and I understand the difference with the 2465B is
the latter has the SMDs on one of the boards?


I'll look around for the battery replacement check while I'm at it.


Re: Looking for a Tek 5030 or R5030 scope

John Griessen
 

On 08/15/2017 10:20 AM, walter2@sphere.bc.ca [TekScopes] wrote:
R5030 for $600 on ebay, but too much for me, I was hoping for something a bit better.
Yes, the last hamfest I went to in Belton TX they were $10 in that condition.
Not seen lately though.


Re: 575 Mod122C with keys. SN005100

David Holland
 

There's a couple of paper capacitors in the HV supply. I'd be more likely
to suspect them than the transistors.

Everyone I've repaired (a whopping two) has came up just fine once I got
done recapping it (except the one that had a busted CRT, it needed a new
one of those too..... :-) )

David


On Tue, Aug 15, 2017 at 2:55 PM, 'Craig Sawyers'
c.sawyers@tech-enterprise.com [TekScopes] <TekScopes@yahoogroups.com> wrote:

Anyway I have now turned it on - probably the 1st time in 10 years from
the internal grot - and
although there is no trace the LV supplies are spot on.
There is a germanium power transistor in there that can sometimes be
rather flakey. Something to do
with collector control if I remember correctly.

You could test it with a curve tracer (ha ha)

Craig




------------------------------------
Posted by: "Craig Sawyers" <c.sawyers@tech-enterprise.com>
------------------------------------


------------------------------------

Yahoo Groups Links




Re: 575 Mod122C with keys. SN005100

Christopher Hilton-Johnson
 

Dennis

As to the photos, you are correct as ever - & if I can work out how to
do that easily I will upload some photos (why yahoo will not allow
photos to accompany posts I will never understand)

That it was adapted for the educational market was my 1st thought, also
from the safety point of view. Easily accessable big volts not good if
students can get close to them!

I need to get it clean & working before I can understand the extra key
operated on/off switch (it certainly does not turn either the LV or EHT
supplies off)

Will continue a bit of fettling over the next week or so & let the group
know if I find anything useful

Christopher

On 15/08/2017 05:04, 'Dennis Tillman' dennis@ridesoft.com [TekScopes] wrote:

Hi Christopher,
Back in the day 400V collector voltages were not common and those
voltages were present on banana plugs that were easy to touch. I
suspect this was a modification that made a lot of sense in certain
settings such as a technical college or training facility.

I have never heard of this being done before but the Mod 122C was not
so common that I have seen a lot of them. It sounds like it was done
quite well so perhaps it was a factory modification. If it was made
for the European market this key lock would make more sense because
Europe is much more safety conscious about voltage since they use 220
which is far more dangerous than the 110V used in the USA.

A picture is worth a thousand words. It would be nice to see a picture
of the front panel.

Dennis Tillman W7PF

-----Original Message-----
Sent: Sunday, August 13, 2017 12:07 PM
Subject: [TekScopes] 575 Mod122C with keys. SN005100

Recently acquired one of these.

It has a 3 position key operated lock in place of the knob used for the
3 position Peak Volts Range

and an additional 2 position key operated lock mounted in the bottom
left hand corner of the front fascia. The key positions are marked "Off"
and "On"

The same key operates both locks. The key is locked in its lock except
where (in the Peak Volts Lock) the 0-20 position is selected and (in
the lower left lock) the 'Off" position is selected.

Each lock is marked with either 3 ( Peak Volts Lock) or 2 (lower left
lock) red coloured intented dots, corresponding to the possible key
positions.

The whole looks either original or a professionally added modification

The accompanying manual is silent. To my limited knowledge it did not
come from an educational establishment.

any ideas before I turn it on? Anyone seen something similar?

crippo2
------------------------------------
Posted by: Christopher Hilton-Johnson <chj@pchjhome.com>
------------------------------------


Re: 575 Mod122C with keys. SN005100

Craig Sawyers <c.sawyers@...>
 

Anyway I have now turned it on - probably the 1st time in 10 years from the internal grot - and
although there is no trace the LV supplies are spot on.
There is a germanium power transistor in there that can sometimes be rather flakey. Something to do
with collector control if I remember correctly.

You could test it with a curve tracer (ha ha)

Craig


531A needs a new home

 

Hi All,

I have a 531A scope with a 53/54B plugin still in the box as it was
returned from the Tektronix cal lab back in 1976. I recently pulled the
staples out top open the box to see what was inside. I am downsizing and
this needs a new home. I would rather not try to ship it, but I will be
traveling to the Huntsville AL hamfest this weekend if anyone is interested.

Please respond privately

--
James True N5ARW
www.boatanchor.com


Re: 575 Mod122C with keys. SN005100

Christopher Hilton-Johnson
 

Craig

Yes it could be, but then I would have hoped some accompanying paperwork
might have given a clue.

Anyway I have now turned it on - probably the 1st time in 10 years from
the internal grot - and although there is no trace the LV supplies are
spot on.

If I can remember how to post a photo in the archive I wIll upload a few

Good to be back on the forum after several years as just a lurker!

Christopher


On 14/08/2017 07:35, 'Craig Sawyers' c.sawyers@tech-enterprise.com
[TekScopes] wrote:

Christopher: Could it be a Tek-supplied custom modification for a
specific customer?

Craig

It has a 3 position key operated lock in place of the knob used for the
3 position Peak Volts Range

and an additional 2 position key operated lock mounted in the bottom
left hand corner of the front
fascia. The key positions are marked "Off"
and "On"
------------------------------------
Posted by: Christopher Hilton-Johnson <chj@pchjhome.com>
------------------------------------


[Non-text portions of this message have been removed]


Re: Overkill use for fast scope

cmjones01
 

On 14 Aug 2017 9:56 p.m., "very_fuzzy_logic@yahoo.com [TekScopes]" <
TekScopes@yahoogroups.com> wrote:



Maybe you should be concerned if you suddenly get requests from Pyongyang
for help with fixing garage doors!


I shall remain vigilant and not let my advanced garage door repair
technology fall into the wrong hands!


Sorry but I should have replied earlier when you posted your results on
risetime measurements with the 7A29. It must have been me who pipped you on
the7A29P! I measured only a small reduction, from 700psec with a 7A19 to
600-650psec with the 7A29P.


That's interesting. I'm glad to know the 7A29P went to a good home. There
can't be that many of us with an application for one.

I'm not having much luck with eBay recently. I had my heart set on a 7904A
in the UK with an appealing set of plugins, but someone else bought it
while I was confirming some details with the seller. I'm sure another one
will be along in 5 years or so :-/

Chris


re-making pushbuttons

 

in several groups, the problems of the ink markings coming off pushbuttons has been a recurring theme. Tek buttons and rotary knob skits are especially easy to remove the markings (windex can usually do it), and very frustrating when blank.


the whole concept of pad marking buttons is a very low quality technique, and really not suitable for long term use. keyboard makers have known this for decades, and use a two-shot injection mold to make the character a part of the button itself.


you can restore any blank button easy simply by cleaning the surface, then engrave the desired legend, and back fill with black paint, it is pretty much indestructible at that point.



before you say "I have no way to engrave it", most jewelers, or trophy awards places have an engraving pantograph and do it cheaply and quickly for very little money. we used to have one in our shop, and used it for panel markings and similar stuff all the time. they show up on ebay, and you can actually make one easily with a small dremel tool, just search youtube for examples.


all the best,
walter
sphere research corp.


Looking for a Tek 5030 or R5030 scope

 

Does anybody have one to sell or trade? I am interested in the look and functionality of this unit, but haven't seen one for a long time. there is a rough unknown condition R5030 for $600 on ebay, but too much for me, I was hoping for something a bit better. the 5030 would be perfect, not sure the storage 5031/R5031 would be easy to keep running at this point, but maybe an alternative.

any leads appreciated. this is such nice looking unit with a BIG CRT, and ideal for low level audio work, so it's right up my alley.

all the best,
walter (walter2 -at- sphere.bc.ca)
sphere research corp.


Re: OT: CRT Yokes/ferrite

mosaicmerc
 

Good news.
I pulled the yoke ferrite from a 12 year old CRT 14" monitor.
Averaged the dimensions, knowing turns and inductance, to calculate the permeability as a toroid and it came out to about 800.
AL of 730 .
That looks exactly like a large ferrite mix 43.
Precisely the recommended mix for the output impedance transformer!

Still might have to locate some low DF , hi Q 600V+ caps for the output tuning (2 to 4nF).

Interestingly, I measured 12 cm x 9 cm piece of double sided 1oz copper flex PCB and it is 5nF but the Q is 'only' 70 at 100Khz. The dielectric is good to several KV though.
Might be worth a try as I only need to run the amp for a few minutes at a time. Will probably have to cut it into a disc and dip it in fibre glass resin.

Tried some copper foil 'tape' with kapton tape dielectric and the Q was even less.
I have some 0.5 mil Mylar dielectric to try out and see. I've only tested the mylar to 170Vpp (mains) as transistor insulators with hi thermal performance as they're so thin.

A silver mica 3.3nF cap (1KV) has upwards of 2000 Q.


The CRT flyback ferrite looks a bit smaller than the one I got from the laser cutter PSU. Haven't desoldered it yet to check its permeability, we'll see if it's similar to the mix 31 as in the laser ferrite.


Re: KO4BB Manual Pages

Glydeck
 

Didier,

Thank you! Your site has always been an amazing resource.

Glydeck KD6NEW
Sent from my iPad

On Aug 14, 2017, at 8:55 PM, 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> wrote:

Hi Didier,
Thank you for the update and for the years of unselfish support you have
provided all of us (not just Tek folks) with you wonderful website. Your
contribution makes it possible for me personally to have a wonderful lab
full of test equipment.

And a special thank you for the Thunderbolt monitor program you gave me many
years ago. It quickly became an integral part of my GPS Frequency Standard.
I have received many complements on your GPS monitor program.

If there is any way I can be of help to you please let me know. It's the
least I can do.

Dennis Tillman W7PF

-----Original Message-----

On 8/13/2017 2:54 PM, Didier Juges shalimr9@gmail.com [TekScopes] wrote:

News flash!

If you have been using my site to upload and download manuals, you may
have noticed that in the last year or so I had become fairly slow at
checking new uploads and moving them to the general area so that they
can be downloaded.

The reasons were multiple and I want to take this opportunity to
apologize to you. Just because this service is free is not an excuse
to make it hard to use or inconvenient.

The good news is that I do have a new tool now that allows me to check
and move the uploaded manuals to their respective folders conveniently.

More improvements are planned to the upload log (letting you know what
the file name was changed to and where it was moved), these will come
later.

This primarily applies to documents in PDF or image (GIF, JPG, PNG)
format that I can easily preview. DOC, ZIP or RAR files unfortunately
still require more manual intervention, so they will not benefit from
this improvement, but since I will spend less time processing the PDF
files, which are the vast majority of the files that are uploaded, I
will have more time available for the rest.

I remind you that files that are in the Upload folder are readily
accessible via ftp, so if you need one or more files that are in the
Upload folder and that I have not moved yet, fire up your ftp client
(info is on the Manuals page).

Thank you for your patience and patronage.

Didier KO4BB


Re: 575 Mod122C with keys. SN005100

 

Hi Christopher,
Back in the day 400V collector voltages were not common and those voltages were present on banana plugs that were easy to touch. I suspect this was a modification that made a lot of sense in certain settings such as a technical college or training facility.

I have never heard of this being done before but the Mod 122C was not so common that I have seen a lot of them. It sounds like it was done quite well so perhaps it was a factory modification. If it was made for the European market this key lock would make more sense because Europe is much more safety conscious about voltage since they use 220 which is far more dangerous than the 110V used in the USA.

A picture is worth a thousand words. It would be nice to see a picture of the front panel.

Dennis Tillman W7PF

-----Original Message-----
Sent: Sunday, August 13, 2017 12:07 PM
Subject: [TekScopes] 575 Mod122C with keys. SN005100

Recently acquired one of these.

It has a 3 position key operated lock in place of the knob used for the
3 position Peak Volts Range

and an additional 2 position key operated lock mounted in the bottom left hand corner of the front fascia. The key positions are marked "Off"
and "On"

The same key operates both locks. The key is locked in its lock except where (in the Peak Volts Lock) the 0-20 position is selected and (in the lower left lock) the 'Off" position is selected.

Each lock is marked with either 3 ( Peak Volts Lock) or 2 (lower left
lock) red coloured intented dots, corresponding to the possible key positions.

The whole looks either original or a professionally added modification

The accompanying manual is silent. To my limited knowledge it did not come from an educational establishment.

any ideas before I turn it on? Anyone seen something similar?

crippo2
------------------------------------
Posted by: Christopher Hilton-Johnson <chj@pchjhome.com>
------------------------------------


Re: KO4BB Manual Pages

 

Hi Didier,
Thank you for the update and for the years of unselfish support you have
provided all of us (not just Tek folks) with you wonderful website. Your
contribution makes it possible for me personally to have a wonderful lab
full of test equipment.

And a special thank you for the Thunderbolt monitor program you gave me many
years ago. It quickly became an integral part of my GPS Frequency Standard.
I have received many complements on your GPS monitor program.

If there is any way I can be of help to you please let me know. It's the
least I can do.

Dennis Tillman W7PF

-----Original Message-----

On 8/13/2017 2:54 PM, Didier Juges shalimr9@gmail.com [TekScopes] wrote:

News flash!

If you have been using my site to upload and download manuals, you may
have noticed that in the last year or so I had become fairly slow at
checking new uploads and moving them to the general area so that they
can be downloaded.

The reasons were multiple and I want to take this opportunity to
apologize to you. Just because this service is free is not an excuse
to make it hard to use or inconvenient.

The good news is that I do have a new tool now that allows me to check
and move the uploaded manuals to their respective folders conveniently.

More improvements are planned to the upload log (letting you know what
the file name was changed to and where it was moved), these will come
later.

This primarily applies to documents in PDF or image (GIF, JPG, PNG)
format that I can easily preview. DOC, ZIP or RAR files unfortunately
still require more manual intervention, so they will not benefit from
this improvement, but since I will spend less time processing the PDF
files, which are the vast majority of the files that are uploaded, I
will have more time available for the rest.

I remind you that files that are in the Upload folder are readily
accessible via ftp, so if you need one or more files that are in the
Upload folder and that I have not moved yet, fire up your ftp client
(info is on the Manuals page).

Thank you for your patience and patronage.

Didier KO4BB


Re: KO4BB Manual Pages

Tom Jobe <tomjobe@...>
 

Thank you Didier!
Your site has been a great source of manuals for many years!
It is very easy to upload and download files on your site.
tom jobe...

On 8/13/2017 2:54 PM, Didier Juges shalimr9@gmail.com [TekScopes] wrote:

News flash!

If you have been using my site to upload and download manuals, you may
have
noticed that in the last year or so I had become fairly slow at checking
new uploads and moving them to the general area so that they can be
downloaded.

The reasons were multiple and I want to take this opportunity to apologize
to you. Just because this service is free is not an excuse to make it hard
to use or inconvenient.

The good news is that I do have a new tool now that allows me to check and
move the uploaded manuals to their respective folders conveniently.

More improvements are planned to the upload log (letting you know what the
file name was changed to and where it was moved), these will come later.

This primarily applies to documents in PDF or image (GIF, JPG, PNG) format
that I can easily preview. DOC, ZIP or RAR files unfortunately still
require more manual intervention, so they will not benefit from this
improvement, but since I will spend less time processing the PDF files,
which are the vast majority of the files that are uploaded, I will have
more time available for the rest.

I remind you that files that are in the Upload folder are readily
accessible via ftp, so if you need one or more files that are in the
Upload
folder and that I have not moved yet, fire up your ftp client (info is on
the Manuals page).

Thank you for your patience and patronage.

Didier KO4BB

[Non-text portions of this message have been removed]



[Non-text portions of this message have been removed]


Re: KO4BB Manual Pages

Ken Burchfield
 

Thanks for the update,
Appreciate your site and your dedication for a source for data.


73,
Ken.......k5jxl



---In TekScopes@yahoogroups.com, <shalimr9@...> wrote :

News flash!

If you have been using my site to upload and download manuals, you may have
noticed that in the last year or so I had become fairly slow at checking
new uploads and moving them to the general area so that they can be
downloaded.

The reasons were multiple and I want to take this opportunity to apologize
to you. Just because this service is free is not an excuse to make it hard
to use or inconvenient.

The good news is that I do have a new tool now that allows me to check and
move the uploaded manuals to their respective folders conveniently.

More improvements are planned to the upload log (letting you know what the
file name was changed to and where it was moved), these will come later.

This primarily applies to documents in PDF or image (GIF, JPG, PNG) format
that I can easily preview. DOC, ZIP or RAR files unfortunately still
require more manual intervention, so they will not benefit from this
improvement, but since I will spend less time processing the PDF files,
which are the vast majority of the files that are uploaded, I will have
more time available for the rest.

I remind you that files that are in the Upload folder are readily
accessible via ftp, so if you need one or more files that are in the Upload
folder and that I have not moved yet, fire up your ftp client (info is on
the Manuals page).

Thank you for your patience and patronage.

Didier KO4BB


Re: Why all the trouble with A & B Sweep mechanic interlocks

Fabio Trevisan
 

Hi David,

First of all, thanks for your reply and apologies for taking so long to
give a feedback.
to your points (between quotes, in Italics).
While examining more carefully the mechanics, I think I misinterpreted part
of what I was thinking had also an interlock (at the begging of the dial)
and I could understand why the other interlock (at the end of the dial).

*"Part of it is that to save space on the front panel, it makes sense*
*for the two sweep controls to be concentric since they share almost*
*all of the same legends"*

Fully agree, Many scopes from several brands have concentric A &B sweep
knobs...
Still they could be concentric while being independently actuated (in many
designs, a lower wider knob and a higher, thinner knob)



*"Beyond that, it does not make any sense for the B sweep to be slowerthan
the A sweep and interlock between the controls prevents this"*
Agree again, one of the features (not the only one) of the mechanical locks
between the upper (gray knob) and the lower (transparent dial) is a fixed
protruding pin that prevents the B sweep's gray knob to be turned more
counter-clock wise than the A sweep's transparent dial.
Still, that "stopper" pin could be the ONLY mechanical restraint acting
between both knobs...but no... there is the other one (which is the one I
think is awkward).



*"Maybe you are referring to the 485 timebase which operates in a wayvery
similar to the 7B92A timebase?"*
Not really, I`m not familiar with the 485, although I had a look at its
picture on TekWiki and it seems it operates (at least mechanically)
similarly as the 465 / 464 / 466 and 475 (only that the interlock range on
the 485 encompasses the 3 last sweep speeds, while the interlocks of the
46x and 475 are only for the last 2).

In either case, there's a marking "A only when knobs locked"...

I`m not sure if the 485 has a an electrical justification for that, but for
the 465, and the 464 I own, it simply isn't true.
Even when both knobs are locked (although I agree, useless), BOTH timebases
are still operational and available (not only A as the markings suggest).
You can even delay only trigger the B sweep or Trigger after delay
(although I`m not sure the DTP markings / measurements can be trusted....
Maybe that's the reason?)
The markings and the B sweep's restrained "PULL" action over the last 2
ranges, also suggest that, once the B sweep would be on either of the 2
last ranges, the A sweep would forcibly need to be: 1.) locked to the B
sweep (and therefore there would be only A sweep), or 2.) to be at 0.2us or
SLOWER.
Neither actually is true.

The locking mechanism indeed prevents you from unlocking B from A, if the
knobs are already locked and on either of the 2 last ranges... BUT.
If you unlock them at any other range, you can move B, say, to the last
range, and then move the A sweep to the 2nd last range (which the markings
imply is not valid, or not existent, but are), up to the point that, if you
advance the A timebase further (to the last range), both sweeps become
locked again and can only be unlocked while moving the knobs away from the
last 2 ranges.

The explanation I found, to this construction is only one...
They wanted to allow the operator to change the A sweep's setting by
turning one single knob, the B sweep knob (one made larger and with a firm
grip) and for some reason, they didn't want to make the 2 knobs, each at a
different level, and each with is own grip.
Maybe to save space on the panel, for the fingers to grab and move around a
wider, closer to the panel knob.

They came up then with this knob, that would allow you to position the A
sweep speed first, and then unlocking them, control the B sweep apart from
the A.
I think only later they added the awkward, tiny and rather uncomfortable
TAB, on the transparent dial of the A knob, to allow the change of A sweep
without having to lock the knobs again.
The 453 and the 454 apparently don't have the tiny tab and I suspect that,
once unlocked, if the operators needed to re-set the A sweep, they were
forced to lock the knobs again. Which was probably annoying.

Since the two concentric knobs need to be locked, in order for the operator
to gain control of the A sweep, they devised this "pull-to-unlock" spring
loaded action...
But it has some mechanical drawback...
It seems that in order for that spring-actioned unlock mechanism to work,
you need to turn the B knob apart (clockwise) at least 2 clics (in the case
of the 46x/475... not sure about the 485), before you can turn it back
(ccw) or turn the A dial forward (cw) into their locking position and the
"thing" works.

Therefore, they added the interlock (at the end of the B sweep's axle) to
prevent the operator from pulling the B knob (to unlock them) if they're at
any of the last 2 positions, in order to assure they won't jam or something
in those lines...

To remain consistent with the knob's "PULL-TO-UNLOCK" mechanical
constraints, they added the "A SWEEP ONLY WHEN KNOBS LOCKED" panel marking,
implying that deviating from that would be invalid... while the settings
"per se" are not invalid.

Well. Those at least are my conclusions, to make sense from what they
did... (It doesn't mean I concluded it right).

Still, I cannot figure out WHY... If they could have just made the TWO
KNOBS (even concentric) directly actionable by the operators (one outer
ring and one inner knob)...

Rgrds,

Fabio










2017-07-24 13:31 GMT-03:00 David davidwhess@gmail.com [TekScopes] <
TekScopes@yahoogroups.com>:



Part of it is that to save space on the front panel, it makes sense
for the two sweep controls to be concentric since they share almost
all of the same legends.

Beyond that, it does not make any sense for the B sweep to be slower
than the A sweep and interlock between the controls prevents this.

I am not sure what you mean by an interlock to prevent invalid
settings. My 22xx oscilloscopes and 7B53A timebases have no invalid
settings. The 7B92A timebase sort of does but the readout always
reflects the true configuration. On the 7B92A, this is because of its
design where the fastest sweep speeds do not actually change the sweep
and instead apply horizontal magnification. So as far as the delay
time in concerned, 10ns/div is the fastest sweep speed no matter what
while the readout and dial legend reflect the applied magnification.

Maybe you are referring to the 485 timebase which operates in a way
very similar to the 7B92A timebase? Since it lacks a readout, I
assume Tektronix might have included a lockout to prevent advancing
the A sweep beyond its actual fastest sweep speed when the B sweep is
unlocked. Note that in single sweep mode, both the 7B92A and 485
cleverly swap the A and B sweeps at the fastest sweep speeds since
only the B sweep supports them.

This led to much confusion here on the list a couple years ago when we
were trying to figure out how the 7B92A generated its fastest A sweeps
when the A sweep generator cam lacks the positions to select them.

On Mon, 24 Jul 2017 13:01:44 -0300, you wrote:

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