Date   
Re: Asset tag glue removal without damaging finish?

NigelP
 

Actually in the UK you can buy Electrolube Label remover LRM; I've used it on dozens of asset labels on Tek and HP stuff without issue and it often works better than regular electronic safety solvents.

Nigel G8AYM

Re: 2465 LVPS loading

 

Dave, Its easy to get the connectors to the power supply skewed when you put it back in the case.  They are behind a row of filter caps and, as I recall, you can install them "off center" without much resistance.  Also, it has been discussed her several times, those comb connectors that go between A1 and A2 boards of the PSU can make intermittent connection if you aren't careful about their mating.  Some owners have even forgotten to replace them when reassembling the supply.
I wish you luck.

On Monday, October 21, 2019, 11:11:31 PM CDT, DaveH52 <@DaveH52> wrote:

Where were you guys 50 years ago when I was reviving a Tek 510, and a 511A? (they've long since been replaced with a 545 and now a 465M)

So I won a rather crusty 2465 'scope at an auction, but when I plugged it in it worked!  Cursors, measurements it all worked.  So I figured I'd keep it and opened it up to clean out the dust, and clean up the front panel, and repair the fan that had fallen off (what a screwy fan arrangement).  Before I buttoned it up, I turned it on to make sure I hadn't messed anything up.  It was working just fine, even as one of the 0.068uF EMI suppression capacitors on the line side of the power supply let go of its magic smoke with a flame and a loud report.  Fortunately, there was a 68 ohm resistor that protected the line fuse.  So I removed the LVPS and replaced the burnt parts, and the other 0.068uF cap that was cracked, and managed put it back in, even though everything else was in the way.  When I turned it on it was dead.  I've only got about half of the supply outputs. The +15V, +10REF, +5V, and -5V seem to be essentially absent, +5VD is 4.5v.  So I'm currently noodling my way through the schematics, looking for something that might be common to all the errant outputs.  Dave - AC2GL

So my first question is: Do you know if this power supply can be operated without loads on the outputs or will it damage itself without some minimum current draw?  The second is, where can I find that collet thing for the fan?  And third, could you wish me luck?

Re: Tektronix 475 Oscilloscope - Help With Repair

necromancermi@...
 

Update:

I stood the scope on its back end after removing the CRT cover (to try and see the CRT neck glow) and got a trace!

The scope seemed to work normally during this time however when I laid it back down the trace seemed to fade out or lose connection.

Any guidance appreciated as the high voltage section makes me very cautious to not poke around until I’m completely familiar with this unit.

As an aside my email was flooded with responses to other posts. Is that normal for this forum? Is there a way to shut that off?

Thanks!

Re: Late 2465b A5 SMD cap replacements

 

I used solid tantalum caps on my 2465B A5.  The board had been slightly damaged by the leaking electrolyte and I had to make some repairs.  I included adding some extra pad length as part of those repairs so the solid tantalums would fit just fine.  I de-rated their voltage spec by about 3 or 4 to one.  I also sought out caps with an ESR of equal or less than the electrolytics that I used in the past for the A5.  FWIW, I see no problem with modern solid tantalum caps in light duty bypass applications if you de-rate their voltage specs by at least 2 to one.

On Monday, October 21, 2019, 09:29:18 PM CDT, Paul Amaranth <paul@...> wrote:

I'm acquiring parts to go through a 2465B and I seem to have
neglected picking up replacements for the smd caps on the A5
board.

Does anyone have sugestions for replacements?  I noticed in one
pdf floating around they were replaced with solid tantalums.  I'm
not quite sure about that.  I surely do not want to use the junk
caps I have on hand for small project work.

thanks

--
Paul Amaranth, GCIH            | Manchester MI, USA             
Aurora Group of Michigan, LLC  |  Security, Systems & Software
paul@...              |  Unix & Windows

Re: Late 2465b A5 SMD cap replacements

Chuck Harris
 

Tantalum would be ok for these capacitors, if you
can find any that will fit. The spacing of the pads
is for SMD electrolytic caps, and tantalum caps of
the same voltage and value tend to be longer.
(it has to do with the electrolytic caps sticking
up from the board...)

Also, and this is important: Electrolytic caps are
almost exclusively marked on the *negative* terminal.

Tantalum caps are almost exclusively marked on the
*positive* terminal.

Cleanup of electrolyte must be done with detergent
and water, with a good rinse. You can actually see
the electrolyte with the right wavelength UV light.

-Chuck Harris

Jean-Paul wrote:

Paul you need to research the A5 SMD cap leakage threads, and go to EEVblog.....2465b teardown (64 pages !).

The caps leak corrosive electrolyte due to poor seals, the electrolyte flows and corrodes components and traces of the PCB.

Drill....remove, clean, Replacement with electrolytic caps NOT tantalum, replacement all damaged parts.

Send a good photo of the A5 for further information.

Bon courage


Jon



Tek 2465A knobs and 6136 probe plastic connector

GerryR
 

I'm looking for a source for the small knobs that are under the CRT display (scale illum, focus, etc.). I need one, but would like to get at least one more to have as a spare. Also, looking for the plastic probe connector that holds the pin, spring and 11 K resistor for the readout scale change, Tek p/n 131-3219-00, to the compensator box. The probe I have came with a cracked one that disintegrated when I went to attach it to the scope. I did find the pin, spring and resistor (if that is all that was in there) when it parted.
Any leads appreciated.
Gerry

Re: 2465 LVPS loading

Jean-Paul
 

David the 5V needs about 30 W load, or it will not fully turn on.

See other threads here and in EEVblog for 2465 power supply dummy load construction.

Bon courage


Jon

Re: Late 2465b A5 SMD cap replacements

Jean-Paul
 

Paul you need to research the A5 SMD cap leakage threads, and go to EEVblog.....2465b teardown (64 pages !).

The caps leak corrosive electrolyte due to poor seals, the electrolyte flows and corrodes components and traces of the PCB.

Drill....remove, clean, Replacement with electrolytic caps NOT tantalum, replacement all damaged parts.

Send a good photo of the A5 for further information.

Bon courage


Jon

Re: Late 2465b A5 SMD cap replacements

 

Firstly, I offer a custom kit with ALL the EXACT component replacements, to save you the hassle of sourcing the wrong components, due to confusion, and/or lack of knowledge.
Secondly, I offer ONLY TTH replacements for the A5 SMD caps, and absolutely NOT Tantalum.
Thirdly, if you INSIST on doing the legwork yourself, I have posted a BoM in the Files section of this group (2018 July ...), to ensure that members source ONLY the CORRECT parts, and no other.

Menahem Yachad
CondorAudio

Re: Microcap12

tek_547
 

Thanx Graig, good for the dark winter evenings.
René

Re: Asset tag glue removal without damaging finish?

 

Hi Randy,

NAPTHA can be bought in hardware stores and paint stores in quart or gallon cans is ideal for removing glue and sticky residue on any surface. It does not harm the surface or the paint at all. Also, it is inexpensive. I have used it for years. This summer I removed the labels and residue from every plugin I had. It never once harmed anything and it dissolves virtually all kinds of adhesive. The only adhesive it was ineffective on was a sort of epoxy that was used to glue down metal labels that were never supposed to be removed.

To remove epoxy use XYLENE. It is sold in hardware stores and paint stores. It comes in quart or gallon cans. Xylene is the main ingredient of Goof-Off. "Xylol", and "dimethylbenzene" are other names for Xylene. Use this chemical in a well ventilated area.

Apparently Goof-Off has recently been reformulated with ACETONE instead of XYLENE according to one web page I just looked at.
BEWARE: Both XYLENE and ACETONE damage most plastics, painted surfaces, and just about everything they come in touch with. So you should restrict their use to removing epoxy as long as you don't have any surfaces that could be harmed.

GOO GONE, a citrus scented chemical, is not as strong as NAPTHA when cleaning glue and sticky residue but it smells a lot better.

Recently I became aware of MISTER CLEAN MAGIC ERASER pads. They were originally introduced as ~1 inch thick pads but now they have thinner ones that can get into tiny places. They have a very odd texture and it is hard to imagine how this stuff could clean anything since it is so soft. Those are excellent for removing pencil and pen marks on Tek panels. I think they must have an extremely fine abrasive imbedded into them that does a good job on these markings without harming anything else. You can also use it to shine up the aluminum frame of your plugins.

90% pure (or better) ISOPROPYL ALCOHOL does a good job of dissolving the ink from permanent marker pens. A small percentage of the ink will get absorbed into the anodized aluminum front panels when it is applied and that will require more than just alcohol to get rid of. I follow the alcohol with a good rubbing using the Magic Eraser pads. That combination does a good job of getting rid of about 95% of the permanent marker ink.

Dennis Tillman W7PF

-----Original Message-----
From: Randy.AB9GO
Sent: Monday, October 21, 2019 8:11 AM

Good day,

I may have missed this in a previous post, but how do you remove the left over adhesive from the old style aluminum asset tag that use the solvent to affix the tag to the equipment? Is there a method that will preserve the finish underneath? Some of the brown paper is also still hanging on.

Thanks,
Randy AB9GO.



--
Dennis Tillman W7PF
TekScopes Moderator

2465 LVPS loading

DaveH52
 

Where were you guys 50 years ago when I was reviving a Tek 510, and a 511A? (they've long since been replaced with a 545 and now a 465M)

So I won a rather crusty 2465 'scope at an auction, but when I plugged it in it worked! Cursors, measurements it all worked. So I figured I'd keep it and opened it up to clean out the dust, and clean up the front panel, and repair the fan that had fallen off (what a screwy fan arrangement). Before I buttoned it up, I turned it on to make sure I hadn't messed anything up. It was working just fine, even as one of the 0.068uF EMI suppression capacitors on the line side of the power supply let go of its magic smoke with a flame and a loud report. Fortunately, there was a 68 ohm resistor that protected the line fuse. So I removed the LVPS and replaced the burnt parts, and the other 0.068uF cap that was cracked, and managed put it back in, even though everything else was in the way. When I turned it on it was dead. I've only got about half of the supply outputs. The +15V, +10REF, +5V, and -5V seem to be essentially absent, +5VD is 4.5v. So I'm currently noodling my way through the schematics, looking for something that might be common to all the errant outputs. Dave - AC2GL

So my first question is: Do you know if this power supply can be operated without loads on the outputs or will it damage itself without some minimum current draw? The second is, where can I find that collet thing for the fan? And third, could you wish me luck?

Re: Tektronix 222 mini scope repair, looking for schematics

Henry Hopkinson
 

If the 222 TEK is the DSO 222 you can download the users manual from this
website.
bama.edebris.com/manual.
Henry

On Sun, Oct 20, 2019 at 5:43 PM ArtekManuals <manuals@...>
wrote:

Leo

We have the full service manual with schematics for the 222A which I am
told ( though I have no personal experience in using it to service a 222)
There are only minor differences between the 222 and the 222A

Contact me off list for details
Dave
manuals@...

On 10/20/2019 5:26 PM, johncharlesgord via Groups.Io wrote:
Leo,

Qservice has a pdf of the 224 manual, which includes schematics. The
224 and 222 are quite similar.

--John Gord

On Sun, Oct 20, 2019 at 01:55 PM, satbeginner wrote:

Hi all,

A friend gave me 222, because it was a Tek and he knew "I have a thing"
for
Tektronix.
It's almost mint!, But... The readout is clearly visible, but there is
no
trace?
I tried inputting a signal, but I never got the triggered light to come
on,
nor did I got something visible but the readout.

It will be another 5 days before I get home, but meanwhile I want to
think
about the problem.
I looked for a manual including the schematics, but found nothing.

After the recent submerge of the microfiche set, could they be in there?
Is there anything available?

Un saludo,

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


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




Re: Asset tag glue removal without damaging finish?

Tom Green
 

Yes, Ronsonol lighter fluid, which is just Naptha. Won't harm the finish.
You can buy a can of naptha at the hardware store. Or Ronsonol at the
supermarket (more expensive)

Acetone will craze plastic and remove paint. BEWARE!

Tom

On Mon, Oct 21, 2019 at 11:34 AM Craig Sawyers <
c.sawyers@...> wrote:

Lighter fluid. A lot less aggressive than acetone, which is generally very
unfriendly to plastics
(which is why it is the key ingredient in nail varnish remover)

Craig

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
John Griessen
Sent: 21 October 2019 16:21
To: TekScopes@groups.io
Subject: Re: [TekScopes] Asset tag glue removal without damaging finish?

On 10/21/19 10:11 AM, Randy.AB9GO wrote:
how do you remove the left
over adhesive from the old style aluminum asset tag that use the
solvent to affix the tag to the equipment?
Acetone. Test on finish paint first.

If paint is sensitive, try peeling the aluminum back, rolling it up.
Then carefully use razor
blade to
remove most of the adhesive, then brief wipes with acetone, IPA,
goo-gone, citrus cleaner.

A final polish with gel gloss (or autmotive polishing compound) can be
good.





Tektronix 475 Oscilloscope - Help With Repair

necromancermi@...
 

I recently acquired a Tektronix 475 oscilloscope.

The scope powers up but does not get a spot or trace.

I checked all the voltages at the test points with the scope powered ON . The readings were as follows:

+5 - 4.99
-8 - 7.99
+15 - 15.0
-15 - 14.99
+50 - 49.99
+110 - 111.5

Everything appears to be within tolerance.

What do I check for next? I have repaired many monitors and PCB's but this is my first attempt at scope rebuild.

As an aside - with the unit OFF the +5 and -8 test points have continuity to ground (shorted).

Any help would be greatly appreciated. :)

Re: Asset tag glue removal without damaging finish?

ken chalfant
 

Greetings,

I have had success with WD-40 and patience.

Almost every time I had got impatience and tried to use a razor blade to speed up the process I end up scratching the surface.

Alcohol works good to remove the remain WD-40 residue. Acetone has a nasty habit of harming plastics and many kinds of finished and painted surfaces.

My two cents FWIW.

Regards,

Ken

On 21Oct, 2019, at 8:42 PM, Gary Robert Bosworth <@grbosworth<mailto:@grbosworth>> wrote:

I have always used Ronsonol lighter fluid. It is harmless on most plastics
and paints.

Gary

On Mon, Oct 21, 2019, 19:37 Randy.AB9GO <@AB9GO<mailto:@AB9GO>> wrote:

Thanks for all the good ideas. I would have left the labels alone but
someone removed them before I acquired the calibrator. 😡. It is a shame
as the unit is like new otherwise and works great.

Randy AB9GO.

This message sent to you from my mobile device via speech-to-text
technology.

Re: Asset tag glue removal without damaging finish?

Gary Robert Bosworth
 

I have always used Ronsonol lighter fluid. It is harmless on most plastics
and paints.

Gary

On Mon, Oct 21, 2019, 19:37 Randy.AB9GO <@AB9GO> wrote:

Thanks for all the good ideas. I would have left the labels alone but
someone removed them before I acquired the calibrator. 😡. It is a shame
as the unit is like new otherwise and works great.

Randy AB9GO.

This message sent to you from my mobile device via speech-to-text
technology.



Re: Asset tag glue removal without damaging finish?

Randy.AB9GO
 

Thanks for all the good ideas. I would have left the labels alone but
someone removed them before I acquired the calibrator. 😡. It is a shame
as the unit is like new otherwise and works great.

Randy AB9GO.

This message sent to you from my mobile device via speech-to-text
technology.

Late 2465b A5 SMD cap replacements

Paul Amaranth
 

I'm acquiring parts to go through a 2465B and I seem to have
neglected picking up replacements for the smd caps on the A5
board.

Does anyone have sugestions for replacements? I noticed in one
pdf floating around they were replaced with solid tantalums. I'm
not quite sure about that. I surely do not want to use the junk
caps I have on hand for small project work.

thanks

--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@... | Unix & Windows

Re: [HP-Agilent-Keysight-equipment] Microcap12

Alexandre Souza
 

The creator of the program doesn't HAVE to give away his hard work.
IP is expensive. He can sell the source code for another company.
He has no why to say why or why not he does something with HIS IP
Be thankful for the fish, thats all that was given to you.

---8<---Corte aqui---8<---
http://www.tabajara-labs.blogspot.com
http://www.tabalabs.com.br
---8<---Corte aqui---8<---


Em seg, 21 de out de 2019 às 19:24, Bryce Schroeder <
@BryceSchroeder> escreveu:

I'd be aware of a bystander effect there, though. If he's getting a
lot of such email and is bothered by it, he could put a notice
notifying people of his decision (and maybe his reasons for it) on the
page. Up to him, of course, but I wouldn't worry about bothering him
based on what other people might or might not be doing, myself.

On Mon, 21 Oct 2019 at 18:05, David DiGiacomo <daviddigiacomo@...>
wrote:

Since this happened back in July, the author has no doubt already been
contacted by roughly a zillion people asking about the source code, and
probably doesn't need any more email about it...