Date   

Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Fabio Trevisan
 

Ed,
It was sort of an amateur (and anxiety driven) approach.
The fact is that I printed that sheet on my work's laser printer (on a Friday) and didn't know then if the toner would even stick to the buttons.
I didn't think then of adding any cross-hairs or other alignment aids.
I took the sheet home on the weekend and first trials worked so well and transferred so effortlessly that I kept going and found a way to align the labels I had at hand.
Sure enough, it took me some trials and some failed batches, but I wouldn't stand waiting another week to try again.
I think that printing a rectangle border of the size of the buttons would help to cut 4 flaps that would fold and match edge-with-edge, creating a small hollow box that could be put together with adhesive tape, and the button would just drop in.
It would certainly improve the process.

Rgrds,

Fabio

On Tue, Jun 19, 2018 at 09:13 am, Ed Breya wrote:


Fabio mentioned some difficulties in aligning the text onto the button faces.
How about maybe adding guidelines or some kind of extra markings around the
texts to help cut out the physical transfer pieces? If the cruciform cutouts
can be made nicely registered to the text positions, then the edges could
squared up when wrapped over the buttons, assuring proper alignment.

Ed


Re: Tektronix 453 Power Indicator Bulb needed

ROLYNN PRECHTL K7DFW
 

I get that, but the lamp is still a consumable that will wear out again.


==========================================================

A 386 lamp has a MTBF of 15,000 or 40,000 hours depending on what data sheet you look at.

How many hours do you operate your 453 in a lifetime?


Rolynn
Tek Bvtn and Sunset 1966-1971


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

JJ
 

Fabio, The white stuff is Liquitex - an acrylic paint medium used by
artists to mix colors. Comes in assorted thicknesses and finishes. I used
the medium matt finish. They all dry clear. You can also put a coat over
the transfer to seal it. Some people use Mod Podge - water based sealer.
Excellent results as well. Any art supply store will carry them. Amazon has
it. Very popular stuff!

Try it on a piece plastic to get some experience using it. You get hooked
transferring everything in sight! Have fun!

JJ

On Tuesday, June 19, 2018, Fabio Trevisan <fabio.tr3visan@...> wrote:

Hi JJ,
On the video, it really seemed easy and the result awesome.
I have some trouble to identify what was that white glue he applied.
I don't know if it's something that is common use to people who does hand
craft stuff, or if it's just a "chic" version of white glue (Vinyl Glue)
commonly used to glue wood and paper.
Does it stick well to plastics?
Bearing in mind that the buttons are non-porous plastic, and small, will
it eventually form a film that will peel off from the button's edges?
Will the film retain its transparency over time? Because it will remain
under the letters and we can't get rid of the film without removing the
letters themselves.

On Mon, Jun 18, 2018 at 05:07 pm, JJ wrote:

I've used the cold transfer method - it works a lot better than heat
transfer for transferring images. There are many youtube videos on the
method. The process can be used on just about any medium - wood, plastic,
metal:

Check out "TheCrafsman" - very cool and entertaining:
https://www.youtube.com/watch?v=h7FKdW5ndLw

Enjoy,

JJ



Re: Up to date capacitor list for Tek 2465A and 2465B scopes (2018)

Dave Voorhis
 

On 19 Jun 2018, at 15:11, M Yachad <@yachadm> wrote:

How would I define that Excel file as modifiable online by any group member, without the necessity to download it, and then upload it again?

Sort-of cloud-editable
Google Sheets (https://www.google.co.uk/sheets/about/) is fairly good for that. Overleaf (https://www.overleaf.com/) is good too, though you define tables in LaTeX rather than a spreadsheet per se. Office365 might do it too; it would directly support Excel but maybe requires a paid Office365 account?

However, these all have the limitation of requiring that you know the link in order to see the document.

Or does anyone have any better ideas?
The TekWiki wiki would be ideal, assuming would-be editors can get appropriate accounts.


Re: Up to date capacitor list for Tek 2465A and 2465B scopes (2018)

 

Men

I'll take on this project, to develop a multi-user reference parts list.

I would like to upload an Excel file, with the relevant data - my recommendations to start with (all referred parts have been tested and confirmed suitable by users who have bought my Ebay kits over the past 3 years). However I would like any interested member to be able to go in and modify that file on line, so that it is a reflection of all the members.

How would I define that Excel file as modifiable online by any group member, without the necessity to download it, and then upload it again?

Sort-of cloud-editable

Or does anyone have any better ideas?

Menahem


CRT in Tek 2235

georgeK KB1HFT <george.kavanagh@...>
 

I understand that the Tek2235 wants a 154-0861-00 CRT, which seems to be made of Unobtanium.

Are there any known substitutions?

Are there any _available_ known Substitutions?

Thanks in advance!

73

-georgeK KB1HFT


Re: 576 Curve Tracer: Trace moving off screen and jittering when pressing CAL/Zero

thespin@...
 

I removed some circuit boards to get access to the switch board. I then took a syringe with a curved tip and sucked a small amount of deoxit inside the syringe. I stuck the tip of the syringe into the back of the switch, pulled air in, and slammed down on the plunger to try and mist the deoxit into the switch as deep as I could. This worked well.


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Ed Breya
 

Fabio mentioned some difficulties in aligning the text onto the button faces. How about maybe adding guidelines or some kind of extra markings around the texts to help cut out the physical transfer pieces? If the cruciform cutouts can be made nicely registered to the text positions, then the edges could squared up when wrapped over the buttons, assuring proper alignment.

Ed


Re: Self Governance of TekScopes.

Craig Sawyers <c.sawyers@...>
 

I think if more of these old groups were still viable, there would be even fewer off-
topic conversations here.
Viva Tekscopes!
Other groups/forums that are good and very active are;

Greenkeys http://www.qth.net/mailman/listinfo/greenkeys to do with old teletypes, but with the
occasional foray into cryptographs.
UK vintage radio https://www.vintage-radio.net/forum/index.php which is absolutely ruthlessly
moderated. Off topic posts are deleted, period, and within minutes.
Golborne Vintage Radio http://golbornevintageradio.co.uk/forum/index.php self-moderated, or very light
touch moderation.
Steve Hoffman (Audiophile mastering) http://www.stevehoffman.tv/ essentially self-moderated or light
touch forums. Generally audio system related, and good natured (not a given, on the majority of audio
forums).

There are others, such as the General Radio forum, and another on slide rules, which are very quiet
indeed.


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Ed Breya
 

Jeff,

Fabio already reported how to do the mirror imaging:

"6. Printed the file to PDF, using CutePDF writer and used the "Mirrored Output" option from the Advanced -> PostScript options."

I am also interested in this process. I downloaded the free app, and it worked - it can store a scaled, mirror-image version pdf of the Word file. I also found that with digging into the deeper printer settings, you may be able to directly print mirrored and scaled - it depends on the printer, I think (mine is a Brother HL-2070). When I tried to do it this way, however, it caused a printer error - it said the margins were off-scale. It may be fixable with more setting adjustments, but I think it's easiest to just get the app, then you can make a nice pdf of what it will look like, then just print it out if OK.

Nice work, Fabio.

Ed


Re: Self Governance of TekScopes.

Daniel Koller
 

I too was going to say that Dennis' request that the "Elders" keep topics relevant is not really asking them to "moderate" so much as to quietly guide and end the thread.  It depends on your definition of 'moderate" but it seems reasonable given that Dennis is the one who can actually pull a message off the server and so squelch the conversation for good (i.e. moderate).  But the rest of us users can use self discipline to make that effort unnecessary.  
I've been really impressed by this group's ability (and that of the HP equipment group) to stay on topic and keep this group functional long after the "death of the internet as we know it" came about.  If you want proof of that, just check out rec.crafts.metalworking, which is one of the google groups that was originally a Usenet group.   There are sill interested folks there, who correspond about machining, but the group is SWAMPED by political messages and adds for various male enhancement products, and it's a real shame it's more or less gone to shit.   I think if more of these old groups were still viable, there would be even fewer off-topic conversations here.
Viva Tekscopes!
Dan----------------------------------------------------------------------------------

On Monday, June 18, 2018, 2:12:38 PM EDT, Dennis Tillman W7PF <@Dennis_Tillman_W7pF> wrote:

Hi John,
As I tried to make clear, the moderator, that's me, doesn't have the time to read every post even if I am responsible for keeping their content relevant.

I was asking for help of the "TekScopes Elders" who have been here for so long that they have an intrinsic ability to judge when something has drifted off topic and the skill to gently nudge it back to Tektronix.

Dennis Tillman W7PF


Re: Tektronix 453 Power Indicator Bulb needed

toby@...
 

On 2018-06-19 6:21 AM, Dale H. Cook wrote:
At 10:13 PM 6/18/2018, Toby wrote:

... why is there no interest in replacing the bulb with LED?
Probably because the lamps are cheap, easily available, and a lot less
work.
I get that, but the lamp is still a consumable that will wear out again.
How much extra work would a LED specifically be?

(I own a 453 fwiw)


Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
http://plymouthcolony.net/starcity/radios/index.html




Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Joseph Strickland
 

Fabio;

Is it necessary after doing the transfer to apply some coating to protect the transferred lettering? Or is the transfer of sufficient durability to not need that?

Joe


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

 

How do you get the printer to print backwards ? (or is that in the font ?)


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Fabio Trevisan
 

Hi JJ,
On the video, it really seemed easy and the result awesome.
I have some trouble to identify what was that white glue he applied.
I don't know if it's something that is common use to people who does hand craft stuff, or if it's just a "chic" version of white glue (Vinyl Glue) commonly used to glue wood and paper.
Does it stick well to plastics?
Bearing in mind that the buttons are non-porous plastic, and small, will it eventually form a film that will peel off from the button's edges?
Will the film retain its transparency over time? Because it will remain under the letters and we can't get rid of the film without removing the letters themselves.

On Mon, Jun 18, 2018 at 05:07 pm, JJ wrote:

I've used the cold transfer method - it works a lot better than heat
transfer for transferring images. There are many youtube videos on the
method. The process can be used on just about any medium - wood, plastic,
metal:

Check out "TheCrafsman" - very cool and entertaining:
https://www.youtube.com/watch?v=h7FKdW5ndLw

Enjoy,

JJ


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Harvey White
 

On Tue, 19 Jun 2018 06:37:06 -0700, you wrote:

Hi Dennis,

Thanks for the heads up.
I didn't use any protection - YET - but I was planning to spray it on with protective varnish... of the kind that designers use to protect pencil drawn sketches.
But, I`m giving second thoughts as if it will be necessary at all... I explain why...
It took me quite more than a few trials to refine the process of how to properly center the labels on the buttons, as you can imagine.
The idea to cut the labels in that cross shape, with the cuts aligned to the outer contours of each label was, ultimately, what given me good reference lines that I could center about each button's corners...
In the process, I probably have done, and rejected, about 75% of all the labels I applied.
Every time I needed to redo one, i needed to scrape off the wrongly placed label and realized they became quite strong and scratch proof.
After the first or second I tried to scrape off gently, I gave up and decided to sand them out... and even sanding them, they wouldn't go away very easily.
The blue paper (made by pulsar) is also supposed to be able to do
decals. For other kinds of decals/front panels, I have printed on a
transparency in reverse, then glued that to a panel. The body of the
transparency protects the ink/toner.

Harvey




I will leave it like that for some time and see how well they resist to time and use.

Rgrds,

Fabio

On Mon, Jun 18, 2018 at 05:38 pm, Dennis Tillman W7PF wrote:


Hi Fabio,
Very nice idea and good documentation on how to do it. You didn't say what if
anything you put over the label to protect it after you transferred it to the
button.

Dennis Tillman W7PF


Re: Tek 2445 - No Power

 

Those plastic impellers can be difficult because they get brittle with age.  Even if you glue them, the seem might be strong but the adjacent material is still brittle.  Further, the collet is made of the same plastic and becomes brittle.  I learned all this the hard way, I broke the collet on mine and feared the impeller was about to break.  So I cured it for now.

I turned down a brass fitting from my hardware store until it fit snugly into the impeller hole.  Then I bored out the center with a tapered bit and tapered grind stone.  I did all this on my drill press, no lathe.  Then I found a brass ring (actually, a pipe "olive" used in compression fittings) that just fit the impeller shaft outside diameter.  I glued these two brass parts onto the impeller shaft with epoxy.  The impeller shaft was solid once again and I had no worries about future stresses but I needed a new collet.

For the new collet I used a collect from a Dremel tool.  They come in sizes and I think I used the one for 1/16 inch shafts.  I put threads on the internal barrel of the Dremel tool (4-40 as I recall) and used a screw (4-40) with nut to draw the collet into the rebuilt impeller.

The Dremel collet is a little "fiddly" to get lined up axially but it holds tight and works well.  The home made barrel works better than the original.  I no longer worry about breaking something when I work on the motor.

On ‎Tuesday‎, ‎June‎ ‎19‎, ‎2018‎ ‎08‎:‎45‎:‎51‎ ‎AM‎ ‎CDT, ElectroKid via Groups.Io <liv_electro=yahoo.com@groups.io> wrote:

[Edited Message Follows]

Success!
Harvey White and machineguy59 - thank you so much for your prompt and insightful replies.

It was a transistor Q1062 that went bad (Base to Emitter open circuit failure) as R1071 was getting hot from over current (inverter drive circuit).
Replaced it and the squeaky "tick mode" came back. At first I had the original C1072 (3.3u/100v) replaced, although it had good capacitance and ESR (~3.2R) with an inferior chinese temporary replacement cap which blown after 10 sec...
So I reverted back to the original Nichicon (34 years!). Q1062 is a NPN transistor PN:151-0302-00 and the equivalent I used is 2N2222.
It's the 1st time I see this 2445 beautiful display and is so clear and steady and no faults/error codes displayed, nice readout clarity! what a joy resurrecting it!

After all that, I had another small but important issue: No Cooling
Fan not spinning, I measured supply 24V instead of 19.2V (15V unregulated) - I wondered is it too high??...
The fan doesn't spin, it's held in place by very strong magnetic force induced, at one time it did move a bit upon power up and stopped firmly,
only when unit powered down I can rotate the spindle easily with my fingers so I was thinking/testing:
Could the hall effect motor that this 2445 uses be faulty?
Could it be the fan board is getting to much voltage to make it stuck so hard?
I put 330uF/50V for C1116 at the rectifier section, could it be too much capacitance? (original is 180uF...)
The fan is temperature controlled and should be constantly spinning right? Or is the temp sensor that kicks in when temp is high and releases the motor shaft
The temp sense RT1696 reads 4.15Kohm at cold state and goes down to 1K after 15sec from power on, or from 24V to 7V. When does it kick in and moves the motor?
Finally - discovered U1690 IC (Quad transistor) which drives the motor 4 windings, had a faulty transistor: shorted Collector to Emitter (4 ohm) !
Under this IC pcb shows quite a blackening and probably suffered alot of heat trying to move a stuck motor.
This was probably one of the causes that made the faulty inverter capacitors fail from high temps over time (no air flow)...
Fortunately, the motor is still good and spins freely, all I did is replace U1690 (MPQ3725) with 4x 2N2222 transistors as suggested by Kibi on EEvblog:
https://www.eevblog.com/forum/repair/tektronix-2445-repair/   {-thanks}
The temperature resistor also reacts nicely to temp changes and controls fan speed.

Now I'm waiting for a full cure of the squirrel-fan collet I glued together as I broke it, I hope it will work fine and hang nicely on to the motor shaft.

Thanks again guys.


Re: Up to date capacitor list for Tek 2465A and 2465B scopes (2018)

Brian Cockburn
 

Michael,

That sounds like a great idea. Is it reasonable to assume that a given part, like a 47uF 35V electrolytic, would have a single modern replacement recommendation? Or would it perhaps be necessary to use the Tek part number as the 'index' into the set of new part pages?

Either way, there could be a wiki page for each part, with notes associated with it like the ref-des for various models and any gotchas.
Then each model could have a list, by ref-des, of the parts that are candidates for replacement, with each line then clicking-through to the part page. The lists could perhaps even be partitioned into obvious areas like SMPS, PS, Vert, Trig, TB, etc. The only downside to this (general wiki pages) would be that it wouldn't be simple to get a BoM for the replacements for a model. That sort of stuff requires a more data base like back end I expect.

Cheers, Brian.


Re: Tek 2445 - No Power

ElectroKid
 
Edited

Success!
Harvey White and machineguy59 - thank you so much for your prompt and insightful replies.

It was a transistor Q1062 that went bad (Base to Emitter open circuit failure) as R1071 was getting hot from over current (inverter drive circuit).
Replaced it and the squeaky "tick mode" came back. At first I had the original C1072 (3.3u/100v) replaced, although it had good capacitance and ESR (~3.2R) with an inferior chinese temporary replacement cap which blown after 10 sec...
So I reverted back to the original Nichicon (34 years!). Q1062 is a NPN transistor PN:151-0302-00 and the equivalent I used is 2N2222.
It's the 1st time I see this 2445 beautiful display and is so clear and steady and no faults/error codes displayed, nice readout clarity! what a joy resurrecting it!

After all that, I had another small but important issue: No Cooling
Fan not spinning, I measured supply 24V instead of 19.2V (15V unregulated) - I wondered is it too high??...
The fan doesn't spin, it's held in place by very strong magnetic force induced, at one time it did move a bit upon power up and stopped firmly,
only when unit powered down I can rotate the spindle easily with my fingers so I was thinking/testing:
Could the hall effect motor that this 2445 uses be faulty?
Could it be the fan board is getting to much voltage to make it stuck so hard?
I put 330uF/50V for C1116 at the rectifier section, could it be too much capacitance? (original is 180uF...)
The fan is temperature controlled and should be constantly spinning right? Or is the temp sensor that kicks in when temp is high and releases the motor shaft
The temp sense RT1696 reads 4.15Kohm at cold state and goes down to 1K after 15sec from power on, or from 24V to 7V. When does it kick in and moves the motor?
Finally - discovered U1690 IC (Quad transistor) which drives the motor 4 windings, had a faulty transistor: shorted Collector to Emitter (4 ohm) !
Under this IC pcb shows quite a blackening and probably suffered alot of heat trying to move a stuck motor.
This was probably one of the causes that made the faulty inverter capacitors fail from high temps over time (no air flow)...
Fortunately, the motor is still good and spins freely, all I did is replace U1690 (MPQ3725) with 4x 2N2222 transistors as suggested by Kibi on EEvblog:
https://www.eevblog.com/forum/repair/tektronix-2445-repair/ {-thanks}
The temperature resistor also reacts nicely to temp changes and controls fan speed.

Now I'm waiting for a full cure of the squirrel-fan collet I glued together as I broke it, I hope it will work fine and hang nicely on to the motor shaft.

Thanks again guys.


Re: Tek push-button lettering using pressing iron transfer of laser printed text on non-sticking paper

Fabio Trevisan
 

Hi Dennis,

Thanks for the heads up.
I didn't use any protection - YET - but I was planning to spray it on with protective varnish... of the kind that designers use to protect pencil drawn sketches.
But, I`m giving second thoughts as if it will be necessary at all... I explain why...
It took me quite more than a few trials to refine the process of how to properly center the labels on the buttons, as you can imagine.
The idea to cut the labels in that cross shape, with the cuts aligned to the outer contours of each label was, ultimately, what given me good reference lines that I could center about each button's corners...
In the process, I probably have done, and rejected, about 75% of all the labels I applied.
Every time I needed to redo one, i needed to scrape off the wrongly placed label and realized they became quite strong and scratch proof.
After the first or second I tried to scrape off gently, I gave up and decided to sand them out... and even sanding them, they wouldn't go away very easily.

I will leave it like that for some time and see how well they resist to time and use.

Rgrds,

Fabio

On Mon, Jun 18, 2018 at 05:38 pm, Dennis Tillman W7PF wrote:


Hi Fabio,
Very nice idea and good documentation on how to do it. You didn't say what if
anything you put over the label to protect it after you transferred it to the
button.

Dennis Tillman W7PF