Date   

Re: TDS 744A - 7u01 upgrade kit ??

Mark
 

Check with the nice people at vintagetek.org. They have a lot of info on microfiche.


Re: TDS 744A - 7u01 upgrade kit ??

David Slipper
 

Thanks for that :-)

Shame the files are not available.

Dave

On 20/08/2021 20:12, zenith5106 via groups.io wrote:
On Fri, Aug 20, 2021 at 08:10 PM, David Slipper wrote:

Or perhaps its a software/fw upgrade ??
Yes firmware only.
Instructions here: http://hakanh.com/dl/docs/kitinstructions/tdsxxxU01.pdf
Since it's firmware installation had to be done by Tek and the kit was never
sold directly to customers.
/Håkan




Re: TDS 744A - 7u01 upgrade kit ??

 

On Fri, Aug 20, 2021 at 08:10 PM, David Slipper wrote:


Or perhaps its a software/fw upgrade ??
Yes firmware only.
Instructions here: http://hakanh.com/dl/docs/kitinstructions/tdsxxxU01.pdf
Since it's firmware installation had to be done by Tek and the kit was never
sold directly to customers.
/Håkan


TDS 744A - 7u01 upgrade kit ??

David Slipper
 

It looks like I need to apply this to my 744A the s/n is in the range B020xxx but I cannot find a reference to it anywhere.
Anyone know where I might find one ??
Or perhaps its a software/fw upgrade ??
Regards,
Dave


Re: Tektronix 575 122C trimmer capacitors

Keith
 

Yeah, reckon so.

The plot has thickened a little bit as I've searched even more documentation on this pesky little trimmer capacitor.

Here's the latest: Specifically, in the 1964 published version of the field version of the Mod122C, the mysterious C239 capacitor is specifically mentioned. In fact, the part is specifically INCLUDED in the field kit for Mod122C. Even more, there is a specific instruction about how and where to add the part, including a drawing of where it goes!

See for yourself: https://w140.com/tektronix_575_mod_122c_modifications.pdf

pdf pages 5, 16, 17, 21 manifest, mentions, drawings, cal procedure for the use of the part.

This seems to mean at least one thing with a fair degree of certainty. On Scopes built before 1964 and not already Mod122C, Tek was expecting at least some of the field modified 575 to be missing this part. Thus, the kit made provision to add the part. That's why it is part of the kit as issued in 1964. Remember, by 1964 the 575 was well past the "#101-4779" notation.

Bottom line: In 1964, Tek thought C239 should be there on 122ModC versions.

So,

a.) C239 - it appears it was NOT present on some (or all?) 575 versions built before 1964.
b.) It appears that by 1964 Tek specifically ADDED it for 122ModC field modifications on such scopes.
c.) One can only presume that, in Tek's opinion, it is a necessary part for 575 122ModC, (or at least the field version of the mod)

So then why is it MISSING from my circa 1962 575 Mod122C curve tracer?

The only conclusion I can draw is that it was an improvement made after 1962 and not a deletion. Otherwise, I can't come up with a reasonable way to explain why on my '62 model, and on others I see posted on TekWiki, it is absent. But in 1964 field modification kits, C239 was clearly specified and supplied.

Great! now I'm torn...
Maybe I'll just put one in and see if it creates a time-vortex or black hole or something. :-)

Keith
coolblueglow


Re: What is a mod BG to 7103 or 7104?

Mark Huffstutter
 

Nice get, John! And working too.

I recall a discussion a few years on MOD BG, but I don't remember whether
It was ever resolved. I will check the archive list. I seem to recall that Dennis
Tillman had found one.

Mark

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of John Griessen
Sent: Friday, August 20, 2021 9:46 AM
To: TekScopes@groups.io
Subject: [TekScopes] What is a mod BG to 7103 or 7104?

I just snagged this at auction in Albuquerque:

https://www.ecosensory.com/tek/7103-mod-bg.jpg

It even works!

So... what is mod BG?


What is a mod BG to 7103 or 7104?

John Griessen
 

I just snagged this at auction in Albuquerque:

https://www.ecosensory.com/tek/7103-mod-bg.jpg

It even works!

So... what is mod BG?


Re: OT- Need some info on special screw head(I've done more research)

Jim Ford
 

Ah yes, I bought ceramic screwdrivers from Vessel for an employer 15-20 years ago.  We were adjusting coils in an oscillator, and regular metallic screwdrivers skewed the frequency, and as soon as you moved them away, it would shift again.   Very difficult to adjust properly until we got the Vessel ceramic tools.        Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Karin Johnson <karinann@...> Date: 8/20/21 9:06 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] OT- Need some info on special screw head(I've done more research) First off thank you for the many replies.  I did some more research and found that the screw head type is called "Micro Stix".  I am guessing that this type is licensed or developed by a Japanese company called "OSG System Products".  Amazon has a variety of tools that will fit this screw head.The specific security head type is called 3ULR.  There are a few different sizes of the 3ULR pattern.  Also another Japanese company, "Vessel", has a variety of screw driver tools that will fit these screws.  I've ordered three of them of different sizes to make sure I have the proper one that fits the battery.Some of the responders have correctly identified the usage. It is on a Yaesu VX-5R handi talkie.Again, thanks to all who came to my help request.Karin


Re: Tektronix 575 122C trimmer capacitors

Dave Wise
 

They probably fixed it some other way in late instruments. Tek was constantly improving their designs, and sometimes this meant backing out an old fix in favor of a new one. You can buy scans of various instruments’ Mod Summaries from the VintageTek Museum. They’re interesting reading.

Dave Wise

From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Keith via groups.io
Sent: Thursday, August 19, 2021 3:57 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tektronix 575 122C trimmer capacitors

Hi Jeff,

O.K., so I get what you're saying, but I am still struggling to make this make sense. Beyond the obvious answer for "...what was C239?" (duh...a trimmer capacitor) The deeper question is this. Why was C239 considered important enough to put on all the instruments from 101-4769, and then unimportant enough to be mysteriously removed without apparent further notice?

Where I look, C239 was NOT a part of the regular build documentation as published in 1961. At least, I can't find it in there. Source for this observation is Version 1 of the 575 Manual parts manifest and schematics, capacitor list, Sec 8-1, pub. 1961. This manifest of electronic parts makes no mention of C239. In addition, adjusting C239 was not mentioned in the 1959 calibration document either. However strangely, C239 definitely IS called out, both as being present and requiring adjustment in the "Company Confidential" document called "575 Mod 122C Sup" from 1967! I find that reference on page 5, top of page, pub. 1967. In that document it explicitly states that C239 was present "...from S/N 101 thru 4,7xx."

So, is it possible that C239 was somehow only mentioned in manuals published before 1961, and then just totally deleted?

The bigger question is, what did C239 do? Why did they put C239 in units 101 through 4769 and then stop? And, is it possible that Tek sold over 4600 of these C239 equipped units between 1957 and about 1959? Wow! That's a lot of curve tracers. Of course, it was the beginning of the space race and all.

Ah, the mysteries of Tektronix!


Re: OT- Need some info on special screw head(I've done more research)

Karin Johnson
 

First off thank you for the many replies. I did some more research and found that the screw head type is called "Micro Stix". I am guessing that this type is licensed or developed by a Japanese company called "OSG System Products". Amazon has a variety of tools that will fit this screw head.
The specific security head type is called 3ULR. There are a few different sizes of the 3ULR pattern. Also another Japanese company, "Vessel", has a variety of screw driver tools that will fit these screws. I've ordered three of them of different sizes to make sure I have the proper one that fits the battery.
Some of the responders have correctly identified the usage. It is on a Yaesu VX-5R handi talkie.
Again, thanks to all who came to my help request.

Karin


Re: Quick Fire Report from BC

Lawrance A. Schneider
 

Just remember, donny and his like insist there is no such thing as 'global warming'. I truly fear for my grad children.


Re: 184 marker generator problems

Eric
 

My 184 will also drift up and down. When doing the calibration I have the
set point centered at 10 mhz. But the crystal will drift up and down about
15 hz due to the xtel oven heating and cooling. This is normal acording to
the spec sheet and within spec so totally happy with it. This effect is
observed hooking a frequancy count to the crystal out. Kind of cool. But
really hard to adjust with it constently moving.

Eric

On Wed, Aug 18, 2021, 1:44 AM Morris Odell <vilgotch1@...> wrote:

My thanks to all those who replied about this. The Russian 6 3 12 H-B
(english transliteration 6Z12N-V) equivalent tubes arrived yesterday. I got
8 of them including shipping for the cost of one genuine 7587 excluding
shipping. They look the same as genuine RCA nuvistors and the electrical
characteristics look very similar but they have solder-in leads rather than
pins and lack the asymmetrical locating lugs on the bases of real
nuvistors. The base pin/lead arrangement is the same. Date codes are 1979
and 1983. The leads looked like they had been soldered on to base pins but
they turned out to have been spot welded. I had to carefully clip them off
above the welds so they would fit into a nuvistor socket. Once I did that
and replaced the oscillator tube it worked just the same as with the
original 7587. However despite tweaking the various coli slugs and trimmers
it still needs the extra turn on the link to work properly. The oscillator
frequency once the oven has warmed up is within 10 Hz of 10 MHz (1 part per
million) which is more precision than I'll ever need.

I'm going to leave it like that. It's still a perfectly usable and
beautiful instrument. I don't need a marker generator often but when I do,
I now have a choice between the 184 and the later 2901.

Morris







Re: 475 with Vertical Amp problems?

Michael W. Lynch
 

To all who may have read,commented or made suggestions:

After a goodly amount of testing and work, I got the instrument to produce a coherent trace!

There were MANY things suggested by people in their comments. I checked most of these points and found no issues. Since all of the rails of the LVPS were in specs, I decided to leave any capacitors in place. The 9V diode was good. The 82V Zener tested good on the Type 576. I cleaned all the switches (again), since everyone (including myself) knows how problematic these can be. Tested the focus, intensity and astigmatism pots. Checked the CRT Plug and pins. Checked for voltages at the various CRT Pins. Checked the HV Multiplier output. Rechecked the -2450V. Checked the grid bias, it worked and was correct. Checked Vertical shield voltage adjustment and it was reasonable. Checked the CRT Vertical Plate resistor voltage for 50V. Rechecked all neck pin connections and connector wiring.

Applied the calibrator signal to the inputs, immediately found a "bad" X100 attenuator in one channel, replaced this and continued following the signal through both of the pre-amps . Traced the signal to the far end of the delay line and the signal came out clean on the other end at the Vertical output amp input. Since the signals tested at the Vertical deflection plates themselves were just HF noise riding on a +5-7 DC offset, I decided that the A5 circuit board MUST be the issue. I had another complete assembly that I know is good, rather than poke around trying to diagnose the various components in that difficult and confined location, I swapped the two boards out. This immediately produced a trace. Adjusted Focus, Astig and Trace rotation for a nice clean trace, however, there were still switching issues.

There were several strange behaviors, involving position controls, the BW Limit and various malfunctions of the ALT/CHOP/ADD functions. The Position, BW and some switching issues seemed to be the result of a cable that was installed "reversed". I found that the connector at P329 on the A4 Board was backwards. This cured most of the problems, but left a couple of issues with the ALT and CHOP which were subsequently traced to a "bad" U350. After replacing U350 with a known good IC, this restored the unit to full function. It is is now ready for calibration.

Questions or Comments welcomed!

Thanks to all who contributed. .

--
Michael Lynch
Dardanelle, AR


Convert tektronix 429pgm to 492p

diatel.maxim@...
 

I have tektronix 492pgm in pretty good condition and i'm happy with that instrument
and tekrtonix 492p non work but with all parts (some connectors broken, seems previous owner tried to repair 492p)
all RF parts, connectors, semi rigid cables etc in good conditions so i plan to use broken 492p as spare parts for 492pgm.
Do someone have some steps instruction or ideas is it really possible to add external mixer work for pgm using parts from 492p?
i expect software can be different, is it possible to switch pgm to p mode by some jumpers or i need another rom set?


moderated Re: Is Chuck Harris still on this group?

Reginald Beardsley
 

I am a paying supporter of this list (who had the perspicacity to only send Dennis $10 ;-) though I've not been reading it a lot lately. Likely to change as I just bought a 7904 :-)

If an individual who has a long history of useful participation is to be banned, I should like to ask that those of us who pay the bills be consulted. This means a specific complaint must be presented to those who pay the bills. And *we* shall judge.

It's a radical idea they developed in Athens over 2500 years ago.

Reg


Re: Connecting the Tek 7854 to a modern PC

tek_547
 

This looks very interesting Nenad and must be a lot of work. When the dark days are coming I dive in it.
René


Re: [OT] Low Temperature Solder

 

Unfortunately, I can't use any temperatures above 250C even for a
minute - brazing's totally out of the question. But I think the alu
which I'll be working on is probably made to be solderable, because it
has heatsink fins soldered to it. Thanks for the rundown.

On Fri, Aug 20, 2021 at 5:30 AM Roy Thistle
<roy.thistle@...> wrote:

On Thu, Aug 19, 2021 at 04:08 PM, cheater cheater wrote:


Should the flux that snapdiode posted earlier make it
possible to solder to 5000 and 6000 series Alu, or just 1000 series?
Part of the problem of "soldering" Al alloys (where "solderable") is getting enough heat in... as Al is a good conductor of heat... and good at radiating it too.
Preheating and using a hot source with good thermal capacity can help with that.
The other problem of concern is the oxides of both Al and Mg, in the Aluminium alloys.
I don't know what the flux snap diode is recommending... maybe a industrial chloride based flux?... but there are good fluxes for '"soldering" Al alloys, to Al alloys, that help to sufficiently control the formation of oxides. These fluxes may require "special" "solders" and special techniques, and high temperatures too, along with lots of heat. So depending on the alloy, mileage may vary. And you're tying to "solder" Al alloy to Cu (alloy?)... so these might not work.
Soldering the above with tin-lead solder isn't really a thing. Using the special solders, special techniques, and special fluxes is. I'm not saying you can't do it with tin-lead solder ... but, if there is Mg around it's going to probably require a very aggressive cleaning, and a very aggressive flux, and special soldering techniques. It won't be like electronic soldering with tin-lead solder.
Brazing is another way. Some people consider brazing just another form of "soldering".... usually metal workers. But melting a brass brazing rod onto a red hot copper joint, under a borax flux, in a slightly reducing acetylene torch flame... that's not what electronics guys usually think of as soldering. That's why it's sometimes confusing taking about "soldering".
There are flux cored Al brazing rods that are compatible with Al and Mg alloys. They are for brazing Al alloy to Al alloy... or maybe Al alloy to Mg alloy.
The HVAC guys braze copper tubing to Al tubing... there are flux cored Al brazing rods to do that.
Just in general,for joining Aluminium alloys, GTAW (or TIG) is the way to go. Welding is probably the norm.

--
Roy Thistle





Re: AA/SG mod summaries

Jean-Paul
 

Hello I have aller of them and could research my library for the documents.

The mil versions oscillator include the IM source from another SG505 osc rather have built in, and the filter you mentioned.

Design for testing radius systems.

Jon


Re: [OT] Low Temperature Solder

Roy Thistle
 

On Thu, Aug 19, 2021 at 04:08 PM, cheater cheater wrote:


Should the flux that snapdiode posted earlier make it
possible to solder to 5000 and 6000 series Alu, or just 1000 series?
Part of the problem of "soldering" Al alloys (where "solderable") is getting enough heat in... as Al is a good conductor of heat... and good at radiating it too.
Preheating and using a hot source with good thermal capacity can help with that.
The other problem of concern is the oxides of both Al and Mg, in the Aluminium alloys.
I don't know what the flux snap diode is recommending... maybe a industrial chloride based flux?... but there are good fluxes for '"soldering" Al alloys, to Al alloys, that help to sufficiently control the formation of oxides. These fluxes may require "special" "solders" and special techniques, and high temperatures too, along with lots of heat. So depending on the alloy, mileage may vary. And you're tying to "solder" Al alloy to Cu (alloy?)... so these might not work.
Soldering the above with tin-lead solder isn't really a thing. Using the special solders, special techniques, and special fluxes is. I'm not saying you can't do it with tin-lead solder ... but, if there is Mg around it's going to probably require a very aggressive cleaning, and a very aggressive flux, and special soldering techniques. It won't be like electronic soldering with tin-lead solder.
Brazing is another way. Some people consider brazing just another form of "soldering".... usually metal workers. But melting a brass brazing rod onto a red hot copper joint, under a borax flux, in a slightly reducing acetylene torch flame... that's not what electronics guys usually think of as soldering. That's why it's sometimes confusing taking about "soldering".
There are flux cored Al brazing rods that are compatible with Al and Mg alloys. They are for brazing Al alloy to Al alloy... or maybe Al alloy to Mg alloy.
The HVAC guys braze copper tubing to Al tubing... there are flux cored Al brazing rods to do that.
Just in general,for joining Aluminium alloys, GTAW (or TIG) is the way to go. Welding is probably the norm.

--
Roy Thistle


Re: OT- Need some info on special screw head

Michael A. Terrell
 

https://www.harborfreight.com/security-bit-set-with-case-100-pc-68457.html
is $10 and has those. It was on sale for $7.99 a few days ago.

Slotted : 3, 4, 4.5, 5 (2), 5.5, 6 (2), 6.5, 7, & 8mm
Phillips: #0, #1 (2), #2 (5), #3
Pozi: #0, #1, #2 (5), #3
Square: S0, S1, S2, S3
Star: T8, T10 (2), T15 (2), T20 (2),T25, T27, T30, T40, T45
Hex (19 pcs, 2 pc each): 1.5mm, 2mm, 2.5mm, 3mm (x3), 4mm, 5mm, 5.5mm, 6mm,
8mm
Slotted with center hole (4 pcs): 4mm, 6mm, 8mm, 10mm
Star with center hole (9 pcs): T8, T10, T15, T20, T25, T27, T30, T35, T40
Hex with center hole (6 pcs): 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm
Butterfly (3 pcs): #1, #2, #3
Tri-wing (4 pcs): #1, #2, #3, #4
Windmill (3 pcs): 6, 8, 10
M-type (3 pcs): M5, M6, M8 60mm
magnetic bit holder
1/4 in. x 50mm socket adapter
1/4 in. x 25mm socket adapter
1/4 in. x 25mm coupler
Y-shape hook driver

On Thu, Aug 19, 2021 at 8:40 PM Jeff Dutky <jeff.dutky@...> wrote:

You can get a set of three trueing screwdrivers on Amazon:
https://www.amazon.com/dp/B07DVQCZGP/ref=cm_sw_em_r_mt_dp_R9N4YHNAH1AVHHZ1AJ7W





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