Re: Quarter-turn panel fasteners
Do a search on ¡°Dzus fasteners¡± (yes, Dzus is the correct spelling). There is a wide variety of them from various sources. I am not familiar with the particular diameter and length of the ones that Tek uses/used. My recollection is that they have a slotted screw head. Steve H. On Sun, Dec 29, 2024 at 03:56 Richard Kelly via groups.io <richardjkelly= [email protected]> wrote: I¡¯m restoring a Tek 130 LC and will need to replace the above. On one side
the plastic piece (210-047) has broken which won¡¯t be hard to replace with
similar or a 3D print, but on the other the captive stop (105-009) has been
lost and all parts replaced with nasty bodges.
My question is: before spending lots of time milling/printing custom
parts, does anyone have either sources or recommendations?
Thank you.
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Re: Solder - Tin/Silver or Tin/Lead/Silver?
The Tek 500 tube scopes of 1950s...1960s include a small roll of the original Tek silver soldering for ceramic strip repair
The 25 mm roll is usually on the chassis top, see service manual.
The proper iron, tip and solder are all needed to prevent strip destruction
Jon
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Re: Quarter-turn panel fasteners
Hi again, will unearth my 130 LC, and compare the quarter turn twist lock to the ones on my 7000 MF scopes .
Am sure they are available, similar used in aviation, mil, etc.
Jon
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Re: Tektronix 454A Oscilloscope No Trace but Beam Finder works fine?
Bonjour,
Have used and fixed Tektronix scopes back to 1968, the first solid state portable 454, 453. Amazing these 50 years old scopes can still work at all. Most need a complete examination for tant and lytic caps,dirty switches and controls, and basic PS, CRT and HV check and cal.
Even if you fix the imm¨¦diat issues, expect the HV transformer, HV mult to fail with time.
So, reading this thread, it's a very an ineffective process, I suspect OP needs the full service manual, follow procedure and diagrams for a logical troubleshooting plan.
Bon chance
Jon
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Re: Quarter-turn panel fasteners
These sound like the ones used in the 7000-series scopes to secure the panels; however, I think they're not exactly the same, correct?
Barry - N4BUQ
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Hello Jon,
Yes the numbers I quoted are from the manual.
Indeed the red of the meter scale is almost gone so I will need to search out a
custom transfer option.
I don't see anything in MMc which would suit - it's not too hard to find
Zeus-type 1/4-turn that will work when you wish to fasten one panel to another,
but in this case, as you'll know, the fastener is 'on its own' and it is the
plastic arm on the reverse that engages with the chassis.
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Re: Quarter-turn panel fasteners
Hello Jon,
Yes the numbers I quoted are from the manual.
Indeed the red of the meter scale is almost gone so I will need to search out a custom transfer option.
I don't see anything in MMc which would suit - it's not too hard to find Zeus-type 1/4-turn that will work when you wish to fasten one panel to another, but in this case, as you'll know, the fastener is 'on its own' and it is the plastic arm on the reverse that engages with the chassis.
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Re: Quarter-turn panel fasteners
Tek LC 130meters are unique and very useful, meant to check scopes input capacity, can zero out any lead or cables capacitance. Beware the tired lytic and paper capacitors and meter scale deterioration . Ours is mint with original manuals and test fixtures.
Did you check Tektronix manual for the mfg and part number?
Try the enormous McMaster-Carr cat for "panel fasterers"
Bon chance
Jon
Jon
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Quarter-turn panel fasteners
I¡¯m restoring a Tek 130 LC and will need to replace the above. On one side the plastic piece (210-047) has broken which won¡¯t be hard to replace with similar or a 3D print, but on the other the captive stop (105-009) has been lost and all parts replaced with nasty bodges.
My question is: before spending lots of time milling/printing custom parts, does anyone have either sources or recommendations?
Thank you.
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Re: DSA 602, Still Relevant Today? Untimely response FWIW
Thanks for your words.
My secret is simple: it¡¯s name is ¡°Retirement¡±¡?
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Il giorno 28 dic 2024, alle ore 19:00, Adam R. Maxwell via groups.io <amaxwell@...> ha scritto:
On Dec 28, 2024, at 08:19 , Gianni Becattini via groups.io <Giovanni.becattini@...> wrote:
Triggered by the original post by be_moulton, I got a DSA and wrote some notes. Gianni,
That post was on 12 December, and you posted that you were expecting the DSA on the 15th. I'm not sure if I'm more disturbed that you found time to lay out 100 pages with text, photographs, tables, and diagrams in two weeks, or that you refer to it as "some notes." :)
Very interesting read that helped satisfy my curiosity about this beast, so thank you for your work!
Adam
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Re: Tektronix 454A Oscilloscope No Trace but Beam Finder works fine?
I¡¯ve been troubleshooting the oscilloscope further, focusing mainly on the Vertical Amplifier board. I¡¯ve attached pictures of the boards and the schematic diagram from the service manual, with two connectors marked because disconnecting them impacted the behavior (you need to log in to view these pictures): Main Board: /g/TekScopes/photo/299721/3870949/Verical%20Output%20-%20Circuit%20Board.jpg?p=Created%2C%2C%2C20%2C2%2C0%2C0Thick Film Hybrid Board: /g/TekScopes/photo/299721/3870951/Verical%20Output%20-%20Thick%20Film%20Circuit%20Board.jpg?p=Created%2C%2C%2C20%2C2%2C0%2C0Diagram: /g/TekScopes/photo/299721/3870950/Verical%20Output%20-%20Schematic%20Diagram.jpg?p=Created%2C%2C%2C20%2C2%2C0%2C0Here are my findings: 1. Disconnecting P442 completely resulted in a horizontal line at the screen's center. Adjusting the Vertical Position knob had no effect, and pressing the Beam Finder switch only shortened the line without changing its position. 2. Connecting only Pin 5 of P442 (+75V) gave the same result as disconnecting it entirely. 3. Connecting Pins 3, 4, and 5 of P442 also had the same result. 4. The line disappeared if Pin 1 or Pin 5 of P442 was connected. 5. Disconnecting P385 while P442 was fully connected caused the line to reappear. 6. Connecting only Pin 1 of P385 moved the line slightly upward. 7. Connecting only Pin 2 of P385 kept the line at the center. 8. The line disappeared if both pins of P385 were connected. 9. When the line was centered, voltages on the upper and lower rails matched closely. Looking at the schematic, the 'Thick Film Hybrid' board (btw, it's a PITA to solder on it) connects to the main vertical amplifier board via diodes VR363 and VR463 and through P385. Additional findings: 1. Feeding +12V to L369 and +75V to L385 simultaneously seemed to have caused the vertical deflection to malfunction. 2. Voltages at the emitters of Q314 (~6.27V) and Q414 (~3.67V) suggested the trace was off-screen. 3. When the horizontal line was centered, both emitter voltages were around -3.85V, a notable difference. At this point, I feel close to identifying the fault but am unsure which direction to take next. Any insights or suggestions would be much appreciated!
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Re: SC503 -12V power supply
Ozan,
Apologies for calling you Onan in a previous post!
I also installed a new 2N2219. But installing the 2N3565 was the part that brought it to life!
I will upgrade to a 2N2219A when it comes in.
Thank you sir! You taught me a lot in a short while!
Barry
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Re: SC503 -12V power supply
Hi Barry,
Good news. We did try shorting C-E of Q8051 and it didn't change the output, it should have eliminated any effect of Q8051 as the only root cause, i.e. there must have been something in addition to possibly bad Q8051. Perhaps the test was done before you fixed the broken traces and/or swapping 2N2219A. Congratulations for the repair, it was an interesting puzzle.
Ozan
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On Sat, Dec 28, 2024 at 07:25 AM, Barry Breaux wrote:
I finally got to the bottom of this! A great learning for me. The bottom line
is that the Q8051 transistor needs a lot of gain to drive 2n2219A. The
original transistor was a PN3565, 151-0341. The original was bad so I couldn't
measure it. I had only 2 of those on hand and the one with a gain of 465
worked.
Onan, Thanks for all the help you provided me. I am sorry if some of the
information I provided was a bit unclear. In the end I learned a lot. Many
thanks!
Barry
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Re: 80E04 sampling module - fair price?
If you do a Google search on "TDS8000" ... and click on 'images'... you will see that... about 90%... of those pictures show the TDS8000 frame sans the 'heads"
Now why is that?
I reckon... the heads are way more valuable then the frame.
That's just exactly my experience.
Having some working 'heads' ... it's relatively inexpensive to acquire a frame.
The other way around... not so much.
By the way... what does one do with just a TDS8000... without a 'head?'
One answer would be...if you are cynical... sell it on Ebay.
--
Roy Thistle
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Re: DSA 602, Still Relevant Today? Untimely response FWIW
On Dec 28, 2024, at 08:19 , Gianni Becattini via groups.io <Giovanni.becattini@...> wrote:
Triggered by the original post by be_moulton, I got a DSA and wrote some notes. Gianni, That post was on 12 December, and you posted that you were expecting the DSA on the 15th. I'm not sure if I'm more disturbed that you found time to lay out 100 pages with text, photographs, tables, and diagrams in two weeks, or that you refer to it as "some notes." :) Very interesting read that helped satisfy my curiosity about this beast, so thank you for your work! Adam
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Re: DSA 602, Still Relevant Today? Untimely response FWIW
Triggered by the original post by be_moulton, I got a DSA and wrote some notes.
You can find theme here: ,if you,like.
Any comment welcome, you are allowed to shoot the pianist...
Gianni
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Re: SC503 -12V power supply
I finally got to the bottom of this! A great learning for me. The bottom line is that the Q8051 transistor needs a lot of gain to drive 2n2219A. The original transistor was a PN3565, 151-0341. The original was bad so I couldn't measure it. I had only 2 of those on hand and the one with a gain of 465 worked.
Onan, Thanks for all the help you provided me. I am sorry if some of the information I provided was a bit unclear. In the end I learned a lot. Many thanks!
Barry
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Thanks!
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Il giorno 27 dic 2024, alle ore 16:34, Harvey White via groups.io <madyn@...> ha scritto:
If we're talking about the same thing, it's an overlay of multiple waveforms. What it shows is how long the transition takes and how uncertain it is (in time), and where the stable part of the waveform is.
One use is in communications where you measure the jitter of the channel (it's called an eye diagram there, IIRC). It is a good predictor of how well you can extract stable data from the stream. If there's no stable eye, forget the data.
so you get an indication that shows:
UNSTABLE...... STABLE....... UNSTABLE...... STABLE.......
and you want to sample the data in the middle of the "stable" area.
Harvey
On 12/27/2024 5:49 AM, Gianni Becattini via groups.io wrote:
Hi,
I am playing around with the DSA 602A and I am rather confused by histograms. I could create them, but I cannot imagine a way to make them useful (the manual does not say what they are for).
Surely this is a limit of my limited knowledge... would someone help me ?
Thanks
Gianni
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Re: Solder - Tin/Silver or Tin/Lead/Silver?
Hi Richard,
The lead free solder does indeed have a higher silver level and a considerably higher melting temperature than the usual silver-bearing leaded variety.
In addition to the preferred usage of silver, one of the other expressed concerns of Tek is the usage of excessive heat when working with the ceramic terminal strips.
I would think that so long as you use an appropriate wattage iron with good sized tip (ie with adequate thermal mass) you should be able to complete the soldering quickly without causing damage to the strip. Also, Tek has stated in their literature that for occasional repair work, regular tin/lead solder is acceptable.
Art
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80E04 sampling module - fair price?
Hi all,
After my TDS8000 eBay bargain turned out to be a nicely working unit, I¡¯m now looking for the expensive part, a Tektronix 80E04 sampling head.
I know those modules are for sale on sites like eBay, where they for 3K, 4K or even higher, if you filter out the broken ones.. But what do you guys consider a fair price for such a device?
If anyone has one for sale; please please let me know !
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Re: Solder - Tin/Silver or Tin/Lead/Silver?
I have used lead free solder with success on the ceramic strips. The solder used was Kester 24-7068-1402 Sn96.5 Ag3.0 Cu0.5. My current understanding is the issue is not the lead it is the LACK of silver cant say for sure so I don¡¯t have a large enough sample size but I have repaired a number of ceramic strip units with no trouble. 3% silver was the highest silver content I could find with out going highly exotic with highly exotic pricing. In terms of temp I used a really high powered iron Hakko FM203 with a thermal mass tip. I found the melting point of the solder to be less of an issue given how much heat the ceramic soaked out of the iron. I don¡¯t mind working hot with an iron but I am also used to working fast.
Zen
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of Richard Kelly via groups.io Sent: Friday, December 27, 2024 2:48 AM To: [email protected]Subject: [TekScopes] Solder - Tin/Silver or Tin/Lead/Silver? Apologies if this has been answered but I couldn't find in a search: I'm about to restore my first piece of Tek kit. understand the potential issue with the silver deposit ceramic strips and have electronic solder to hand that is 95% Tin, 3.8% Silver and 0.7% Copper. This appears to exceed comfortably the desired silver content, but it will be higher melting point (227 degC) than lead-containing variants. My question is "do I need to buy yet another reel of solder such as Sn62/Pb36/Ag2 which will be 179 degC melting point but lower silver or can I use what I already have?". Another way of asking: provided solder is silver-containing how much does temperature vs. silver content matter? Thnak you.
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Jean-Paul