Date   

Re: Tek 576 Curve Tracer HV Replacement Transformer

 

Hi Dennis,

I am sorry if I made you waste your time over my rant. You probably have the fortune of having much life time ahead to acquire maturity and not get upset over the rant of an old man.

I have experience with excellence, but not in the consumer products market. I worked practically all my life for a service company in the oil industry, Schlumberger. If you are familiar with this industry, you must know that this company has always been and is by far the leader in measurements in oil wells, or "well logging". Its presence is all over the world. It provides excellent service to its customers, the oil companies, and they cultivate the relationship because this company can do things no other one can, important in a highly expensive environment. After working in the field, I designed for over 30 years all sorts of electronic equipment and data acquisition systems, so I know about quality and reliability in severe environments. This equipment has to work in the wells at a temperature range from freezing to 350 degF, under enormous pressures, support the banging of transportation to well sites and handling at an oil rig (people there are not suave), and yet make delicate complex measurements for long hours without failure. Rig time is very expensive, and a little failure can mean long hours of down time of the rig, at tens of thousands of dollars. Schlumberger has developed measurements using any imaginable physical magnitude, including nuclear magnetic resonance, to find, qualify and help extract that "black gold" from down there.

My former company does not sell its sophisticated equipment, it sells its service using it, at indecent high prices... (until now?). I used to do measurements non stop for up to 2 days at an oil well, and our customer was like God. It is the attitude of service or lack of it what drove my opinion of Tektronix, not the quality of their equipment. If so many VOLUNTEERS put their time to cultivate that legacy which helps hold high the image of the company, why cannot they have ONE person among their 4500 employees who is a liaison to these volunteers and their members, and shows interest for their problems and offers solutions?

BTW, I also have esteem for the 7854 oscilloscope, especially its service manual. I am reading it now to learn the principles of the early digitizing system. The inverter and HV supply are close to the ones in my 7704, and if I experience a failure in the HV transformer I will do like I did with the 547, find a solution around it, or build one myself, of course with the help of the TekScopes community.

Regards,
Ernesto


Re: 2782 electrical schematics

Abc Xyz
 

Does anyone know why the Schematic <9> for the Horizontal Section of the
465B I'd Missing from all Online Sources?

On Sat, Apr 4, 2020, 2:35 PM evdsp39 <evdsp39@gmail.com> wrote:

Hi,
Thank you for the link but there are only diagram of 2782...Anyway I
received from Ernesto the link where I find the complete electrical
schematics: ko4bb.com !
Etienne.
Le lundi 30 mars 2020 à 20:53:05 UTC+1, Mark Wendt <
wendt.mark@gmail.com> a écrit :

https://w140.com/tekwiki/wiki/2782

You'll find the service manual there.

Mark

On Mon, Mar 30, 2020 at 3:47 PM evdsp39 <evdsp39@gmail.com> wrote:

Hi all,I am new in this forum and I hope that I can find a solution to
my problem.I have a 2782 spectrum analyzer whom the focus, astigmatism and
intensity are not operating at all.I have the 2782 user manual but without
any electrical schematics, just a block diagram.So if somebody has these
schematics I will be happy to buy a copy !Thank you so much.Etienne.









Re: 2445A slow

Chuck Harris <cfharris@...>
 

Hi Steve,

For my own purposes, I don't think the WIMA caps used in
this scope's power supply really needed to be safety caps.
They have flameproof resistors in series with them, and
they are on the downstream side of a fuse.

But, for my customers, I always try to meet or exceed the
original safety mechanisms the manufacturer provided.

A film X2 safety cap is what I always use in these supplies.

Remember these safety caps are rated for AC volts. Most
other caps are rated for DC volts. You have to divide the
DC rating by 1.4 to get the AC rating. If the cap doesn't
say it is a safety cap, and give its safety rating, it isn't.

The scope in X-Y requires that you change the X value, and
change the Y value to get a display. Because your scope is
showing nothing but a 45 degree line, I can tell instantly
that whatever you are doing is putting the exact same waveform
on both axes ( channels).

If you are connecting your scope to a curve tracer, you need
two BNC cables from the curve tracer, and they have to connect
one to CH1 or X, and the other to CH2 or Y.

-Chuck Harris

Steve wrote:

Thanks for that lesson in capacitance I'm in no way being snobby when I say this but that was excellent information that I haven't been privy too until you told me that in your message concerning upping the value of capacitance, so thank you VERY much for the education. I keep like I said Nichicon UPW series low esr high ripple on hand to re cap most all of my jobs so I'm going to assume that those will work by your message. I have some visual and Wima film style caps as well as some ceramic discs caps. I hate to ask a redundant question but would the film type caps be suitable for the safety caps or should I go with something different? I plan on recapping the LV supply today. I'm not familiar with the other part of the scope that needs recapped as well matter of fact I'm not quite sure what to look for ( Anode supply board) I have most all of the values that you listed for the LV supply and I purchase all my parts from mouser. I have some 1uf Wima film caps if that would work for the one bipolar cap. I'm not sure I have the other film caps in the specified voltage values but I'll look. Also, I did as you said about not pressing any channel buttons in xy mode but all I get is an angled line with no comb from transistor specs. I'm positively sure it's operator error as I get a good readout on my digital scope it's just real grainy and hard to read hence me purchasing this scope, primarily to use my curve tracers with.......


Re: 2782 electrical schematics

evdsp39
 

Hi,
Thank you for the link but there are only diagram of 2782...Anyway I received from  Ernesto the link where I find the complete electrical schematics: ko4bb.com !
Etienne.

Le lundi 30 mars 2020 à 20:53:05 UTC+1, Mark Wendt <wendt.mark@gmail.com> a écrit :

https://w140.com/tekwiki/wiki/2782

You'll find the service manual there.

Mark

On Mon, Mar 30, 2020 at 3:47 PM evdsp39 <evdsp39@gmail.com> wrote:

Hi all,I am new in this forum and I hope that I can find a solution to my problem.I have a 2782  spectrum analyzer whom the focus, astigmatism and intensity are not operating at all.I have the 2782 user manual  but without any electrical schematics, just a block diagram.So if somebody has these schematics I will be happy to buy a copy !Thank you so much.Etienne.





Re: Capacitor testing

Randy Newman
 

Hi Roy:
I have ( in my previous work lives) reviewed various of the MIL-Cxx spec’s, and remember reading about reforming electrolytics. Sadly, I have forgotten the one containing the reforming procedure. Which particular spec are you referring to?
Btw..I have a Systron Donner 320v, 2A supply which I have been waiting to use on reforming.
The proverbial “one of these days....”


Re: Tek 576 Curve Tracer HV Replacement Transformer

Errick
 

Dennis,
Very well said.

Michael,
Can you tell us who the manufactured the transformers?


Re: TDS7054 not booting

amirb
 

at what stage does it stop booting? why dont you go into the BIOS and change the boot device? just press Del or F12 or Ins or etc....key at startup to get to the BIOS
also connect an external monitor at the back if the LCD screen is blank

also pay attention to the one digit 7 segment on the PPC board and see what numbers it displays during the boot. This will tell you the kind of error it is facaing


.


Re: 465 dot only, no sweep

james_55@...
 

On Sat, Apr 4, 2020 at 08:44 PM, Bill wrote:


More than likely a capacitor has shorted. Probably a Tantalum.
Bill
Don't think so, as if it was shorted the voltage would be close to zero.

But thanks


Re: 465 dot only, no sweep

james_55@...
 

On Sat, Apr 4, 2020 at 04:12 PM, Tom Miller wrote:



My first guess would be check C1562, a 3000uF can capacitor on the main
board.
That was what I was testing in another thread, and it seemed ok.


Re: Tek 576 Curve Tracer HV Replacement Transformer

 

Hi Ernesto,

It is probably a waste of my time to reply to your rant. My conclusions, from reading your comments are:
1) You haven’t got a clue what it takes to run a successful business.
2) You only think of yourself.
3) You think everything should be available forever at a price acceptable to you.
I decided to reply because I hope to learn something I don’t know. You clearly have an issue with the way Tek runs its business; ergo there are companies that run their businesses at least as well, or better, than you were expecting from Tek. I expect you to name one or more of those companies to justify your rant. I, and the other members of TekScopes, will benefit from learning which companies you have dealt with that provide the customer service and support you came to expect from Tek. So please answer the following question so we all may know who you recommend for their support and service:
-----------
Name me a company that maintains an inventory of spare parts for anything they built 50 years ago. Be sure to include only the companies that provide this service for individuals who paid less than 5% of the original cost of the instrument and who will expect the spare part to likewise cost 5% of its original manufacturing cost.
-----------
When the HV Transformer on my favorite scope, a 7854, failed this was simply not an acceptable situation. Unlike you I didn't expect a company that once was known for its stellar support to carry a spare part 30 years later just for me. I didn't disparage the company for not designing this part so it could last past my death 50 years later. Instead I got off my butt and called the manufacturer of the part listed in the Tek manual. I gave them the part number and I asked for a quote. They contacted me a few days later to say they would be happy to make a batch of them for only $425 each with a minimum order of five. Their quote was not unreasonable. Should I have explained to them that although this 7854 cost $10,000 new I bought it on eBay for $400? Therefore the replacement transformer should only cost $400 / $10000 = 4% of its new price, or $425 * 4% = $17. Do I dare follow this up by saying I only want to pay for one? Would they still be in business 30 years after the scope was made if they sold their transformers on eBay for $17? If I had told them Ernesto expects them to make it for around $17 would they have taken his opinion into consideration or would they have shown me the door?

If you have an issue with Tek or the way they run their business there are other companies who make similar products, but I doubt they have the incredible support network we do from the vintageTEK Museum, TekWiki, TekScopes Forum, and Tek’s own Service Manuals. Keep us posted on what you find. If you find something better we will all be interested in hearing about it.

I, for one, know how extremely fortunate I am that there once was a company whose dedication to quality, exceptional engineering, and excellence in everything they did, resulted in instruments that still work as good as they did 40, 50, even 60 years after they were built. Their legacy lives on with the support we receive from the volunteers at the vintageTEK Museum, the incredible creation of Kurt Rosenfeld who gave us TekWiki, Michael Dunn who recognized the need 20 years ago for the TekScopes Forum, and the amazing Service Manuals that Tek produced to support every instrument they made. I would be remiss if I didn’t include eBay. It would not be possible for us to own these incredible instruments without the marketplace they created for used Tek equipment 25 years ago.

Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Ernesto
Sent: Saturday, April 04, 2020 7:21 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tek 576 Curve Tracer HV Replacement Transformer

<SNIP>
(Rant-mode-on) If mlynch001 can be a source of replacement transformers, WHY CANNOT Tektronix have been the one?
Don't they feel any responsibility for their products? A part they manufactured with an OBVIOUS defect that can totally disable one of their expensive instruments?
If Michael could find a manufacturer, could they not have taken an infinitesimal part of their huge development and manufacturing facility to make these transformers?
And they didn't need to lose money. If not free, they could have delivered this parts at cost. For all their old scopes that have this HV transformer problem.
As my esteem for the old Tektronix instruments increases, my regard for Tektronix Inc with its over a billion dollars revenue keeps falling.



--
Dennis Tillman W7PF
TekScopes Moderator


Re: Ringing on 2235 100 volt supply

John G
 

Barry,
BTDT. I missed plugging in one of the ribbon cables.
John

On Sat, Apr 4, 2020 at 03:00 PM, <barry.ballenger@gmail.com> wrote:


Same here worked fine then quit when I put it back in to test. Have you
worked on any attenuator boards. Looking for what might be wrong on mine.


Re: Capacitor testing

Roy Morgan
 

Long and expert experience with Collins amateur equipment tells us to limit the reforming current to FIVE MILLAMPS.

Take your time. Monitor cap voltage and reforming current. Be patient.

I have a Heath variable bench supply - DC variable from about 0 to 300 volts or so, I use a 10k or 5K, 5 or 10 watt resistor in series. The current meter on the supply lets me keep reforming current low, and a separate voltmeter shows me the caps progress.

Do not follow the procedure given in the MIL-HANDBOOK on reforming electrolytics. There is real danger of disaster doing that (Parallel many caps, reform them with a light bulb series with a DC supply, limiting current to the total for all caps.)

Roy


On Apr 4, 2020, at 5:14 AM, james_55@mail.com wrote:

Hi and thanks for the sugestion.

Any recommendation as to the resistor value?

1k 100k?

Roy Morgan
K1LKY since 1958
k1lky68@gmail.com


Re: Ringing on 2235 100 volt supply

barry.ballenger@...
 

Same here worked fine then quit when I put it back in to test. Have you
worked on any attenuator boards. Looking for what might be wrong on mine.

On Sat, Apr 4, 2020 at 2:47 PM John G <mnjgfl@centurylink.net> wrote:

I removed it when I re-capped everything.

On Sat, Apr 4, 2020 at 01:55 PM, <barry.ballenger@gmail.com> wrote:


John did you have the attenuators board.out to repair. My B channel quit
working and believe it may be the B attenuator board.



Re: OT Seeking Sencore CA55 Capacitor Analyzer CA55

Roy Morgan
 

From a discussion three years ago on Antique Radio Forums:

https://antiqueradios.com/forums/viewtopic.php?f=8&t=318097


Post subject: Re: Sencore CA55 capacitor testerPosted: Mar Sun 19, 2017 4:10 am
Member

Joined: Sep Tue 30, 2014 6:08 am
Posts: 5333
Location: Norfolk, VA
Micro Precision Calibration has the manual, and apparently will make a copy of theirs for a fee. http://www.microprecision.com

Back a few years ago, I was asked about the CA55 ( I have a working LC102 and two dead LC53s) and found them on the web. Feedback was that the guys who needed the manual for the CA55 were able to purchase a manual copy from them. They have a ton of locations, so patience in dealing with them was the key. I have no affiliation with them at all.

_________________
Brian
"Capacitor Cosmetologist since 1979"
USN Retired 1984-2006 (Avionics/Cal)


On Apr 4, 2020, at 3:23 PM, Yiu On Tony C via groups.io <tonycheung_hk=yahoo.com@groups.io> wrote:

Dear Members :

I am sorry , it is OT topic, I am being seek the manual/ schematic/ calibration information etc....

CA55 of Sencore is a capacitor analyzer, I cannot find related service information on web site .
Roy Morgan
K1LKY since 1958
k1lky68@gmail.com


Re: 465 dot only, no sweep

Abc Xyz
 

What would cause Both Traces to be Shifted Right on a 465B?

On Sat, Apr 4, 2020, 12:44 PM Bill via groups.io <ko4nrbs=
yahoo.com@groups.io> wrote:

More than likely a capacitor has shorted. Probably a Tantalum.
Bill




Re: Ringing on 2235 100 volt supply

John G
 

I removed it when I re-capped everything.

On Sat, Apr 4, 2020 at 01:55 PM, <barry.ballenger@gmail.com> wrote:


John did you have the attenuators board.out to repair. My B channel quit
working and believe it may be the B attenuator board.


Re: 465 dot only, no sweep

Bill
 


Re: 465 dot only, no sweep

Bill
 

More than likely a capacitor has shorted. Probably a Tantalum.
Bill


OT Seeking Sencore CA55 Capacitor Analyzer CA55

 

Dear Members :

I am sorry , it is OT topic, I am being seek the manual/ schematic/ calibration information etc....

CA55 of Sencore is a capacitor analyzer, I cannot find related service information on web site .

Regard
Tony Cheung
APR 5 2020


TDS7054 not booting

Tom B
 

Hello All,

I have an old TDS7054 (windows 98) that hangs while booting. The problem seems to be that it is looking for a Banyan vines network.  Could someone tell me how to keep it from trying to boot using files from the network?  Booting in safe mode I found the registry entry for the file, but I don't just want to delete the entry.  So, given that it is windows 98, what do I do to fix the problem?

Tom Bryan

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