Date   

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


Re: 2445A slow

Steve
 

On Sat, Apr 4, 2020 at 03:01 PM, Steve wrote:



--
Kind Regards,

steve


Meant to type Vishay not visual!


Re: 2445A slow

Steve
 

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.......

--
Kind Regards,

steve


Re: DAS9100 does anyone still remember it

Brian
 

Hi Dan , I will re-read that section of the manual . When I read it before I got the impression that all the mnemonics command did was read the data from the tape in the drive and acqmem again involved the tape drive . There was no mention of the form the data would take or needed to be . I will set the system up and try via GPIB to see what happens - if I have enough time tomorrow . I will let you know what I find .
Thank you for taking the time to help .
Brian

On Saturday, 4 April 2020, 19:39:19 BST, Dan G <dgajanovic@sympatico.ca> wrote:

Hi Brian,

I believe that the information you are looking for is contained in section 12 (GPIB Programming)
of the DAS 9100 Series Operator's Manual. A PDF is available in bitsavers.org's Test Equipment Archive,
as well as our TekWiki (w140.com).

In particular, I think you will be interested in the ACQMEM command to transfer the acquisition
memory to your computer, as well as the MNEMONICS command to transfer the Define Mnemonics
menu setup to and from the DAS mainframe.

As far as I know, DAS 9100 uses the RS-232 port as a poor man's GPIB interface, so these commands
should work over RS-232 as well, though I have not tested this myself.

According to the Tektronix 1985 catalog, Tek used to offer a suite of UNIX software tools (91DVV),
with source code (!), for generating test patterns and transferring data to and from the DAS.

Incidentally, I still have a working VAX system, so if someone has these old tapes gathering dust,
I would love to get a chance to preserve and archive them.


dan


Re: Ringing on 2235 100 volt supply

barry.ballenger@...
 

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

On Sat, Apr 4, 2020 at 1:37 PM John G <mnjgfl@centurylink.net> wrote:

The 6 mm is just a bit short. I cut a 4-4 screw about 7 mm long and it
worked perfect. Maybe the holes are slightly stripped.
Thanks for affirming it should be 6 mm.
John

On Sat, Apr 4, 2020 at 11:49 AM, <barry.ballenger@gmail.com> wrote:


john where is a pix of the screw from my scope, it is 6 mm long

On Sat, Apr 4, 2020 at 8:48 AM John G <mnjgfl@centurylink.net> wrote:

Thanks Barry, I have the screws somewhere in the scope, obviously not
in
the right place. The length would be helpful.
Thanks
John






Re: 2782 electrical schematics

evdsp39
 

Hi again,
No, the CRT tube is good  as I see all the information on the screen but completly unfocused.I suppose that the D/A are not working or perhaps the circuits arround this D/A.Because the current confinement it will unfortunately be bad for later...
Etienne.

Le mardi 31 mars 2020 à 04:50:13 UTC+1, Ernesto <ebordon@swbell.net> a écrit :

Hi evdsp39,

The manual in tekwiki has also plenty of block diagrams but no circuit diagrams.  (has Tektronix decided that circuit diagrams are obsolete??)

Did you get any response from the poster who has the circuit diagram at the other site you consulted,

https://forum.tek.com/viewtopic.php?t=135234&__cf_chl_jschl_tk__=dc56ddefd230acd93f9df188b708ab0c7f1bdfa0-1585625507-0-AUli2D36HpqZDRXn-ihg6gHacpOqzFNHDEmQrYFNPgH_kJ1htEG_qitoaRsN4qbrGkD5fIWZJ1M6hMcEmlFPd0e_fuHtwnO6JRYC7tWT1wsyLjOQb2qvBAe7RyDbn_K2OaWiz5NRRkNsF-6gZEaB_pAS__bQWkaY2o_40rHanBMI_pNg1bW9owRlllUguzCobQeejkSWAYd1ozrG91kGPa3l5LXoPR-CPDZtysPYAiCqinX-KAYDvIbupKa9fx6D6cEc5JdnIgOR6v1MeJX247DzL2FhBntGoq2MD5G8r_IJXiClcJIZ0BgvzFQg15tl90N_vf8sr6ExdFwBanxERAg5ONkr-4uTXrNdWZkG512H ?

When you say that focus, astigmatism and intensity are not working,  does this mean that the tube seems to be dead?
If you find no circuit diagrams,  can you go into the instrument and measure the voltages at the CRT, probably wrong or missing, and improvise a traditional high voltage supply for this CRT that at least lets you see something on its screen?


Re: DAS9100 does anyone still remember it

Dan G
 

Hi Brian,

I believe that the information you are looking for is contained in section 12 (GPIB Programming)
of the DAS 9100 Series Operator's Manual. A PDF is available in bitsavers.org's Test Equipment Archive,
as well as our TekWiki (w140.com).

In particular, I think you will be interested in the ACQMEM command to transfer the acquisition
memory to your computer, as well as the MNEMONICS command to transfer the Define Mnemonics
menu setup to and from the DAS mainframe.

As far as I know, DAS 9100 uses the RS-232 port as a poor man's GPIB interface, so these commands
should work over RS-232 as well, though I have not tested this myself.

According to the Tektronix 1985 catalog, Tek used to offer a suite of UNIX software tools (91DVV),
with source code (!), for generating test patterns and transferring data to and from the DAS.

Incidentally, I still have a working VAX system, so if someone has these old tapes gathering dust,
I would love to get a chance to preserve and archive them.


dan


Re: Ringing on 2235 100 volt supply

John G
 

The 6 mm is just a bit short. I cut a 4-4 screw about 7 mm long and it worked perfect. Maybe the holes are slightly stripped.
Thanks for affirming it should be 6 mm.
John

On Sat, Apr 4, 2020 at 11:49 AM, <barry.ballenger@gmail.com> wrote:


john where is a pix of the screw from my scope, it is 6 mm long

On Sat, Apr 4, 2020 at 8:48 AM John G <mnjgfl@centurylink.net> wrote:

Thanks Barry, I have the screws somewhere in the scope, obviously not in
the right place. The length would be helpful.
Thanks
John




Re: 2782 electrical schematics

evdsp39
 

Hi Ernesto,
Thank you very much for link ko4bb.com where I find  all the electrical schematics for the tek 2782 !So now I hope to correct my problem of focus and intensity ...
Have a good day.
Etienne.

Le mercredi 1 avril 2020 à 04:43:00 UTC+1, Ernesto <ebordon@swbell.net> a écrit :

Hi Bob,

Have you looked at these schematics at ko4bb.com?  The site looks very friendly and I was tempted to donate.  But the schematics are a different story.

Was this 2782 designed by Tektronix?  It looks like the mess of a mixture of digital and low level analog electronics.  I concentrated on the board A23 High Voltage Power supply Board.
This design is pure obscurity!  What is usually a straight forward simple interface to a CRT,  it seems to have been intentionally made more obscure by the introduction of a "module"  U10, which, sandwiched between the logic schematic and the CRT, leaves the logic in complete darkness.  This HV power supply is at least 10 times more complicated than the one in my 547 lab oscilloscope, (tube driven), and many times more complicated than the one in the 7704 mainframe which, in comparison, is clear like water.  But at least this 2782 circuit diagram shows some trimmers to adjust astigmatism and geometry,  so maybe evdsp39  may play with them and hopefully obtain a readable display.

Also what does not help is that these schematics, maybe the product of love and care,  have such a poor resolution that even with the Acrobat reader in 400% one cannot recognize most of the labels. But you should be thanked for the intention and these schematics are much better than nothing.

Ernesto


Re: 184 Time Mark Gen. - 2nS & 5nS not working

 

It would take the bandwidth of at least a 485 (350MHz) to verify the level of the 5 or 2 nS outputs. At 500 MHz, a well-tweaked 485 has a response down about 40%, so the 2nS output would measure less than 200mV if it meets spec. The vintageTEK Museum recently restored and sold a number of 184's. To do so required going through our entire stock of nuvistors with a curve tracer and picking the best ones for the 5 and 2nS outputs. Even then, tuning is extremely critical,and changes with the instrument in and out of the case. Also, the stages leading up to the highest frequency need to be tuned well -- LILO! Low in, low out.

--
Bob Haas


Re: Tek 576 Curve Tracer HV Replacement Transformer

 

Hi Michael,
Thank you for showing others what can be done by a dedicated member of TekScopes who refuses to let a valuable instrument collect dust.

Would your supplier be willing to make replacements for other Tek HV transformers where there is enough demand to meet his minimum order?

HV Transformers endure incredible electrical stresses and there are very few potting materials that are stable over a product lifetime that can last decades. They are all going to fail eventually.

Dennis Tillman W7pF



--
Dennis Tillman W7PF
TekScopes Moderator


Re: Ringing on 2235 100 volt supply

barry.ballenger@...
 

john where is a pix of the screw from my scope, it is 6 mm long

On Sat, Apr 4, 2020 at 8:48 AM John G <mnjgfl@centurylink.net> wrote:

Thanks Barry, I have the screws somewhere in the scope, obviously not in
the right place. The length would be helpful.
Thanks
John




Re: 465 dot only, no sweep

Mlynch001
 

You must have the correct Service Manual. Study the Circuit description section, starting with the power supplies. After that, all the LV supply voltages need to be correct voltages. Then and only then can you move to diagnose the problems with the sweep. Start at the bottom and work up, do not try to start in the center and work in all directions.

--
Michael Lynch
Dardanelle, AR


Re: 465 dot only, no sweep

 

Do you have the service manual? If not, Artekmanuals.com has the low serial manual.

My first guess would be check C1562, a 3000uF can capacitor on the main board.

Regards,

Tom, WA3PZI

On 4/4/2020 10:49 AM, james_55@mail.com wrote:
Hi all,
I have a early 465 which only displays a dot and only with the intensity high.
Reading the power supply voltages reveals that the -8v rail has -4.89v.
Does anyone recognise this situation?

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


465 dot only, no sweep

james_55@...
 

Hi all,
I have a early 465 which only displays a dot and only with the intensity high.
Reading the power supply voltages reveals that the -8v rail has -4.89v.

Does anyone recognise this situation?

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