Author Topic: Tektronix THS7xxx Scope Hack/Teardown/Discussion - WANTED FW1.16 PLEASE HELP US  (Read 57750 times)

0 Members and 2 Guests are viewing this topic.

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS720A Portable Scope Hack/Teardown/Discussion
« Reply #100 on: November 19, 2016, 10:17:55 pm »
Damn, I'm so excited, here the resistors locations, photo courtesy of Zucca's teardown.



 
The following users thanked this post: nixxon

Offline R_G_B_

  • Frequent Contributor
  • **
  • Posts: 369
  • Country: gb
Re: Tektronix THS720A Portable Scope Hack/Teardown/Discussion
« Reply #101 on: November 20, 2016, 02:34:34 am »
Please could you post the screen capture of a 710A or 720A  showing as a 720P in power analyser mode.

Thanks 
R_G_B
 

Offline R_G_B_

  • Frequent Contributor
  • **
  • Posts: 369
  • Country: gb
Re: Tektronix THS720A Portable Scope Hack/Teardown/Discussion
« Reply #102 on: November 20, 2016, 02:36:11 am »
Also how easy would it be to get the firmware off of one of these things ?
R_G_B
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS720A Portable Scope Hack/Teardown/Discussion
« Reply #103 on: November 20, 2016, 04:20:43 am »
Also how easy would it be to get the firmware off of one of these things ?

In my eyes very easy. J1 is the magical connector  (Molex 15-92-2480, to be confirmed)

which give access to the

Quote
U1

IC, MEMORY; CMOS, FLASH ;1MEG X 8, 5.0
VOLT--ONLY, SECTOR ERASE;
AM29F080--120EC , 40PIN TSOPT&R

which has the FW in it. A TL866 should do the job, I think to keep the µC in Halt State by connecting pin 78 to 79 on J1 so it will not interfere when reading out the EEPROM.

Only thing I need is the freaking AMP 2x40pin 1,27mm pitch plug...

Maybe this one?
http://www.ebay.com/itm/2-AMP-80-Pin-Male-D-Sub-Connectors-from-Intel-2xx-Backplane-/160351413820

Anyone can tell me what AMP plug I need to buy?

This one? I think I got it.
http://www.ebay.de/itm/SCSI-Adapter-intern-68-Pin-auf-80-Pin-SCA-/291942990210?hash=item43f9288182:g:2msAAOSwiDFYKjQW
 
« Last Edit: November 22, 2016, 04:50:57 am by zucca »
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #105 on: November 20, 2016, 07:01:43 am »
Zucca, so are you saying, once the CPU's HALT pin is enabled externally through pin 78, while tapping the data bus (D0-D7) and the address bus (A0-A19) through the SCA connector, say connected to TL866 thru "creative" wiring at that SCA, we can read or write the flash AM29F080 ? CMIIW

Btw, just checked, TL866 supports AM29F080 officially.

Excerpt from MC68331 user manual :
Quote
4.4.1.10 Halt Signal
The halt signal (HALT) can be asserted by an external device for debugging purposes
to cause single bus cycle operation or (in combination with BERR) a retry of a bus cy-
cle in error. The HALT signal affects external bus cycles only, so a program not requir-
ing the use of external bus may continue executing, unaffected by the HALT signal.
When the MCU completes a bus cycle with the HALT signal asserted, DATA[15:0] is
placed in the high-impedance state, and bus control signals are driven inactive; the ad-
dress, function code, size, and read/write signals remain in the same state.
If HALT is
still asserted once bus mastership is returned to the MCU, the address, function code,
size, and read/write signals are again driven to their previous states. The MCU does
not service interrupt requests while it is halted. Refer to 4.5.5 Bus Exception Control
Cycles for further information.
 

Offline TurboTom

  • Frequent Contributor
  • **
  • Posts: 429
  • Country: de
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #106 on: November 20, 2016, 07:14:24 am »
Here some photos -- haven't yet assembled a serial cable to download the screenshots directly. Sorry for the poor quality, had to use the shitty cell phone camera  ::)

Cheers,
Thomas



P.S. Sorry, forgot to set date and time correctly...   ;)
« Last Edit: November 20, 2016, 07:17:54 am by TurboTom »
 

Offline HighVoltage

  • Super Contributor
  • ***
  • Posts: 3885
  • Country: de
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #107 on: November 20, 2016, 07:17:00 am »
That is impressive.

The THS720P is the one that always sells for the highest price on ebay.
There are 3 kinds of people in this world, those who can count and those who can not.
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #108 on: November 20, 2016, 07:17:33 am »
Oh yeah BravoV... that is my plan...
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #109 on: November 20, 2016, 07:24:59 am »
Here some photos -- haven't yet assembled a serial cable to download the screenshots directly. Sorry for the poor quality, had to use the shitty cell phone camera  ::)

Thomas, thank you so much, now I'm convinced. Definitely will mod my 710A, just by doing few resistors, free upgrade from 60Mhz to 100Mhz and extra harmonic analysis and power measurements features enabled.  :-+

Your firmware is 1.14 , wonder if my firmware 1.11 is enough for this mod ?

Btw, the latest is 1.16 isn't it from what I gathered from internet.
 

Offline R_G_B_

  • Frequent Contributor
  • **
  • Posts: 369
  • Country: gb
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #110 on: November 20, 2016, 09:58:47 am »
Looks like the firmware changes were about fixing bugs in the firmware ..

https://forum.tek.com/viewtopic.php

R_G_B
 

Offline TurboTom

  • Frequent Contributor
  • **
  • Posts: 429
  • Country: de
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #111 on: November 20, 2016, 10:33:55 pm »
When I received my (then) THS710A, both scope channels showed some DC offset that changed with the input sensitivity ranges selected. DC path compensation didn't correct this and I read somewhere in the forum that this is relateds to "worn out" analog optocouplers (CNR-201A) that are used to transfer the DC component of the input signal across the isolation barrier. Since these components are not particularly expensive. I decided to get some and replace them.

Guess what the result was: Same picture as before  :o

As a last resort I thought the complete factory calibration of the scope section might possibly help, and fortunately, it did the trick!  DC offset vanished completely. ;D

I just wanted to post the information in this thread since it seems to be the most comprehensive and as I understand, many of the THS700 models suffer more or less severely from the DC offset over the time. Calibration is very simple and all that's required for the job is a good (arbitrary) function generator that's capable of outputting a square wave with half-way decent rise time (<20ns) and a DC voltage (the accuracy of the latter should be checked with a reliable multimeter).  Fortunately, the scope section and the DMM section of the THS700 is calibrated separately and the DMM section calibration is very unlike to deteriorate over time.

All the information required for the job is available in the service manual, starting at page 51: http://de.tek.com/oscilloscope/ths720a-manual/ths710a-ths720a-ths730a-ths720p-service-manual

My recommendation in case of DC offset problems is to try this calibration before swapping out any components, especially since removal of the analog isolators is a real PITA....

Cheers,
Thomas


P.S. Some calibration steps really take some time and the instrument may appear like it's crashed -- just get yourself a cup of coffee (or whatever you feel like having at the time...) and wait. The screen contrast is set to 50% during calibration, on my THS700 this results in a rather dim screen (normally it's set at 65%), so don't worry if something like this happens.
« Last Edit: November 21, 2016, 06:25:34 am by TurboTom »
 
The following users thanked this post: BravoV, analogRF

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #112 on: November 20, 2016, 11:40:42 pm »
Looks like the firmware changes were about fixing bugs in the firmware ..

https://forum.tek.com/viewtopic.php

I searched, but can't find it ?  :-//

Anyway, if its bugs fixed, then I'm looking for 1.16 dump, anyone ?
 

Offline R_G_B_

  • Frequent Contributor
  • **
  • Posts: 369
  • Country: gb
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #113 on: November 21, 2016, 02:10:52 am »
Looks like the firmware changes were about fixing bugs in the firmware ..

https://forum.tek.com/viewtopic.php

I searched, but can't find it ?  :-//

Anyway, if its bugs fixed, then I'm looking for 1.16 dump, anyone ?

Try this
https://forum.tek.com/viewtopic.php?t=138280
R_G_B
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #114 on: November 21, 2016, 09:24:46 am »
As a last resort I thought the complete factory calibration of the scope section might possibly help, and fortunately, it did the trick!  DC offset vanished completely. ;D

Thanks for confirming again this:
https://www.eevblog.com/forum/repair/tek-ths720a-thinks-there-are-110v-on-the-input-but-there-is-just-a-50-ohm-r/msg870999/#msg870999

Mine has the same issue, but I want first to dump out the U1 AM29F080, then calibrate it. After I will compare the two U1 contents to understand where the calibration variables are. There will be surely a CRC, so not so easy... willl see.

 
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline 1audio

  • Contributor
  • Posts: 44
  • Country: us
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #115 on: November 21, 2016, 04:37:47 pm »
I have a really early THS720 (non-a) and 1) the 720P hack doesn't work. Moving the jumper turns it into a THS770??. No idea what that is and I saw no features of interest.

The PCB is different around the meter inputs and would not support later firmware with the external trig input on the meter terminals.

The display on this guy is really dim. Any options for getting a brighter display? LED upgrade? Newer tube or ???.

The best external software for these I have found comes from Metratek; http://www.metratek.com/  That software also works with a number of other scopes including my 7854. The "p" version gets the power measurement features like the 720P.
 

Offline HighVoltage

  • Super Contributor
  • ***
  • Posts: 3885
  • Country: de
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #116 on: November 21, 2016, 07:11:35 pm »

The best external software for these I have found comes from Metratek; http://www.metratek.com/  That software also works with a number of other scopes including my 7854. The "p" version gets the power measurement features like the 720P.
I have never heard of this scope software before.
Has anyone here used it?
How much is the real version?
There are 3 kinds of people in this world, those who can count and those who can not.
 

Offline 1audio

  • Contributor
  • Posts: 44
  • Country: us
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #117 on: November 22, 2016, 03:08:06 am »
Metrateks web site is not the easiest to navigate here are the prices: http://www.metratek.com/price.html  You can download the demo version to make sure it works for you. I had the Tektronix software for the THS stuff but it was little more than a screen grabber. You still need that serial connection. I believe a USB to serial adapter will work. However the popular chip comes in two versions, one that works in the old XP world and one in the newer Win 7-10 world. Usually you don't know which you are getting on the cheap adapters. I have wasted many hours figuring this out. This is a helpful guideline: http://www.usconverters.com/index.php?main_page=page&id=62
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #118 on: November 22, 2016, 04:50:06 am »
It looks like I found the J1 connector

Molex 15-92-2480

the dimensions match with the drawing here:

http://www.molex.com/pdm_docs/sd/015922480_sd.pdf

...still waiting for the Adapter board... but now I have more hope than before...  It should be the right one...
« Last Edit: November 22, 2016, 05:41:48 am by zucca »
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #119 on: November 22, 2016, 05:57:51 am »
Documenting the resistors mod, if you found any mistakes or not complete, just tell me, I will fix it accordingly.

Cmiiw, compared to 710A/720A/720P, it looks like 730A uses different AT1 and AT2 isn't it ? The ATx stands for attenuator ?  :-//
« Last Edit: November 22, 2016, 06:13:59 am by BravoV »
 

Online mk_

  • Regular Contributor
  • *
  • Posts: 127
  • Country: at
Re: Tektronix THS720A Portable Scope Teardown/Discussion
« Reply #120 on: November 23, 2016, 03:29:31 am »
I would also be interested in the little software app to capture the screen.

Best Wishes

Aurora

maybe this could be usefull...

Michael
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #121 on: November 26, 2016, 05:59:37 am »
FUUUUUUUUUUUU.....

Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 5354
  • Country: 00
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #122 on: November 28, 2016, 12:11:47 am »
Bummer  :palm: ... feel sorry for you Zucca.
 

Offline zucca

  • Supporter
  • ****
  • Posts: 1614
  • Country: it
  • EE Meid in Itali
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #123 on: December 08, 2016, 08:18:48 am »
It looks like I found the J1 connector

Molex 15-92-2480

the dimensions match with the drawing here:

http://www.molex.com/pdm_docs/sd/015922480_sd.pdf

...still waiting for the Adapter board... but now I have more hope than before...  It should be the right one...

well it is just BS! After further investigation it does  not match....

After two nights trying to find the right connector I give up... no way to find it on mouser or digikey. All the SCSI plugs are popping out... and our guy is not SCSI.
I found this

http://www.farnell.com/datasheets/1605497.pdf?_ga=1.116809280.799036234.1481144451

but it looks like it is not here either.

should I solder 40 cables on the back of that connector? Or buy another Plug+connector and desolder/replace the mister X J1 connector on the THS?

pffffff....
« Last Edit: December 08, 2016, 08:22:31 am by zucca »
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 

Offline TurboTom

  • Frequent Contributor
  • **
  • Posts: 429
  • Country: de
Re: Tektronix THS7xxx Portable Scope Hack/Teardown/Discussion
« Reply #124 on: December 08, 2016, 09:12:03 am »
Now that you already got that connector that' not wide enough apparently, why don't you just split it in half (place two slices of thin sheet metal between the contacts for protection and use a hacksaw between them to cut the plastic in half length-wise) and try to use the individual halves to make contact to the THS extension port. It may not work but it's worth a try I think.

Cheers,
Thomas
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf