REPAIR SUCCESS! Tektronix TDS5054 oscilloscope repair - PowerPC board hangs

[THDplusN_bad]

Good Day dear T&M equipment enthusiasts,

I am currently repairing a Tektronix TDS 5054 (non-B) digital oscilloscope and it seems that this one has a broken PC interface board alias PowerPPC board. Serial number is B04#######.

First off, I wanted to thank elektropionir for his write-up of his TDS 7104 repair and disk restoration setup https://www.eevblog.com/forum/testgear/tek-csa7404-repair-project/525/ and also harrimansat for his ISO images of a working TDS5054 with WinME OS. You guys rock.

https://www.eevblog.com/forum/testgear/$200-reward-for-information-regarding-tek-tds5000b-debug/msg3372734/#msg3372734
https://www.eevblog.com/forum/repair/help!-need-recovert-cd-for-winme-version-of-tds-5054/msg517232/#msg517232

So, the unit is the following state: In short, the PC interface board alias PowerPPC board fails and the Tekscope Application crashes with the known "Your Tektronix instrument has encountered an unrecoverable system error..." error message box.

Both LEDs CR700 'PAI LOADING' and CR710 'LOAD ERROR' on the PC interface/PowerPC board are permanently lit.
Might be Flash/EPROM rot...

I am including a detailed list of hardware and software installation troubleshooting I have done over the past days.

But as I am running out of ideas, I would certainly appreciate any pointers. For example, if any TDS5054 owner could measure signals are the various test points on the PC interface board, I could at least probe and confirm those.

As for the next step, I will take a day off and pause from this. Then disassemble the whole unit so I can insert the PowerPC board into a different PCI bus slot in the mainboard. This may also allow some testing of the PowerPC board in another PC, if possible...

Thanks for your support and bandwidth.

Cheers,

THDplusN_bad

General:

• The unit came with a crashing Tekscope program, but the Windows 2000 Professional OS booted and ran fine. The PC motherboard is an Intel D815EFV, 512 MByte SDRAM and a Pentium III  1.2 GHz CPU.

Hardware troubleshooting:

• I have cloned the HDD and replaced it with a 120 GByte mSATA solid state disk and a Delock type 62495 adapter (mSata to 44pin IDE); same as elektropionir I have used this adapter successfully for other repairs. Highly recommended.
  
• The primary symptom is that the start-up sequence of the PC interface board alias PowerPPC board fails. Both LEDs CR700 and CR710 are permanently on. LED CR710 goes low very briefly upon power-on, then lits up permanently.
  
• The USB connector J520 and the additional connector JP1000 from the PC motherboard to the PC interface / PPC board are fully and correctly inserted. The Front Panel passes all tests when tested with the Tektronix test application "FrontPanelTest.exe" as found in the /program files sub-directory.
  
• The LCD panel and the touch screen work well. All LEDs on the Front Panel light up for several seconds after power-up and then switch off permanently. 
  
• I have followed the Tektronix Service Manual 071-1004-02 and worked my way through the troubleshooting tree in figure 6-24 in the Service Manual. It basically ends at the last branch "Oscilloscope Application Starts?" Nope....
  
• I have measured the power supply voltages per Table 6-5 and 6-6, all voltages measured nominal.
  
• I have also removed the PC interface / PPC board and soldered test leads to the power supply section, and the +5V, -5V and +15V and -15V supply rails measure 5.53V, -5.4V, +16.4V and -16,3V DC. Tested the fuses F1001 and F1002, voltages are 5.08VDC on both sides each. The oscillator Y1700 produces a 14.3 MHz clock signal with 3.3Vpp signal amplitude. TP701 near U720 shows a 4.52 MHz clock signal with 3.5Vpp amplitude.
  
• All other testpoints on the PC interface/PowerPC board measure static low or 3.3V high.
  
• I have evaluated what happens if I press the RESET button on the PC interface / PPC board, same as grounding the test points TP1102 and TP1103 in Figure 6-27 in the Service Manual. No change.
  
• Set the test jumper J1100 to force permanent power-on, no change.
  
• The +5VA_unreg and -5V_unreg pins on the multi-pin interconnect between the PPC board and the acquisition board measure +5.42VDC and -5.48VDC.
  
• I have connected a 9-pin sub-D connector cable to the serial debug port J1050 close to the printer port, pins 2 and 8 (yes, two and eight) show no signal, but are permanently low at -9.8VDC.
  
• I had removed the acquisition board, which made no difference.
  

Software troubleshooting:

• I have checked all points per the "If the oscilloscope Application does not work" section on page 6-47 on the service manual, no change.
  
• The Tektronix VXI-11 server runs and is visible in the task bar. This was the case with the Windows 2000 OS and is the same with the Windows ME OS.
  
• I have removed and re-installed the two latest Tekscope applications version 1.1.5 and 1.2.1; one after de-installation of the other- no change.
  
• In the Windows device manager. I have removed and installed all Tek-specific drivers for the graphics card, changed the drivers for the PCI-to-PCI bridge and the Tektronix IO processor same as for the National Instruments PCI-GPIB adapter. All drivers were taken from the local c:\Tektronix directory. I have tried alternative drivers for the Tektronix IO board... No change.
  
• I have restored the original BIOS setting using the "EAAP18EB" tool as found in the c:\Tektronix directory. Same for the c:\Tektronix\CMOS tool, which I ran as "CMOS r -net" No change.
  
• I have carefully checked for any resource conflicts on the PC side/Windows Device Manager, and found no conflicts on DMA channels, IRQs or memory space.
  
• Screen resolution is set to 640 x 480, 16-bit color depth as per the Service Manual. Verified that the correct display adapter driver is used, as provided in the Tektronix subdirectory.
  
• My most recent stab into this was to restore the Windows ME image as kindly provided by harrimansat. The OS restoration has worked fine, same as for the installation of the TekScope Software release version 1.0.9. However, the primary failure remains the same...
  
• The GPIB port is not responsive and the lower VGA output produces the same signal as the internal LCD.
  TekVISA finds two resources, ASRL1::INSTR and ASRL2::INSTR - but these are just regular serial COM port aliases, so no sign of any real instrument detection.
  
• Changed the system date per jbruneaux's kind tip https://www.eevblog.com/forum/testgear/$200-reward-for-information-regarding-tek-tds5000b-debug/25/, but no change.

[THDplusN_bad]

Good Day to y'all.

Happy Friday.

I have prepared my desk for setting up the unit outside of its original enclosure, so I am looking forward to some probing and testing fun over the weekend. I remain confident that I can beat this thing into submission... 

However, if any fellow Tektronix TDS 5054 (B or non-B) owner could kindly provide me with some pointers, I would not mind it. 
It would be very helpful to know what signals are supposed to look like at the various test points of the PowerPC/PC interface board.
Pretty, please...

Thank you in anticipation and have a fine weekend, all.

Cheers,

THDplusN_bad

[sicco]

If it’s a PowerPC then it has the BDM port. Just as in the TDS3000 scopes. Quite likely that Tek use that port for loading the flash roms at factory. And for testing. BDM port on PPC lets you single step code, from reset onwards. To find the BDM pins, get the relevant PPC Freescale/NXP data sheet, locate the 6 or so BDM pins, and use a beeping multimeter to locate any connector / pin header that links to them. It’s sort of JTAG, PPC also has JTAG, it shares pins with that JTAG, but it’s the legacy BDM. Next you’ll need a BDM capable PC adapter. Such as the Abatron BDI2000/3000, or something with a FT2232 USB or equivalent. And PC software to use that BDM backdoor into the PPC. All of that i have and use for TDS3000 by the way. And can share.
In the TDS3000 series, it’s VxWorks as OS. Guess that’s still what you have in TDS5000 series.
Via BDM you can peek and poke RAM, ROM, i/o etc. And reflash/erase the ROMs. Provided the PPC has a clock and power supply. Which is the first thing to check anyway.

[THDplusN_bad]

Good Day,

other priorities have taken my time, but I have finally worked a bit on this one...


• Disassembled the whole unit and built a small wooden holder for the LCD, so I can test the unit on the bench ouside of its complex housing.
  This allows easy probing, at least of most connections. The acquisition board is quite heavy, and I am using some lego brick and a strap attached to the mainboard as stress reliefs. One of the fans is set-up to cool the acquisition board. Photos are attached.
• I had ordered another Intel D815E motherboard, in order to exclude the influence of the PC. The PCI bus of both boards produces a stable 33 MHz clock, and the other signals seem fine. Flashed the Tek-custom BIOS taken from the harddisk (which I had replaced with a 128 GB SSD as mentioned), but no change resulted when I used the 2nd PC main board.
• No joy on the failing PAI BOOT error on the PC interface / Power PC board. Probed all power supplies again, which appear fine at either 2.5V or 3.3V. The System reset and SYSCLK are hidden under large tantalum caps. No changes on the LEDs in terms of both LEDs CR700 and CR710 remain on. LED CR710 goes low briefly on power-up. The debug port remains static, i.e. TXD and RXD are static around -10V; static logic inputs on the MAX323 interface TxR
• The acquisition board features a "slave" ATMEL AT90LS8535 controller, which at least shows some activity on its PD2 to PD7 bus interface. Its other interfaces PC, PD, PA, PB and the SPI bus are static, same for the UART. The controller's main clock comes from a 3.68 MHz oscillator, that works fine. The /Reset signal for the Atmel µC comes from the Power PC board and it gets asserted/de-asserted from the reset button on that board just fine.
• There are two more oscillators on the acq. board, which I need to probe. It seems that at least the 10 MHz oscillator Y1302 is connected to some enable or switching circuitry, which I need to look at next. Y1302 produces no signal, which is suspicious; same for the canned oscillator Y1300. The latter might be the reference clock for the analogue front-end...
• U700, a large VLSI IC on the acquisition board gets really warm, not too hot to touch, but "unusually" warm with one fan blowing at it. I have not measured its temp yet, but I estimate the heat spreader reaches over 40 °C. Might want to use my IR meter to probe it later.
• I have probed the power supplies on the acq. board and all supplies are nominal. The resistance of the -5VA and +5VB supplies to GND measure pretty low, i.e. 61.4 Ohm for -5VA and 67.5 Ohm for +5VB. This is not a true short and it may be normal, but it appears fishy.
• In an attempt to isolate the problem to a section of the acq. board, I have removed most ferrites (used my trusty Pace ThermoTweeze for this, which still works like a charm); i.e. E501, E401, E760, E761, E770, E301, E201 and E202 on the solder side, and E502, E402, E302 on the component side were removed. This has brought the power supplies' resistance to GND up a bit, +5VA measured 100 Ohm, but +5VB still 67 Ohm. The Tantalum caps CS1740 and C1710 on these two supplies were removed, tested good and re-installed.


Next steps:
I plan to probe and trace signals for the two oscillators Y1300/Y1302 on the acq. board. Look for any components that may result in the low-resistance measurements of+5VA and +5VB to GND. I will proceed with removing the large caps and trace some signals so I can probe the SYSCLK and reset signal of the Power PC controller. If the PPC or one of the other VLSI ICs are toast, then this board is beyond repair...

Any pointers would be much appreciated. And thanks for reading through this continuing saga...

Cheers,

THDplusN_bad [/list]

[THDplusN_bad]

Good Day,

not much joy with this. I have checked several components and power supplies on the PC interface board. All supplies seem nominal when probed. The 33 MHz clock from the PCI bus probed fine and the connections from the Intel 21152 PCI-to-PCI bridge pass conductivity tests etc.
On the PC side of things, I have re-tested Windows ME as well as Windows 2000 OS. Both detect the NI GPIB controller and the "Tektronix I/O processor" just fine, with no resource or driver conflicts.
As a last resort I have "reflown" all accessible solder joints and completed an optical inspection with a Stereo Microscope. The PowerPC controller remains almost dead, with no signal activity to the associated DRAM or the debug port. The two LEDs CR700 and CR710 are permanently on after power-up and the /Reset button does not result in any reset condition. 

I have spent a serious amount of time cleaning the boards from flux and inspecting the board hardware for any faults. Nada...

With the PC interface board defunct, I cannot test the acquisition board. 

I am getting a helping hand from a kind soul, which might help me with some replacement boards. Let's see if I can get this machine back to work later this month.

Cheers,

THDplusN_bad

[THDplusN_bad]

Hello to the gang,

Ok, so I made a last attempt to repair the PC interface board for the Tektronix TDS5054 digital oscilloscope.
I am attaching some photos from my reflow "soldering adventure" earlier this week. This technique employs a simple hot air gun and it seems quite popular for repairing PC graphics cards. Dozens of YouTube videos about it. I am probably the last engineer in the world who has noticed this "trend" in PC repairs :-)
I could very gently move the PowerPC device at one point, so all solder was molten. And it moved back instantly. It has not caused any PCB burns and only a few components were slightly dislocated.. Fixed one dislocated transistor and completed an optical inspection afterwards. I ramped the temp. up slowly, it peaked at around 240°C/ at the top of the IC package until all solder was molten. Then gently cooled the thing down... I was positively surprised that the components on the backside of the PCB were not affected.

No success; however it surely was an interesting experience - and it worked very well for the first time. 

So, my theory about this failure is:

• The PowerPC does not boot the PAI code properly. Either the PowerPC device or its EPROM U1320 is defect or the XILINX SPARTAN FPGA U600 and/or its PROM U720 fails. https://download.tek.com/document/TDS5000B_MemoryErasure.pdf There is no data flow between the FPGA and its PROM.

A kind Tektronix enthusiast has sold me a known good PowerPC interface board and an Acquistion board that is partially working, but fails SPC. I am currently pending shipment, so expect more over-next week... 

It seems that I just cannot let go and sell this baby for parts only, can I... 

Have a fine Sunday, all.

THDplusN_bad

[THDplusN_bad]

Photos attached.

[THDplusN_bad]

Good Day,

so, it seems that this story will end well. I am happy to let you know that my TDS5054 is operational again. 

After the PC interface board was replaced, I have reverted back to Windows 2000 OS and installed Tekscope application or "Firmware" Rev 1.1.5.
With the power-up testing and SPC passing, I was happy to start with putting the unit back together. This is 85% completed now.

I am pending a replacement for the "Power Flex circuit", that's the power-on button with LEDs mounted on a flex cable. On my unit, the LED came off. Do not waste your time with any repair attempting with demister repair sets or similar. The solvent in these fluids will likely react with the flex cable substrate. Do not ask me how I know this... 

Here is a summary of my work:


• A kind fellow Tektronix enthusiast sold me a PC interface board or PowerPC board taken from a working unit. With this replacement, I was able to get the acquisition board back to life.
• The replacement board is an older HW revision that uses an "ORCA"-labeled Lattice FPGA; opposed to the Xilinx FPGA in a BGA housing in the later version.
• Some dependencies exist between the Hardware and the so-called "Firmware", i.e. the Tekscope application. For example, a combination of a "previous revision" PC interface board and a recent Acquisition board cannot be used with the Tekscope program Rev 1.0.9. Such a combination will fail power-up tests. Same for Tekscope revision 1.2.1, which is the most recent version to my knowledge. In this case, updating the Tek scope application would not do any good! Other incompatibilities may exist.
• I have installed the ferrites back on the acquisition board and have cleaned the board with great care. Used 70% IPA, destilled water, pressurized air and let the board dry on the heating over night. It was very rewarding to see the SPC pass after all the testing and some soldering work.
• I have replaced the large 92mm fans for the housing from NMB-MAT  with "Mistral" fans made by SilentiumPC. Similar specs for air flow and lower noise.
• The front panel was showing an error or an incompatibility with the older PC interface board. The "Cursors" button triggered the "touch screen off" button. So I have replaced the front panel and also installed the buttons that include a pink "FastAcq" button.
• One of the front panel encoders had a broken shaft. I have replaced this with one taken from the original front panel board. I have used a sharp knife to remove he molten plastic on the donor PCB, then removed and cleaned the rotary encoder. I have used two-component epoxy "JB weld" to glue the transplanted encoder and a soldering iron set to 190°C to melt the plastic for some mechanical support. See the attached pictures. Works perfectly.
• I cannot program another serial number into the PC interface board. According to the instructions in the Service Manual on page 6-57, GPIB command "HWAccountant:SERIAL 'serialnumber'" should allow this. I have tried all kind of syntax, also after issuing command "PASSWORD "XYZZY", but to no avail.
• For the benefit of other TDS50xx (non-B) users, here are the resistance readings from a working acquisition board. I am publishing this as I was surprised to learn that the relatively low resistances for the +5VA, -5VA and +5VB supplies are actually correct.

           All measured to GND with a Fluke 179 DMM:
          -15VA:   2.3k Ohm
          +15VA:  5.3k Ohm
          -5VA:     61.5 Ohm (Confirmed!)
          +5VA:    66.7 Ohm (Confirmed!)
          -5VB:     541 Ohm
          +5VB:    66.4 Ohm (Confirmed!)


• The serial debug port J1050 does not show any activity at power-up. It might require some jumpers or test point settings.

As you can imagine, I am very happy to see this unit operational again. A component-level repair of the PC interface board might have been possible, but would require replacement of components with BGA packages such as the PowerPC controller. That is beyond the repair equipment and/or skills of most hobbyists, I am afraid.

I have also tested the Ethernet and GPIB interfaces and was happy to find both operational. I am using a NI GPIB-USB-HS adapter and after completing some serious updates of NI488.2 and other NI software, the unit works well (with TekVISA and NI VISA). I have also created a simple Python script that produces hardcopies and transfers them via GPIB (altered some Python code from Tektronix). It seems that some other users had some problems with this, so I will post that code soon.

Greetings from Germany.

Cheers,

THDplusN_bad

[d-el]

Hello!
I'm upgrading TDS5104 (not B) to win XP.
We managed to install win XP and all the drivers.
To complete, I need TekScope installer 1.1.5 or 1.2.1.
I can't download it from https://www.tek.com.

Can anyone help me with the file?

[calibrationfixture]

Hi,

In my view to ambitious. TDS5000 Non-B are for Windows ME and 2000. The Recovery Disk Sets contains all necessary Drivers. With a plain Windows XP Installation you miss these. Nevertheless you said you installed all of them. In addition Scope Application V 1.2.1 needs the Later MB with the Processor Upgrade. To download Software you must register first. Just downloaded TDS5000 Product Software V 1.2.1. No problem with it now.

063-3509-02 Operating System Restore / v1.0.3 / winME / TDS5052, TDS5054, TDS5104
063-3509-03 Operating System Restore / v1.0.4 / winME / TDS5052, TDS5054, TDS5104
063-3509-50 Operating System Restore / v1.1.0 / win2000 / TDS5032, TDS5034, TDS5052, TDS5054, TDS5104
063-3509-04 Operating System Restore / v1.1.0 / win2000 / TDS5052, TDS5054, TDS5104

Success,

Calibrationfixture

[calibrationfixture]

Hi d-el,

Your PM Box is full. Please empty it.

Calibrationfixture