The "older" interface with the BNC and multiple supplies is called the TekProbe Level II. Level I was the unpowered BNC with the 10x/100x sensing ring around it. Glad to see you got the old unit working (cloned from a working unit).
HP also had that type of probe interface with one pin contacting a ring around the BNC jacks on the scope. If you connect a 10:1 HP probe with that interface to a Tek Scope, the Tek gets confuesd and shows totally wrong scaling factors. I tested this with my Tek2445 and the readout thinks that this is 100:1 probe.
@@Thesignalpathafter L2 followed the L3 interface enabling things like automatic probe control. The VPI and also the revised VPI+ as well as the TekConnect interface in fact still follow the TekProbe standard even to Level 1 which was the original probe sense ring you find on scopes like the 24xx series. Funfact is that even the high end Sampling Modules of the 8000 series basically use a modified and heavily extended version of TekProbe L-III. By now the interface also contains a high speed mode to send S-parameter data from the probe to the scope. This is used for example on the TDP77xx Series which is the High speed probing platform for the MSO6 Series.
Interesting and fairly complex for a little adapter. Good on Tek for having legacy probe compatability with newer boxes. Now if we can get the industry to standardize on scope smart probes...
I also had repaired few of these TekVPI adapters, and actually had one blown (TI TPS LDO regulator died) during my playing with older Tektronix ADA400A differential preamp. ADA400A designed for older TDS700 series, and had some large current spikes at gain switch change with ADA400A connected to TekVPI.
Is there a different situation or different scope when attached the duplicate serial numbers would matter?......... I can't help wonder why Tek would apply a serial number system to them in the first place.
This probe is a passthrough as far as the analog signal is concerned. But other probes, active probes for example, have calibration coefficients or custom zero settings, in those cases the scope remembers those settings based on the serial number. So if you disconnect a probe from one channel and plug it into a new channel, you don't need to recalibrate or apply the settings. They would follow the probe. This is how Keysight does it. In those cases if you plug the same serial number probe into the scope, it would flag an error.
I picked up a couple of these for cheap on eBay a while back and I thought they're just overpriced through connections. Who knew there'd be a processor and multiple PCBs in there!
It seems like it was just old firmware, maybe possible these units escaped from Tek bringup lab or something since it seems like the firmware is early enough such that it didn't even function really.
The earlier ones had eeprom corruption which is super common on atmega, as the processor can write random junk to eeprom during brownout. Usually best is if brownout protection is enabled, which it may not have been.
Always preferred the Tek interface. But the only 1GHz scope I could afford (~$400) was an old LeCroy 9374 (I needed the analog bandwidth to repair an old pulse generator). The Interface has 6 pins and no locking rings on the BNC, but retention clips/springs. Plugging and unplugging the 2GS/s adapter (basically a 50Ω power splitter for Ch2&3) feels horrible because you basically just shove it in there. It's so hard you actually have to hold that brick of a scope down, otherwise you'd just pull it off the table. The worst thing is, since teledyne bought LeCroy they haven't even made an attempt of improving this horrible interface. And to be honest I think the company went to S**t after it was bought up.
I have shown it in previous repairs of Tek probes. It is not a difficult thing at all - just connecting the programming header to the dedicated pins already on the probe PCB. You can then read the flash as well as the EEPROM.
The "older" interface with the BNC and multiple supplies is called the TekProbe Level II. Level I was the unpowered BNC with the 10x/100x sensing ring around it. Glad to see you got the old unit working (cloned from a working unit).
Thank you Alan!
HP also had that type of probe interface with one pin contacting a ring around the BNC jacks on the scope. If you connect a 10:1 HP probe with that interface to a Tek Scope, the Tek gets confuesd and shows totally wrong scaling factors. I tested this with my Tek2445 and the readout thinks that this is 100:1 probe.
@@Thesignalpathafter L2 followed the L3 interface enabling things like automatic probe control. The VPI and also the revised VPI+ as well as the TekConnect interface in fact still follow the TekProbe standard even to Level 1 which was the original probe sense ring you find on scopes like the 24xx series. Funfact is that even the high end Sampling Modules of the 8000 series basically use a modified and heavily extended version of TekProbe L-III. By now the interface also contains a high speed mode to send S-parameter data from the probe to the scope. This is used for example on the TDP77xx Series which is the High speed probing platform for the MSO6 Series.
I'm happy there's no digital rights management keyed crypto layer between these probes and adapters and scope
Interesting and fairly complex for a little adapter. Good on Tek for having legacy probe compatability with newer boxes.
Now if we can get the industry to standardize on scope smart probes...
I really like the fact, that it seems quite easy to dump the firmware.
I also had repaired few of these TekVPI adapters, and actually had one blown (TI TPS LDO regulator died) during my playing with older Tektronix ADA400A differential preamp. ADA400A designed for older TDS700 series, and had some large current spikes at gain switch change with ADA400A connected to TekVPI.
Chaps, pretty much an EE and computer professor, he can also repair X-ray machines, this is trivia. All the best for '24 Shariar.
How were you able to read the program from MCU? Did they not set lock fuse bits? This is very strange.
No, luckily no lock fuses are set in Tektronix probes.
@@Thesignalpath Don't give them any ideas. 🙊
good content.
Is there a different situation or different scope when attached the duplicate serial numbers would matter?......... I can't help wonder why Tek would apply a serial number system to them in the first place.
This probe is a passthrough as far as the analog signal is concerned. But other probes, active probes for example, have calibration coefficients or custom zero settings, in those cases the scope remembers those settings based on the serial number. So if you disconnect a probe from one channel and plug it into a new channel, you don't need to recalibrate or apply the settings. They would follow the probe. This is how Keysight does it. In those cases if you plug the same serial number probe into the scope, it would flag an error.
hey, guys!
Alles bestens in 2024!
Hyvää utta vuotta! Bonne Anéé!
The 🇨🇦 🐻 in 🇩🇪
I picked up a couple of these for cheap on eBay a while back and I thought they're just overpriced through connections. Who knew there'd be a processor and multiple PCBs in there!
What might have caused the firmware to become corrupted, or lost?
It seems like it was just old firmware, maybe possible these units escaped from Tek bringup lab or something since it seems like the firmware is early enough such that it didn't even function really.
The earlier ones had eeprom corruption which is super common on atmega, as the processor can write random junk to eeprom during brownout. Usually best is if brownout protection is enabled, which it may not have been.
Always preferred the Tek interface. But the only 1GHz scope I could afford (~$400) was an old LeCroy 9374 (I needed the analog bandwidth to repair an old pulse generator). The Interface has 6 pins and no locking rings on the BNC, but retention clips/springs. Plugging and unplugging the 2GS/s adapter (basically a 50Ω power splitter for Ch2&3) feels horrible because you basically just shove it in there. It's so hard you actually have to hold that brick of a scope down, otherwise you'd just pull it off the table. The worst thing is, since teledyne bought LeCroy they haven't even made an attempt of improving this horrible interface. And to be honest I think the company went to S**t after it was bought up.
👍👍👌👌
You didn't demonstrate how to get the firmware off and how to get it on the new probe😢
I have shown it in previous repairs of Tek probes. It is not a difficult thing at all - just connecting the programming header to the dedicated pins already on the probe PCB. You can then read the flash as well as the EEPROM.
My God! Even the adapter has got a firmware that needs to be updated, electronics are loosing the fun.