Conversion of 500MHz TDS744A to 1GHz TDS784A

[nctnico]

You can attach some switches and just try every combination. Perhaps you need a different combination. It is also possible that a monochrome display (I assume the TDS540C has a monochrome display) isn't supported so there is no known model number for your configuration.

[Galen]

Thanks nctnico. I will need a few days to try this as time tied up these days.
The TDS580C published with the FW5.2 as stated in the tek document, so maybe the FW5.0 doesn't have the ID code for TDS580C.
But anyway, I will have a try.

[Alfons]

Here is a plot that shows the frequency response of my Tek744A-784A.
The device triggers cleanly up to over 1.5GHz, the signal also looks quite good, but the frequency response is already absolutely in the basement. The -3dBm is pretty close to 1GHz. The device is not calibrated. First Picture shows 1.5GHz in ET-Sampling, last Pikture shows 1.5GHz in Real-Time-Sampling.

[Galen]

Thanks nctnico. I will need a few days to try this as time tied up these days.
The TDS580C published with the FW5.2 as stated in the tek document, so maybe the FW5.0 doesn't have the ID code for TDS580C.
But anyway, I will have a try.

After I upgraded the firmware, the banner shows 'TDS580C'.  so shorting R1064 is right for TDS580C.

[Galen]

Has anybody tried TDS520C or 724C upgrade?

[madao]

2 ch and 1 Ghz exists, but only color display model. It is called as  TDS782.   (Firmware 5.2e support also  TDS782C. )

I have a   TDS724C aquisition board as good spare part, but i wouldn't try, it is not worth.

[Galen]

Thanks Matt.  I may try it someday.  but not now.

[olle]

Since I just noted that one of the (TDS754/784/...) acquisition board resistor configurations sets the scope to be a TDS794 (2 GHz BW on 1 channel), I wonder if anyone has tried that one out, and if so - did it work or brick the unit?

---
Real programmers: cat > a.out

[Jay_Diddy_B]

Olle and the group,

Welcome to the forum!!

I have just been checking the specification of the TDS794x family, The 794 is 50 only, which means it, (almost certainly) has different input section to the other 700 series family.

I have not seen the inside of the 794 so I don't know for certain.

Regards,
Jay_Diddy_B

[olle]

Thanks a lot for that piece of enlightenment. It means that I'll stay with my 754C-to-784C conversion for now.

 

Real programmers: cat > a.out

[Tantratron]

Thanks nctnico. I will need a few days to try this as time tied up these days.
The TDS580C published with the FW5.2 as stated in the tek document, so maybe the FW5.0 doesn't have the ID code for TDS580C.
But anyway, I will have a try.

After I upgraded the firmware, the banner shows 'TDS580C'.  so shorting R1064 is right for TDS580C.

What 5.x firmware version did you flash to have banner showing TDS580C

[Pete2]

I just got a 754A from Ebay. Paid too much for it because of postage and import VAT but that's the way it is. It is faulty, the infamous relays + dim CRT but at least I can retrofit an LCD if needed.

Anyway I found this topic and was considering the upgrade but I have no way to calibrate it so maybe I'll skip it for now. Also I am looking at a 754C and I assume it can have the 2M option. Is  this true? But I have to have a correct Acq board or can all of the C models support the high memory option? Any other reasons to choose 754C over 754A?

[Tantratron]

Hello Pete2,

Transforming the acquisition board of a 754 into 784 requires removing 4 capacitors and lengthy re-calibration. I assume but could be wrong that if you change faulty attenuator relays will introduce some parasitic capacitance so you'll be obliged to re-calibrate the 754.

In a few words, the TDS754A or TDS784A acquisition board is the same HW as the C series, the only difference concerns logic CPU board. The A runs with 68020 whereas the C serie runs with 68040 so it is just hacking process.

What country do you reside, how does it work with intra-european import tax ?

Albert