Hi guys!
I have my repaired TDS7254B booting successfully (which is much thanks to the fantastic content of this thread) but it requires an acquisition board repair - the analog mux for ADCs has a connection problem. About a year ago I removed the heatsink and reflowed the BGA back on the acquisition board, and the problem was fixed!
Long story short, I was tinkering this weekend and noticed the same problem re-appearing. I am going to attempt to remove and re-ball the BGA with leaded solder as it seems as if the exact same failure happened again after a year of use - likely thermal cycling related. Anyway, this is a very risky operation to perform as Tek won't even sell or support one of these acq boards. I looked on ebay at replacement acquisition boards should this open heart surgery not go well. Below is a list of purchasable options, now the problem is figuring out which scopes each board is compatible with. I spent a few hours scouring all the service manuals for TDS7K, TDS7KB, CSAx compiling references but am still without a clue what many of these parts belong to
672-1592-02
672-1686-61 //TDS7154B
672-1694-55 //TDS7154
665-1686-10 //TDS7154B
672-5276-00
672-5276-54
672-5276-01
672-5276-52
671-5337-00
I've received several listings of Acq board PNs/models I'll list here for other people looking for correlations or substitute boards:
672-1595-02 //TDS7404
672-1694-55 //TDS7404
672-1686-01 //CSA7404
665-1686-02 //TDS7404B
679-6477-01 //TDS7404B
672-1686-01 //TDS7404B
672-1718-11 //TDS7254B
665-1718-11 //TDS7254B
679-5673-11 //TDS7254B
679-5476-11 //CSA7404B
655-1732-11 //CSA7404B
It seems there are lots of the 672-5276 parts on the market, I would assume this belongs to something popular. Alltest (the ebay vendor) doesn't have the donor instrument information [other than that these are for TDS7xxxxy], so I am hoping to figure this out online. I know how to perform a board ID override and have SN/KEY info for most of the TDS7k, TDS7kB, CSA models. It would be nice to upgrade to 4GHz BW, but I'd be happy with just having my 7254B back in service.
Can anyone help? The primary unknowns are 672-5276, 671-5337, 672-1592. What does the suffix mean (appears to be a version or similar)? Any ideas of other service manuals to examine?
Then there is the question of whether I will even be able to swap a new acquisition board in, even if I found the exact replacement part. Will the scope be able to regenerate its own CAL info or will I have a useless piece of hardware anyway?
Thanks!