Author Topic: Teardown : Tektronix TCA-1MEG high-impedance amplifier for TekConnect  (Read 2763 times)

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Offline TiN

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High-end Tektronix (series 7000/70000) have proprietary TekConnect HF inputs, which accept only 50 ohm inputs.
This limits usage of such scopes only to special (read - expensive) TekConnect active probes.

Also using DIY is not a simple forward path either, as even simple passive adapter from TekConnect to BNC or SMA (TCA-BNC, TNC-SMA) cost few hundreds USD on ebay easy!

If you want use 1 Meg input impedance options even more limited, with Tek's offering of TCA-1MEG amplifier, which costs ~500$ used.

Was lucky to get one of these relatively cheap, so here's a teardown (article per image link):

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Offline MSS

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Re: Teardown : Tektronix TCA-1MEG high-impedance amplifier for TekConnect
« Reply #1 on: March 16, 2020, 07:37:50 pm »
Nice work! I want to make such probe adaper. Have you any ideas about it? Have you trace the connection between scope and that "blac-box" ic with heat sink on it?
 

Offline David Hess

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Re: Teardown : Tektronix TCA-1MEG high-impedance amplifier for TekConnect
« Reply #2 on: March 17, 2020, 08:51:13 pm »
In its basic form it comes down to a high impedance buffer stage followed by a x2 amplifier to drive a double termination which is how an active probe could work.  But usually an active probe would do away with the amplifier and use x10 total attenuation instead.  High impedance oscilloscope input circuits work the same way so there is another source of examples.
 
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Offline charlyd

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i  bought this TCA-1MEG adapter and after connecting
it gives "fail".  does any have experience with these failed
adapters ? i saw it was a 24C16 behind a expander chip.
can it be a corrupt content ? or ?

the seller didn t want to take it back  |O
help or donor unit wanted

i will open up new post.
« Last Edit: May 07, 2021, 03:39:29 pm by charlyd »
 


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