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Tektronix ADA400a differential amplifier

I have this tektronix ada400a differential amplifier, bought it long ago, and it only gathers dust now.
The ada400a gets it power from its special bnc connector, and can under normal circumstances only be used with tektronix oscilloscope,
But this one is hacked, i installed a cable to the box so it can be fed its required +/÷15 volt and the +5 volt, from external source, bench psu or dedicated psu.
Nothing else is tampered with, the special bnc connector is still Connected, but the pins for psu removed, I have them somewhere, so it can be brought back to standard, but this way it's very versatile, and accepts all oscilloscope.
Asking price 600 euro. New price is roughly 2700 euro
Ps. This guy in the link gave me the idea to hack it, and did it like him, wanted to use jan diddens silent switchers and power it from usb.


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And today another 100 euros off...
Attached is a photo of the item in question, notice the red cable, that's the external psu cable, it's a high current charge cable for cell phones, perfect for this.
Item is in very nice condition, no Marks anywhere


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