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Argus25 · 14th Aug 2018, 6:55 am

Jeremy,

My top Tek generator only goes to 1GHz and I have used it to calibrate my 2465B 400Mhz bandwidth scopes with a recommended 50R Tek cable which is a Tek part.

The 2465B has a 50R termination at its input. Also, as part of the calibration process in line (male to female ) attenuators are used. I didn't have any professional ones and they were pretty expensive (seemed ridiculous) so I made some using 1/8w sized small resistors and some donor housings, a photo of them is on page 26-27 of this article:

http://worldphaco.com/uploads/TEKTRO...THE_DS1225.pdf

But now I wonder if they might have impedance bumps in them, the trouble is I could only test them up to about 500MHz and they seemed OK.

But now I wonder if they should have had compensation capacitors in them. I wonder if the professional versions do ? Or do you think at the frequencies I have been using them < 500MHz, that the response would be unlikely to have any significant peak ?
Thanks, Hugo.

14th Aug 2018, 6:55 am	#65
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: Back terminated cable? Jeremy, My top Tek generator only goes to 1GHz and I have used it to calibrate my 2465B 400Mhz bandwidth scopes with a recommended 50R Tek cable which is a Tek part. The 2465B has a 50R termination at its input. Also, as part of the calibration process in line (male to female ) attenuators are used. I didn't have any professional ones and they were pretty expensive (seemed ridiculous) so I made some using 1/8w sized small resistors and some donor housings, a photo of them is on page 26-27 of this article: http://worldphaco.com/uploads/TEKTRO...THE_DS1225.pdf But now I wonder if they might have impedance bumps in them, the trouble is I could only test them up to about 500MHz and they seemed OK. But now I wonder if they should have had compensation capacitors in them. I wonder if the professional versions do ? Or do you think at the frequencies I have been using them < 500MHz, that the response would be unlikely to have any significant peak ? Thanks, Hugo.