UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Argus25 · 13th Aug 2018, 6:06 am

Jeremy,
Regarding your post #60, that is really interesting, Whenever I have added resistance in series with a signal feed in RF circuitry (or any signal circuit)it has never created an HF peak that I have detected and has always seemed to create an LPF effect. Mind you I have not tried it in the probe application discussed with 50R cable and probing 50R systems and also I have no test gear that could detect a peak over 1GHz, so the capacitance of the resistor itself has seemed less dominant that the LFP effect of the added resistance and the capacitance it feeds. But now I know this effect exists I will be on the lookout for it and try to observe it, Thanks.
(RW- I like the idea of a small sleeve around the resistor to flatten the response at the high end, I'm going to make a probe)

13th Aug 2018, 6:06 am	#63
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: Back terminated cable? Jeremy, Regarding your post #60, that is really interesting, Whenever I have added resistance in series with a signal feed in RF circuitry (or any signal circuit)it has never created an HF peak that I have detected and has always seemed to create an LPF effect. Mind you I have not tried it in the probe application discussed with 50R cable and probing 50R systems and also I have no test gear that could detect a peak over 1GHz, so the capacitance of the resistor itself has seemed less dominant that the LFP effect of the added resistance and the capacitance it feeds. But now I know this effect exists I will be on the lookout for it and try to observe it, Thanks. (RW- I like the idea of a small sleeve around the resistor to flatten the response at the high end, I'm going to make a probe)