I wholly agree with Tom Gardner¡¯s comments. Playing with the BNC connector may be converting the 1502 into a parts unit. Besides, the 1502 was designed for a specific purpose and Tek engineers designed it to those criteria. Trying to improve its performance to a higher level that I don¡¯t quite understand why you may be trying to make a dragster out of a utility vehicle. That¡¯s why Tek came out with the 1503 to improve measurement specifications and protect the pulser from ESD.
I have located faults in several mile runs of telco cables that transitioned between aerial and buried with accuracy to a foot or few to the fault using a Tek 013-0169-00 balanced output isolation transformer connected to the output of a 1503 TDR.
I have both 1502s and 1503¡¯s. I seldom use the 1502s. I also have a couple of Cabletron TDR5000 TDRs that are unbelievably quite accurate even though the Cabletron company simply made them out of modified old Philips PMxxxx series oscilloscopes. But all of these are used on simple wiring, not coax. I use FFT DTF for very accurate coax cable fault location.
Greg
