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another possibility is to inject say, a 1 MHz signal (modulated if you can) into the cable at one end. Run a transistor radio tuned to 1 Mhz down the cable. You may pick up leakage. There are similar

Yes, velocity of propagation for the cable, varies with cable type and impedance. Harvey

The 1502 (not a/b/c) certainly has a tunnel diode in it for the main generator. It is difficult to impossible to get ahold of when damaged (and it damages easily since it's right across the input). If

It would be help full to know how long the cable is and how close to the problem you need to get

As Stefan said, how fast a step pulse you need and how much scope bandwidth you need both depend on how much resolution you need. Do you happen to have sampling plug-in set for your 7000 series

Thanks. Does the propagation time depend on the coax type? i don't have the parts to build the circuit right now - could I use the mainframe's pulse generator?

i probably only need to be within a meter or two.

Hi Damien, The faster the edge of the pulse the finer the discontinuity you can resolve. Light travels 299,792,458 m/Sec in free space but in a cable it goes slower at about 66% to 70% of the speed in

Since this is with respect to coax, it probably won't work very well; however, I found that an inexpensive little cable tracker (I got mine at Harbor Freight) is quite useful for finding breaks in

If you have access to both ends, you can just use capacitance measurement if the center conductor is open - not shorted. Just disconnect both ends so there's no load shunting it, check for DC

Well, light in free space goes at about 30cm per nanosecond. It will go somewhat slower in the coax, but to locate the break to 3cm accuracy you will need a pulse rise time of about 100ps, or less.

Depending on the length you need a reasonably fast pulse, there are example circuits on the web that use standard logic drivers (extra fast AC stuff I believe) with a bunch of outputs tied together.

I will be selling or parting out this 465, and a 464. Anyone who wants them or parts should contact me NOW via PM or email. Keith Ostertag stuff@...

Hi everyone, I have a DOCSIS 3 150 Mbps cable modem which just stopped working after a substantial storm (i replaced it to make sure). Apparently the cable is broken. While I'm waiting for the

Yeah, I rewound to watch this again. I don't think he was making contact, as you see the voltage he measures spike to ~1.5V with only one of the probes touching, and basically wandered around that

I'm working on a 2215 with a current limit board. The HV section is very clean so Im questioning if the CRT is actually bad. I know about the CRT over voltage issues with this scope. Here is a picture

I too struggled to watch the video, a bit too laconic for my taste I guess. I was somewhat put off by the ham-fisted removal of the bridge rectifier and the filter cap. Damaging the PCB because you

(continued) Well, unless it happens to be say +14 V. That's enough for U1524A (+55) but not for U1524B (+15), see also post by Dave Hills.

May I disagree with the end of the sentence? The only common diagnosis so far is that +55 and +110 are slightly low and that +15, +5 and -8 are close to zero. You measured +22.5 V or so after the +15

Hi all, I added a picture of a set of feet how they are supposed to look like. Pictures can be found here: /g/TekScopes/album?id=61275 I looked at both Qservice and Sphere, but they