pardon me if i just jump right in;With the Pulser, don't you have to know where the path of the wire is first? I looked at something like that when I purchased the 521, but found out I had to first locate and mark the path of the wire run before I could go down the line with the fault locator. With the 521, I just go down the line and test voltage once I have a suspicion of where the cut is. Actually, once I tone the path I can usually figure out where the cut is just by using logical thinking. In other words, if your toning the wire and see that it's path runs across what looks like a freshly planted shrub or flower, that is usually the first place to look. I do have one question though for anyone that knows: Do you have to turn the power off at the transformer in order to use the 521? Sometimes it's easier to hook the machine up at the end of the run and work your way back to the trans. I always disconnect the trans, but it would be nice if I could just leave the juice flowing so I could check the voltage without have to go back to the trans to turn it back on.
when using a fault locator/ A-frame, you do have to know the wire path, that can first be located by a wire tracer 521/pro-700, 508s, 501, pro-290, pro-871 ect. or you can, with some practice, use the pulser/gfl-3000 to locate the the wire path. in order to locate the wire path with a pulser/gfl-3000 you connect the transmitter, walk about 20' away from the transmitter and place the a-frame at about a 45 degree angle towards the suspected location of the wire path, follow the kick until it reverses. by zig-zaging you can get close enough to mark the path. it's not as difficult as it sounds and after doing it a few times it's fairly fast.
without the fault finder you can be pretty accurate with the 521/pro-700 by using the 6" offset method suggested in the 521 section of the pei link below.
yes you have to turn the transformer off, here is a link for the tempo 521 manual, it includes the 501, 508, 528, 521 and pulser operating instructions;
these instructions and tips also work for the pro-700 and so on.
in regards to your statement about the ease of voltage testing with the transformer on, we are using the 521/pro-700 transmitter to test voltage drop on 2-wire irrigation systems.
i'm assuming that you use a leakage clamp meter, i just bought a pro-92 which i have really gotten to like.
another tool that i have been using to troubleshoot with is the TDR, with a TDR i am able to diagnose the condition of the wire path and as a plus it will give me the distance to a compromise. TDRs however cannot be connected to a live system but it will see the distance to a broken wire or compromise. i have found the TDR to be one of the most important tools i have ever used.