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Hi Owen,
Hi Owen, I am using large copper cable and relatively low loss capacitors. I expect the 9 ohms of inductive reactance to cancel out the -9 ohms of capacitive reactance leaving only the sum of the AC (or RF) resistance of the copper and the ac resistance of caps to give me my net impedance. Am I correct up to this point?? I'm trying to take this step by step so I can understand where I've gone wrong.....clearly I must have made an error somewhere. I don't know what the actual ac resistance of the caps is, but I do know the ac resistance of 20 meters of #2/0 copper welding cable is pretty damn low. Yes, the loop is series tuned, so the output is taken on the unconnected capacitor terminal and the unconnected wire end. Rjeloop3 gives estimates my Q at 221 even though it thinks I'm building a parallel tuned loop. But, I think Q is Q, and the Q of both types of loops is the same provided the same materials have been used in both loops. I am (for now) not considering the effects of hooking it to a receiver and/or the transmission line. I confess I have not tried to quantify the actual values of the ac resistance of the copper and have only rough estimates of what the esr of the caps is. I'd be pretty surprised if the dc resistance of the cable is much more than .1 ohms though, so the ac resistance should be a little higher at 60 KHz. Can you estimate what the unloaded Q of the loop is (in round numbers), and if so, can you agree that it might be around 221 (as Reg's software predicts)? Can you estimate what the impedance of the loop is (in round numbers)? Again, do not factor in the receiver input impedance as we aren't sure whether I'll keep it as is or match it's impedance with a preamp and/or toroidal transformer. For the moment, assume the receiver is mounted at the loop (which is a very real possibility since it's fairly small). Thanks for jumping in. T |
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