How to determine the frequecy rage limits of a line tuner.
How to determine the frequecy rage limits of a line tuner.
(OP)
How can I determine the frequency range limits of a line tuner to make sure that the low and high frequencies I picked will work for a power line carrier application?
The line tuner is Trench, model A9508, bandpass, the frequencies I would like to use are:
DCB 129kHz
TTR 74kHz and 74.5kHz
TTT 133kHz and 133.5kHz
If I know the capacitance of the CCVT, how can I figure out if the frequencies I picked will work?
Thanks for the help.
The line tuner is Trench, model A9508, bandpass, the frequencies I would like to use are:
DCB 129kHz
TTR 74kHz and 74.5kHz
TTT 133kHz and 133.5kHz
If I know the capacitance of the CCVT, how can I figure out if the frequencies I picked will work?
Thanks for the help.






RE: How to determine the frequecy rage limits of a line tuner.
If memory serves,
BW = 2*pi*(GMF^2)*Rl*CC'*k
BW = bandwidth
GMF = geometric mean frequency = for simplicity it normally works just to take the middle frequency between your lowest and highest frequencies used. So in your case GMF~104kHz.
Rl = characteristic impedance of the transmission line
CC' = effective coupling capacitance in uF = coupling capacitance of the CCVT in series with the blocking capacitor of the line tuner (normally this is 10 or 15 uF for a 2nd order BP line tuner).
k = is a factor based on the maximum return loss limit for defining the band-width. This would be in the Trench literature too. I believe a 10 dB return loss limit is close to k = 1 (something like 0.97).
RE: How to determine the frequecy rage limits of a line tuner.
The roll off of a line tuner is defined by the expected impedance loss. And how sharp the roll off is will depend on the designed Q.
Better to look it up in the manual.
Since the line tuner works with the Coupling capacitor, that will also make a difference.
RE: How to determine the frequecy rage limits of a line tuner.
RE: How to determine the frequecy rage limits of a line tuner.
Thanks,
RE: How to determine the frequecy rage limits of a line tuner.
RE: How to determine the frequecy rage limits of a line tuner.