| Fixed EQ Selection
Chart |
| Variable equalizers for 450 MHz have insertions
losses from 1.5 dB to 2.6 dB, based on model type. The SEP-454ST has the highest
insertion loss. Since this is the EQ needed for very long trunk spans, it is very
desirable to use a fixed equalizer with a loss of only 1 dB for these locations. |
| The QLX equalizer is compatible with Jerrold JLX
and BLE line extenders and is available in 550, 750, and 860 MHz series for that
application. Values range from Zero to 24 dB in 2 dB steps, with values below 450
MHz offered up to 30 dB. The higher frequencies are not usable in the SJ
application. A special order 500 MHz QLX is the highest bandwidth which has been
used with SJ-450B Jerrold trunk modules to get the maximum bandwidth from 450 MHz hybrids
in that product. The bandwidth is then limited by the bandwidth of the hybrids
themselves, typically 495 to 500 MHz. Click here to see drawings
showing EQ usage for SJ trunk stations. |
| The chart below has frequencies from 300 to 860
MHz referenced to channel 2 at 55.25 MHz for fixed equalizer
selection. These solutions to the equation on the previous
page will usually get within 1 EQ value for the specific cable slope correction needed
for flat input signals. The chart applies to all fixed EQ styles for any brand of
equipment. The insertion losses for a popular series of fixed equalizers is on this
site. Click here to see the EQ loss curves. |
| K factor •> |
0.5674 |
0.5878 |
0.6023 |
0.6271 |
0.6477 |
0.6823 |
0.7277 |
0.7455 |
RF Level
Difference |
Ch. 36
295.25 |
Ch. 41
325.25 |
Ch. 45
349.25 |
Ch. 53
397.25 |
Ch. 61
445.25 |
Ch. 78
547.25 |
Ch. 116
745.25 |
Ch. 134
853.25 |
| 1 dB |
1.76 |
1.70 |
1.66 |
1.59 |
1.54 |
1.47 |
1.37 |
1.34 |
| 2 dB |
3.52 |
3.40 |
3.32 |
3.19 |
3.09 |
2.93 |
2.75 |
2.68 |
| 3 dB |
5.29 |
5.10 |
4.98 |
4.78 |
4.63 |
4.40 |
4.12 |
4.02 |
| 4 dB |
7.05 |
6.80 |
6.64 |
6.38 |
6.18 |
5.86 |
5.50 |
5.37 |
| 5 dB |
8.81 |
8.51 |
8.30 |
7.97 |
7.72 |
7.33 |
6.87 |
6.71 |
| 6 dB |
10.57 |
10.21 |
9.96 |
9.57 |
9.26 |
8.79 |
8.24 |
8.05 |
| 7 dB |
12.34 |
11.91 |
11.62 |
11.16 |
10.81 |
10.26 |
9.62 |
9.39 |
| 8 dB |
14.10 |
13.61 |
13.28 |
12.76 |
12.35 |
11.73 |
10.99 |
10.73 |
| 9 dB |
15.86 |
15.31 |
14.94 |
14.35 |
13.89 |
13.19 |
12.37 |
12.07 |
| 10 dB |
17.62 |
17.01 |
16.60 |
15.95 |
15.44 |
14.66 |
1374 |
13.41 |
| 11 dB |
19.39 |
18.71 |
18.26 |
17.54 |
16.98 |
16.12 |
15.12 |
14.75 |
| 12 dB |
21.15 |
20.41 |
19.92 |
19.14 |
18.53 |
17.59 |
16.49 |
16.10 |
| 13 dB |
22.91 |
22.11 |
21.59 |
20.73 |
20.07 |
19.05 |
17.86 |
17.44 |
| 14 dB |
24.67 |
23.82 |
23.25 |
22.33 |
21.61 |
20.52 |
19.24 |
18.78 |
| 15 dB |
26.44 |
25.52 |
24.91 |
23.92 |
23.16 |
21.99 |
20.61 |
20.12 |
| 16 dB |
28.20 |
27.22 |
26.57 |
25.52 |
24.70 |
23.45 |
21.99 |
21.46 |
|