Narrow-Band Bandpass Graphs:
NF7-4.5 (audio) , VF7- (180) , NF7-76 HQ,
and NF7-721.25 HQ
Graph 1 : NF7- 4.5 ( audio ) Fixed Narrow Bandpass
NF7-4.5: Bandpass designed to pass TV baseband audio
- Audio passband loss: < 3.5 dB
passes baseband audio at 4.5 MHz and rejects the video band by > 30dB (Mkr 2) - 40dB rejection from +/-1.5 MHz Fc
- Designed for RF modulator's audio input, prevent audio interference on video
Mkr | Freq (MHz) | Attn (dB) |
1 | 4.500 | -3.434 |
2 | 4.200 | -34.878 |
3 | 6.000 | -45.067 |
Graph 2: VF7- (180) Tunable Bandpass
VF7-180: Pre-tuned passband at 180 MHz, with > 15 dB rejection of frequencies ± 3 MHz from Fc.
- Passband loss (Fc) is < 3dB
- Stopband: >15 dB ( Mkr 2 & 3 )
- Rejection: > 40dB from ± 15 MHz Fc
- Tunable range: 170 MHz to 190 MHz
Mkr | Freq (MHz) | Attn (dB) |
1 Fc | 180.00 | -2.727 |
2 | 177.00 | -15.778 |
3 | 183.00 | -15.667 |
4 | 166.00 | -41.033 |
5 | 192.00 | -40.198 |
Graph 3: NF7-76 HQ Fixed Bandpass
NF7-76 HQ: Very narrow Data Carrier Bandpass
- Data carrier bandpass between chs 4 and 5
- Pass 76 MHz - passband < .75 MHz
- Stopband: >20 dB ± 1.5 MHz Fc
- Rejection: > 40dB from ± 5 MHz Fc
- Factory retunable
Mkr | Freq (MHz) | Attn (dB) |
1 Fc | 76.000 | -3.186 |
2 | 74.500 | -22.038 |
3 | 77.500 | -22.068 |
4 | 71.000 | -44.029 |
5 | 81.000 | -41.059 |
Graph 4: NF7-721.25 HQ Fixed Narrow Bandpass
NF7-721.25 HQ: CATV Channel 112 video bandpass
- Pass mainly 721.25 MHz (ch.112 video carrier) for CATV system measurements
- Stopband: > 20 dB ± 5 MHz Fc
- Rejection: > 40dB ± 20 MHz Fc (approx)
- Ch.112 audio carrier (725.75) is attenuated by 20 dB
Mkr | Freq (MHz) | Attn (dB) |
1 Fc | 721.25 | -4.427 |
2 | 716.25 | -20.073 |
3 | 726.25 | -21.600 |
4 | 703.00 | -40.825 |
5 | 737.00 | -41.349 |