VHF 20B
- Provides AM voice communication in the frequency range from 116.00-151.975 MHz
- Optional bandpasses available of more or less 8 kHz or more or less 15 kHz
- Solid state transceiver
- Typically used with either CTL-20 digital control or 313N-5 series analog controls
- Composed of subassemblies that mount on a central frame
- Similar to VHF-20A Comm Transceiver but includes extended range to 151.975 MHz
|
DIMENSIONS |
3.750"W x 3.50"H x 13.9"L |
|
WEIGHT |
5.6 lbs |
|
TEMPERATURE RANGE |
-65 to 131°C |
|
ALTITUDE |
up to 55 000 feet |
|
SHOCK |
6 g for 11 ms, operating |
|
FREQUENCY RANGE |
118.000 to 151.975 MHz |
|
FREQUENCY STABILITY |
more or less 0.0015% |
|
CHANNEL SPACING |
25 kHz |
|
FREQUENCY CONTROL |
2-out-of-5, in accordance with ARINC 410 |
|
CHANNEL CHANGE TIME |
Less than 50 ms |
|
TRANSMIT-RECEIVE INTERVAL |
Less than 50 ms |
|
RADIATED RFI |
Meets RTCA Paper DO-138, DO-109, DO-110 |
|
RF POWER OUTPUT |
20W nominal; 16W minimum |
|
OUTPUT IMPEDANCE |
52 ohms, unbalanced |
|
HARMONIC CONTENT |
60 dB down from carrier minimum |
|
SPURIOUS CONTENT |
90 dB from carrier minimum |
|
MODULATION CAPABILITY |
90% amplitude modulation |
|
MODULATOR INPUT |
Carbon mic input 0.125 V adjustable, 150 ohms |
|
SIDETONE OUTPUT |
100mW into 600 ohms with 90% modulation |
|
DUTY CYCLE |
1-minute transmit; 4-minute receive |
|
NOISE LEVEL |
50 dB below 85% modulation at 1000 Hz |
|
AUDIO RESPONSE |
6dB variation from 300 to 2500 Hz |
|
AUDIO DISTORTION |
15% max, at 85% modualtion |
|
RECEIVER SENSITIVITY |
6 dB (signal noise)/noise for 3-uV signal; 30 dB (signal noise)/noise for 100-uV signal |
|
RECEIVER SELECTIVITY |
6 db= about 8 kHz min (for -001 unit), 60 db= about17 kHz max (for -001 unit); 6db= about 15 kHz min (for -002 unit), 60 dB= about 35 kHz min (for -002 unit) |
|
AGC RANGE |
Maximum 3dB variation, 5 to 200,000 uV |
|
RECEIVER AUDIO OUTPUT |
100 mW into 600 ohms, balanced |
|
RECEIVER AUDIO RESPONSE |
6-dB variation from 300 to 2500 Hz, 1000-Hz reference |
|
RECEIVER AUDIO DISTORTION |
7% max, 30% modulated signal |
|
RELATED DOCUMENTS |
DO-138, Env Category AD/A/JNG/AAAEXXXXX; TSO C37b and C38b, class 1, FCC rules and regulations, parts 15 and 87 |
| PART NUMBER | DESCRIPTION |
|
622-1334-001 |
116.000-151.975 frequency range with about 8 kHz IF bandpass filtering and is compatible with about 8 kHz offset carrier systems |
|
622-1334-002 |
116.000-151.975 frequency range with about 15 kHz IF bandpass filtering and is compatible with about 15 kHz offset carrier systems |