Item Details:
Telewave TWPC-4505 Bandpass Cavity Filters
Telewave TWPC-4505-1, -2, and -3 are 5” diameter, ¾-wavelength high-Q bandpass cavity filters with excellent selectivity. They pass a narrow frequency band (400-512 MHz) while rejecting others, suppressing transmitter sideband noise and preventing receiver desensitization.
Factory-tuned with a positive locking mechanism for easy field retuning if needed. Adjustable coupling sets insertion loss from 0.5 dB to 2+ dB for optimized selectivity. The -2 and -3 models offer superior performance with minimal loss at crowded sites; multiple units can widen the passband. Mounting rails included for multi-cavity setups.
Temperature-stable (-30°C to +70°C) via machined compensator and Invar rod. Ground Loop design grounds coupling loops at DC for lightning protection and noise reduction.
Built for durability: ¼-inch aluminum top plates heliarc-welded to body, handling up to 350 W (depending on loss). Rigid foam supports tuner for any orientation; similar metals and alodined finish prevent corrosion. Silver-plated tuners and beryllium copper contacts ensure low-loss, reliable long-term operation.
Specifications:
| Tuning range: |
400-512 MHz |
| Nominal impedance: |
50 ohms |
| VSWR at resonance (max): |
1.5:1 |
| Input power (max) vs. insertion loss: |
0.5 dB - 350 watts 1 dB - 250 watts 2 dB - 150 watts |
| Temperature range: |
-22°F to +158°F -30°C to +70°C |
| Cavity electrical length: |
¾ wavelength |
| Outer conductor, end plates: |
6061-T6 aluminum |
| Inner conductor, coupling loops: |
Silver plated copper |
| Tuning rod: |
Invar |
| Contactors, fingerstock: |
Beryllium copper |
| Cavity dimensions (Diam. x H): |
5 x 23.5 inch (13 x 60 cm) |
| Connectors: |
N or UHF female (opt.) |
| Finish: |
Gray acrylic enamel |