Item Details:
Telewave TWPC-3505 Bandpass Cavity Filters
Telewave TWPC-3505-1, 3505-2, and 3505-3 are 5" diameter, ¼-wave high-Q bandpass cavity filters with superior selectivity. They pass a narrow 300–400 MHz band, rejecting all else to suppress transmitter sideband noise and protect receivers from desensitization.
Factory-tuned; no adjustments needed. Positive locking enables quick field retuning. Adjustable coupling sets insertion loss from 0.5 dB to >2 dB for optimized selectivity. The 3505-2 and 3505-3 deliver higher selectivity with minimal loss in crowded sites. Combine cavities for wider passbands; rails included.
Temperature-stable (-30°C to +70°C) via machined compensator and Invar rod. Ground Loop tech grounds loop centers for lightning protection and noise reduction.
Rugged build: ¼" aluminum top plates heliarc-welded at high-current points; handles up to 350 W (loss-dependent). Alodined aluminum, silver-plated tuners, and beryllium copper contacts prevent corrosion and ensure low-loss, reliable performance.
Specifications:
| Tuning range: |
200-300 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: |
¼ 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 18 inch (13 x 46 cm) |
| Connectors: |
N or UHF female (opt.) |
| Finish: |
Gray acrylic enamel |