The Telewave TWPC-0305-1 Bandpass Cavity Filter 30-40 MHz, is 5” diameter, ¼-wavelength, high “Q” bandpass cavity filter with superior selectivity. Bandpass cavities reject all frequencies outside a narrow pass band. These cavities reduce transmitter sideband noise, and also protect receivers against desensitization.
The TWPC-0305-1 covers 30–40 MHz. The tuning range of these cavities is approximately ±2.5 Mhz from center frequency as built. All cavities are tuned to specified frequencies prior to shipping. No further adjustments should be required. The positive locking mechanism allows for quick field re-tuning if frequency changes become necessary.
These cavities feature calibrated adjustable coupling, so that insertion loss can be easily set from 0.5 dB to 2 dB or more with corresponding increases in selectivity. This allows cavity response to be optimized for any operating environment. Excellent frequency stability is achieved by the use of a specially machined compensator and Invar rod. The pass frequency is temperature stable from -30°C to +70°C. Ground loop technology places the center pin of each coupling loop at DC ground potential.
Heavy duty materials are used throughout each cavity to insure high performance and long life. Cavity top plates are machined from 1/4-inch aluminum, and are heliarc welded to the cavity body at the high current point for improved conductivity and strength. This allows Telewave cavities to handle up to 350 watts, depending on insertion loss.
Rigid foam inserts support the tuner assembly allowing vertical or horizontal mounting. Similar metals and alodined aluminum help prevent galvanic corrosion. Silver plated tuners and beryllium copper finger stock provide non-corrosive low loss contact, and ensure reliable, long-term performance.