1705
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The Tektronix 1705A is a spectrum monitor designed primarily for locating Ku or C-Band satellites and monitoring their signals.
It operates by using LNB down converters to the L-Band (950 MHz to 1.8 GHz), and monitoring up link transmissions utilizing an upconverter to the 70 MHz IF (45 MHz to 100 MHz). The resolution bandwidths 10 kHz and 300 kHz provides measurement resolution proportional to the frequency accuracy or span.
The CRT graticule can be lit by setting an internal jumper. The front-panel switch settings can be saved to NVRAM. The user interface has on-screen frequency readout as well as setup menus. The L-Band readout may be reconfigured to display a satellite frequency in the range of 0.9 GHz to 20 GHz.
Key Specifications
| Frequency | L-Band: 950 MHz to 1.8 GHz; 70 MHz band: 45 MHz to 100 MHz |
|---|---|
| Frequency Span | L-Band: Full, 10 MHz/div, 1 MHz/div, and 10 kHz/div; 70 MHz: Full, 1 MHz/div, and 100 kHz/div |
| Resolution Bandwidth | –6 dB bandwidth selections 300 kHz / 10 kHz |
| RF Input | 75 Ω |
| Maximum Safe Input Power | L-Band: –30 dBm; 70 MHz: –20 dBm |
| Minimum Signal Input | –80 dBm |
| Video Filter | Reduces Video Bandwidth to ≈ 10 kHz |
| RF Attenuator Range | No built-in internal attenuation. Apply an external attenuator to keep the maximum safe input power below the rating listed above |
| Sweep Speed | 20 ms to 200 ms, variable |
| Display | 80 mm × 100 mm (3" × 4") CRT, P31 (Opt. 74: White Phosphor) |
| Weight | Standard accessories: 3.8 kg (8.5 lbs) |
| Power | 90 − 250 VAC, 48 to 66 Hz, 35 W |
Rear panel:
- L-BAND INPUT, F connector: 900 – 2000 MHz down-converted from L-Band RF by a low-noise block converter (LNB)
- LNB POWER switch enables or disables an 18 V supply for the LNB at the L-band input
- 70 MHz INPUT BNC connector (for 45 MHz – 100 MHz RF)
