Inhaltsverzeichnis
ULPE
VHF/UHF direction finder ULPE, Rohde & Schwarz PA004/CH; manufactured by Rohde & Schwarz, Munich.
The PA004/CH UHF direction finding system from Rohde & Schwarz was evaluated around 1970 for the EKF of the Swiss Air Force / Air Defence and two units were purchased for the Air Force; the systems remained in operation in 1975/88 and were liquidated in 1999.
Only the succeeding improved variant PA003/CH was acquired in larger numbers and was used in P-728 and later adapted systems.
Technical data
- Principle]]: VHF/UHF direction finder Rohde & Schwarz PA004/CH
- Frequency range: Station type I 30 - 1300 MHz; station type II with EZFU 30 - 2700 MHz; analogue display
Power supply
- Mains operation]]: 220 V
Dimensions
Accessories
System material
The system consists of the VHF-UHF monitoring receiver ESUM with the HF part adapter to the ESUM, in which the various frequency tuners are installed and can be selected from the main receiver. The Station type I thus covers the frequencies from 30 - 1300 MHz.
In Station type II, the UHF receiver EZFU is also contained, as a way to extend the frequency coverage up to 2700 MHz.
The frequency is displayed digitally with the receiver frequency counter FET3 using Nixie tubes.
The signals can be measured and analysed in the EZF analyser and a certain band sections can be monitored as with a panoramic viewing device.
From the direction finding display unit PV003, which was later also part of the regular P-728 direction finder, the bearing of the signal can be read from a digital display once the bearing ruler has been aligned.
The power supply for the various components is also integrated in the PR004 control unit.
The AP805 DF antenna with a logarithmic-periodic UHF antenna and additional VHF antennas proved to be the weak point of the system. Installation at the high-altitude sites showed that the antenna was too heavy and too susceptible to icing and the effects of the weather.
Technical principle
Tube assembly
Development
The PA004 direction finder was developed by Rohde & Schwarz from 1970 onwards.
Use
From the Rohde & Schwarz PA004/CH, two systems (one each of station type I 30 - 1300 MHz and station type II with additional EZFU 30 - 2700 MHz) were procured for the EKF Air Force around 1970 at a unit price of DM 275,415 and installed at mountain sites.
It remained in operation from 1975 to 1988 and was liquidated in 1999.
In the original configuration with the AP 805 UHF antenna, the rotating antenna system proved to be too heavy. Rohde & Schwarz developed an improved system, which was introduced by the Air Force as the P-728 in 1980, original Rohde & Schwarz designation was PA003/CH.