Inhaltsverzeichnis
Wireless Set No. 33
Used by the Royal Signal Corps.
The British Wireless Set No.33 was a successor of the Wireless Set No.12 from 1941/2 with its high-performance power amplifier in the same cabinet.
The set includes a power supply unit with almost the same dimensions and weight, so it can be used as a vehicle or fixed station.
Technical data
- Frequency range: 4 x SW (1.2 - 17.5 MHz)
- Frequency display: Analogue dial
- Frequency memory: none
Power supply
- Mains power supply unit
- 2 kVA generator for mobile operation
Dimensions
- 584 x 635 x 406 mm, weight 79.5 kg
Accessories
Operation
The Wireless Set No.33 is very similar to a Wireless Set No.12 with its matching high-performance power amplifier installed in a common cabinet. With a size of 58.4 x 63.5 x 40.6 cm and a weight of 79.5 kg, the station is only „portable“ to a limited extent. An R107 or R106 (HRO) was usually used as the matching receiver.
The front panel is divided into two sections, the lower section belongs to the modified Wireless Set No.12, the upper section to the power amplifier.
The oscillator is located at the bottom left of the transmitter and can either be tuned free-running in four ranges (1.2-2.55 / 2.5-5.3 / 5.2-10.5 / 10-17.5 MHz) in the lower shortwave spectrum or crystal-controlled. In TUNE tuning mode, the commanded frequency is set on the rudimentary dial at the bottom left or, in crystal-controlled fixed frequency mode, the CRYSTAL TUNING light illuminates when the crystal and oscillator frequencies match. The next step is to tune the buffer stage, select the corresponding range with the switch above the tuning knob and tune from 180 degrees with BUFFER TUNING until the BUFFER TUNING indicator light lights up at maximum, followed by tuning the driver stage. Here, the appropriate range is selected with the switch above the DRIVER TUNING CONTROL knob and tuned to maximum illumination of the DRIVER TUNING indicator light starting from the 180 degree position in a similar way. Finally, the power amplifier is tuned by first setting a minimum anode current with the P.A. tuning control and then gradually increasing the antenna coupling until a maximum antenna power or an antenna current in the P.A. of 250 mA is reached; the approximate position of the corresponding antenna tuning controls can be found in the frequency table. (if you want to operate your W.S.33, you should have a valid amateur radio licence and read the technical manual or the information in L. Meulstee's book).
In comparison with the Fahrbar Leichte Funkstation 40 developed by Zellweger AG in the same period, the English set looks quite archaic, the front panel doesn't have a very uniformly appearence and the frequency reading accuracy is only arbitrary compared to the FL transmitter. The set had been designed in no time at all from 1940 as a replacement for the obsolete W.S. No.2 from the 1930s. As an alternative to the W.S.33, a variant of the Wireless Set. No.12 HP (high power) was developed and during the Second World War the set was replaced by the W.S. No.53.
Technical principle
Components
The set is equipped with tubes.
