====== SE-300: Mobile Lightweight Radio Station 40 ====== **Fahrbar Leichte Funkstation 40** (Mobile Light Radio Station 40), **FL40**; manufactured by [[Zellweger, Uster]]. To replace the "Tragbar Schwere Funkstation 18/25" (Heavy portable wireless station 18/25) and the "Fahrbar Leichte Funkenstation 19/25" (Light mobile wireless station 19/25), [[Zellweger]] AG, Uster developed a new wireless station covering the longwave and shortwave band in the years 1938 - 1940. Still according to the doctrine of use from the twenties / thirties, the wireless station was designed on a single axis trailer to be pulled by another vehicle, it got the nickname „vegetables trailer“ from a kind of trailer used by vegetable farmers. If mobile use on a trailer was impossible, for example if the station should be operated in a bunker, a command post or on a hill or mountain top without an access road, the station with the same components was used as [[SE-215|Tragbar Schwere Funkstation]] [[SE-215|TS40]] („Heavy portable station 1940). Nearly all accessories were included, in favour of the troop which had to carry the station, the DF antenna for the receiver and the 10 m telescopic mast was omitted. The entire radio station FL40 is housed in two single axis trailers: one is the "apparatus trailer" with transmitter, receiver and the telescopic antenna mounted on the trailer, the other is the "machine trailer" with a three phase generator driven by a petrol or an electric motor. The generator provides the necessary (plate) voltages, all antenna material is also stored on the trailer. {{:images:se-300-fl40-protzenwagen.jpg?direct&600|SE-300 "Gmüeswägeli"}} ===== Specifications ===== * [[Principle]]: Wireless station with separate [[transmitter]] and [[receiver]] * Receiver **[[E41|E41, all-wave receiver Uster]]**: [[double conversion|single / double conversion]], [[IF]] 70, 465 kHz * Transmitter **[[S-300]]** * [[Modes]]: [[A1|A1 (CW)]], [[A2|A2 (telegraphy)]], [[A3|A3 (AM)]] * [[Frequency Range]]: 190 - 715 kHz; 1.5 - 4.5 MHz * [[Sensitivity]]: [[A3 | AM (A3)]] / [[selectivity]] * [[Output power]]: [[A1]] 100 Watts, [[A3]] 25 Watts ==== Power Supply ==== * Petrol operated or electric motor (220/380 V) to drive a 50 V / 150 Hz three-phase generator. The station was powered by a petrol or by an electric motor coupled to a three phase generator, which provided the necessary 50 V 150 Hz voltage. A rectifier unid was used to generate the plate voltages of 1250 and 300 V for the transmitter and a solid state rectifier to generate the plate voltage of 120 V and heaters voltage of 6 V of the receiver and the accumulator charger. An inverter is used to generate the plate voltage of the receiver [[E41]] from the heaters accumulator power of 6 V, when the generator of the transmitter was not in use, or for remote control of the station. ==== Dimensions ==== {{ :images:se-300-fl40-zwei-protzenwagen.jpg?direct&200|two trailers}} * the apparatus trailer has a weight of 840 kg, the machine trailer with the generator 870 kg ==== Accessories ==== * Longwave antenna: Long wire antenna 50 m between two 10 m masts * Shortwave antenna: 10 m mast antenna or 8 m long wire antenna between two 10 m masts. * Remote Control Unit [[FBG-FL|FBG FL]] ===== Operation ===== [[se-300-stationmaterial|Here]] find an overview of the components of the **Mobile Light Radio Station 40**. ===== Technical Principle ===== The station receiver [[E-601|E41]] is a battery valve all-wave receiver; at frequencies below 12 MHz, it acts as [[single conversion]] set and above 12 MHz as [[double conversion]] superhet; the frequency band selection is done with plug-in coil sets, similar to those found in the [[E-610|HRO]]. The matching transmitter [[S-300]] is housed in an almost "portable" metal chest with side flaps for aeration and for the antenna connectors. The transmitter covers longewaves 190-242 / 242-400 / 400-715 kHz and three shortwave ranges 1500-2300 / 2300-3300 / 3300-4500 kHz, a calibration crystal is used to calibrate the transmitter on 4000 kHz. ==== Valve Layout ==== Refer to the pages of the components. ==== Development ==== In 1938, there was an invitation of tenders to develop a "mobile lightweight" radio station as a replacement for the "Mobile light radio station 19". There were outlines of sets from C. Lorenz AG and Telefunken Zurich AG; but [[Zellweger, Uster]] submitted a suggestion matching all requirements, still mounted as required on a single axis trailer, prototypes of the set had a very good echo and after great effort the first production badge was delivered to the troops already in 1940/1. The newly developed components like receiver and transmitter were not only used as FL40 ("so-called Gmüeswägeli"), but electronically identical also as [[SE-215|TS40]] ("Portable Heavy Station 40"), as KL43 ([[SE-218|G-Station]] to replace the short-longwave station Telefunken and it's all-wave receiver "Uster" / [[E41]] was used as standard receiver in the high power stations until its replacement by the [[E-627]]. 98 units of the "Mobile Light Stations 40" were ordered, in 1942 the station was equipped with additional antennas (L and T antenna) for ionospheric communication. The station was replaced by the SSB station [[SE-222]] in 1961 and all station equipment was liquidated in 1971/72. ==== Field Use ==== The 98 station were delivered 1939/43 and were used for command communication until 1958, the equipment was liquidated in 1971/72. {{gallery>:images?se-300*.jpg&0&80x80&lightbox&showtitle&titlesort}} ===== Technical Information ===== * {{ :manuals:se-215-se-300-die-fahrbar-leichte-funkstation-regl-178.pdf |Die fahrbar leichte und tragbar schwere Funkstation, Techn. Reglement Nr. 178, prov. 1943}} * {{ :manuals:se-215-se300-funkstation.pdf |Die Funkstationen SE-300 und SE-215 (FL40 und TS40) mit Fernbetriebsgerät, Regl. 58.113d, 1958}} * {{ :manuals:se-215-se300-fernbetriebsgeraet.pdf |SE-300 und SE-215: Das Fernbetriebsgerät, Regl. 58.114d, 1951}} * {{ :manuals:se-300-fl40-anleitung-fuer-funk-reparateure.pdf |SE-300: Techn. Anleitungen für Funk-Reparateure}} * {{ :manuals:se-300-fl40-beschreibung.pdf |SE-300: FL 40, Beschreibung, Zellweger AG, 1942}} * {{ :manuals:se-300-fl40-manual.pdf |SE-300: FL 40, Beschreibung, Zellweger AG}} * {{ :manuals:se-300-fl40-ts40-manual.pdf |SE-300: FL 40 / TS 40, Beschreibung, Zellweger AG}} ==== Additional Information ==== * [[http://armyradio.ch/radio-d/se-300.htm|SE-300 on www.armyradio.ch]] * [[https://www.hamfu.ch/de/geraete/geraet.php?id=47|SE-300 on Hamfu Website]] * [[https://www.radiomuseum.org/r/zellweger_sender_se300se_30.html|SE-300 on www.radiomuseum.org]]