In the Yugoslav People's Army to the radio devices that have worked in the HF (high frequency) band were setting up a call on a tactical, operational and strategic level. Mostly was working with SSB (single-sideband) and CW (continuous-wave) modulation, and less with AM (amplitude modulation). In the radio connection between the higher units was dominated the RTTY (radioteletype) modulation. Output power of transmitter was ranged from 1 - 10 W for links on small and medium distance, to a few kilowatts for links to a large distance.
HF (high frequency) have frequencies from 3 MHz to 30 MHz. The characteristic of this frequency range is that electromagnetic radiation is divided into ground-wave and sky-wave. The ground wave provides a link on the short distance because is similar with VHF waves, search radio horizon.
The second, much more, interesting component (sky wave) wound and one part refuse from the earth ionosphere and as that turned back can make a connection with the participant on the other part of the world. On the other hand, this communication are very easy for interception and disturb. There is no radio operator who is working on HF range that didnt felt that, especially in the night. This is brought to , not so often, link could not upkeep in the required time. Because of these reasons "great" armies are almost completely left this band and passed to the satellite links.
In the introductory page, we emphasize that we will not describe the radio devices created before and during World War II, this HF radio receiver, produced in Germany in 1936. however, deserves to be found on this page. Receiver was mass produced for the needs of the German army, and in 1945. on this device was done more modification. (The device described here is a version from 1943.) In the arsenal of Yugoslav Army it was found as war booty in 1945. which is by the first repair in Yugoslav workshops winner had to emphasize with writing on the box:"captured 16962 devices". In Yugoslav Army receiver is used in conjunction with the transmitter or independently. The device was dropped from the fifties of the Yugoslav Army equipment.
Radio receiver TORN Eb was intended for receiving AM telephony and telegraphy (CW) in the frequency range of 0.097 MHz to 7.095 MHz. This frequency range was divided to 8 frequency band that was chosen by the switch a fine set frequency was within continuous. By the construction receiver was super-reaction and in its was built 4 German vacuum tube RV2P800. The first tube was made from 1 VF intensifier, and the other from 2 VF intensifier, third AM detector and the fourth tube was AF intensifier (See reduced electric scheme published in the Bulletin of "Školski centar veze" - School of telecommunication in Yugoslav Army in Belgrade). As in all other super-reaction receiver, receiver sensitivity and selectivity was regulated by the introduction of positive feedback couple that was setting with special button.
The device was put in two metal container and in the top container was receiver, in the lower container was battery, vibrators converter, wire antenna and headphones. Device was powering on from battery voltage of 2 VDC - 0.8 A, over vibrators converter or anode battery of 90 VDC - 10 mA. There was versions in which was changed converter to ensure supply with voltage of 12 V from the installation of vehicle.
Technical Specification: Frequency range: 0.097 MHz - 7.095 MHz; Modes of Operation: AM (amplitude modulation) and CW (continuous-wave); Power Requirements: 2 VDC battery or anode battery 90 VDC; Origin:ex Nazi Germany.
PR-03 "Avala" HF Radio Receiver
This radio receiver in a small series is produced by "Avala" - factory capacitors and electronic devices from Belgrade, probably after the end of the World War II. This factory is not producing military radio devices but is participated in the production of military electronics. For receiver type RP-03, we learn, thanks to photos and descriptions that we got from Mr. Zec Radoslav. To the data was based on visual examination receiver, with the numeration: Series 3 number 13.
Technical Specification: Frequency Range: 500 KHz to 12.5 MHz. Setting frequency with the change oscillator; Modes of Operation: CW and AM telephony; Power Requirements: 110/220 VAC or 12 VDC voltage ;Origin:ex Yugoslavia.
SCR-284-A Radio Set
Radio set SCR-284-A was produced by the United States in 1944. The Yugoslav Army have got this radio device in the package of military assistance that provided the United States after the World War II. It is interesting that the United States, have not just Yugoslav given this device as military assistance, the device could be found in the Soviet Red Army. This radio device the U.S. Army last used in the war in Korea, and later the army withdrew device from the use because of outdated.
Radio set SCR-284-A, in its time, was known as very high-quality and compact device. The base of the device was made from transceiver BC-654-A. Depending of the configuration of set their was the transport option for installation in the vehicle and pack unit for the transport by man or horses. Receiver BC-654-A was made in the technology of electronic tubes and it worked in the frequency range from 3.8 MHz to 5.8 MHz amplitude modulated (AM) telephony and telegraphy (CW). Frequency of receiver and transmitter was setting separately, continuous. They were placed in the same case. The device reached the maximum output power of 17 W at the AM modulation, and 24 W with the CW telegraphy. Receiver was superheterodyne with intermediate frequency of 455 KHz.
Transceiver BC-654-A was powering on with 6 VDC or 12 VDC voltage from lead battery, over vibrator converter type PE-104 and dinamo converter type PE-103. Portable version had in its set a manual generator type GN-45. Both versions of the radio devices SCR-284-A had in his set accessories for serving (microphone, Morse key, headset and loudspeaker), cables for connect and powering, antennas (rod and wired) and bags for packing and transporting.
The radio device is the beginning was setting in United States SUVs Jeep Villys or Dodge, received as military assistance for the United States. Later was setting in the Yugoslav vehicle "Zastava AR-55" made in the car factory "Zastava" in Kragujevac, licensed by the Italian "Fiat".
Technical Specification: Frequency Range: 3.8 MHz to 5.8 MHz; Modes of Operation: CW and AM; Output power of transmitter: 17 - 24 W; Power Requirements: 6 VDC or 12 VDC voltage from lead battery; Origin:United States.
AN/GRC-9 Radio Set
HF radio set AN/GRC-9 was produced in 1950. year in the United States. Yugoslav People's Army was received this device as part of NATO help in 1952. In Yugoslav Army it was the basic HF device in infantry battalion for link with the regiment - brigade.
Frequency range of the receiver and transmitter from 2 MHz to 12 MHz and in part from 2 MHz to 3 MHz it was reaching the upper part of the middle waves (MW). Types of modulation are CW (continuous-wave telegraphy) and AM (amplitude modulated telephony). He was having output power of transmitter from 20 W that has provided by strong pentode with direct heating 2E22. Transmitter and receiver were separated, but they were in the same case.
Before establishing of the connection, radio operator had to set frequency of receiver and transmitter to "zero" (on the same value). Complete radio set AN/GRC-9 was produced in the technology of electronic tubes in U.S. production.
It was powering on from lead batteries from 6 VDC, 12 VDC or 24 VDC voltage over dinamo converters type DY-88, or vibrator converter type PE-237, but then the output power was lower. Charging the battery was performed by the generator RE-162S, and it could powering radio device in the "buffer action" with battery. Also in the set was manual generator GN-58-A-GY for charger of batteries. Receiver was powering on with a special battery type BA-48. Most of these devices were by the first general repair tinted in gray-olive colour of Yugoslav People's Army and labels were written in Serbo-Croatian language. Part of the U.S. electronic tubes was replaced by equivalent Yugoslav production.
Used as a portable radio set, or incorporated in the vehicle "Zastava AR-55V" made in the car factory "Zastava" in Kragujevac, together with the VHF radio device RUP-1(2) and as that they consisted one HF / VHF system. With devices were managing through device driver boxes UK-6. Older radio operators were extremely priced this device and from it created a legend. Learn more about this device on the site www.grc9.nl.
Technical Specification: Frequency range: 2 MHz - 12 MHz; Modes of Operation: AM (amplitude modulation) and CW (continuous-wave); Power Requirements: 6 VDC, 12 VDC or 24 VDC voltage from lead batteries;Origin: United States.