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VHF

The term Very High Frequency refers to frequencies in the range from 30 MHz (i.e. above the shortwave band) to 300 MHz. In German, this frequency range is also known as Ultrakurzwellen.

FM broadcasting band

The VHF broadcasting band, which is commonly referred to as FM broadcast band (or UKW in German sets), extends from 87.5 - 108 MHz. In Germany, initially only the range 87.5 - 100 MHz was used for FM broadcasting, from 1964 the range was extended to 104 MHz and from 1968 to 108 MHz, early FM radios sometimes do not cover the entire FM broadcasting range used today.

In Eastern European countries (except the GDR) the range 65.9 - 73.1 MHz was used for FM broadcasting, the so-called OIRT band is still partly in use today in parallel to the international FM broadcasting band.

In Japan, the 76 - 90 MHz range is used for FM broadcasting, and an extension to 95 MHz is planned. Television stations operated on the higher frequencies, and their audio signal could be heard with the VHF radios covering higher frequencies.

Military communications

During World War II, VHF frequencies between 30 and 88.5 MHz were increasingly used for military communications. The frequency modulation used in this band was less susceptible to interference, allowed the use of a squelch, but had increased frequency bandwidth requirements.

Radio for public authorities (Public Service Band)

The VHF range is used by a number of organisations, which in Germany are called Behörden und Organisationen mit Sicherheitsaufgaben (BOS, agencies and organizations with security duties). Intercepting the communications of police, ambulances, fire brigades, forestry services, etc. in Europe was illegal without proper authorisation and was severely punished for years.

Anyway, listening to signals on this „forbidden“ frequencies has always been a challenge for mostly younger enthousiasts. Receivers covering these „illegal frequencies“ were offered for sale as „export sets“. At least in Switzerland, the sale was permitted in order to be able to purchase a receiver before leaving the country where its use was legal. Thats why these sets were sold „for export only“.

The jurisdiction was somewhat different in the European countries.

  • in Germany the possession of a receiver covering frequencies outside the authorised broadcast bands was allowed with an appropriate licence, amateur radio operators were allowed to possess receivers for the 2 m - amateur radio band, for example. Without a licence, the normal listener was not even allowed to listen to the radio amateurs on the local relay station. Things even got more complicated, when the German authority FTZ decided to limit the shortwave range to 26.1 MHz. So under rule of the FTZ regulations, even the reception of CB radio around 27 MHz and radio amateurs in the 10 m band was no longer allowed without a licence. Due to this regulation, world band receivers had to be modified in order to be sold in Germany. Since this implementation of frequency restrictions was not worthwhile for small sales, some high-quality receivers were never offered in Germany, or the price for the modified sets was higher than for the standard sets reaching up to 30 MHz.
  • in Switzerland the regulations always were less restrictive. The possession of „export sets“ was allowed, only the interception of the corresponding frequencies was forbidden, if one did not possess a corresponding licence. Tuning in by accident was not punishable, i.e. if the band switch of a multi-band set was accidentally set to VHF instead of SW, this usually did not justify a fine or confiscation of the set. However, it was a punishable offence to make use of or pass on information obtained by listening on non-public frequencies.
  • in Italy the regulations were apparently even more restrictive, so also the maritime communications band between mediumwaves and the 49 m shortwave broadcast band had to be excluded, at least for some years. This led to special versions or modifications by means of solder bridges for Italy. Confiscations of „export sets“ were reported from Italy.

Public Service Communications took place on the one hand in the 4 m band between 68 and 87.5 MHz, on the other hand in the 2 m band between 165 - 174 MHz. In the 2 m band 146 - 174 MHz, some commercial communications were also allowed with a corresponding licence.

The PSB 2 m band should not be confused with the 2 m amateur radio band, which ranges from 144 - 146 MHz (in certain regions of the world 144 - 148 MHz) and which licensed radio amateurs are permitted to use for their radio traffic.

VHF Television

In the lower VHF range, the television transmitters of VHF band I of the analogue television system with the channels 2, 3 and 4 were active in the German-speaking countries; the sound carrier lies 5.5 MHz above the video carrier.

In the upper VHF range, the television transmitters of the VHF band III analogue television system were active. In the range between 174 and 230 MHz, the channels 5 - 12 according to the CCIR standard were transmitting, again the sound carrier is 5.5 MHz higher than the video carrier.
With the abolition of analogue terrestrial television, cable television networks are still using this frequency range; terrestrially, the frequency range is used for DAB (digital audio broadcasting).

Aeronautical communication

After the Second World War, aeronautical communications were transferred from shortwaves to the VHF range; aeronautical communication is the only radio service that uses amplitude modulation in this band.

For radiotelephony, the frequency range 118 - 137 MHz is used, originally in the 50 kHz, then in the 25 kHz and today in the 8.33 kHz channel spacing, so that the number of available frequencies could be multiplied.

The 108 - 118 MHz range is used by radio beacons, the VOR (VHF Omnidirectional Radio Range) beacons; the glide path beacons for instrument controlled landing approaches operate around the UHF range of 328 - 335 MHz.

Use of the VHF spectrum

(c) Zander Schubert, Wikimedia.com

en/vhf.txt · Zuletzt geändert: 2021/04/26 22:13 von mb