- At the finish of the six-year plan (1)
"We are only a month away from the final completion of the great and glorious work - the 6-year Plan. It is as if a few steps to the finish line of the entire nation's sacrificial race of work. In a few weeks, a considerable section of the road will be behind us, on which we had to overcome the many, often difficult, difficulties. Approaching the finish line, and then looking back at the time-consuming and exhausting stage of our peaceful construction - we will undoubtedly do what the custom does not need to remind a good host:... " - Let's learn radio engineering: Ways to protect electrical equipment against harmful radio interference (2)
"In this article, we will discuss the technical means by which radio interference is fought at the very source of their occurrence, that is, with all kinds of power devices that cause either periodic or periodic interruption of current, or abrupt changes in current in electric network cables (in the previous article already explained why such current surges are the source of radio interference)..." - Practical problems of amateur radiotelephony, part III (4)
"Grid modulation with carrier wave regulation
As already mentioned - the low average energy efficiency of a modulated amplifier in the grid can be increased by using so-called regulation (control) of the carrier wave level (carrier control). In conventional modulation systems - the power of the carrier wave itself is constant and does not depend on the presence of modulating voltage. The average depth of modulation is small, the transmitter is fully modulated only at moments, and already in the intervals between words or syllables the carrier wave is sent to the "ether" completely useless..." - Soviet equivalent of R-type electron tubes (6)
"RGN564 ÷ BO!, RGN2004 ÷ BO116/BO188, RGN1064 ÷ BO125/BO197/BO202..." - ZSW-2 control unit (8)
"Slowly but surely - the range of equipment manufactured by our industry for the needs of wired radio is expanding. Among other things, the ZSW-2 power amplifier control unit has already been used, its schematic diagram is shown in the figure. This set includes: a receiver, a microphone amplifier, a power supply and a control speaker.
A radio program or local broadcast (microphone, adapter) can be transmitted via the control unit. The control loudspeaker allows you to tune the receiver and control the broadcast while the radio is operating..."
- From the competition "Polni Den" 1955 - SP9KAG on Velka Raca (10)
"Gliwice Communications Club prepared three teams for "Polni Den", which were to take part in the competition under the signs SP9KAG, 9UAO, 9OAR for the first time. Because the club's VHF section was established only a few months ago and we didn't have any experience in this field, it was decided to work during the competition only in the 144 MHz band as the easiest to master..." - Czechoslovakia - Switzerland at 144 MHz - SP5FM (11)
"The European Two Meter Day, which took place on 3/4 September this year. brought the Czechoslovak OK1VR station an extraordinary success. She established at 0312 CET connects to the Swiss HB1IV station in the 144 MHz band, thus setting a new Czechoslovakia record..." - VHF competition results (12)
"The SVAZARM Jury Commission announced the results of the shortwave competition "Den Rekord VKV 1955". 42 teams took part in this competition, including one Polish..." - Two-way radios on decimeter waves (13)
"The GDR produces series radios working on decimeter waves and intended for communication in enterprises, institutions, construction sites, mountain areas, at sports competitions, etc...." - TV receiver for long-range reception (14)
"By publishing the description of my TELEAMATOR, it seems to me that I am fulfilling the wish of a large number of television lovers who have been flooding letters from both the Editorial Board and the author himself for a long time...." - Broadcast amplifier type WR-550 (19)
"The domestic radio engineering industry produces already a large range of amplifier equipment for the needs of wired broadcasting, among others WR-550 amplifiers, designed to work in larger radio stations, which should be equipped with medium or high power station equipment. The WR-550 amplifier can be connected to power lines (fiders) with a voltage of 120 V or 240 V, or local subscriber lines with a voltage of 30 V and a load of 150 W..." - From amateur radio practice (22)
"We publish three notes sent by our readers. One of them gives information on how to stabilize the position of the wire blade in a selected sensitive spot of the detector crystal, the second - a description of the amateur performance of the lamp bases, the third - a description of an easy to make in-house vibration generator..." - Nomogram: Broadband amplifiers (part III) (25)
"In the low frequency range (as well as at higher frequencies) there are, apart from the weakening of the gain, harmful phase shifts, causing pulse distortion..." - We give an "Inadequate rating" (27)
"A two-act pencil by Kazimierz Woliński..." - Lightning rods and antennas (28)
"It is known that the issue of protection against the effects of electrical lightning is difficult and complex. Difficulties to strictly determine technical measures that effectively protect against lightning arise due to the great voltages involved, the large scale intensity of individual discharges, and the large number of tangible factors affecting the degree of danger of lightning to humans, animals and equipment in each individual case..." - Exchange (30)
- Our readers write (32)
- New releases (cover III)
- Do you know that (cover IV)
PDF : Radioamator 1955/11 v1
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