{"title":"A transmission line and radiating system measurement","authors":"W. Biggerstaff","doi":"10.1109/IRETVC1.1957.225088","DOIUrl":"https://doi.org/10.1109/IRETVC1.1957.225088","url":null,"abstract":"One of the major problems in mobile system maintenance is adequate evaluation of the transmission line and antenna performance. This paper describes a practical method of technique for making line loss and antenna match measurements to assure proper installation and continued satisfactory performance. Certain innovations have been incorporated in the process which are calculated to provide the maximum information with a minimum effort. The procedure consists essentially of making two transmission line input admittance measurements at widely differing frequencies. The results are plotted on a simplified version of the Smith Chart in a manner that yields transmission line loss and antenna match, These two properties adequately evaluate the transmission system for maintenance purposes. Both measurements are made at the input end of the transmission line without altering or disturbing the antenna or load end of the line. This is important where tall towers are involved or the antenna is otherwise not readily accessible. Accuracies are more than adequate for service purposes and the results are consistent under a wide variety of conditions. A simple technique for determining the distance in feet to a fault such as a break or short circuit is also described.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1957-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129121631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparison of wideband and narrowband mobile circuits at 150 megacycles","authors":"H. W. Nylund","doi":"10.1109/IRETVC1.1957.225087","DOIUrl":"https://doi.org/10.1109/IRETVC1.1957.225087","url":null,"abstract":"This paper gives results of laboratory tests made to evaluate the relative transmission performances of wideband and narrowband mobile radio telephone circuits in the 150 mc band. It was found that the effects of changing from wideband to narrowband operation are dependent upon RF impulse noise, frequency errors and RF signal levels. Under ideal conditions the change to narrowband may improve circuit performance; but where impulse noise interference is severe circuit performance will be seriously degraded unless rather large compensating changes can be made in such factors as RF signal power or average modulating levels.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1957-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122403395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Introduction to panel discussion on mobile radio vehicular interference","authors":"J. Chappell","doi":"10.1109/IRETVC1.1957.225091","DOIUrl":"https://doi.org/10.1109/IRETVC1.1957.225091","url":null,"abstract":"Vehicular electrical systems have the inherent capability of generating broad-band type impulsive interference, which, if effective control measures are not taken, will seriously degrade the performance of mobile communications receivers installed in the vehicle or installed in nearby vehicles. Thus we have two distinct problems: one, the interference to the communications receiver by the vehicular carrier; two, interference to the communications receiver from the electrical systems of nearby vehicles. The term broad-band interference describes the spectrum character of this interference which manifests its presence over a broad spectrum of frequencies extending from the very low radio frequencies to at least 1,000 mc. Figure 1 illustrates some of the properties of broad-band impulsive type interference. It will be noted that the idealized case of a pulse of infinite height and infinitesimal duration will result in a uniform spectrum from dc to infinity. More realizable pulses of rectangular and triangular shape respectively would have a spectrum such as shown in the lower portion of Figure 1. It will be noted that the spectrum amplitude, in the flat portion of the spectrum is substantially a function of only the volt-time area of the pulse, whereas at the higher frequencies the spectrum amplitude is a function of both the volt-time area and the pulse shape.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"7 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1957-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113980071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"VHF radio coordinated traffic light control system","authors":"E. Hassel","doi":"10.1109/IRETVC1.1956.207435","DOIUrl":"https://doi.org/10.1109/IRETVC1.1956.207435","url":null,"abstract":"Radio coordinated traffic light control permits the elimination of the conventional multiconductor cable which must tie together all traffic lights in a system. A VHF carrier modulated with audio-frequency control tones permits the radio coordinated system to perform the same as with the use of a cable plus the possibility of gaining additional benefits. All conventional traffic light control equipment may be used without modification. Several systems have been installed with complete success, gaining advantages in cost and flexibility. It may be expected that this form of control will grow rapidly within the next few years.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122533157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Transistorized communications receiver","authors":"S. Schwartz","doi":"10.1109/IRETVC1.1956.207441","DOIUrl":"https://doi.org/10.1109/IRETVC1.1956.207441","url":null,"abstract":"The purpose of this project was to use silicon transistors in place of vacuum tubes in all sections following the mixer stage of a military type communication receiver. The hybrid receiver built, while keeping the desirable characteristics of the vacuum tube receiver also provided for an increase of audio power and a reduction of battery power drain.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114755810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crystal oscillators in communication receivers","authors":"A. Manke","doi":"10.1109/IRETVC1.1956.207436","DOIUrl":"https://doi.org/10.1109/IRETVC1.1956.207436","url":null,"abstract":"The application of crystal oscillators to communications receivers is considered and the problems encountered are enumerated and separately analyzed. In regard to crystal oscillator operation, two typical circuits are cited for illustration and are analyzed in regard to the type of feedback used to produce oscillation. The analysis concludes that for maximum oscillator reliability in obtaining the inherent stability a crystal is capable of; regenerative feed-back which is present irrespective of the crystal impedance should be avoided and that these effects are largely determined by the type of crystal oscillator circuit used in a particular application. Over the temperature range normally encountered in communication receiver applications the reversals in the frequency vs. temperature characteristics for a typical close tolerance un-heated crystal is shown in Fig. #1. This data shows that for this type of crystal the total drift for temperature extremes is less rather than maximum due to the curvature of the frequency vs. temperature characteristic. Typical spurious responses of crystals normally used for oscillator purposes are also shown and the possibility of operation on spurious of the crystal is considered from a circuit viewpoint. Preferred methods for crystal oscillator injection and frequency trim are also discussed.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117142118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"UHF communication system interference reduction through the use of selective filters","authors":"M. W. Caquelin","doi":"10.1109/TCOM.1957.1097489","DOIUrl":"https://doi.org/10.1109/TCOM.1957.1097489","url":null,"abstract":"Modern trends in uhf communication systems indicate an ever increasing use of greater numbers of channels, higher transmitter powers, and decreased antenna spacing. This all adds up to an ever increasing number of systems interference problems. In most instances, a system can be rendered \"interference free\" by adding sufficient selectivity between the receiver or transmitter and its antenna. This added selectivity can be acquired by the use of a new low-loss tunable filter employing two high-Q, aperture coupled, resonant cavities in tandem. The physical construction of these equipments, as well as operating characteristics, will be discussed in this paper.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114719126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparison of split channel FM and single sideband for land mobile services","authors":"A. Macdonald","doi":"10.1109/IRETVC1.1956.207442","DOIUrl":"https://doi.org/10.1109/IRETVC1.1956.207442","url":null,"abstract":"","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132751586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A semi-automatic tuning high frequency communications equipment","authors":"M. Dettman","doi":"10.1109/IRETVC1.1956.207439","DOIUrl":"https://doi.org/10.1109/IRETVC1.1956.207439","url":null,"abstract":"This paper describes a high frequency two way communication equipment designed for vehicular mounting. A high degree of frequency accuracy and stability along with simplified semi-automatic transmitter tuning is featured. In addition to voice and code transmission and reception capability, facilities for frequency shift keying and teletype operation without the need of additional conversion equipment or power supplies are provided. A telephone and ringer circuit operating over the two wire remote control line is incorporated. Photographs and block diagrams of the various units are shown.","PeriodicalId":263631,"journal":{"name":"IRE Transactions on Vehicular Communications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1956-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121480224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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