Introduction, General | Realistic DX-75 specification

INTRODUCTION

The Realistic DX -75Communications Receiver is desig'ned to I rvideboth the usual "long wave" standard broadcast recei)tionand'shortwave'international broadcastrecep- tion. Therefore, it allows the listener to span the oceans ald travel around the world by means of radio waves.

of radio waves.

Short wave radr,r signals arcused forlong distance trans- nission becausc of the way they are reflectcd back to earth by the ionosplx'rcRadiation.frorn space (primarily Ironr thc sut)causes ioniz:ltioll olthe loycrs oI gascs higlt above thc carth. Shott wrr,rt r-acliosignals rvill not pcne- trate t.hcsetonizedgascs; rnst.ead,they bounce back to earth much like a stone skips across the surface of quiet watcr. Variations in thc reflccting charactcristics of tlre ionospheredue to sun spots, scasons, time of day, etc., producc periods when the skipping of short wave signals is espccially effective. Sincc nrany of these periods oc- cur h regular cycles the listener may develop a sched- ule of the best times to listen for sisnals from distant Darts of the world.

Listed below are sone of the many types of broadcasts

[hat can be heard on the short wave bands:

Amateur Radio (Ham)

Mobile Radio - Telepirone

Military

Citizens Band(CB)

lnt. Short Wave (Voice of America, etc. ) Standard Time Sigrnls (WWV)

GENERAL

Thc Realistic DX-75 is a four band AM receiver which covcrs the standarcl broadcast frequencies in one band: 550 to 1600 KC; and the short wave frequencies in t l r r e eb a n d s : 1 . 6 t o 4 . 4 M C ; 4 . 5 t o f l M C ; l l t o 3 0 M C .

Utilizing four tubes (one multipurpose tube affords five tube perf ormance) plus rec tif ie r, the superhetrodyne c i r - cuit is designedto operate from a 105 to l25volt, 60 cycle power source. A power transformer eliminates the haz - ard of a hot chassis. Housed in a vinyl clad steel taple model cabinet, the receiver features an eight inch "slide rule" type dial with continuous tuning of all four bands, plus bandspread for precise location of signals on tie busy short wave bands.