Kanga_products_Phoenix_Mk2_使用说明书手册

KANGA PRODUCTSElectronic Kits For The Radio Amateur'Phoenix'Crystal Set Mk2Back in the 1920's the first radios that the general public had access to were simpleunpowered receivers.With only one or two receivable stations selectivity was not really aproblem.Over the years many designs have been used some simple and easy to reproduceand others complicated but offering higher performance levels.For mary these radios have lost favour as we use modern sensitive receivers that offerroom filling volume with a wide choice of different stations that would be impossible tohear with the simplest crystal radio and its headphones.Many people despite the short comings of these early radios still enjoy building and usingcrystal radios,it's a magical feeling listening to a radio that never needs batteries andjust pulls its power directly from the signal in the sky.The Crystal radio kit here winds back time to give you the experience that early radiopioneers felt but uses modern quality parts that give good levels of performance moresuited to todays crowded medium wave band.The kit here is complete with a 'Vintage'looking enclosure and front panel in the style ofradios by companies such as heathkit,this style was typical for radios of the 1950's butthe technology used was still 1920's!.Typical Crystal Radio Circuit from the 20'sThis was a popular circuit thatANTENNAstill is used today in maryCrystal radio Kits,it doesCrystal Radiohave some problems.With theOA7antenna connected directly tothe top of the coil the300mHselectivity is low and the set240PFTuneMONO JACKmay only pick up one or twostations,often the samestat ions can be heard at allpoints of the tuning control atGNDthe same time.This circuitwas fine in the early days of radio when there was only one local station to hear aryway.With good quality parts the circuit here is still usable today despite its short comings.This design was improved upon by 'tapping'the coil so that the diode could be connectedat some point further down the coil than the top,the purpose of doing this was to reducePhoe rix Crystal RadioV2 from karga-products.co.ukPage 1 of 1121/2/21