{"id":1227,"date":"2018-09-22T19:54:24","date_gmt":"2018-09-23T02:54:24","guid":{"rendered":"http:\/\/philcoradio.com\/library\/?page_id=1227"},"modified":"2018-09-25T21:12:44","modified_gmt":"2018-09-26T04:12:44","slug":"extra-coil-in-model-19tx-front-end","status":"publish","type":"page","link":"https:\/\/philcoradio.com\/library\/index.php\/shop-talk\/model-notes\/extra-coil-in-model-19tx-front-end\/","title":{"rendered":"Extra Coil in Model 19TX Front End"},"content":{"rendered":"<p>When you turn the chassis of a Model 19TX upside down, you will receive a surprise &#8211; an extra coil mounted underneath!<\/p>\n<p>The coil is physically located close to antenna coil (2), and is mounted in a cylindrical container which looks similar to the set&#8217;s second IF transformer. It has three terminals on top. The pictorial below shows the placement of the coil, labeled &#8220;Balun&#8221; in the drawing.<\/p>\n<p><img decoding=\"async\" class=\"mycode_img\" src=\"\/library\/images\/tech\/extra%20coil%20model%2019tx\/19tx_bottom.jpg\" alt=\"[Image: 19tx_bottom.jpg]\" \/><\/p>\n<p>The parts layout above does not match the 19TX exactly. The drawing is from a Model 89 Code 123, modified to show where the extra coil is mounted. An actual factory under-chassis drawing of a Model 19 Code 126 has yet to be found, which the 19TX (Code 127) is based on.<\/p>\n<p><img decoding=\"async\" class=\"mycode_img\" src=\"\/library\/images\/tech\/extra%20coil%20model%2019tx\/19tx_balun.jpg\" alt=\"[Image: 19tx_balun.jpg]\" \/><\/p>\n<p>The partial schematic above shows how the coil mounts in the circuit.<\/p>\n<p>It appears these sets were set up at the factory to be used with the Philco Three Purpose Aerial which was available at the time (mid-late 1933), which used a twisted pair lead-in which connected to a balun transformer which was to be mounted close to the set&#8217;s antenna and ground terminals. In the case of the 19TX, it does not have antenna and ground terminals mounted on the chassis &#8211; rather, the lead-in wires go through a 25-foot cable to the set&#8217;s separate speaker cabinet (see\u00a0<a class=\"mycode_url\" href=\"http:\/\/www.philcoradio.com\/phorum\/showthread.php?tid=14982\" target=\"_blank\" rel=\"noopener\">Speaker Hookup, Models 14LZX-19LZX-19TX-91RX<\/a>\u00a0for more information on this). Thus, the balun is mounted inside the chassis of the 19TX.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>When you turn the chassis of a Model 19TX upside down, you will receive a surprise &#8211; an extra coil mounted underneath! The coil is physically located close to antenna coil (2), and is mounted in a cylindrical container which looks similar to the set&#8217;s second IF transformer. It has three terminals on top. The [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1319,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1227","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1227","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/comments?post=1227"}],"version-history":[{"count":0,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1227\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1319"}],"wp:attachment":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/media?parent=1227"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}