{"id":1343,"date":"2018-09-26T20:34:51","date_gmt":"2018-09-27T03:34:51","guid":{"rendered":"http:\/\/philcoradio.com\/library\/?page_id=1343"},"modified":"2018-09-26T20:34:51","modified_gmt":"2018-09-27T03:34:51","slug":"aligning-adapter-for-mystery-control-philcos","status":"publish","type":"page","link":"https:\/\/philcoradio.com\/library\/index.php\/shop-talk\/techniques\/aligning-adapter-for-mystery-control-philcos\/","title":{"rendered":"Aligning Adapter for Mystery Control Philcos"},"content":{"rendered":"<p>This weekend, I messed around a little bit with the Mystery Control portion of my 41-616.<\/p>\n<p>As you may know, in the alignment instructions for these sets, the 2A4G is to be removed and replaced with an &#8220;aligning adapter&#8221; that has a red and black lead. However, no hint whatsoever is given as to what pins the red and black leads connect to in this &#8220;aligning adapter.&#8221;<\/p>\n<p>Well, folks, I believe I have solved this &#8220;Mystery.&#8221;<\/p>\n<p>I picked up a little analog multimeter today just for this purpose. I discovered that by using pins 5 (2A4G grid) and 8 (no connection inside the 2A4G, more on that later), it is very easy to align the Mystery Control circuitry using an analog multimeter or VTVM (the instructions call for a VTVM).<\/p>\n<p>I have now fabricated my own &#8220;aligning adapter,&#8221; and I am going to tell you how you can do the same in a few minutes.<\/p>\n<p>First, though, let&#8217;s look at the Mystery Control portion of the 41-616 circuitry.<\/p>\n<div class=\"resizedImageContainer\">\n<p><img decoding=\"async\" class=\"mycode_img\" src=\"\/library\/images\/tech\/aligning%20adapter%20for%20mystery%20control%20philcos\/41616_mc.jpg\" alt=\"[Image: 41616_mc.jpg]\" \/><\/p>\n<\/div>\n<p>The\u00a0<span class=\"mycode_color\" style=\"color: #ff0000;\">red<\/span>\u00a0lead should be connected to pin 5 (grid) of the 2A4G. As for the black lead, there is a wire under the chassis connected between the plate of the 6ZY5G and pin 8 of the 2A4G tube socket.<\/p>\n<p>The 2A4G does not use pin 8 internally. And nothing else connects to pin 8 of the 2A4G socket, so it is not being used as a tie point.<\/p>\n<p>I reasoned therefore that this must be where the black lead goes.<\/p>\n<p>I tried connecting the analog multimeter between pins 5 and 2 and obtained a reading, but I seemed to get a better reading using pins 5 and 8.<\/p>\n<p><em><strong><span class=\"mycode_b\"><span class=\"mycode_i\">How to make your own aligning adapter<\/span><\/span><\/strong><\/em><\/p>\n<p>You need an old octal tube base, one from a &#8220;G&#8221; type tube so it will fit inside the socket and tube shield base. Make sure the tube base you use has pins 5 and 8!<\/p>\n<p>Solder a red wire inside the tube base to pin 5.<\/p>\n<p>Solder a black wire inside the tube base to pin 8.<\/p>\n<p>Your aligning adapter will look like this:<\/p>\n<div class=\"resizedImageContainer\">\n<div><img decoding=\"async\" src=\"http:\/\/philcoradio.com\/phorum\/images\/icons\/information.png\" alt=\"\" \/>The image has been resized to 945x709px. Click here to show the original size of the image.<\/div>\n<p><img decoding=\"async\" class=\"mycode_img\" src=\"\/library\/images\/tech\/aligning%20adapter%20for%20mystery%20control%20philcos\/2012-05-13_00002.jpg\" alt=\"[Image: 2012-05-13_00002.jpg]\" \/><\/p>\n<\/div>\n<p><em><strong><span class=\"mycode_b\"><span class=\"mycode_i\">How to Use:<\/span><\/span><\/strong><\/em><\/p>\n<p>Follow the factory alignment instructions, and use your new homemade aligning adapter when the instructions call for using this.<\/p>\n<p>Set the multimeter to the highest AC voltage range, setting it to a lower range if necessary. Do not start at a low AC voltage range, or else you may damage your meter.<\/p>\n<p>Red lead of the meter to red lead of aligning adapter, black lead of meter to black lead of aligning adapter.<\/p>\n<p>This will yield a much more accurate alignment than merely watching for the 2A4G to glow, as called for in the 1939 alignment instructions.<\/p>\n<p>Here&#8217;s a look at the aligning adapter in use, connected to my new multimeter:<\/p>\n<div class=\"resizedImageContainer\">\n<div><img decoding=\"async\" src=\"http:\/\/philcoradio.com\/phorum\/images\/icons\/information.png\" alt=\"\" \/>The image has been resized to 945x709px. Click here to show the original size of the image.<\/div>\n<p><img decoding=\"async\" class=\"mycode_img\" src=\"\/library\/images\/tech\/aligning%20adapter%20for%20mystery%20control%20philcos\/2012-05-13_00001.jpg\" alt=\"[Image: 2012-05-13_00001.jpg]\" \/><\/p>\n<\/div>\n<p>When a signal is applied from your signal generator to the input screw terminals where the Mystery Control loop antenna is normally connected, you will achieve a very high reading on your meter. Notice in the photo above, the meter is set to the 150 volt AC range, and it is reading around 90 volts AC! So\u00a0<span class=\"mycode_b\"><span class=\"mycode_i\">be careful, and do not touch the leads when performing the Mystery Control alignment!<\/span><\/span>\u00a0Safety first!<\/p>\n<p><span class=\"mycode_b\"><span class=\"mycode_i\"><em><strong>WARNING<\/strong><\/em><\/span><\/span><\/p>\n<p><em><strong>Be sure that you never, ever touch pin 3 of the aligning adapter! There is raw AC on pin 3, and it is\u00a0<span class=\"mycode_u\">not<\/span>\u00a0isolated from the household AC line!<\/strong><\/em>\u00a0A good way to prevent this from happening is to fill the tube base with hot glue, not completely, but just enough to cover all of the pin connections inside.<\/p>\n<p>Hopefully this will prove helpful to you whenever you need to align the Mystery Control circuits of 1939-1942 Philco sets.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>This weekend, I messed around a little bit with the Mystery Control portion of my 41-616. As you may know, in the alignment instructions for these sets, the 2A4G is to be removed and replaced with an &#8220;aligning adapter&#8221; that has a red and black lead. However, no hint whatsoever is given as to what [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1317,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1343","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1343","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=1343"}],"version-history":[{"count":0,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1343\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/pages\/1317"}],"wp:attachment":[{"href":"https:\/\/philcoradio.com\/library\/index.php\/wp-json\/wp\/v2\/media?parent=1343"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}