{"id":8421,"date":"2014-02-10T11:50:00","date_gmt":"2014-02-10T00:50:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2014\/02\/10\/bitx-2040-build-update-9-on-the-air-observations\/"},"modified":"2025-07-22T00:36:52","modified_gmt":"2025-07-21T14:36:52","slug":"bitx-2040-build-update-9-on-the-air-observations","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2014\/02\/10\/bitx-2040-build-update-9-on-the-air-observations\/","title":{"rendered":"BITX 2040 Build Update #9: On-the-air Observations"},"content":{"rendered":"
<\/a><\/div>\n

The BITX 2040 has moved from the bench to the operating position and is producing a steady stream of contacts on 20 and 40 meters. In the picture above it is the rig with the copper-clad front panel (the BITX 17 is below it). It has already crossed the pond on both bands.<\/strong>
<\/strong>
Some observations: <\/strong>
<\/strong>
I get significantly more power out on 40 than on 20: about 7.2 watts PEP on 40 and about 4.4 watts PEP on 20. I saw a QST article that showed similar frequency\/power out variations from IRF510 amps. But I notice I get more power out from my 17 meter rig. On that rig I am using trifilar (9:1 Z) transformer instead of the standard BITX bifilars. <\/strong>
<\/strong>
My 40 meter receiver is LOUD. Too much AF out. I am not used to having this problem! On this rig I am using the same discrete component 2n3904 2n3906 transformer-less circuit that I used in the BITX 17. But AF out on 40 was so loud that I had to go back and add 20 k ohms to the top of the volume control pot. I didn’t have this problem with the 17 meter rig, and I didn’t have it on 20 with this rig. Any ideas why this rig would be so loud on 40? <\/strong>
<\/strong>
I still want to go in and fine tune the crystal filters in both rigs. I am studying the various software packages out there (especially Wes’s LADPAC). I hope to get rid of the ripple.<\/strong> <\/p>\n

In most of my contacts with these rigs, I end up describing the circuit and its Indian origins. Most people are really fascinated. Yesterday W1IDL in Michigan suggested that I contact my Indian friends and get some assistance in making some Hindi or Urdu labels for the rig and the controls. I think that is a very cool idea. <\/strong><\/p>\n

Our book: “SolderSmoke — Global Adventures in Wireless Electronics” http:\/\/soldersmoke.com\/book.htm<\/a> Our coffee mugs, T-Shirts, bumper stickers: http:\/\/www.cafepress.com\/SolderSmoke<\/a> Our Book Store: http:\/\/astore.amazon.com\/contracross-20<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

The BITX 2040 has moved from the bench to the operating position and is producing a steady stream of contacts on 20 and 40 meters. In the picture above it is the rig with the copper-clad front panel (the BITX 17 is below it). It has already crossed the pond on both bands. Some observations: … Continue reading “BITX 2040 Build Update #9: On-the-air Observations”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":8422,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28,60,23],"tags":[],"class_list":["post-8421","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bitx20","category-hayward-wes","category-ssb"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8421","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=8421"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8421\/revisions"}],"predecessor-version":[{"id":8423,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8421\/revisions\/8423"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/8422"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=8421"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=8421"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=8421"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}