[Today’s run:\u00a0 3.4 ]<\/p>\n
Like a lot of my projects, about 80% is working up the motivation and the idea about how to do the thing.\u00a0 That’s the problem with being a perpetual amateur:\u00a0 I don’t do these things often enough to get a professional type frame of mind and angle of attack.<\/p>\n
I did read the troubleshooting information in the manual I downloaded.\u00a0 That helped.They outline a general back-to-front attack:\u00a0 start with the audio output and work back toward the front end where the antenna connection is.\u00a0 I injected an audio signal and that came out.\u00a0 Then I was a bit confused as to whether the audio driver was working correctly or not.\u00a0 I sat on it for awhile.<\/p>\n
Yesterday I decided to check the various oscillators to see if they were working.\u00a0 The manual talks about using a receiver to listen for them, so I did that.\u00a0 The front end crystal oscillators and the VFO appeared to be working.\u00a0\u00a0 I had a length of coax and I attached a little coiled wire with some clip leads and I moved the coiled wire around.\u00a0 I used my SDRplay and I could see everything on the spectrum\/waterfall display.<\/p>\n
I got to a stage where there is a 405 kHz oscillator which mixes down 455 kHz to 50 kHz.\u00a0 And I could not find the 405 kHz signal. There is an oscillator in the grid\/cathode circuit which had 2 resistors, 2 capacitors and a canned coil.\u00a0\u00a0 I put my little loop over the top of the oscillator tube and.. nothing.\u00a0\u00a0 I tried to measure the component values and everything seemed to measure OK.\u00a0 But I still couldn’t get any sign of the 405 kHz signal.\u00a0 Swapped tubes, tried everything.<\/p>\n
So I ended up taking that canned coil and the attached components out.\u00a0 I detached the components and measured them.\u00a0 I measured the coil.\u00a0 Everything looked good.\u00a0 I put it all back together and put it back in.\u00a0 And the 405 kHz oscillator is back larger than life.\u00a0 I had to adjust the coil a bit, easy as can be.\u00a0 Now the radio is playing like it never had a problem.\u00a0 Maybe it was a cold solder joint or something, I don’t know.<\/p>\n
I’m going to let it play this afternoon then maybe I will run through the “tune up” procedure this evening and peak all of the IF cans and such.<\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
[Today’s run:\u00a0 3.4 ] Like a lot of my projects, about 80% is working up the motivation and the idea about how to do the thing.\u00a0 That’s the problem with being a perpetual amateur:\u00a0 I don’t do these things often enough to get a professional type frame of mind and angle of attack. I did […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-6685","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/6685","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6685"}],"version-history":[{"count":3,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/6685\/revisions"}],"predecessor-version":[{"id":6688,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/6685\/revisions\/6688"}],"wp:attachment":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6685"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6685"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6685"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}