{"id":3135,"date":"2012-11-18T17:33:11","date_gmt":"2012-11-18T23:33:11","guid":{"rendered":"http:\/\/w0ep.us\/OM\/?p=3135"},"modified":"2012-11-18T17:40:05","modified_gmt":"2012-11-18T23:40:05","slug":"radio-projects-today","status":"publish","type":"post","link":"http:\/\/w0ep.us\/OM\/?p=3135","title":{"rendered":"Radio projects today"},"content":{"rendered":"

[No run today, yesterday we did 7.75 miles]<\/p>\n

This picture shows two (three) of my recent ham radio related projects.<\/p>\n

The radio on it’s side is an old National NCX-5.\u00a0 It’s a 5-band transceiver, mostly vacuum tubes.\u00a0 It puts out 150 watts (my most powerful transmitter!).\u00a0 I received this thing from another ham, Mark, KK5EK when he and I lived in Colorado.\u00a0 He had it floating around and it didn’t work.\u00a0 He gave it to me, very generous of him!\u00a0 I was able to get it working again and I used it for awhile.\u00a0\u00a0\u00a0 I have some notes on the schematic about things I fixed in 2002, so I know I’ve had it at least 10 years now.<\/p>\n

For the last few years it has been sitting on a shelf in the garage while I’ve used my TS-820 or the TenTec Century 21.\u00a0 [You know, all of those radios were given to me in unworking state.\u00a0 I sense a pattern here.]<\/p>\n

I read a website about an improvement to the CW operation.\u00a0 The thing was almost unbearable on CW.\u00a0 Every dit or dah would cause a nasty sound in the speaker.\u00a0 Anyway, W7CPA, on his website<\/a>, details a modification that will mute the audio more quickly in the transmit\/receive switchover.\u00a0 I finally got around to doing that and it works much better now.\u00a0 But I notice that it doesn’t have a sidetone.\u00a0 I don’t remember if it is supposed to have a sidetone… maybe not.\u00a0 Makes it a bit harder to use on CW.\u00a0 But that little lacking can be surmounted by using a keyer with a sidetone or by turning on the Century 21 and tuning in to my own signal (with no antenna attached).<\/p>\n

Success #1.<\/p>\n

You may also note in the picture that the O-scope is on and showing a 10 Mhz signal, somewhat square-ish, and the counter says 9,999,999.936 Mhz (trust me, that’s what it says).\u00a0 The counter is off by 0.064 hertz(!).\u00a0 Not too bad.\u00a0 Those results are from my much worked-over GPSDO (frequency standard).\u00a0 I think I finally have it working correctly.\u00a0 I touched up the soldering of a couple of spots on the circuit boards inside the HP crystal unit.\u00a0 That seems to have done the trick.\u00a0 The control voltage is now doing it’s thing and the controller card can “steer” the oscillator to keep it in line with what is coming in via the GPS card. \u00a0 I’ll run it for a few days (weeks.. months..) and see.\u00a0 The laptop to the left is recording the log from the GPSDO so I can tell when it adjusts up or down and how far off it gets.<\/p>\n

Success #2 (tentative).<\/p>\n

Project #3 is the radio in the upper right corner of the picture which also has it’s cover off and is lying on one side.\u00a0 That is a Kenwood TR-751A 2 meter all-mode radio which I bought from an estate.\u00a0 It works fine for awhile then the audio quits.\u00a0 The rest of the radio appears to keep working fine.\u00a0 So I’m letting it run for awhile to see if I can make it happen.\u00a0 Then I’ll poke around with a pointy stick to find if there are any loose connections.<\/p>\n

\"\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

[No run today, yesterday we did 7.75 miles] This picture shows two (three) of my recent ham radio related projects. The radio on it’s side is an old National NCX-5.\u00a0 It’s a 5-band transceiver, mostly vacuum tubes.\u00a0 It puts out 150 watts (my most powerful transmitter!).\u00a0 I received this thing from another ham, Mark, KK5EK […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-3135","post","type-post","status-publish","format-standard","hentry","category-ham-radio"],"_links":{"self":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/3135","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=3135"}],"version-history":[{"count":7,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/3135\/revisions"}],"predecessor-version":[{"id":3143,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=\/wp\/v2\/posts\/3135\/revisions\/3143"}],"wp:attachment":[{"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3135"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3135"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/w0ep.us\/OM\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3135"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}