{"id":6355,"date":"2020-09-25T01:11:00","date_gmt":"2020-09-24T15:11:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2020\/09\/25\/global-specialties-corporation-6000-frequency-counter-anyone-have-a-plessey-sp8630b-chip\/"},"modified":"2025-07-21T20:48:07","modified_gmt":"2025-07-21T10:48:07","slug":"global-specialties-corporation-6000-frequency-counter-anyone-have-a-plessey-sp8630b-chip","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2020\/09\/25\/global-specialties-corporation-6000-frequency-counter-anyone-have-a-plessey-sp8630b-chip\/","title":{"rendered":"Global Specialties Corporation 6000 Frequency Counter — Anyone have a Plessey SP8630B Chip?"},"content":{"rendered":"<\/p>\n
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Continuing my effort to improve my workbench and its test gear, this week I turned to an old frequency counter that I picked up at the Kempton Park Radio Rally in London many years ago. It was not working when I got it, but long-time SolderSmoke listeners will recall the tale of woe <\/a>that resulted from my having soldered a replacement IC (that Tony Fishpool G4WIF had sent me) UPSIDE down. Tough times my friends, tough times. <\/b><\/p>\n

Well, I’m working on it again. First I converted it from 220 to 110 power. I had a transformer in the junk box that fit nicely, both electrically and mechanically. In the course of doing this, I learned something about this counter that I did not know: As long as it is plugged in, even if you turn it off, the time-base oscillator keeps running. And get this Color Burst Liberation Army members: The oscillator runs at 3.579545 MHz. TRGHS. <\/b><\/p>\n

With sunspots scarce and with Pete pessimistic about the solar cycle, VHF and UHF now seem more interesting. I need to have more test gear for the higher frequencies. This counter works up to 650 MHz. Yea! <\/b><\/p>\n

When I first fixed this thing, I was quite pleased to get it going with “Input A — 5 Hz to 100 MHz.” But now I want to get “Input B — 40 MHz to 650 MHz” working also. <\/b>I used a 50 MHz signal from my newly repaired HP-8640B to trouble shoot Input B. I think one of the divider chips is bad. It is a Plessey SP 8630B. Does anyone have one of these chips in their junk box? <\/b><\/p>\n<\/p>\n

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Continuing my effort to improve my workbench and its test gear, this week I turned to an old frequency counter that I picked up at the Kempton Park Radio Rally in London many years ago. It was not working when I got it, but long-time SolderSmoke listeners will recall the tale of woe that resulted … Continue reading “Global Specialties Corporation 6000 Frequency Counter — Anyone have a Plessey SP8630B Chip?”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":6356,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[329,71,119,129],"tags":[],"class_list":["post-6355","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-fishpool-tony","category-test-gear","category-uk","category-vhf"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/6355","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=6355"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/6355\/revisions"}],"predecessor-version":[{"id":6359,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/6355\/revisions\/6359"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/6356"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=6355"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=6355"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=6355"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}