SparkFun Electronics Commentsurn:uuid:214d0e4e-f1b1-d287-ce26-ac5b4c9f82492024-03-29T00:48:48-06:00SparkFun Electronicsnor'easter on Introducing "Old Machine Time Machine"nor'easterurn:uuid:11e55ef0-cdaa-4354-309d-a7c71d6d362d2018-10-26T19:50:53-06:00<p>Switchcraft calls them "Vintage Microphone Connectors". Take a look at the dates on the chassis mount male connector drawing. http://www.switchcraft.com/Drawings/2501MP_CD.pdf</p>
Customer #455076 on Introducing "Old Machine Time Machine"Customer #455076urn:uuid:aa87d7dd-7c4b-5b09-a1ad-42d48306adf82018-10-26T10:28:05-06:00<p>The frequency pointer is NOT connected to the frequency knob, but instead to a planetary gear. This allows more resolution in setting the frequency.<p>The chassis is copper plated because steel has lower conductivity. The plating thickness is enough for a few skin depths for frequencies where they wanted better shielding.</p><p>I built many Heathkits including and AM-FM radio that received the first stereo transmissions from San Francisco, one channel on AM and one channel on FM.</p><p>Also built the big screen color TV with the built-in color alignment generator.</p><p>https://prc68.com/I/HeathkitGC1000.shtml#LoH</p></p>
Madbodger on Introducing "Old Machine Time Machine"Madbodgerurn:uuid:8a9b1f3f-3568-b67f-fbee-25264542bad42018-10-26T09:46:33-06:00<p>There's a fair amount of interest in old Heathkit gear. They made a bunch of cool TV test stuff, and while analog TV isn't broadcast much any more, people still find use for it. What do you have? Pattern generator? Vectorscope? VTVM? GDO? Demodulator probe?</p>
imabug on Introducing "Old Machine Time Machine"imabugurn:uuid:42e7a46e-41da-bf2a-120c-1e542c90e37f2018-10-26T07:41:13-06:00<p>PL-259 connectors do fit on them. I also don't know what they're called either, but it's pretty easy to replace with a BNC connector. The center of the connector is just a hole that the wire gets soldered into. A bit of heat from a soldering iron and the wire comes right out. Replace with a BNC, solder the wire to the middle pin and Bob's your Uncle.</p>
Customer #887589 on Introducing "Old Machine Time Machine"Customer #887589urn:uuid:bb8e2712-ce8b-8f59-d4ce-ebd462166c932018-10-26T06:47:43-06:00<p>By my reckoning, I have assembled, or trouble-shot for others, over 150 heathkits, from the electronic ignition kit to the electronic organ kit and most everything in between. I currently own a VTVM, Tube Tester, two Frequency Counters (one w/LED display and the other with NIXIE tubes for the display) and an amateur band receiver .</p>
Customer #1458650 on Introducing "Old Machine Time Machine"Customer #1458650urn:uuid:5ae47faf-d4b0-a610-b1b9-dcb6b251792f2018-10-24T19:48:01-06:00<p>I saw this while ordering some switches and wondered if anyone would be interested in some various Heathkit test TV equipment. I got them in a trade in the late '70s and while they have gotten beat up some I have hung on to them on the chance they might be wanted. If there is interest I would get them together and send pictures.</p>
Customer #134773 on Introducing "Old Machine Time Machine"Customer #134773urn:uuid:1a895b4b-45ab-b788-4985-997e75b5b5972018-10-24T07:40:44-06:00<p>Your comment made me think of the days about 40 years ago when I was working at a TV station as an engineer. When I was on duty, I had a calibrated monitor in front of me (it cost about $10,000 at the time, and had to go in for calibration once a year, so we had to have two of them). I recall walking through the TV section at Sears and thinking how far out of adjustment their demonstrators were. I also learned how few "TV service techs" had a clue as to how to properly adjust a TV, even if they had the right equipment. (Some of the Heathkits had it built in!) For at least 10 years after I left that job, I could only tollerate watching black and white TVs, which were much more forgiving!</p>
Customer #20299 on Introducing "Old Machine Time Machine"Customer #20299urn:uuid:f1bfe045-c215-7fee-992f-444a9aff249a2018-10-23T21:22:32-06:00<p>This comment made me smile. My dad built the Heathkit color TV when I was a kid. We had the best color TV of everyone I knew. Dad adjusted the guns on the CRT tube daily, so we had the only TV without color fringing. If you are old enough you will remember just how bad the color was on most TVs.</p>
Customer #134773 on Introducing "Old Machine Time Machine"Customer #134773urn:uuid:8839e6df-fd20-3485-67e9-58428ebc76a62018-10-23T18:41:06-06:00<p>Take a look at what DigiKey has for <a href="https://www.digikey.com/products/en/connectors-interconnects/coaxial-connectors-rf/437?k=PL-259" rel="nofollow">PL-259</a> -- BTW, a PL-259 is a PLUG (usually on the end of a coax cable). The mating socket is an <a href="https://www.digikey.com/products/en?keywords=SO-239" rel="nofollow">SO-239</a>. Why the number difference? Who knows? I sure don't.<p>Back to the connectors on your signal generator, I'm drawing a blank on trying to find a reference. As you likely know, the Heathkit manual only refers to them as "Shielded connectors", not a big help. I have some muck older things at home (like a Radio Amateur's Handbook from the 60s), but I'm not at home right now and so can't reference those things!</p></p>
Madbodger on Introducing "Old Machine Time Machine"Madbodgerurn:uuid:7023f8d7-4012-6fed-fe20-163728f716f82018-10-23T09:26:41-06:00<p>I was guessing the other tube was a 6C4, and sure enough, it is. It's basically half a 12AU7. You can find the manual here: http://tubularelectronics.com/Heath_Manual_Collection/Heath_Manuals_S/SG-8/SG-8.pdf Sure enough, that connector isn't a PL-259, just a generic microphone connector which was pressed into service for a lot of test gear (VTVMs, oscilloscopes, etc.) back in the day. Everybody made 'em, but I don't know of a standard name. It's probably a 5/8-27 thread, like Amphenol 85-75MC1F, Switchcraft 2501F, or J-30.</p>
Pete-O on Introducing "Old Machine Time Machine"Pete-Ourn:uuid:75e57cce-da7c-296a-73fc-433a7b593ca22018-10-23T08:49:02-06:00<p>'773! As always, thanks for the stories! Not a PL-259?? Ah, crud. I think the reason I said it is is because when I first saw one, I went, "ah, PL-259", and then proceeded to screw one onto it. At least, I think it fit. Or I cross-threaded that sucker into oblivion.</p>
Sembazuru on Introducing "Old Machine Time Machine"Sembazuruurn:uuid:eb8588bd-d5de-1aba-592f-52290b643cbf2018-10-23T08:42:27-06:00<p>For the longest time when I was growing up our main TV was a HeathKit that my father assembled, and never got around to putting an enclosure around... I'm sure now-a-days that would be criminal endangerment of a minor (two counts, one for me, one for my brother)... Neither my brother nor I hurt ourselves by putting our hands inside. Not for fear of HV electricity... No, that was fear of the Wrath of Dad. ;-)</p>
Customer #134773 on Introducing "Old Machine Time Machine"Customer #134773urn:uuid:4f18dcdb-5523-5369-d7d1-6a9a934c14022018-10-23T08:02:19-06:00<p>Pete, thanks for the fun video!<p>Youngster, I hate to correct you, but those are NOT PL-259's on the front. Off hand, I don't recall the number for them, but they are audio, not radio, frequency connectors. They are (were) often used for microphone connectors, until someone got the bright idea to put a "push-to-talk" button on the mike itself and needed a second pin.</p><p>Another hint as to the age of the thing is that it's marked "KC" and "MC" (for kilocycles per second and megacycles per second, respectively) rather than the more modern "KHz" and "MHz" (for kilohertz and megahertz).</p><p>Once in a great while there were professionals who needed some feature of a Heath Kit and would buy one and assemble it "on the company dime". Fourty years ago I worked as a broadcast engineer at a TV station for a few months, and (I suspect) the chief engineer had gotten a kit and built it for a clock that would auto-correct to the WWV radio signal. (Today you can just go down to the consumer electronics shop, or Amazon, etc., and buy an "atomic" clock that does this.)</p><p>On the topic of o'scopes, also back in the 70s, the Atomic Energy Commission had several different projects that each needed a <em>bunch</em> of high speed o'scopes, but since the actual use for them was only on the order of milliseconds, and they could be set up in a couple of weeks, what they did was to mount <em>hundreds</em> of them, each with a Polaroid camera, in a semi trailer that they could cart around to the various sites. (Each o'scope cost the equivalent of a new car at the time.) You can imagine how this made me drool when I saw it as an impoverished student!</p><p>Oh, BTW, two advantages of the copper plated steel: it's a <strong>LOT</strong> easier to solder to than either galvanized or aluminum (useful when you're doing point-to-point!), and it also has better electrical shielding properties than galvanized, though it's significantly more expensive (and harder to find).</p></p>
imabug on Introducing "Old Machine Time Machine"imabugurn:uuid:0135ec17-b430-30e3-9740-60239b914d6b2018-10-23T07:31:37-06:00<p>I was given a Heathkit IG-102 signal generator a few years ago that still works pretty well. Old Heathkit test gear is fun to play with</p>