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Amateur RadioI got my first ham license in October of 1970. WN6EPS. The "N" meant Novice. Back then, Novices had somewhat more restricted privileges than today: we were 75W DC Input, crystal controlled CW transmitters on three little tiny frequency bands. 80M, 40M, and 15M. Truly we were legion. You'd get on 40M after school, it'd be solid CW from one end to the other. Some had nice storebought transmitters, some had homebrew; chirp-chirp, click-click. Heck even some of the store-bought transmitters did that. The 40M novice band was the ultimate test of a receiver; if your receiver and its operator could get through that, you could do anything. The most popular rigs were the Heathkits; the DX60B transmitter, and the HR-10B receiver. Oh, and they had a CW transceiver, too. Such high-class equipment was alas beyond my means; My first attempt to get on the air was with a homebrew one-tube transmitter. It had a 6V6 tube ( this was normally an audio power output tube: I believe it was a Beam Power Pentode ). The output PI network was wound on a cardboard toilet-paper tube and a neon bulb was used for the output indicator. The whole thing was built on a baking tin that I stole from my mother. DC input was supposed to be 10 Watts. After saving a bit, I obtained a 50's vintage DX-40 transmitter and a National NC-240D receiver. The NC-240D was a strange beast; National's engineers didn't believe in bandswitches; the HRO had plug-in coils for changing bands. So they took all the plug-in coils, put them in a box, put the box on rails inside the chassis, and used a knob to push the box back and forth. Contacts on top of the box connected each stack of "plug-in-coils" to the variable condensor array. (Yes, they were called "condensors" back when the receiver was built ). My log from the first few months of operation shows a preponderance of "CNS" ( Call Not Successful ) entries. I'd thrown a longwire antenna over the house, and built a tuner to make it work. And I had not the slightest idea how to tune that tuner. Even with an SWR meter, it was possible to tune the thing to dump all or most of the power somewhere else than into the air, and that is what I managed to do. The first two pages of the logbook show 52 "CNS" entries, and only 10 actual contacts. Then things changed drastically. Two things happened:
O why couldn't #2 have happened before #1? Would have saved me fifty bucks :-). And so I was off. Went down to the San Francisco Customhouse in March of 71 and got the General license: WA6EPS, passed the Advanced test in October. At first, I made do with the DX40. I'd find SSB people calling CQ, zero-beat them, and call them on AM. People mostly didn't know the difference, although one guy did tell me my balanced mixer was out of whack. Of course, a new General couldn't stick with the old Novice rig, so I went out and found some SSB equipment. Moved the old NC-240D out in favor of a Hallicrafters SX-122. Got a "Trio-line" transmit setup. "TRIO" was the name that Kenwood used in Japan. The "Trio line" was a 10W SSB transmitter with a matching 200W linear. Not being content with a mere 200W, I built a second linear in an ARC-5 cabinet. This one had four TV sweep tubes stuffed into that little box. The one time I tried to run it without a fan, it burst into flames! At any rate, I wound up with the TRIO exciter feeding the TRIO amplifier, feeding my homebrew amplifier. I stuffed all of this stuff, along with the SX-122 receiver, into the headboard of my bed! To change bands, I had to tune three PI-networks, peak two exciter tune knobs, and synchronize two VFO's, not to mention retuning the antenna tuner. I didn't change bands much. I had a headset with a boom microphone and the transmitter had VOX. Used to lay in bed until five in the morning yacking on 40M SSB. Probably fried myself pretty good with all the RF from that homebrew linear :-). Now I have an early-eighties vintage TS-830S, a 30L1 linear and odd assorted 2M FM rigs, TNCs and gadgetry. Still not really cutting-edge stuff. The above was written in the mid-90's. Now it is 2012. After a long hiatus, I got back on the air. The TS-830 is alas long gone, so I bought a TS-590. Still have the 30L-1, but got a deal that I simply could not refuse on a nice Alpha 78. The '78 has come down in price to more or less ordinary mortal levels because people worry about the tubes. It uses three little ceramic 3CX400A7 triodes. Priced a 3CX400A7 lately? Yeah, RIGHT. Just in case the tubes ever die, I obtained a bunch of 3CX400U7's on ebay. Those are electrically the same tube, but have a coaxial "socket", which I will have to fabricate if I ever want to use them. I used to dream about using a computer to analyze and synthesize radio waves. While I was dreaming, others were doing, and now SDR is a reality. Bought a SDR transceiver kit, put it together, got it working. Still haven't made any contacts with my bone-crushing 1/2W. :) Digital modes have come a long way since I was last on. It's simply amazing to me that they can stuff a whole ham band into the space of one SSB signal. Back around 1981 or so, I tried to hook my TRS-80 up to the ham radio. It made so much RF hash that the ham bands essentially disappeared. And my wife even complained from the living room. "Stop that, I can't watch TV!" Now I run a cheap old laptop with approximately One Zillion Times the processing power right next to the rig, and you can't even hear it. So some more years have gone by. It's now 2022, and the bands are starting to come alive again. After a several year hiatus, I got back into ham radio last year or so. For some reason, my interest always seems to peak at the bottom of the sunspot cycle. Go figure. It started with a question on Quora: "Are there any ham radio kits anymore?". Somebody answered authoritatively that no, there weren't, that Heathkit was long gone. I thought "really?" and started websearching. I found a semi-kit called the "Ubitx", bought it, put it together, and started operating. Then wanted a bit more power, and built my "Tiny Linear" - which is a multiband HF linear outputting on the order of 100W. It used a cheap Chinese amplifier card and an LPF from an Icom 756PRO. And a little touch screen left over from the Ubitx project( long story ). I also built a 40M CW transceiver called the "QCX" from Turkey. Wonderful full-breakin CW, but no AGC. I was operating field day, and a local came on and almost blew me off my chair :). I also started making contacts with my Softrock SDR card - with the help of the Tiny Linear. But I got tired of all the wires and cables draped across the desk. The SDR card showed me that I *really* wanted something with a bandscope. Wow - look at that loud signal down there! Let's go take a listen... So I obtained a Yaesu FTDX10. Yeah, the UI is strange, but wow does it have ears! Built a bigger linear... my "Medium Linear". 400W out with a pair of MRF300 LDMOS devices. They're ostensibly 300W apiece for 600W output total, but that's only if you completely don't care about linearity. The Medium Linear operates with a Huawei cell-phone-tower power supply. It has a little screaming fan, so the supply is remote mounted in a wooden box under the bed. The box is lined with 1/4 inch sheetrock for fire safety. The linear itself is built into a case from a 1960's vintage Heathkit "Single Bander" SSB transceiver. News flash: The Medium Linear has been obsoleted by the Bigger Linear. The Bigger Linear has a single MRF1K50N device. Imagine - a single device the size of three postage stamps laid end to end - rated for a kilowatt and a half of CW! It's powered by the same Huawei PS as the Medium Linear, and achieves output of a hair over a kilowatt on SSB. The case is made of stock sized sheets of 1/8" thick aluminum, bolted together on aluminum angle stock. The heatsink is vertical, and sticks out the back. Almost the entire back of the linear is heatsink. |