Handbook Novice Transmitter Part 1

I Found a classic homebrew Novice Transmitter at the Ham Flea that is exactly built to the ARRL Handbook 1956-1964 Instructions! Let's take a look and see what we can do to get it on the air. This was also my first home built transmitter project attempt in 1973, so I am familiar with the set.

[@LkOutMtnMan]

I built the 10W version using that same power supply except mine had a 6v6 final for 40M. I had just gotten my General so I loaned it to a friend who had his novice ticket. He bragged on the transmitter working so well. I saved up $100 and my dad drove me to Bessemer Al to Ack Radio to buy a used NC190 receiver. Lot of money for a 14 yr old back then.

[@williamrmeara2162]

Oh man, this made me order some NeverDull for my HQ-100. I got a laugh out of your search for the fuse. I did the same thing yesterday with the HQ-100. No fuse! So I put one in. I always thought that the big RF choke at that antenna output was a brilliant, life-saving idea. In 1974 I was given an HW-32A. It felt light. No power supply. Guys in the club looked at me like I was dumb and told me to "just go out and find an old TV." I did. Somehow, I survived. Thanks for the great video Mike. 73

[@MIKROWAVE1]

It's fun to resurrect these old boxes; and the homebrew rigs are especially exciting depending on the "artist".

[@user-mp7hi5rt8e]

Glad you did this video. I built one in junior high electric shop as a novice in 1967 (with lots of assistance). It worked fine. A little bit of chirp if I remember. I STILL have it! 7173! WA6CAB

[@MIKROWAVE1]

Nice! Wow I am glad to hear that so many of you guys built these!

[@KG5IF]

The AR3 was my first receiver and I bought it at a downtown amateur radio shop in Houston. All I had was 15.00 and they wanted more but the manager took pity on me and it went home to east Texas and it provided many hours of pleasure.

[@W1ZB]

I was at Nearfest on Friday but didn’t see you. Great find. Use it in the Novice Rig Roundup. 73 OM

[@MIKROWAVE1]

Sorry I missed you J. I was walking only on Friday, and half dull from flying in from a Vegas Trade Conference the night before.

[@Steve-GM0HUU]

Mike, treating us yet again to another enthralling series. $10 for the transmitter is amazing. Worth it even for a few of the components - not that I would condone part stripping such a beautifully constructed example. More than once, I have rescued an item from a hamfest (we call them radio rallies) and have not been able to bring myself to break it up for parts. Providence ensured that this one found a good home.

[@MIKROWAVE1]

Many of the homebrew carcasses are half finished. People sometimes gave up halfway in. Fair game!

[@whippoorwill1124]

Thanks for this series Mike. From the colour of the cover, your copy of ARRL's The Radio Amateur's Handbook looks like the 41st edition, from 1964. FWIW the project appeared unchanged as A Three-Band Oscillator Transmitter for the Novice, every year from the 35th edition of the Handbook in 1958 until finally in the 42nd edition of 1965. The design was by the late Lew McCoy, W1ICP; it was first published in QST of December 1957 as A Three-Band One-Tube Novice Transmitter. All those Handbooks, and the QST issue, are available (legitimately) as free PDF downloads from the worldradiohistory site.

[@acestudioscouk-Ace-G0ACE]

I love the history which put into these videos, educational and entertaining. Thanks for taking the time to make all your excellent videos.

[@michaelmiller641]

Interesting video! I've got the 1959 arrl handbook, which is now quite well worn! And I notice that circuit is in it!

[@MrShotlighter]

We seen to be traveling down parallel memory lanes! I'm currently getting the parts together for a 6AG7/807 cw transmitter. Just been diverted though, by the acquisition of a Codar AT5 at the weekend. Looking forward to part 2 of your restore, as todays video was an unexpected & pleasant surprise. 73 de Nigel G8NYZ

[@BillyLapTop]

Wow! This brings back some memories for sure. My first ARRL Handbook was the one you displayed from 1964. My friend and I built 2 of these units, a variation of this transmitter based on the handbook for 40 meters only. We used parts from mostly televisions and console radios from the 1940's and 1950's that wound up on the curb during "Junk Week" in Clifton, NJ during the springs of the late 50's and early 60's. We even ran into the Xtal current problem you mentioned. I can recall burning myself touching the FT-243 crystal. Left a blister. Yeh, a hot radio and a learning experience. Thank you for taking the time to produce this series. I'm looking forward to the rest this radio's story.

[@chuckcrizer]

What a tease! Looks good though. Looking forward to the next video. I love these types of tube rigs.

[@MIKROWAVE1]

Its coming for Wed.

[@superhet7281]

Great stuff, Mike! “Just gimme $10 and take it away.” I LOVE IT when that happens! ;-) I’ve got one of those too, but I think it got “souped up” at some point in its history. I’ll have to dig it out.

[@MIKROWAVE1]

Foreshadowing - I souped mine up too. After cracking a couple of crystals.

[@N9CQX]

Great subject. Wonderful presentation. You present your points very clearly and concisely. Many other videos on ubee tubee I rate as being well below your quality camera/audio work. I'm sure you have seen others who are obviously very versed in electronics but have no idea as to how to do a decent video. They fumble and mumble through with a handheld camera and w/o editing or making sure no unwanted noises like barking dogs or babies crying are not included. Too bad that KZbin found it necessary to interrupt with a manhood deficiency commercial. Harry

[@PeopleAlreadyDidThis]

That’s a neat find. A friend insisted I take a huge power supply, transmitter, and modulator he’d scrounged, apparently built from “The Radio Handbook” in the late 40s-early 50s. It uses an oscillator, buffer, and PA topology. It’s missing the PA tubes, and I haven’t tried to determine what they are-certainly bigger than 811’s-but it’s all reminiscent of this little rig of yours. Wish it was as solid! I look forward to seeing this one come to life.

[@MIKROWAVE1]

That is very typical of the main transmitter setup in the 40s. Might use 304TLs or even 813s!

[@terry5089]

What a great find. Those HC49 crystals have crummy frequency stability if you run much current through them due to heating. Long before they crack. I haven't tried one with the 100 Ohm resistor in series. It will be interesting to see how that experiment goes.

[@MIKROWAVE1]

Whoop Whoop! We shall see and sacrifice to the crystal gods.

[@radiodf]

That was also one of my first transmitters when I was licensed as a Tech in 1976. The circuit was in one of the old ARRL Handbooks that was in my HS Library. I made the transmitter as part of a project for Metal Shop. I used a chassis from a Halicrafters S38(?); as it had all of the same power supply components. I think the only part that I needed to buy was the 0V3 VR tube. BTW, theres a QRP version in a Nov/Dec'77(?) 73 Amateur Radio Magazine that used a 6AQ5 audio beam amp tube. WA1YKL

[@MIKROWAVE1]

Same but I had a power supply already for my ARC-5 made from TV parts. So my whole transmitter fit in a Heathkit VTVM box! But no regulator tube and I cracked a few crystals!

[@davidportch8837]

Looks great Mike...amazing find... also rally looking forwards to see whether you can get a modern crystal to work with this. I have been thinking about building a valve TX for some time but never got around to it because of difficulty in obtaining old Ft243 type crystals etc...

[@MIKROWAVE1]

We shall see David. Part 2 hitting Wed.

[@adzbasslines268]

Nice work Mike! I'm keen to see how it turns out. I'm especially interested in using the modern crystals. I bought a whole bunch of FT-171B's and found many of them had their internal quartz replaced with HC49's! How you prevent them from being overdriven is something I'll follow closely!

[@mohinderkaur6671]

use a 2n2222 xtal oscillator with the hc49 to drive the tube

[@MIKROWAVE1]

And fit the entire assembly in the FT-243? Challenge accepted?

[@PapasDino]

You mean he didn't say "Worked last time I plugged it in"? I honestly thought you were going to say that you bought back your own transmitter! I built a ASCII to Baudot converter way early in the digital/computer games and ended up selling it at a hamfest...fast forward probably 10-15 years at a another hamfest I saw a box that looked awfully familiar and it still had my old call sign on the front panel in glorious DYMO label maker. I just had to buy it back for nostalgia sake! ;-) 73 - Dino KLØS

[@MIKROWAVE1]

Actually this one would not have worked since I found the main coupling cap lead was broken. Dymo maker YES how many of these had those? Once they set on with Nicotine after 40 years, they really get a nice patina.

[@Gordonseries385]

👍

[@vincei4252]

Hey, as it's almost impossible to find those PI wound 2.5mH chokes used in a lot of these transmitter circuits is it be practical or ill advised to use a modern 2.5mH inductor, say the switch mode or power inductor style devices that you can buy from Mouser or Digikey in its place?

[@MIKROWAVE1]

Nothing more rabid than a confident novice. Take a look at my video about "Choking on Radio Projects?". Also beyond winding your own, which is completely practical, some folks like to use Type 75 material toroid's or those 470 uH -1mH bobbin core jobs from Mouser in series.

[@clytle374]

Good to hear crystals are becoming available again. Someone in particular?

[@MIKROWAVE1]

Apparently some guys out there are ordering in large enough quantity to pass on the savings for the HC-49/U on the popular ham frequencies! They have never been cheaper, considering 2022 dolllars.

[@clytle374]

@@MIKROWAVE1 awesome. Yes 1963 dollar is officially worth $21 in silver today, but if you actually want that 1oz silver $28. Luckily I haven't needed a crystal for the hw-101 yet, they are far from common nowadays

[@garypoland5288]

The guide pin portion of the tube base break very easily, I have done it myself when wrestling with inserting tubes in new sockets, especially some that are made in China.

[@greggaieck4808]

Mikrowave1 your Transmitter that you. Bout is cool my hobbys are painting pictures and lisining to shortwave and ssb iam thinking about getting my ham license I have 4 shortwave receivers me and my cousin are going to a Swap meet June 5th 2022 Sunday morning at 8 am

[@MIKROWAVE1]

Greg, it has been a month now. Do you have your ticket yet? Ha.

[@W4BIN]

The loss of vacuum does not show in vacuum tubes, the air (replacing the vacuum) oxidizes the metallic getter material sputtered on the inside of the envelope (mirror) to a white powder stuck on the inside of the glass. Ron W4BIN

[@MIKROWAVE1]

I see that powder on some of the broken ones!

[@mohinderkaur6671]

simple work around. Just use a 2n2222 oscillator to drive it!

[@MIKROWAVE1]

We may have to go there - still playing here.

[@menotworking]

I've recently been doing some work with one-tube transmitters, and I'm finding they are much more crystal-friendly than their reputation, with the right component values and voltages. For example, I've had a 6AU5 sweep tube putting out 10W on 40 meters with an HC49 crystal, with no chirp. The three things I do are (1) remove the grid-cathode capacitor entirely, just using the tube capacitance. On 80 meters this may not work, but it always works for me on 40 and up. (2) lower the grid leak R. I found that, for the 6AU5 at 10W out, a value of 6.8k was optimum for power out and low stress on the crystal. Yes, 6.8k, not 68k. I wire a 25k pot in for the grid resistor and adjust for max power, then replace with an equal or slightly greater value fixed resistor. Values like 47k turn out to be way too high. (3) reduce the screen voltage to the minimum needed for the desired power output. With 300V on the plate of the 6AU5, I only need 110V on the screen for 10W out. Keeping the screen voltage as low as possible (for a given power output) keeps the crystal excitation to a minimum. Then just peak both the TUNE and LOAD caps for maximum power output. I haven't tried above 10W out since my power supply pretty much falls over above that level (around 20W input).

[@MIKROWAVE1]

One big secret is to use a lower voltage regulator on the screen of the pentode or on the plate of the triode. When you run them at 200 to 350V, that is where the crystal current can really get high. Yes output power will suffer a bit.

[@menotworking]

@@MIKROWAVE1 I can get 10W output from a 6DQ6-family sweep tube with only 50V (!) on the screen (350V on the plate). I know it sounds fantastic, but it's true. 5W zeners are great for screen regulation at lower voltages. Peak output grid resistor value with that tube is only 2.4k. I've found that the lower grid resistor value also reduces harmonics. That 10W transmitter has the 2nd harmonic down 47dB, well below the legal limit. If I increase the resistance, the power goes down and the harmonics go up.

[@scharkalvin]

not a good idea to double or triple in the final, or oscillator that is directly driving the antenna. Should run the final stage straight through to avoid harmonics and sub-harmonics being radiated. Guide pins were most likely broken off by accident, and not removed on purpose. it's rather easy to break them off when removing a tube and 'bending' it in the socket, usually when a tube is all the way in the back of a TV set and hard to reach this will happen.

[@MIKROWAVE1]

The FCC wrote me a note and they seemed to agree with you. I had a nice signal on 20M they said.

[@DAVIDGREGORYKERR]

Taking the tube out of the family TV could result in you being left homeless so better to purchase the tubes also would be better to operate at 1AM if your parents will let you during the school holidays and at any other time move to flea power so as not to annoy the neighbour.

[@MIKROWAVE1]

Guilty again! I keep forgetting to replace the tubes in the big RCA set before mom gets to her "As the World Turns".

[@fourfortyroadrunner6701]

For some reason photos of S-38's keep showing up. Hallisrapters should have their collective a$$s kicked for EVER marketing such a nonsense radio (AC-DC) to young would be hams, not only for the poor performance, but for the electrical danger. I had one, as well as a Heath AR-2 or 3, and even though the performance of the Heath was not light years better, it WAS some better, and hundreds of volts (LOL) safer. My first attempt at a tx was a sweep tube oscillator and I had put the plate bypass on the wrong end of the plate RF choke!!! I quickly abandoned that miserable crystal breakin' ho and went with a 6AQ5/ 1625 on 80/40.

[@MIKROWAVE1]

I agree that much equipment component quality, production wiring and circuit practices were all over the map to keep prices low. The sad face of a kid with a broken crystal blank after opening the FT243 - been there.

[@VujadinGrujic]

Sta mi vrede ovi komentari kada nisu prevedeni,

[@MIKROWAVE1]

Vrijedi ih staviti u Google prevoditelj!

[@Capecodham]

I will double your money

[@MIKROWAVE1]

That is exactly what Vegas said.