10M AM JUNKBOX TRANSMITTER

[@clytle374]

I love watching these. I'm too young to have been there. Lots of interesting circuits and designs mostly forgotten to time .

[@Derrick6162]

I'm glad that there are old timers out there that haven't forgotten where they came from, and are keeping the REAL essence of amateur radio alive. Thanks for sharing your knowledge.

[@MIKROWAVE1]

I remember where I came from. And I remember my parents saying there's probably nothing here in the North Country for you!

[@davidcampbell6527]

This is brilliant, Mike - choosing transformers by how manly they are! David.

[@MIKROWAVE1]

Build up your muscles and reach under the hamfester tables and pick up that iron!

[@cheesedoodlefeeder]

Another wonderful project in the true spirit of ham radio. "Build a transmitter!" So many other YT channels would rather just open a new box and or operate another appliance. Bravo to WU2D! 0:36

[@MIKROWAVE1]

Maybe I could do an unboxing of a cub scout screwdriver set.

[@m0dad]

Great timing for this project with all the activity. I love hearing the AM stations coming in from the USA here in the UK. Had some fun working 10m AM some years ago. Just happen to have started a 4 tube/valve AM transmitter for 160/80m. Looking forward to the nest video. I'm watching with interest. 73...David M0DAD

[@MIKROWAVE1]

It can only increase over the next year.

[@Guieno]

Hello mr. Murphy! I admire your hard work and energy! You are so quick with all these new toys, which I love very much. It warms me up in a foreign land. Greetings from Bulgaria! UR3QX 73!

[@MIKROWAVE1]

I would like to see some real Bulgarian home construction radio projects from the old days! Those transmitters had flavor.

[@nandrews8412]

Beautiful junkbox transmitter. 👍

[@MIKROWAVE1]

Well its not beautiful till it actually is wired and works!

[@maikerumine]

I love your grassroots and true to the arrt of radio, Mike. Keep on inspiring!!

[@MIKROWAVE1]

Thanks for watching some 1963 style homebrewin.

[@Steve-GM0HUU]

👍 Thanks for video Mike. Looking forward to seeing how this goes.

[@MIKROWAVE1]

I have to start wiring.

[@akdenyer]

Thanks Mike. I so miss people like you. Maybe catch you on CW again one day.

[@MIKROWAVE1]

Somebody is sending CW on 29 MHz. Nice QSO actually - dunno?

[@williamrmeara2162]

Really nice Mike. I have taken a very questionable path to 10 meter AM: I have modified some old CB radios. I have two working now. I will soon have a third. (I will give two away.) I regularly work into Texas from Virginia with just 4-5 watts. I have heard the UK and California. But my rig is a JC Penny! Oh the shame of it all! Your approach is much more uplifting. 73 Bill N2CQR

[@youtubeaccount931]

Can't wait to see your build!

[@W1RMD]

Timtron (W-YAY one YACHE Yell R) has plans for using an old tv power transformer as a modulation transformer that looks pretty cool, although those are getting harder to come by. I like the modular approach to building this in stages, breaking this down to sections you can test individually for us less experienced in building. I guess the trick is to not be afraid to experiment a little, or a lot. The 6au6's might be getting harder to find with USAGI building his computers with 100's of them! I love that little tube as a preamp as they sound great! As long as you don't get zapped, you live to build again. I know purists prefer 5u4's or 5r4"s but solid stating the rectal- fryers is the way to go! Great project. I can't wait to see this progress, and if it doesn't work out, you can always talk to Bert using scream modulation!

[@MIKROWAVE1]

Both IRB and HENRY YELL ARRRRR were some first mobile contacts for a youngster in his very first car with a old NCX-3 Mobile attempting to do AM-ish operation. I have used Filament transformers as Modulation Transformers, so I have no doubt that old power transformers, especially those with dual primaries or HV secondary's with liberal feedback should not work as modulation transformers.

[@clytle374]

Him using up so many 6au6s kinda pisses me off. I bought a JAN case on a sale a few months back as insurance for the HW-101s I rebuilt.

[@MIKROWAVE1]

The 6AU6 pentode is neither a fantastic audio tube nor analog or digital computer tube. It's just a good general purpose low frequency IF tube. They were made in the Billions. If I slipped and fell in the shack, I likely stepped on a 6AU6 rolling around! ;)

[@W1RMD]

I was really bad when he dropped a board on the floor containing DOZENS of them! Several didn't survive. :(@@clytle374

[@StevenFell-nu4db]

Yeah, AM angel music my favourite mode!

[@richardbrobeck2384]

Nice video 10 meter is great !

[@chrisscott1547]

What a trip back to 1968!

[@MIKROWAVE1]

Every Sunspot cycle brings some AM and FM activity out of the woodwork.

[@cidcolead1115]

I scored an old Harvey Wells Bandmaster Senior. It will be awhile before I am back in the states to get it going. It is an oscillator/multiplier chain with a plate modulated 807 designed for a carbon mic. Your videos gave me the confidence to pick this up.

[@MIKROWAVE1]

She's a Beauty all right!

[@migsvensurfing6310]

You make some interresting awesome videos.

[@MIKROWAVE1]

Thanks for watching!

[@multilecful]

Sounds exciting im in. Was going to convert a marine CB Australian but i think i have most of the high ticket items from my guitar amp building days.

[@akdenyer]

I am at work but will try and take a listen tonight.

[@johnwest7993]

This video reminds me about the newbie ham KZbin channel where they were referring to a kit rig they were running as "homebrew." I pointed out to them, (as diplomatically as possible,) that kits were referred to as 'kits', and that homebrew meant that the ham had designed and built all of, or at least some part of whatever gear they were discussing. He got offended. I suspect he now considers me to be one of those old farts who thinks they own all of ham radio, and I won't allow anything in my shack but old rack-mounted AM rigs for 160 meters, that I spend all my time on the air talking about my feet, and disparaging new hams and digital modes. The fact is that I was just trying to help him learn the proper terminology for what he was discussing so his audience wouldn't be forever confused about what others were talking about. It probably didn't help that a month or so earlier I'd left a comment explaining that the 'second' harmonic was not referred to as the 'first' harmonic just because it was the first harmonic he saw above the fundamental. I do wish the FCC would make it clear to new hams that a ham license does NOT make a newbie the ultimate authority on all things RF, and that a ham license isn't a 'super-CB' license, but an invitation to learn about RF and the communications hobby. There's a reason the FCC has granted even Tech Class hams the authority to design, build, and operate 1.5 kW EME stations, although I'm not really sure if many of the new hams actually know they have that authority. These folks desperately need Elmers, though I'm not sure they even know what an Elmer is. We definitely have our work cut out for us with these new KZbin channels run by novice hams. They don't realize that they are looked upon as teachers, and the responsibility that carries along with it. It doesn't help that they simply see us as troublesome old coots who are standing in their way, and are stuck in our old habits.

[@MIKROWAVE1]

Let me explain the difference between Maritime Mobile and Marine Mobile :)

[@radiodf]

My first W6 contact years ago as a kid, was on a converted Fanon Courier CB walkie w/ about 3W. BTW, FM on 29.60 is GREAT fun. Repeater outputs on 29.62> ; W5DFW in TX on 29.66, and HD9HD in Switzerland on 29.65, are heard regularly here in W1 land.

[@MIKROWAVE1]

Stephanie, you are the ultimate technician, Radio Conversion Artist, radio hacker (before there were radio hackers), good stuff hoarder and recycler, mobile aficionado, mobile antenna and scanner freak. etc...

[@MrShotlighter]

Oh how I wish I had your junk box............or my junk box, before we moved house 25yrs ago!

[@MIKROWAVE1]

They're always after me JUNK BOX!

[@Tom-W7TMD]

I have been wanting to see one of these builds! If I can find a chassis I will try to build along. I don't have a junk drawer full of parts so will have to purchase them.

[@MIKROWAVE1]

The Magic is sourcing a good Power Transformer like 375 to 400VCT at 200 mA and with a 6.3V 4A winding for the filaments like the Hammond 290 YX. This would allow a full wave bridge and half the V on the Center tap in the classic Economy-style power supply with a choke input filter. It even had a bias winding. The exact mod iron I used is on Ebay.

[@MIKROWAVE1]

www.ebay.com/itm/256344724532?hash=item3baf561434:g:~BoAAOSwafdlJwuR&amdata=enc%3AAQAIAAAA8OXtWwgGr%2BAmPfLajoPeHdiLWaGIH6G%2FB%2FHnMmWpkuGQqyr2iyxCzLtnT%2FrADMDsD%2Buot5ilGz9rOyIYJ5rkpnMrkyNGrqwqPdaLy8MXD%2BNgh9uK%2FGmYH%2BUOs2Ae%2FPjwRyrK8WCJIKbP9WgxrBoavmN%2B4sqi0LqzDxAfT59nP8qSqNWRQ%2FHqCVLXHUQPJ13oREpHAULrqvwKLoeFbTL81qJsWkM9sKL8B2gqxW%2BWG0ZbTzoN%2BK38VHupCAg1xq1hF8Vm8A2lGZG47Z338%2BS%2FOKufR1JtvyAm3xAnVKYlbHyoXMXeqgbBa%2FH8ZMUMPnPeLQ%3D%3D%7Ctkp%3ABk9SR9i_pq6XYw

[@vincenzofidanza2539]

That's a great way to do , I agree

[@vincenzofidanza2539]

Hello Mike thanks for your replay , I suggest you include this option in your transmitter mods to overcome difficulties in being able to obtain a modulation transformer.

[@MIKROWAVE1]

There are many tricks to get AM on the cheap with what is available!

[@JCWise-sf9ww]

I like your junkbox transmitter project using Push-Pull plate modulation. Question where can one buy a 50 watt rated plate modulation transformer for 6L6 tubes? Hammond Manufacturing only makes a 25 watt modulation transformer. A ham friend of mine wants to complete his 100 watt transmitter and can't find a transformer.

[@MIKROWAVE1]

Aside from hamfests, I see several candidates here: www.ebay.com/itm/275896909165?hash=item403cbcbd6d:g:GGcAAOSwDMZkhNnv&amdata=enc%3AAQAIAAAA8OH8reRkSXZ%2BlosBL1%2F1VdnqejQP5Ex3WERAQB6HFYRcQsbUUfebVaWa7n0AAPZyNv0kix%2BKfHKBqPywIjYwFXHmBX%2FwTCjPl8MD%2B6VhsY7OMP9hyIvK8lIewEiJxm41FsXlBauI6%2FWbqeH8dRpdlPvV6RswMi0PB5I178bGqSVGr2%2FXi0KSkIV5ueqmuGVSeETuJtymv52bXRDti%2BwhMVjBQyfAG5WByGv0v9HjyhSowa7uGwBLP58VKwkm%2B73D1xyoUXKEwjmHbZswWMN10%2Fk2xi8a0fa1z1aANTs%2BmP6lwmTR1wgNSDCDUeJ3AH3GCQ%3D%3D%7Ctkp%3ABk9SR4KX1eKEYw

[@MIKROWAVE1]

This looks like an Apache transformer. pair of EL34s or KT88s or 807s to modulate a pair of 6146s.

[@vincenzofidanza2539]

Modulation transformers are difficult to find. Any high voltage power transformer with 5v and 6.3v windings could be used in reverse, ex. an IC gain clone like the LM3875 (60w) which output feeds the lower voltage windings could work decently in an AM as a modulator.

[@MIKROWAVE1]

I actually used a 5A 6.3 CT power transformer in reverse driven by a conventional push pull set of IRF840 mosfets interstage driver transformer driven from a LM380 to modulate an ARC5. I did hook it up modified Heising however to relieve the transformer of DC current saturation. With a bit of feedback, sounded great .

[@MirlitronOne]

I have yet to hear AM on 10m but I had my first long-distance AM QSO on 15m last week.

[@MIKROWAVE1]

Yeah the bands have been good. But about every third week the sun goes nuts and kills the bands for a couple of days. That happens too.

[@XPFTP]

hahha i turn on 29,010 and boom... ragchewers on am .. think its the 1st i heard anyone on 10m am lol just as i watch this video 1247pm est

[@MIKROWAVE1]

The nice thing about 10M is that the signals are either there or they are not.

[@gretalaube91]

Yay! And don't forget 10 FM! 73 W3IHM

[@MIKROWAVE1]

Yes that is really popping too.

[@ajfogertyfan8245]

Wish there were more AM on 10 meters, yes the band is wide open most of the day, often virtually world wide at times, but generally very little activity on AM heard, CQing rarely brings any responses. 73 de Chris AJ1G

[@MIKROWAVE1]

G8NOF blasting in today at 11AM 29.01.

[@lampshadesneeded]

so are there any construction plans for this?

[@MIKROWAVE1]

The Mikrowave1 Radio Resources support page on FB includes the schematic and details.

[@m0kov]

Whenever I've contemplated building a plate modulated transmitter the stumbling block has always been getting hold of a suitable modulation transformer. Having rewound quite a few mains transformers I've often wondered about the possibility of winding my own. Has anyone tried, or does anyone have any suggestions? Steve M0KOV

[@MIKROWAVE1]

Over here you can still find them at hamfests, mostly military surplus. The ugly little silver 100W (50W) transformers out of the venerable BC-191 or BC-375 were 5 dollars for many years . The TCS iron shown i the video were all over and still can be found. An the magic ART-13 Mod Transformers defy physics. Here's' a typical 2:1 www.ebay.com/itm/175621059388?hash=item28e3d4b33c:g:IxgAAOSwOdlj8n5L&amdata=enc%3AAQAIAAAA8HEjxF9dtQdN31LDLrdpiTu31zTOKJiO1cAYAOgekbyc0AKud1pxVP0UcXQn7b8HxIJnGyZgfmJZId5ezoj3cuF3afzBAOi0sM1HX6W887PgCwnQxKxLtXq7PcT7qUIUNRluWyOdyV7x%2BYn%2B4FWo4%2FwjL%2BzvNJHEBD4nmLseJKWxP5m3QmBSxkow1WaMDRbTMTw1ZTcNfxajgvQO1XgMMcoSm4CGBmdKn8Zg9%2Bv%2F9cFUKe6ldjG%2FPH35pekzuU0GOFZ6Wf%2FUnyGCI9w%2BcfF%2FoNXmJBDTHvWcm2e2q7pZlIO4SDYj2JLiPxjzaZnAGoQxqQ%3D%3D%7Ctkp%3ABk9SR6KPhNmEYw

[@Capecodham]

AM can only be used in the morning (AM).

[@ornithopterindia]

👍

[@whippoorwill1124]

Looks like 400 V shorted to ground at 7:29. "That's not right" - Austin Powers ;-D

[@MIKROWAVE1]

BOOM! Yes and that was not a clumsy edit either. It came that way!

[@nickking8317]

I think I’m going to have to start repairing stuff and hoarding stuff to salvage coz this rabbit hole is pricey.

[@MIKROWAVE1]

Junkbox = no ordering new expensive stuff. Terminal strips, small parts sure, but Transformers are way too expensive.

[@paulswift700]

10m is the only band I can use fir AM here in Thailand but there is never anyone on😢😢😢

[@MIKROWAVE1]

Get a little CB Beam, cut it down a bit to 10M, and get it up in the air and you will hear some activity.

[@Capecodham]

fir?

[@daviddavidson1372]

Been hearing alot of 10m am on 29.000 mhz. Loud into nc

[@MIKROWAVE1]

Yes hearing a lot up here too!

[@usuthu65]

Hi Mike - fantastic as always. I'm probably ruining it by typing this, but 2E26 surplus tubes are 10X cheaper than 6146s now. Not sure why, but there you have it. 73 de W1PJE

[@G7VFY]

G7VFY 1st