I think that you hugely underestimate how many tubes and crystals it would take to replicate the QMX's basic radio functions, even neglecting any of the computer-control interfaces, IQ outputs, etc..

?

If you are concerned about EMP events knocking you off the air buy yourself an old Collins S-line or an FT-101 and have at it;? they have a great user interface, too.? Add a model 19 mechanical teleprinter to include RTTY capability.?

?

?

73, Don N2VGU

Hi Everyone.? Having just successfully built a QDX, with a QMX "on the way", I have a question for Hans and the Group.? The QRP-Labs radios are all fantastic, and Hans is a certified genius.? However, we all live in a very tumultuous world, and the very real possibility exists of our radios becoming useless from an EMP blast (whether man made or cosmic).

?

I would love to build a transceiver, similar to the QMX, but instead of EMP susceptible integrated circuits, step back in time a bit and use vacuum tubes (valves).? A modern radio design utilizing low power tubes instead of ICs.? It would certainly be larger than what we have now, but I'll trade size for heavy duty reliability any day.?

?

What do you think?

?

73,

Roger K1VB

? ?

Well mate ,,? with all that? EMP blast you 'd be? better off with lead line underwear so your essential parts don't become useless like the hypothetical? Semicoductor issue.

For? a? Prepper radio that could stand a Hiroshima level bomb? 7 km away ,? look up on of the myriad? 6T9 or? 12 AE 10 single tube? 7 W? valve transmitters that infest the internet.? You'd have to? coordinate the crystal frequencies with your other? doomsday preppers though.?
you could? go for a? version of the? Taurus? 3362 based receiver (40 mtr version)? and have quality superhet Rx to match it? $26 as a kit from India? ( but where you get your latter filter xtals from is a worry as nobody sells filter sets these days ) that? could go in a little tin lined box with steel shielding outside .

Even if you are succumbing? to lethal doses of? Gamma radiation? ,as you pass out it will be a comforting thought that your glass and lead transceiver will be working long after you have passed on.?
HOld that thought - Getting mains power for the Tx? after the Big one drops on you might be a bit of an ask.? Solar panels of course will be hit by your proposed EMP pulse.

Diplomacy sounds the best option but? cans of? baked beans and dried seeds in lead lined rappers are a back up.?

?

Trust But Verify.

? Namely Verify that Donno is not doing the diplomacy by himself I think.? (as Sleepy Joe walks off the stage in to oblivion).?

Best? wishes in Prepperdom from Nz.

Well I agree with original poster Roger K1VB

It would be wonderful to build an all-tube transceiver with SSB and CW capabilities; I'd love to do that. Just don't expect me to produce a kit for it! Or do it any time soon (not a trivial project!).?

73 Hans G0UPL

On Wed, Jul 24, 2024 at 12:58?AM Timothy Fidler via <engstr=[email protected]> wrote:

Well mate ,,? with all that? EMP blast you 'd be? better off with lead line underwear so your essential parts don't become useless like the hypothetical? Semicoductor issue.

For? a? Prepper radio that could stand a Hiroshima level bomb? 7 km away ,? look up on of the myriad? 6T9 or? 12 AE 10 single tube? 7 W? valve transmitters that infest the internet.? You'd have to? coordinate the crystal frequencies with your other? doomsday preppers though.?
you could? go for a? version of the? Taurus? 3362 based receiver (40 mtr version)? and have quality superhet Rx to match it? $26 as a kit from India? ( but where you get your latter filter xtals from is a worry as nobody sells filter sets these days ) that? could go in a little tin lined box with steel shielding outside .

Even if you are succumbing? to lethal doses of? Gamma radiation? ,as you pass out it will be a comforting thought that your glass and lead transceiver will be working long after you have passed on.?
HOld that thought - Getting mains power for the Tx? after the Big one drops on you might be a bit of an ask.? Solar panels of course will be hit by your proposed EMP pulse.

Diplomacy sounds the best option but? cans of? baked beans and dried seeds in lead lined rappers are a back up.?

?

Trust But Verify.

? Namely Verify that Donno is not doing the diplomacy by himself I think.? (as Sleepy Joe walks off the stage in to oblivion).?

Best? wishes in Prepperdom from Nz.

Heck, I have a venerable old Yaesu FT-101 up in my office. It has a weird audio gain problem I don't know how to diagnose, much less fix. The mechanical stuff I manage to take care of, like replacing the planetary gearbox for the main tuning vernier, and the funky thing used for the preselector. I found new/old stock replacements on eBay and figured out how to install them, and it was working great, until this problem cropped up.

If I leave it on for a fairly?long time, a minimum of an hour, at some point the audio just falls to half its original volume. The receive audio amp seems to be the only part affected -- transmitting has no issue, for example. If I turn it off and let it cool down, the audio is back to?normal. I'm thinking there's either a capacitor that's going leaky when it heats up, or maybe a tube is going. Doing a retube and recap job on the thing scares the ever-lovin' pee-waddins out of me, but I'll either do it, find someone to do it, or junk it if it isn't worth fixing. Thing is, I really love the FT-101. It's the radio I fell in love with in the 70's, when a CB operator friend got one that had been modded for 11 meters. He had a massive Moonraker 6 antenna on a tower in addition to a Starduster vertical. (I tried to talk him into using the Anixter Mark V sleeve antenna, but even though his partner worked for Anixter, he just couldn't warm to it. So *I* got the Anixter Mark V -- his partner got me one for a song -- and we put it on the garage roof. It was the single best CB antenna I ever had, with gallons?of gain.)

That FT-101 just screamed RADIO!!!?to me, and I dearly loved visiting them and using that radio. Was it illegal? Yup. Did I care? Not much, no. But when I got a chance to buy one for a pretty darned good price, I jumped at it. I had just gotten my Extra, and was excited and wanted to give myself a gift. Except for this one weird trick it insists on doing, it's a great radio. But right now, it's sitting up in my office, waiting for me to learn how to fix it. I'm not sure I'm ever going to get there, though. I may have to ask someone else to help me with it.

I had an ancient WWII receiver that reputedly was a Navy unit from either a ship or a plane. I'm thinking ship, but only because the plane would have to be a monster to haul this thing around. It was 80 or so pounds, and that's only the receiver. I never got my hands on the transmitter. The biggest issue I have with that memory is that I don't know what make and model it was. I've looked at hundreds, maybe thousands of pictures, and can't find it. That radio got me into SWL, like the Yaesu FT-101EE my friend had. (Mine is just an FT-101. No E, no EE, no Z. Just an FT-101.) I used to go to sleep listening to classical music from a dozen different countries. I learned to love the BBC, Voice of America, and others. I adored a local AM station, WQXR, that was relatively close to where we lived on Long Island. It moved to FM a while back, and is now available via streaming. They've even got an app, which I have. The music is still wonderful.?

But that's a bit of my history with those old radios, and even if I'm not going to gut an old "parts only" radio and build a QCX+?or QMX+?into it, and a Baofeng or something for VHF/UHF, the memories of what those radios meant to me when I was young are still sweet.

-=-=-=-=-=-=-=-=-

73,

Gwen, NG3P

Heck, I have a venerable old Yaesu FT-101 up in my office. It has a weird audio gain problem I don't know how to diagnose, much less fix. The mechanical stuff I manage to take care of, like replacing the planetary gearbox for the main tuning vernier, and the funky thing used for the preselector. I found new/old stock replacements on eBay and figured out how to install them, and it was working great, until this problem cropped up.

If I leave it on for a fairly?long time, a minimum of an hour, at some point the audio just falls to half its original volume. The receive audio amp seems to be the only part affected -- transmitting has no issue, for example. If I turn it off and let it cool down, the audio is back to?normal. I'm thinking there's either a capacitor that's going leaky when it heats up, or maybe a tube is going. Doing a retube and recap job on the thing scares the ever-lovin' pee-waddins out of me, but I'll either do it, find someone to do it, or junk it if it isn't worth fixing. Thing is, I really love the FT-101. It's the radio I fell in love with in the 70's, when a CB operator friend got one that had been modded for 11 meters. He had a massive Moonraker 6 antenna on a tower in addition to a Starduster vertical. (I tried to talk him into using the Anixter Mark V sleeve antenna, but even though his partner worked for Anixter, he just couldn't warm to it. So *I* got the Anixter Mark V -- his partner got me one for a song -- and we put it on the garage roof. It was the single best CB antenna I ever had, with gallons?of gain.)

That FT-101 just screamed RADIO!!!?to me, and I dearly loved visiting them and using that radio. Was it illegal? Yup. Did I care? Not much, no. But when I got a chance to buy one for a pretty darned good price, I jumped at it. I had just gotten my Extra, and was excited and wanted to give myself a gift. Except for this one weird trick it insists on doing, it's a great radio. But right now, it's sitting up in my office, waiting for me to learn how to fix it. I'm not sure I'm ever going to get there, though. I may have to ask someone else to help me with it.

I had an ancient WWII receiver that reputedly was a Navy unit from either a ship or a plane. I'm thinking ship, but only because the plane would have to be a monster to haul this thing around. It was 80 or so pounds, and that's only the receiver. I never got my hands on the transmitter. The biggest issue I have with that memory is that I don't know what make and model it was. I've looked at hundreds, maybe thousands of pictures, and can't find it. That radio got me into SWL, like the Yaesu FT-101EE my friend had. (Mine is just an FT-101. No E, no EE, no Z. Just an FT-101.) I used to go to sleep listening to classical music from a dozen different countries. I learned to love the BBC, Voice of America, and others. I adored a local AM station, WQXR, that was relatively close to where we lived on Long Island. It moved to FM a while back, and is now available via streaming. They've even got an app, which I have. The music is still wonderful.?

But that's a bit of my history with those old radios, and even if I'm not going to gut an old "parts only" radio and build a QCX+?or QMX+?into it, and a Baofeng or something for VHF/UHF, the memories of what those radios meant to me when I was young are still sweet.

-=-=-=-=-=-=-=-=-

73,

Gwen, NG3P