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Does anyone sell an EMP-resistant tube radio these days?

Discussion in 'Ham Radio Discussions' started by KE0EYJ, Sep 26, 2017.

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  1. KE0EYJ

    KE0EYJ Ham Member QRZ Page

  2. N2EY

    N2EY Ham Member QRZ Page

    In a word: No.

    A short history:

    Until the mid 1950s, almost all ham gear was 100% hollow state, or nearly so. (There might be a 1N34A diode in the SWR or relative-power circuit, for example, and some use was made of selenium rectifiers.)

    Then solid state began to appear in power supplies. Silicon rectifiers replaced tubes. Zener diodes replaced VR tubes. Power transistors were used in DC power supplies (inverters) for mobile and portable use. Varactor diodes were used for RIT and similar applications. Small signal diodes were used for switching applications and as balanced modulators and detectors.

    As the 1960s progressed, more and more radios included SS devices in more and more roles. Bipolars and FETs were used in oscillator circuits. Transistors were used in the audio sections. ICs began to be used as well.

    By the 1970s, the point had been reached where most transceivers had only the driver and final stages as tubes - everything else was SS. By the mid-to-late 1980s, even those were replaced with SS.

    There were some pioneering efforts that violate the above timeline - it's just a general guide of how the mainstream changed. For example, the Hallicrafters FPM-200:

    http://www.radiolabworks.com/fpm200/fpm200.htm
     
    KG4RRH, WA7PRC, K9ASE and 2 others like this.
  3. W4NNF

    W4NNF XML Subscriber QRZ Page

    Vacuum tube equipment is certainly more resistant to EMP, no doubt about that. No, nobody is selling a vacuum tube radio designed to resist EMP events AFAIK. There are other means of protecting equipment, and that's usually the path taken these days--like placing the rig in a Faraday cage, hardening circuits in various ways and, if you think you will need to operate during an ongoing attack, using a self-contained power source.

    Want an EMP resistant tube radio, though? Head to the local hamfest and seek out a nice used rig. The main thing to look out for? Since the late 60s, much ham gear used some solid state components. That's not usually a killer, since transistors are far less likely to be destroyed than modern ICs and microprocessors. The degree of protection needed also depends on the EMP event you expect, whether it is a powerful solar storm on the low end, or a large multi-megaton RV detonated on the edge of space at the high end.
     
  4. WF7A

    WF7A Subscriber QRZ Page

    Isn't it folly to worry about EMP-proof ham radios? When you think about it, if you have the need of one then you have far greater problems to worry about than trying to reach other hams. (...and by the numbers, how many hams would also have EMP-proof radios to communicate with you?)
     
    KB9UWU, KU4X, WA7PRC and 5 others like this.
  5. KB4QAA

    KB4QAA XML Subscriber QRZ Page

    That would be an erroneous assumption. So is the assumption that solid state radios are not EMP survivable. The military hasn't bought tube radios in decades.

    EMP protection is largely based on good pulse protection systems, which are extensions of ordinary lightning/power pulse systems.

    Dept of Homeland Security guidelines attached.
    DOE EMP Resiliance Preparations Action Plan
    https://energy.gov/sites/prod/files/2017/01/f34/DOE EMP Resilience Action Plan January 2017.pdf

    p.s. If the power fails, I won't be fooling around with radios!
     

    Attached Files:

    N2EY and N0TZU like this.
  6. W4KYR

    W4KYR Ham Member QRZ Page

    Is there any truth that the Russians use tube radios in their Mig fighter jets to protect against EMP? If so, are these newer radios? Or older radios?
     
  7. WZ7U

    WZ7U Ham Member QRZ Page

    Ask Rocketman. He'll know. :rolleyes:
     
    WR2E likes this.
  8. KK6NOH

    KK6NOH Ham Member QRZ Page

    You have to be super careful what tube based rig you end up getting. Since vacuum tubes are no longer manufactured in this country you have to deal with existing stocks. Some tubes are more rare than others. Considering the law of supply and demand you could end up in a situation where you need a non existent or VERY expensive tube. A prime example would the the heathkit hw101 and its 6JS6 sweep tubes. They are expensive, rare, and fragile.

    After that you then also have to deal with aging components. It may work when you buy it and use it a while. But what about after you pull it out of storage after the carrington event? Pop a capacitor and you are up the creek. You could go through and replace all those old fragile components if you have the skills.... nothing wrong with that. Indeed I agree with W4NNF above when he said.....
    I would get a good rig that is more or less recent and build a faraday cage. Inside this cage you could also put in a solar charge controller and a nice stack of solar cells. I would also put a small but quality computer, copies of any emp sensitive car parts, any important data you might have that's on hdd's or ssd's, copies of any electronic entertainment of your choice, so on so on so on.
     
    W4NNF likes this.
  9. KB4QAA

    KB4QAA XML Subscriber QRZ Page

    Not in recent models. I was recently looking at Russian aircraft radio specs and they are quite sophisticated and comparative to western electronics. Not things you can do with tubes.
     
  10. WF4W

    WF4W XML Subscriber QRZ Page

    this may be a stupid question but has there ever been an EMP generated so that the effects on modern electronics can be measured? or is it theoretical?
     

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