7 ms·

IMO, when the last LW transmitter shuts down, the whole band needs to be reallocated to hams. Realistic small-ish antennas are shockingly doable with a capacita

IMO, when the last LW transmitter shuts down, the whole band needs to be reallocated to hams. Realistic small-ish antennas are shockingly doable with a capacitance hat, loading coil, and counterpoise.

yakkers 3mo ago
There’s still a lot of utility stations in the LF/longwave band. Particularly time signals (WWVB in the US, ALS162 in France, DCF77 in Germany, JJY in Japan, etc.) and NDB beacons. At least in VK/Australia, there’s the 2200 meter band, but it’s quite limited (1W power limit, CW/digital only, 135.7–137.8 kHz). At the same time, as much as I don’t want the AM broadcast band to die, I’d love an amateur band in the lower/middle part of MF/MW.
- bilegeek 3mo ago
  > There’s still a lot of utility stations in the LF/longwave band. Particularly time signals (WWVB in the US, ALS162 in France, DCF77 in Germany, JJY in Japan, etc.) I meant just the broadcast band 148.5-283.5 kHz. (Though I'd love if 2200m and 630m were just a bit wider.) > and NDB beacons. Good point[1]. So 148.5-200 kHz in ITU Region 2 (and keep LowFER allowances on 160-190kHz as a consolation prize.) [1]https://www.dxinfocentre.com/ndb.htm https://www.dxinfocentre.com/ndb.htm
- ErroneousBosh 3mo ago
  In the UK we have 2200m but it's 1W *ERP*, so you're probably running a good couple of kW to get there with any practicable aerial. We've also got a chunk just off the bottom of MW around 475kHz, which ought to be good for long-range night-time communications. It's licenced for CW, QRSS, and narrow-band digital modes.
- pfdietz 3mo ago
  > Particularly time signals Doesn't GPS utterly replace this?
  - rafski123 3mo ago
    Many wall clocks and wrist watches (Casio WaveCeptors) plus cars set their times from radio.
  - mrob 3mo ago
    Longwave penetrates buildings better than GPS and is harder to jam.
  - ballooney 3mo ago
    In no way whatsoever, for low power devices.
toxik 3mo ago
I hate to rain on your parade, but a lot of interests want the low-frequency spectrum. It will absolutely never be allocated to amateur radio.
- K0balt 3mo ago
  What are they wanting to build? It’s hard to put much information on lower frequencies, afaik?
  - wartywhoa23 3mo ago
    I bet it will have to do with the military, almost inevitably.
    - hylaride 3mo ago
      With the risks to GPS becoming more acute, many jurisdictions are seriously entertaining bringing back a modern version of LORAN. There's also high frequency firms that want to muscle their way into shortwave frequencies as they can have lower latency between trading sites (eg NYC and Chicago) since the physical infra isn't a direct link as the crow flies (as well as the speed of light being slowed in fiber optic lines). They've even restarted some microwave links, as they don't necessarily need a lot of bandwidth, just latency.
      - K0balt 3mo ago
        LORAN was actually pretty awesome.
  - deleted 3mo ago
    [deleted]
- ErroneousBosh 3mo ago
  It's not really much use for anything. What "interests" would you think are interested in it?
- 7402 3mo ago
LeoPanthera 3mo ago
"Longwave" has no universally agreed defintion, but good news, amateur radio already has usage of 135.7 kHz to 137.8 kHz. Building equipment that works on frequencies this low, and avoiding natural interference, can be extremely difficult.
- ErroneousBosh 3mo ago
  Building aerials that work efficiently at 136kHz is difficult (although I have a croft that's approximately long enough for a half-wave dipole in NW Scotland, close to the sea for a good groundplane). Actually generating the signal you could do with a moderately expensive USB soundcard, directly synthesizing it with simple VST-like plugin. Mad to think about, really.
microgpt 3mo ago
I thought hams already had plenty of bands. Is there not one in this range?
- aeonik 3mo ago
  There is a very small slice that amateur radio gets in this band, in theory it would be nice to have a bigger slice, but honestly, building antennas for this band to transmit anything worthwhile would be pretty hard. My 7 Mhz antenna (HF, 40m band) is 67 feet long, and goes across by whole house. The smallest antenna you could get away with for LF would be hundreds to thousands of feet long. You might be able to go smaller if you enjoy suffering. Though, there are some pretty creative antenna designs that defy logic.
  - microgpt 3mo ago
    Does stapling it to your neighbours' fence lines and painting it like the wood count as creative? I wonder if you can couple to your local distribution grid, and not get arrested.
    - aeonik 3mo ago
      I just string the antenna across my attic. Coupling into my power upstairs is a bit of a problem sometimes though. Pirating power is something I've heard that happens, but I looked it up, and couldn't find an actual cited example of someone doing it via induction. Plenty of people doing it via extension cords and device tampering though.
      - ErroneousBosh 3mo ago
        > Coupling into my power upstairs is a bit of a problem sometimes though. I haven't worked with my end-fed on 40m for a couple of years. We've recently all had our crappy old aluminium-cored BT lines replaced with shiny new fibre though, so this time I am unlikely to lift the coveted Worked All DSLAMs trophy ;-)
      - microgpt 3mo ago
RobotToaster 3mo ago
Best we can do is privatisation and selling it to a party donor.
- xattt 3mo ago
  LW-HFT all the wayyyyy! - some cryptobro /s
  - ErroneousBosh 3mo ago
    That'd be quite a challenge! From a quick Google I see that HFT carries out trades in an average of 700ns, which is close to the cycle time of a 150kHz carrier, so you'd have to come up with some really clever phase modulation scheme that could carry meaningful data in *one single cycle*. You're definitely going down the SDR route for that.
    - WorldMaker 3mo ago
      It's still technically "high frequency", just in terms of sound rather than trade volume. Also if it's some cryptobro's pet project it probably needs time to settle on some blockchain ledger, so extra reason to find a new meaning for "high frequency" like sound wave cycle to confuse the marketing on the project.
wartywhoa23 3mo ago
The witness of the conspiracy practice in me says that the opposite is more likely to happen in the world whose govenments strive to limit its ineterconnectedness and turn it into a set of isolated anclaves not unlike Orwell's Eurasia, Eastasia and Oceania. The next logical step in that direction would be cracking down on HAM, not liberalization of it. We'll see.
- inquirerGeneral 3mo ago
  [dead]

yakkers 3mo ago

There’s still a lot of utility stations in the LF/longwave band. Particularly time signals (WWVB in the US, ALS162 in France, DCF77 in Germany, JJY in Japan, etc.) and NDB beacons. At least in VK/Australia, there’s the 2200 meter band, but it’s quite limited (1W power limit, CW/digital only, 135.7–137.8 kHz). At the same time, as much as I don’t want the AM broadcast band to die, I’d love an amateur band in the lower/middle part of MF/MW.

bilegeek 3mo ago
> There’s still a lot of utility stations in the LF/longwave band. Particularly time signals (WWVB in the US, ALS162 in France, DCF77 in Germany, JJY in Japan, etc.) I meant just the broadcast band 148.5-283.5 kHz. (Though I'd love if 2200m and 630m were just a bit wider.) > and NDB beacons. Good point[1]. So 148.5-200 kHz in ITU Region 2 (and keep LowFER allowances on 160-190kHz as a consolation prize.) [1]https://www.dxinfocentre.com/ndb.htm https://www.dxinfocentre.com/ndb.htm
ErroneousBosh 3mo ago
In the UK we have 2200m but it's 1W *ERP*, so you're probably running a good couple of kW to get there with any practicable aerial. We've also got a chunk just off the bottom of MW around 475kHz, which ought to be good for long-range night-time communications. It's licenced for CW, QRSS, and narrow-band digital modes.
pfdietz 3mo ago
> Particularly time signals Doesn't GPS utterly replace this?
- rafski123 3mo ago
  Many wall clocks and wrist watches (Casio WaveCeptors) plus cars set their times from radio.
- mrob 3mo ago
  Longwave penetrates buildings better than GPS and is harder to jam.
- ballooney 3mo ago
  In no way whatsoever, for low power devices.

toxik 3mo ago

I hate to rain on your parade, but a lot of interests want the low-frequency spectrum. It will absolutely never be allocated to amateur radio.

K0balt 3mo ago
What are they wanting to build? It’s hard to put much information on lower frequencies, afaik?
- wartywhoa23 3mo ago
  I bet it will have to do with the military, almost inevitably.
  - hylaride 3mo ago
    With the risks to GPS becoming more acute, many jurisdictions are seriously entertaining bringing back a modern version of LORAN. There's also high frequency firms that want to muscle their way into shortwave frequencies as they can have lower latency between trading sites (eg NYC and Chicago) since the physical infra isn't a direct link as the crow flies (as well as the speed of light being slowed in fiber optic lines). They've even restarted some microwave links, as they don't necessarily need a lot of bandwidth, just latency.
    - K0balt 3mo ago
      LORAN was actually pretty awesome.
- deleted 3mo ago
  [deleted]
ErroneousBosh 3mo ago
It's not really much use for anything. What "interests" would you think are interested in it?
7402 3mo ago

LeoPanthera 3mo ago

"Longwave" has no universally agreed defintion, but good news, amateur radio already has usage of 135.7 kHz to 137.8 kHz. Building equipment that works on frequencies this low, and avoiding natural interference, can be extremely difficult.

ErroneousBosh 3mo ago
Building aerials that work efficiently at 136kHz is difficult (although I have a croft that's approximately long enough for a half-wave dipole in NW Scotland, close to the sea for a good groundplane). Actually generating the signal you could do with a moderately expensive USB soundcard, directly synthesizing it with simple VST-like plugin. Mad to think about, really.

microgpt 3mo ago

I thought hams already had plenty of bands. Is there not one in this range?

aeonik 3mo ago
There is a very small slice that amateur radio gets in this band, in theory it would be nice to have a bigger slice, but honestly, building antennas for this band to transmit anything worthwhile would be pretty hard. My 7 Mhz antenna (HF, 40m band) is 67 feet long, and goes across by whole house. The smallest antenna you could get away with for LF would be hundreds to thousands of feet long. You might be able to go smaller if you enjoy suffering. Though, there are some pretty creative antenna designs that defy logic.
- microgpt 3mo ago
  Does stapling it to your neighbours' fence lines and painting it like the wood count as creative? I wonder if you can couple to your local distribution grid, and not get arrested.
  - aeonik 3mo ago
    I just string the antenna across my attic. Coupling into my power upstairs is a bit of a problem sometimes though. Pirating power is something I've heard that happens, but I looked it up, and couldn't find an actual cited example of someone doing it via induction. Plenty of people doing it via extension cords and device tampering though.
    - ErroneousBosh 3mo ago
      > Coupling into my power upstairs is a bit of a problem sometimes though. I haven't worked with my end-fed on 40m for a couple of years. We've recently all had our crappy old aluminium-cored BT lines replaced with shiny new fibre though, so this time I am unlikely to lift the coveted Worked All DSLAMs trophy ;-)
    - microgpt 3mo ago

RobotToaster 3mo ago

Best we can do is privatisation and selling it to a party donor.

xattt 3mo ago
LW-HFT all the wayyyyy! - some cryptobro /s
- ErroneousBosh 3mo ago
  That'd be quite a challenge! From a quick Google I see that HFT carries out trades in an average of 700ns, which is close to the cycle time of a 150kHz carrier, so you'd have to come up with some really clever phase modulation scheme that could carry meaningful data in *one single cycle*. You're definitely going down the SDR route for that.
  - WorldMaker 3mo ago
    It's still technically "high frequency", just in terms of sound rather than trade volume. Also if it's some cryptobro's pet project it probably needs time to settle on some blockchain ledger, so extra reason to find a new meaning for "high frequency" like sound wave cycle to confuse the marketing on the project.

wartywhoa23 3mo ago

The witness of the conspiracy practice in me says that the opposite is more likely to happen in the world whose govenments strive to limit its ineterconnectedness and turn it into a set of isolated anclaves not unlike Orwell's Eurasia, Eastasia and Oceania. The next logical step in that direction would be cracking down on HAM, not liberalization of it. We'll see.

inquirerGeneral 3mo ago
[dead]