[600MRG] WAS Emergency Traffic on 630m NOW: I dunno - general complaining about the state of MF and LF???

Tue Nov 30 17:37:19 EST 2021

Boy we are about to creep way off Warren's original topic :-)

> I suppose if an emergency were declared, 630m might be restricted to
> emcommm for the stricken area.  So Winlink would be OK.

I suppose that is possible but I seriously doubt it would ever be on
the table to actually happen for many of the other reasons previously
discussed.  I just don't see it happening.

But, getting back to the point of equipment:

Between Kenwood, Elecraft and Icom, there are plenty of radios that do
a great job making low level signals and have good, capable receivers
but its almost like the manufacturers hide these facts when they could
really be using them as selling points.  Elecraft is really the only
one that makes any effort to take advantage of it but even they miss
the mark.  People are often surprised that the newer Kenwood or Icom
radios operate at 472.  This came up recently with a new station that
is using an Icom.   Icom doesnt even bother to mention not to run the
power up because the output is dirty above drive level.  Or that you
need an external low pass filter..so that is one point that has to be
fixed going forward but in general its off manufacturer's radar.  I
don't know how that gets fixed so people know that their radios
generate a signal that can be amplified...Responses are rare when a
conversation attempt is initiated.

And then there are amplifiers to be paired with these drive level
rigs.... K5DNL shuttered his amp operation at the beginning of the
year and while there are still plenty of plans out there on the
internet for a wide variety of great amps in addition to offerings by
G0MRF and that kit operation out of VK, people *seem* unwilling to
build or even assemble.  It's not everyone but people I encountered
regularly pre-2020 would always comment that they might give it a try
once they could go over to HRO and put down their card and buy a turn
key station.  Of course, we are still waiting on them and will be
waiting for them for a long time....

Probably the closest thing to turn key and bullet proof is the monitor
sensors transverters but the common complaint there is that its
pricey.  There ain't no free lunch...  Stuff costs what it costs.

After transitioning to the Rig Expert, I realized that my modified MFJ
was never much more than an antenna dipper.  Getting further away from
50 Ohm's meant that the numbers were meaningless so trying to make
calculations and decisions were a shot in the dark.  I found that with
the numbers from the Rig Expert, however, I could actually develop
networks that were in the ball park enough to respond to a reactive
antenna and make it work.  I'm sure today the nanoVNA is the successor
and touts even better results.  Always more do-dads...

The act of resonating and matching is easy enough when following the
procedures and not cutting corners on materials and "the process"...
But that's the trick...  too many won't follow those step and then
they give up and that is one less signal on the air with a workable
signal....

yes, I've let this rant devolve into complaining at this point
somehow.  I do hope a few more prospective ops will take the plunge
this season, take a chance and build something and get on the air.
There are a lot of sharks circling for new blood...  There are also
plenty of guys willing to help.  You just have to ask.

73... I'm done... Warren got more than be bargained for ;-p

John..

On 11/30/21, Ed Cole <kl7uw at acsalaska.net> wrote:
> John,
>
> OK, just a couple more comments:
> I suppose if an emergency were declared, 630m might be restricted to
> emcommm for the stricken area.  So Winlink would be OK.
>
> Emcom organizations would provide the digital stuff and one would only
> need the antenna, 630m equipment, and a radio with computer I/F.
>
> My K3 operates on 630m at mw level via the transverter I/F board and my
> modified NDB Beacon drives at that level to provide 100w into 50-ohm.
> My antenna loading coil matches 50-ohm to 20-ohm antenna resistance at
> 630m.
>
> I modified a MFJ-269B to work at 400-800 Hz so merely connected it in
> series with the ground and bottom end of the coil.  Moved the antenna
> tap until there was minimum reactance (that turned out with R=20). If
> you have strong nearby broadcast stations, they can affect the meter.  I
> was lucky that 920 KHz was the only local AM station.  I recently bought
> a new MFJ-269D which covers 100Hz to 470 MHz.
>
> I found the 50-ohm tap by watching the MFJ connected to the coax and
> moving another tap (about 2 turn above ground.  Bird 43 Meter with 100H
> element shows good match, though underreads power.  I have a RF ammeter
> on the NDB transmitter to set output (1.4 amps-rms at 50-ohm).
>
> The K3 needs the upgraded synthesizer boards to operate below 490 KHz.
> K3s and the new K4 have that as standard.
>
> Since the NDB operates with xtal control one only needs to drive at
> under mw levels (I pulled the XOSC and coupled with a 0.1 uF disc
> ceramic cap.  The first driver past the BP coil (adjustable 250-500 KHz)
> is a 2N2222.  The NDB is a Southern Avionics unit (I bought surplus for
> $40).
>
> 73, Ed - KL7uW
>
> On 11/30/2021 11:18 AM, John Langridge wrote:
>> Hi Ed,
>>
>>> I think most of the HF emergency comms are using a digital mode.  That
>>> would work on
>> 630m but how much spectrum would it occupy on 630m?
>>
>> Yes, a lot (but not all) of that is using Pactor and Winlink,
>> particularly when operator resources are limited.  Because of BW
>> requirements I've also avoided opening that pandora's box.
>>
>>
>>> CW
>>> would be simple but running a digital mode more useful as text could be
>>> printed at either end.
>>
>>
>> yes, but this operation I described was intended to be a simple
>> exercise without a bunch of hardware and interconnects to "borrowed"
>> transceivers or laptops.  Im not much of a digital op anyway...
>>
>>
>>> Biggest challenge for 630m is the antenna.  A 40-foot high T would be no
>>> more challenge than setting a HF antenna during FD.  Ground radials
>>> would probably take the most effort/time.
>>
>> Yes.  The physical setup is not so much an issue, but radial setup in
>> the heat or cold could be a factor.  The real issue seems to be the
>> fundamental understanding of R and X and being able to follow the
>> simple steps to both resonate and match an antenna.  I can't tell you
>> how many hams just can't keep from looking at an SWR meter instead of
>> following what is happening with R and X on their analyzer as they
>> make adjustments.. it turns a 5 minute exercise into one that is 20
>> minutes or more.  I've watched it happen on many occasions...But
>> antenna related issues are probably the #1 complication followed by
>> #2, which is readily available equipment or "ready to go, out of the
>> box" hardware.
>>
>> Anyway, this is all probably off topic from Warren's original
>> questions.  Warren, I'm not aware of a single instance under part 97
>> rules where hams have been called to use 472 for emergency traffic but
>> the potential is there and the core guys on the air every night could
>> get it done if they were called to action.
>>
>> 73!
>>
>> John..
>>
>>
>>
>> On 11/30/21, Ed Cole <kl7uw at acsalaska.net> wrote:
>>> John,
>>>
>>> This experience repeats what Laurence-KL7L and I did the summer of 2012
>>> as experimental licensees on 495-KHz
>>>
>>> I would transmit 100w at the transmitter with est 4w EIRP and Laurence
>>> would receive it about 70 miles north showing 35 dB above noise solid
>>> signals every time.  We sked at noon every Saturday for most of the
>>> summer.
>>>
>>> I was using a 43-foot high by 130-foot inverted-L with two parallel
>>> wires separated 2-foot.  I had three radial of 2-foot chicken wire laid
>>> on the ground 50 to 70-foot long.  Fourth radial was my 120-foot run of
>>> 1-5/8 inch hardline from support tower to the house (shield grounded at
>>> both ends).
>>>
>>> That 50-foot support tower came down in high winds a year ago so I
>>> decided to run my 80m dipole with ladder line strung at 40-foot in a T
>>> configuration with ladder line shorted and fed by a large base coil
>>> (essentially the same antenna as you used).  Things didn't get done this
>>> year.
>>>
>>> I plan to run a 40m dipole at right angles to the 80m dipole feed point
>>> so both will act as top loading the T configuration.  I plan to "plant"
>>> up to 8 radial wires in the lawn by splitting the sod with an axe and
>>> pushing the wire into the slot that results.  Hope to have that working
>>> by end of next summer.
>>>
>>> I think most of the HF emergency comms are using a digital mode.  That
>>> would work on 630m but how much spectrum would it occupy on 630m?
>>>
>>> Biggest challenge for 630m is the antenna.  A 40-foot high T would be no
>>> more challenge than setting a HF antenna during FD.  Ground radials
>>> would probably take the most effort/time.
>>>
>>> 100% reliable range should extend to maybe 200-miles (or more?).  CW
>>> would be simple but running a digital mode more useful as text could be
>>> printed at either end.  I was involved in professional emcomm at my
>>> workplace 1994-2009 (Head of Comm dept.).
>>>
>>> 73, Ed - KL7UW (ex WD2XSH-45)
>>> http://www.kl7uw.com/630m.htm
>>>
>>> On 11/30/2021 9:54 AM, John Langridge wrote:
>>>> Hi Warren,
>>>>
>>>>
>>>> About 3 years ago KE7A and I exchanged radiogram traffic on CW between
>>>> one another at field day.  At the time we were about 100 miles apart
>>>> and we were both using a Monitor Sensors transverter (50w), bucket
>>>> coil (that went to WM3M after the event) and a ladder line fed dipole
>>>> that this particular club's field day site was using on their CW
>>>> station.  I temporarily configured it as a Martconi T, about 40 foot
>>>> tall with just a very minimal number of radials.  I would have to look
>>>> at my notes for estimated EIRP but it was very low but there were no
>>>> problems in passing the traffic, even with summer noise and storms
>>>> that were in the area, as I recall.
>>>>
>>>> We exchanged three pieces of traffic and I used it as a topic for a CQ
>>>> article on tactical comms on 630m.  UTC notification had been
>>>> submitted for the site of the exercise about 6 months prior.
>>>>
>>>> I can tell you that it has been a hard sell to the traffic folks since
>>>> it requires a little more effort than the typical plug and play ham
>>>> radio and we really aren't doing anything on the mechanical side in
>>>> software...  It's just good old-fashion radio.
>>>>
>>>> I can't say that this exercise  had any influence but I was encouraged
>>>> to see the RRI folks talking about prospects of doing the same
>>>> scenario on 160m  using the same type of setup just a few months after
>>>> my article went to press.  SO perhaps there are some "baby steps" at
>>>> play.  I should have followed up at the time and asked a few more
>>>> questions to them but I did not.
>>>>
>>>> Traffic handling is changing a lot and has been for quite some time.
>>>> I tried to offer this exercise from the perspective  of just another
>>>> tool in the bag for a traffic handler that wanted to be really
>>>> prepared.  Whether it hit home or "stuck", I can't say.  As a
>>>> semi-regular op on a state level CW traffic net, I can tell you that
>>>> no one has ever asked me to QSY to 630m to pass a piece of traffic but
>>>> I would be happy to if they ask.
>>>>
>>>> So in summary, we did it on 630m to show it could be done with minimal
>>>> hardware and that value could be realized from doing it (in this case
>>>> the recipient received their traffic).  Had there been a real
>>>> emergency, we could have done it.  Ground wave was stable and strong
>>>> enough and we didn't have to compete with QRO stations during the
>>>> field day period on HF to send the same traffic.  Obviously no
>>>> emergency in this case, but like most traffic nets, they are training
>>>> opportunities.
>>>>
>>>> Just my perspective.
>>>>
>>>> 73,
>>>>
>>>> John KB5NJD..
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On 11/30/21, Warren Ziegler <wd2xgj at gmail.com> wrote:
>>>>> It's been some years now since U.S. Amateurs have been allowed to use
>>>>> the
>>>>> 472-479 KHz band. The justification was that it would be useful for
>>>>> emergency traffic. Just wondering how many of you have handled
>>>>> emergency
>>>>> comms on 630m? If so, can you provide details on the nature of the
>>>>> emergency and why you chose 630m to pass the traffic?
>>>>>
>>>>> Tnx & 73 Warren K2ORS
>>>>>
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