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Messages - NJQA

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211
General Radio Discussion / Re: The Ultimate Pride Of China Portable Shortwave Radio for $9.59
« on: January 26, 2020, 1345 UTC »
Mine rattles.  The speaker is loose.  And there is a crack in the case.  You can’t get a quality $9.59 radio anymore <G>.

212
Utility / Re: CIS Navy on HF
« on: January 25, 2020, 2048 UTC »
A posting on eham claimed that the Chinese CW decoder is based on this:

http://www.ik3oil.it/_private/qst_cw.pdf

I have not verified whether that is true or not.

213
Utility / Re: CIS Navy on HF
« on: January 25, 2020, 2035 UTC »
There is this:

http://www.f6hoy.com/cw/

Or this:

https://youtu.be/PnJTHTvBUPg

Is that what you were thinking about?

214
VHF/UHF Logs, including satellites and radiosondes / Re: UHF mil air
« on: January 25, 2020, 1951 UTC »
I hear mil-air stuff.  I am sure there is a lot of traffic Chris can hear.

The 225-400 band is big and it is easy to miss stuff.  Maybe start with some power surveys to identify good target frequencies?  Try this:

http://kmkeen.com/rtl-power/


215
Equipment / Re: Wellbrook help
« on: January 25, 2020, 1857 UTC »
The big advantage to the FLX1530 is that it is easy to transport and store.  I can just imagine him purchasing one of the regular Wellbrook loops and putting it in checked baggage for the trip back to Jordan!  Some helpful baggage handler will probably bend it in half to save room.

The regular Wellbrook just uses the entire tube as a conductor.  It is not a shielded loop design where the tubing has a small gap at the top to expose the inner conductor.  There is no inner conductor.

I’m guessing that the FLX uses the outer braided shield of the short piece of RG58/LMR400 as the conductor and ignores the inner conductor.

216
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 25, 2020, 1118 UTC »
It has been a long time since JJY was on SW but they may have used something like two beeps/second there.

You don’t usually see AM or CW keying on VLF though.  The antenna BW (because they antennas are so short compared to the wavelength) is extremely small and it becomes difficult to build an efficient antenna that has a BW wide enough to support AM modulation.

On-off keying (CW) is also difficult, particularly at power.  I think JJY is a 50 kW station.  Keying a large load on and off is hard on the electrical system and the power supply.  Still, from what I read JJY does send a CW ID, so they apparently do that.  WWVB uses a modulation scheme that raises and lowers power.

Most VLF stations today use a MSK.  It is efficient, has a constant carrier, and works with antennas with narrow bandwidths.  I don’t know what JJY uses but MSK would be my first guess (and I emphasize that I am guessing.)




217
Equipment / Re: Wellbrook help
« on: January 25, 2020, 1049 UTC »
The antenna he is talking about (FLX1530LN) is a version of the Wellbrook that doesn’t come with a solid metal loop.  You hook up a short loop of either RG58 or LMR400 in place of the loop.

Performance (using good quality cable) should be very similar for either cable type.  You might find the LMR400 holds a circular shape better though.  You can find variants of LMR400 that have either solid and stranded center conductors.  The solid will also help hold a circular shape better, but this may not be a big thing.  You can always build a simple frame out of pvc pipe to hold the loop.

As far as the feedline between the Wellbrook and the radio, LMR400 will have less loss, but you won’t notice the difference at MF and HF frequencies unless you are using lengths far greater than 100 ft.  RG58 will be fine for most cases.  Try to stay with name brand coax - there are many Asian knockoffs that have poor braid coverage.



218
Amateur Radio / Re: Digital modes on HF... love it or hate it.
« on: January 24, 2020, 1243 UTC »
Don’t get me wrong - I think what K1JT has done with weak signal detection is amazing.  His work with EME software has made moonbounce possible for small footprint stations.  Ditto his meteor scatter SW.

I have no problem with his weak signal algorithms.  My problem has been with automation of the QSO process.  His implementation has the operators involvement being nothing more than clicking a button to log the QSO...and modified code is available that allows you to run in full robot mode.  I saw one of Joe Taylor’s presentations where he had a slide of suspected “robot” stations (based upon the fact that they ran 24/7), and I have seen the robot SW for sale on eBay.  The days of fully automated stations working each other have already started. 

If you ever find a first edition (circa 1983) copy of W9KNI’s book “The Complete DXer”, it is worth reading.  He has stories in it of tuning through the bands searching for DX, and puzzling out the rare and not so rare stuff.  It took some skill to find and work a rare one back then, and it was very rewarding when you were successful.  Today, with DX spotting networks, etc it is much more like shooting fish in a barrel. Now full automation has removed the last vestige of necessary operator skill. 

Maybe this explains some of the renewed interest in learning CW.  Maybe these are operators that are seeking some of the satisfaction you find in doing something difficult and succeeding...

Its like I said before: People don’t value things that come too easily.

219
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 24, 2020, 1124 UTC »
Not a trace of a signal this morning.  What was new was a RFI signal that wasn’t present the previous two mornings.  The VLF spectrum was remarkable quiet until about 0600 local when a wandering RFI signal started up.  It went away for a little while, and then came back.  I suspect a neighbor has a grow light or something...

220
Amateur Radio / Re: Digital modes on HF... love it or hate it.
« on: January 23, 2020, 1318 UTC »
The guys in the local club have grown tired of my rants about FT8.  I just go numb when I hear a newbie talking about making DXCC a month after getting his license...all on FT8.  They don’t know what they are missing.  The point is the journey, not the destination.  You don’t value things that come too easy.

CW however, has actually seen a bit of an increase among the new hams here.  I don’t know why, but some of our new hams have put forth the effort to learn and operate on CW.

At a VHF conference a little while ago I heard some of the contesters complaining about FT8.  The rovers in particular were having trouble raising stations to run through the bands because the home stations were parked on the FT8 frequency and had stopped scanning the bands.

221
22 Meter Band HiFER Beacons / Re: 22m Beacon
« on: January 23, 2020, 1224 UTC »
If you go to the K6FRC web site (see above) and click on the picture of his 22M antenna, you will see a picture of his transmitter.  He does very well!


222
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 23, 2020, 1203 UTC »
BTW, the magic time for an ID is 15 and 45 minutes after the hour when they send JJY in morse.

It is going to be tough to verify what I am hearing is actually JJY.  On the French and German time stations I was able to get a correct time decode using the Kiwi decoders, so I was confident of what I heard.  This signal is so weak that a decode would not be possible, even if the Kiwi JJY decoder worked (it isn’t operational yet).

223
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 23, 2020, 1151 UTC »
I listened again this morning.  You could just tell something was there — without the waterfall it would be unnoticeable.  Strongest fade in was at 1121Z.  I need to try again a little earlier.

Some of the guys in my local ham club have been working JA’s on 160 meters the past few days.  The solar minimum has been helpful for the low bands.
 

224
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 22, 2020, 1157 UTC »
I’ve got traces of a weak carrier on 40 kHz at 1152Z, but no where near strong enough to ID.

I’m using my KiwiSDR and a 1000 ft LOG.

225
Longwave Loggings / Re: JJY Japan 40 kHz Time Station 1140 UTC 22 Jan 2020
« on: January 22, 2020, 1148 UTC »
Which antenna were you using?

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