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Messages - Quietguy

Pages: [1] 2 3 ... 11
1
General Discussion / Re: 3.818MHz Net on Sunday nights
« on: November 14, 2017, 06:39:18 PM »
BTW - is there a place to look up SW transmission information? That is a list of transmitters on the air.

Several, one is http://www.short-wave.info/, which shows HLL Seoul Meteorological Radio (Korean, Japanese, English, Chinese) on 5858 kHz or R.FARDA in Persian on 5860 kHz.

There are also smart phone apps with schedules.

Wally

2
Tactical Corner / Re: Loss of Water
« on: November 07, 2017, 06:36:21 PM »
Nice!  I worry about it handling the pressure of house water, but something like that has a lot of potential.  We don't plan on being in this house more than 5 more years, so this idea is for the next house.

One option is to not connect it in-line with the house supply, but put a 12 volt RV pump on the discharge outlet and back-feed it into the house system as needed.  Close the main supply valve from city water so you aren't trying to feed water to the whole neighborhood.  You can use a garden hose to make a temporary connection from the RV pump to a convenient hose bibb, with appropriate freeze protection as needed.  That should be good enough for sanitation purposes.

A non-permanent installation like that could be done in a day and the whole thing moved with you to your next location.  Or, leave it behind as a rain-water collection system for the garden.

Wally

3
General Discussion / Re: Have you tried the 160m band?
« on: November 03, 2017, 09:35:50 PM »
What do you think? Try it? Don't bother?

I haven't had an antenna up yet I could tune on 160, but I had a single eye-opening experience with it.   A few years ago I was running NVIS Pactor tests on 80m with some friends, and one wanted to try his NVIS antenna on 160.  He was about 100-ish miles north of me and running maybe 50 watts or less.  I knew I couldn't tune to connect but we decided to see if I could hear his call.  I was switching antennas and had the incoming antenna coax disconnected from the LDG antenna coupler, which was connected to the radio with about 15 or 20 feet of coax.  I was on the telephone with my friend when he hit the connect button early, and damned if his signal didn't couple to my IC-706MkIIG through that 20 feet of coax and my radio tried to answer.  Of course the SWR was through the roof so I hit the power switch to shut down the radio but I was in disbelief over that - his NVIS antenna was one of those run-along-the-fence-top affairs about 5 or 6 feet off the ground.  I don't know how long it was, but it put a strong signal into my radio through maybe 20 feet of coax as an antenna.

Ever since then a 160m antenna has been on my list of things to do since I have the space.  But, physical problems have kept me from doing any antenna work for some time now, so it is still just "on the list".

Yes - try it.  Otherwise you will never know.

Wally

4
General Discussion / Re: Lost at sea 5 months without comms
« on: October 31, 2017, 08:11:19 PM »
The plot thickens, as RadioRay would say.  At least I think RadioRay would say that.  Now they admit having an EPIRB, but never activated it:

Quote
During the post-incident debriefing by the Coast Guard, Jennifer Appel, who was on the sailboat with Tasha Fuiava, was asked if she had the emergency beacon on board. Appel replied she did, and that it was properly registered.

“We asked why during this course of time did they not activate the EPIRB. She had stated they never felt like they were truly in distress, like in a 24-hour period they were going to die,” said Coast Guard spokeswoman Petty Officer 2nd Class Tara Molle, who was on the call to the AP with Carr.

[snip...]

Experts say some of the details of the women’s story do not add up.


www.foxnews.com/world/2017/10/30/sailors-lost-at-sea-for-5-months-never-activated-emergency-beacon.html

I'm no sailor, but something smells fishy to me.
Wally

5
General Discussion / Re: 3.818MHz Net on Sunday nights
« on: October 10, 2017, 12:21:14 AM »
They're sure proud of that unit! Did I really see them for $1500? I'm looking at the County Comm setup.

They have been discontinued but there is currently one on ebay for $200 Buy-It-Now.  I have had one for years and I like it, but I can't imagine anyone paying $1500 for one.  The CountyComm GP5-SSB is a nice little receiver, but the TH-F6A is a tri-band (2m/1.25m/70cm) handheld transceiver with wideband receive coverage - a completely different thing.

Wally

6
Net Activity / Re: Global Radio Relay Network
« on: August 28, 2017, 07:58:44 PM »
This is the main issue in traffic handling groups, all of them, getting people on the air at the right time, regularly.

Peer to peer digital works extremely well.  Given power availability - doable with solar - allows 24/7/365 monitoring and message capture.  I have done it over extended periods with Pactor before the newer soundcard modes were available, and I am told the new Winlink Express (new name for RMS Express) supports peer-to-peer on HF using sound card modes.

Asynchronous communications completely removes the need for simultaneous operating, but it isn't popular because it isn't "fun".  If the station is well configured with reliable equipment the operator is downgraded to a button-pusher.  Not much fun, but boy does it ever work efficiently.  Yes, it requires a computer, but if you have one why not use it?

Wally

7
Batteries & Solar / Re: Man Portable Off-Grid Power for Amateur Radio
« on: June 27, 2017, 05:20:49 PM »
I almost forgot the proof-of-concept. Here's my field station from last weekend

Is there a photo attached to this post?  If so, it hasn't been approved and we can't see it.

Wally

8
General Discussion / Re: Backpacks
« on: June 12, 2017, 01:11:01 AM »
(My emphasis.) There is a large empty space after this sentence and before the two concluding ones, but I see absolutely no link(s) nor pictures or any other kind of illustration in between.

I suspect Jon's photos are waiting for Admin approval before we can see them.

Wally

9
Antennas / Re: More info on the modified off center fed dipole
« on: April 28, 2017, 04:51:54 PM »
Very interesting, thank you!

Gil.

Gil, we can not see images in posts until you approve them.  Right now I can't see any images in this thread or Lamewolf's original thread.  Apparently that was a change you made when you implemented the paid subscription plan, images posted by non-subscribers have to be moderated (approved).

Wally

10
Antennas / Re: Super Gain 9db 40m NVIS Antenna.
« on: March 24, 2017, 06:33:40 PM »
Thanks Wally, very informative! What's the book?

It's "Electronic and Radio Engineering", 4th ed, by Frederick E. Terman from 1955.  It was a college textbook still in use back in the mid-1960s.  It was used in some of my courses, which is why I happen to have a copy.  Sigh, yes, I'm that old and obsolete...

I can see that in my minds eye, but the gain they are speaking of in this article is going straight up !  Good for NVIS, bad for DX !

That was pretty much the author's point - reduce interference arriving at a low angle from foreign shortwave broadcasters on 40m and favor high-angle NVIS regional contacts.  I don't believe the term NVIS was used back in the '60s when this article was written, but they certainly were aware of the effect.  As DJ6KR mentioned in his post, the significance of this article is the reflector laying on the ground underneath the antenna wire directing more of the energy upward.  Terman's book (Figure 23-36) shows "Directive Gain" of about 8 at  a spacing of 0+ to about 0.1 wavelength and then steadily dropping to about 4 at 0.3 wavelength, where the plot ends.

The same figure has "Radiation Resistance" plotted at the same spacing scale, and it gets better as spacing goes up.  The downward sloping Directive Gain plot crosses the upward sloping Radiation Resistance line at a spacing of about 0.17 wavelength.  This yields a Directive Gain of about 7 and Radiation Resistance about 50 ohms.  That is probably the sweet spot for overall efficiency, but it puts the antenna up about 22 feet, which is still NVIS territory, but is much less convenient than 7 feet.  Additionally, Terman's figure is based on a reflecting screen beneath the antenna; 3 wires 6 feet on center may be a good approximation of a (40m) screen at 7 feet height but I wonder if additional reflecting wires would be necessary with higher antenna elevations, just because of the geometry.  At 7 feet the "screen" is wider than the antenna height, so would a 22 foot high antenna require a much wider "screen"?  I suspect it would to get the maximum effect.

Wally

11
Antennas / Re: Super Gain 9db 40m NVIS Antenna.
« on: March 23, 2017, 09:11:28 PM »
It is all about the reflector on the ground under the Antenna, I think.

Yes, I have a copy of Terman's book that is referenced in the article.  Terman discusses a "Half-wave Antenna with Reflector" starting on page 903 and derives the gain.  He shows plots of gain compared to radiation resistance as a function of antenna to reflector spacing.  Radiation resistance (and efficiency) goes way down with small spacing, while gain stays around 8 up to a spacing of about 0.1 wavelength (about 13 feet on 40 m) before falling off with increased spacing.  He says:

"In order to prevent incidental loss resistances from making the antenna efficiency very low, the spacing S should accordingly be at least 0.05 wavelength, and preferably 0.1 wavelength."

The article uses 7 feet, which is about 0.05 wavelength at 40 meters, but Terman's chart shows you would have better efficiency without losing gain if you made the antenna 14 feet high.

Wally

12
New To Radio / Re: Problem with antenna on 1 of 2 radios
« on: March 21, 2017, 06:02:21 PM »
With the working regular antenna that came with it, if I put my finger on the antenna and gently push in one of several directions, the incoming signal shuts off, as if the antenna has been removed. 

I haven't pulled a Baofeng apart to verify this, but it sounds suspiciously like the antenna connector is soldered directly to the edge of the printed circuit board and the connection is broken.  Since flexing the working antenna loses signal it sounds like it normally makes contact but any movement breaks the connection.  The odd antenna may fit slightly different from the stock antennas and deflect the connector enough to cause the problem.  This was a problem with the old Icom W32A dual band handhelds; an impact to the antenna could break the circuit connection and cause intermittent operation.

If you are comfortable with a soldering iron you can attempt to take it apart and touch up the connection or circuit traces leading to the connector.  At the price of a Baofeng you don't have much to lose.  If you transmit with the connection broken you may fry the output anyway.

Wally

13
Net Activity / Re: Preppers Calling Frequency.
« on: February 23, 2017, 05:16:24 PM »
I'm not sure such a frequency legally exists.

Only on 160 and 60 meters as far as the US is concerned.  Attached is a screen shot of the HF portion of the table I linked above.  Note that 80 meters is defined as 3.525-3.600 MHz and 75 meters is defined as 3.800-4.000 MHz.  40 meters is divided into two segments, 7.025-7.125 MHz and 7.175-7.300 MHz.  You are right, digital modes are not permitted in the phone allocations.

I believe this was one of the reasons the ARRL requested a rule change where the FCC would regulate by bandwidth rather than by mode, but I don't know what happened to that proposal.  There was a lot of objection because some people said they were just trying to turn all the bands over to "robot" digital stations.


Wally

Edit to add:  Full Members can't post images without approval now?  It says my screenshot is waiting for approval.


14
Net Activity / Re: Preppers Calling Frequency.
« on: February 22, 2017, 06:49:08 PM »
No, it isn't an ARRL Band Plan, it is in the FCC Part 97 regulations,  "§97.305   Authorized emission types".  No 40 meter phone from the continental US below 7.125 KHz.  I took this straight from a government web site which has nothing to do with the ARRL:
http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=336ab7469b61ecbfa15086dbf1bf2c59&rgn=div5&view=text&node=47:5.0.1.1.6&idno=47#se47.5.97_1301

Edit to add:  this link takes you to Paragraph 97.301 which details the limits for each ITU region.  Scroll down to Paragraph 97.305 for details.  Although the entry "7.075-7.100 MHz    Phone, image" appears to authorize Phone, footnote 97.307(f)(11) takes it away for the continental US:

Quote
(11) Phone and image emissions may be transmitted only by stations located in ITU Regions 1 and 3, and by stations located within ITU Region 2 that are west of 130° West longitude or south of 20° North latitude.

Wally

15
General Discussion / Re: Survival Radios, Really?
« on: February 02, 2017, 04:50:22 PM »
These go-boxes are good for disaster relief supported by an infrastructure, not for preppers on the move.

Or, they are good for the "radio operator" supporting a group in a retreat setting, if you happen to be a member of a group with a retreat.  For an individual on the move... not so much.  It goes back to the first thing people should do but isn't much fun, so it tends to be avoided:  define your realistic needs before obtaining the equipment.  Over and over again we see people on other forums asking "what radio should I get?  Is the Baofeng a good choice?"  Not one word about what purpose they expect the radio to serve, not one word about their terrain, not one word about who they want to talk (or listen) to...  IMHO it is very much like asking "how long is a piece of string?"  But if you ask them for details there usually is no answer.

Wally

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