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Latest Topics

Topic Created Posts Views Last Activity
miniverters Jul 15th 2023, 17:50 1 1,935 on 15/7/23
I have lived in apartments and have had antenna restrictions for many years, never getting on low ba May 15th 2023, 16:30 1 1,818 on 15/5/23
A LOST ART Apr 23rd 2023, 19:42 1 2,011 on 23/4/23
"Faraday Telescope" Oct 21st 2019, 18:10 1 7,627 on 21/10/19
ham open club wi fi Oct 15th 2019, 12:21 4 6,913 on 11/4/20
Facebook Hams May 17th 2016, 18:51 1 6,449 on 17/5/16
HTX-202 back up battery Mar 22nd 2016, 20:49 4 10,156 on 30/3/16
ghz frequency loop yagis Feb 9th 2016, 00:53 6 6,678 on 19/2/16
Using wi-fi routers ("mesh system" 2012? qst) Oct 3rd 2015, 19:07 3 11,585 on 21/2/18
question about wi-fi routers Aug 15th 2015, 23:28 4 9,908 on 27/8/15

Latest Posts

Topic Author Posted On
miniverters wd6ejn on 15/7/23
Some years ago I bought an MFJ two meter ssb/cw transceiver.
I had a sched with the weak signal group which the net control was on the north side of the mexican border, probably a hundred miles away Encinitas/Portrero? I can't remember his call but one of the fun things I would do I check in once a month turning the power down to less then half a watt! the moderator would welcome me and I would enter his log.
I discovered this rig sells for over $400.00 on MFJ.
I can't get at it (along with other items) but it would be fun to place a small beam on the balcony.
I have been wanting to build a home made diy (kit) using a miniverter and 10 meter rig or perhaps my mfj two meter ssb/cw rig for more stability on 10 gigs or lower for more stability.
Most of the comercial transceivers are rather large and very experimental not to mention way above my budget.
Since one or two transverters (miniverters) are auxillary boards I would not have to buy the other bells and whistles that make them so expensive.
I have lived in apartments and have had antenna restrictions for many years, never getting on low ba wd6ejn on 15/5/23
I have a question on corner reflectors.
I have been trying to build a corner reflector for 70 cm but can no longer find an antenna calculator for this band (or any other),
aside from a desire to have accurate information for more quality
I happened to notice the similarity of the corner reflector to a radio telescope horn.
What I was wondering was is the shape of the horn ( other then circular polarization) for band width or more gain with respect to frequencies.
If I were to build my corner reflector using this arrow shape (on two sides vertical polarization) would I have more gain?
From what I can perceive from what little calculations and numbers for the dimensions are on the web, as the antenna becomes larger the scale of the antenna and the rods toward the front are much longer then the ones next to the
dipole much like the american flag as a two foot flag and a 6 foot flag are the same simetry by law, is this purely for bandwidth or more gain also? If the rods in front of the dipole are 12-13 inches and the ones out 3 or four feet to the front are much longer, would this work better?
A LOST ART wd6ejn on 23/4/23
Some time ago I attempted to build several high gain designs of yagi, quad, and loop quad antennas.
Having to live in tiny apartments with my mom never had much luck with the information on these sites (my antennas were still not stealthy) so I contiued with using the stealth droopy drawers on my balcony to get into the Palomar club two meter repeater and Catalina repeater.
I recently came upon the mindset of using a corner reflector using aluminum mini blinds as they are actually somewhat affordable.
We had to move once again as the covid scare put us in a more secure place I didn't need this bear belly after the sheltering in place!
When I built these other yagis and loop quads (one for wi-fi local network I was picking up a network from a great distance the motel 6 almost a half a mile away).
Now I have discovered corner reflectors and cannot find the same (not being able to use sites such as www.softcom,g3jvl,k6ksn,k7mem as a portable calculators)
maybe this computer is just too old and does not access the mathematical info that I need or is the internet just turning into a informational junk yard?
"Faraday Telescope" wd6ejn on 21/10/19
Almost two decades ago I started fashioning long loop yagis with information I got (see my other post re wi fi loop yagi) on the internet (loop quad or loop yagi calculator)as a unwilling abused neighbor I spent most of these years devising stealth antennas to hide outside.
Even a thirty gage wire can arouse suspicion in many busy bodies, and I'm not just talking about hoa's if you rent in one of these stalig 13s
you can have an all out battle as "you have no rights" to join in any activities as home owners do.
So I decided to avoid the "inconvenient bands" (hf) and build indoor antennas to beam out skylights or on a balcony no luxury of an attic in an apartment.
My latest experiment is a 20 foot long 70 centimeter loop yagi having just over 20 (approx 12" spacing or less) directors as I have exactly 20 feet from sliding door balcony to front door.
I decided to use a very small gage wire of 30 gage memory wire wich
is silver plated so that I can use an extremely high gain tunable (432-435 mhz) radio telescope (hopefully under 100$) preamp with cor relay less then 10 watts for weak signal work.
I'm really not interested in traditional dx contacts and hope to have a following of local hams interested in cw.
It looks as if the 30 gage driven element will be spaced extremely close to the 1st and second directors and reflector as the influence on them seems almost nonexistant, I don't know how this will effect gain.
As sites such as ssb electronics and Down East Microwave also Ramsey Electronics have disapeard, I am having hard time Google searching for a preamp to compensate for the db loss from the faraday cage of a tiny apartment, I'm talking about 100 db gain and < 1 noise figure.
I had no luck at all with the silver plated "memory wire" Itossed it in with the 1-800-junk stuff!
So, since the 20 + directors and reflector loop are 1/4" wide and 9-10" diameter, I decided to make the the driven element the same and copper to solder to I wonder how much difference it would make if the driven element was sterling (no I'm not going to swipe car exausts or antique stores) silver less then 1/4" wide .
It appears that when I was tuning the memory wire I must have forgot to solder the ends of the open end of the loop back, making the resonent frequency go away together, now I have 1.1-1 from 432 to 435 mhz, emulating the mfj swr anylizer for a high radio telescope preamp which I have not found yet, all I have is an old Radio sShack scanner which is useless and all I hear is a lot of noise (probably 40-50 noise level and nothig else let alone anything on 70 cm sub band.
I was forced to move some distance from here and was able to place less then half the loops (10 or so?) and tried to have 432-449 mhz.
the signals from repeaters are so strong this did not work so I am going to look up repeater input frequencies and 432 MHz weak signals.
When I had the 20 foot loop yagi inside the apartment I used the 100 uwatt? signal as a sort of beacon,, to my surprise I actually heard the signal from the mfj antenna anylizer about a quarter of a mile away actually threading through buildings and alleys!
I was up about 20 feet on the second floor.
The rules re motif pronounced motif! are more strict re indoors so I had to put the yagi on a balcony, I also use a stearling silver wire (22 ga) and it tunes great but still can't hear anything.
I'm thinking now of just making a corner reflector and using the stirling silver loop, the turning radius will be limited but it seems that a corner reflector should work a lot better.
I have searched endlessly for something a lot smaller (probably 8 feet on each side and 90 degree angle with no luck, everything is the same.....a lot of real estate or nothing.
So, now that the yagi boom has been reduced to 8 feet (I hide it under the edge of the upper balcony eave, (I am using the same 2" diameter pvc mast for my 95 year old mother's hdtv antenna, so when I want to try to hear a 70cm signal from a handie talkie on the input of a repeater, the hdtv signal usually goes away! I tell her its just the weather) I am going to see if I can find a roll of pure silver or gold for the loop elements as I figure I can always recycle what's left I have been using aluminum foil cut with a paper circle cutter and the aluminum does not seem to work with anything less then 20 feet as the indoor antenna, although there was that cool happening with the uwatt signal going almost 1-4 mile.

ham open club wi fi wd6ejn on 21/10/19
It's already about 5 feet long! I must have 20 loop elements on it, but the signal goes away when I use the inboard antenna.
No one else can get this network on a smart phone or laptop!
I seem to know what I am doing when it comes to antennas although not this.
I added 10 more 30 millimeter diameter (d 21-d 30) copper loops and made the spacing closer probably a mistake, now the signal is even harder to find, could be adding another wall and scaffolding increased the value of my faraday shield/cave.
What I really need now is a tp link repeater/extender with a 50 foot ethernet wire brown color to match the outside wall, I want on e with a n aux antenna jack so I can make one of my invisible beam.

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