Date   
Re: Availability of Mag Loop and other stuff...

Donald <donwestpwl@...>
 

Jack, ham radio is a hobby for me, too. Please keep up your experiments and post anything you care to share. As a renter, magnetic loops interest me, and *your* experiments will improve the probability of *my success*.

Donald, KB5PWL

On 6/1/2019 9:16 PM, Jack Purdum via Groups.Io wrote:
Good grief, guys, this is a hobby for me. Allison, are you really trying to be helpful here, or simply showing that you have a lot of RF experience? Perhaps the best solution is to do no testing and simply say we made contacts with it and leave it at that. Pretty hard to criticize the methodology when there's no information given. We have an EFHW available to us for testing, so that's what we're using. Also, there are a lot of hams out there using EFHW antennas so any testing we do with it will have meaning to them even if it does have a crappy radiation pattern for testing. If it's not ideal, so be it. My chances of renting two fiberglass crafts to sit on the Great Salt Lake loaded with a boat-load of equipment and antennas are about zero. Someone else with deeper pockets than I have will have to do that testing.

The good news is that if we do write an article on our ML experience, no one has to read it.

Jack, W8TEE



On Saturday, June 1, 2019, 4:17:30 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Jack,

the biggest issue is the 80-10 EFHW has a terrible pattern, broadside at 80m and by 20M
its a 4 lobe pattern with 10m its practically endfire.

That creates issues and questions for comparison as the EFHW is then rarely aimed at
the receiving station and hence you do not have a known comparison.

Generally when testing loops a loop of known performance are used but testing at HF is
never easy as the near field is at least 5 to 10 wavelengths or more and ground quality
dependent.  You want that distance to be able to see the total field.   The easiest rig
for that kind of testing is two fiberglass boats on calm salt water (an almost near
perfect ground plane).  Of course that does not include RF sources and calibrated
receivers and accurate GPS.

Allison

Re: HFSignals poor butiosiness practices

Ashhar Farhan
 

Guys,
He is talking about the BITX40, not uBITX. We seem to have forgotten the elder.

73, f

On Sun, Jun 2, 2019 at 6:10 AM Don - KM4UDX <dontAy155@...> wrote:

John -- I too was surprised by the quality of parts...the mini audio jacks, PPT switch and the encoder are examples of "value engineering" at its finest (worst!).  But what we have here, in its totality, is a very clever bit of kit -- and an astounding value for $130. 

While I could buy any modern professional commercial radio with lovely knobs, high quality enclosure, professional jacks (!), ample volume, AGC, S-meter, and a thousand other features, I just had no interest.   You have to want to build, solve, create, experiment, tinker  a bit, and communicate with others for help.  And provide a few of your own parts from the junk box when you break the el-cheapo kit parts, or if you just can't stand the way they feel or look. 

Example: A buddy of mine couldn't stomach the inexpensive feel and look of the rotary encoder (he may have "accidentally" stepped on it as well..hahah).  So he purchased a really nice version, in a lot of 5.  He gave me one.  It feels soooo good compared to the included kit encoder. And it just looks sturdy and well made, as it is. So I have tossing out the cheap included encoder and replacing it with the sexy sturdy version, on my "round-to-it" list.  But I will never get "round-to-it". Why? The included cheap encoder works fine, and I never really turn the knob anyway.  Rig control and digital modes from my laptop take care of all the frequency changes.  And I put in a Nextion screen (dreamy!!), so I use the touch interface to do most of the freq changes.  But the encoder works anytime I need it.  The poor cheap encoder, made from tinfoil, will last a thousand years as is. 

Ditto with the little PPT surface mount switch.  When I figured out what it was, I thought it was the most ridiculous thing I had ever seen.  But then I built the mic in a pill bottle, and the stupid cheap surface mount PPT switch fit just fine on the side of the pill bottle mic.  It too will last for a thousand years. 

This kit radio can not be brought into the world without a fair amount of "you" added to it. If you like this process, you will love this 80-10 band 20-2 watt transceiver. 

And asking for help in this community is also an extraordinary experience.  After I built my radio, it would receive great, but no TX.  I was sooo frustrated.  A fellow in this IO community said,  "look, put it in a box, send it to me, and let me look at it.  If it takes any new parts, you pay for them, but I'll do the labor, no problem".  So I put my kit radio  in a box and mailed it off to a complete stranger a long way away.  

Turns out, as is often the case with me, I had screwed up a drive pot.  My angel of mercy just twisted it to the right setting, put it in the box, and set it back to me.   You could make the argument that as good as a value as the kit is, the value of the community of builders here is 100 times more valuable.  

If you want to see my uBITX in its current glory, and the goofy pill bottle mic, see my www.qrz.com page. I found it very very helpful to keep looking at the work of others to encourage me. If you want to see  some uBITX performance, wait a week and see my results on WSPRnet under KM4UDX  This little radio, and a multi-band compromise antenna, gets to the farthest reaches of the planet. Pretty good value for you money.

(*) I'm in the middle of a computer change over.  But when using the old computer last month, my uBITX was in the top 20 world wide for 2 way WSPRnet spots. This is competing with wicked professional gear, with their great quality components(!)  And this little uBIX kit, with the cheapest jacks and encoder in the world, is running ahead of almost all of them. 

If I can help, just ask.

Don
km4udx

Re: Availability of Mag Loop and other stuff...

Alan de G1FXB
 

Hi Jack,
It's a hobby to me as well, Constrained by finite time and money.
There are many miracle claims, just using cheap & simple gets overlooked.
Your reference the realworld ingenuity of to your friends use of the dipole was what I was trying to portray,


Not to dissuade you,
The suggestions just were a way to get best results, fewest doubts in half the time?
Wish you luck and I look forward to seeing the write-up, and it warrants building over a traditional STL.



regards Alan

On 02/06/2019 03:02, Jack Purdum via Groups.Io wrote:
If I were writing a treatise on mag loop antennas, I might worry about simultaneous transmissions and similar exogenous factors, but we're not. Chances are, we will do some simple tests using CW, SSB, and probably FT8 or FT4. We will transmit for a period of time, switch antennas and see what happens. We will be collecting data from WSPR and the beacons, but it is all constrained by the time we have to do such things. Our goal is not to probe the physics of the ML, but rather to provide enough information to those who are interested to decide if it's worth the effort to build a ML. One of our club members is using a dipole on 40M and uses thumb tacks to hold it to the ceiling, bending around 90?? corners, yet he's still making contacts. All he wants to know is if he can put one out on his balcony any make contacts with it on 20M.

The good news is that I believe that the construction article we plan should be sufficiently robust that you can build one, too. Then the ball's in your court and you can do the depth of testing you mention. I simply don't have enough grains of sand left in the hourglass to worry about it that much.

Jack, W8TEE

On Saturday, June 1, 2019, 4:45:46 PM EDT, Alan de G1FXB via Groups.Io <g1fxb@...> wrote:


Thanks Jack,

Long answers are good and indicate your willingness for full disclosure.

(Manufactures antenna specifications tend to be BS generators?
Second only to the HiFi industry.??
Remember the kids in the mid 1980's with their "Ghetto Blasters" advertised with 780 Watts of stereo music power, and all from 8X D cell batteries.
In fairness some of the manufactures provided revised figures when used on mains power, nearly a KW.
Man those things must have being efficient, and all through a skinny power cord....)

I couldn't find on the pacciffic66 site what they reference their figures to, on that initial page at least?
hopefully it's something real and not against some theoretical property.
One of which, the proper name escapes me at this time.
(my numbers for instance :-)
6ft of wire whether straight or coiled is a larger percentage nearer a useful wavelength ie: 1/4wave?? at say 28MHz (approx 8ft) than the same 6ft of wire to 14MHz
I interpret this to It's a simple expression of comparison of physical length to wavelength, nothing to do with the antenna efficiency and devoid of losses in the matching networks that are necessary, etc, etc.
Even if it's a real antenna they are referencing it to, it in it's self could be a compromised reference gives great headline numbers.
Check the fine print!

Suggestion:- At least do the theoretical model of what ever you choose to use as the loop reference antenna against a full size centre fed dipole at identical heights, even if not a real world test.
Granted it's monoband & optimally performs mounted half wavelength above the ground but it's a good indicator & reference, and as cheap & simple?? to construct as it gets.
if you don't like what you see in the comparison it's between you and your conscience.
You can cripple it's performance and justifiably conclude an XYZ antenna, is greatly more efficient than?? a halfwave dipole when mounted at 15ft agl for example.... :-)

Saw the reports of doing A/B comparisons, however quick the changeover there is always the element of doubt as to propagation.
the ideal is simultaneous TX to both antennas in the same lot but far enough not to interact is the goal.
In the real world two antennas one each in the same town is good enough. What's a mile over a propagation distance of say 6,000??
everyone has their preferred mode, be it CW, WSPR the latest digimode.???? Reality it doesn't matter?
The requirement is for as many & widespread coverage of receiving stations as possible??
That said, QRP-Labs kits are cheap enough to utilise two, and compare like for like WSPR time slots to each of your and AL's callsigns allocated to each different antenna?


regards Alan

On 01/06/2019 17:27, Jack Purdum via Groups.Io wrote:
Alan:

The results right now are modeled using the usual Pacific66 app. However, we do plan "real" tests in an attempt to get some useful data. Our reference antenna will likely be an 80-10M EFHW which we both use. Al also has a vertical that we might test against. However, the EFHW is always available; not so with the vertical.

We read in a paper that someone added a ground plane and said it "made a difference", whatever the hell that means. Anyway, because of that, we want to try it and see if it does have an impact. We have already noticed that the shape of the feed loop makes a difference, as does its position in the vertical plane. The effect is small, but real.

Al and I have talked about this a lot, and our feeling is to publish the results of the "Double-Double" as a construction article. (I want to call it the "Luggable Double-Double" but Al's not happy with that.) There are controllers out there (Loftur Jonasson) so my feeling is that will be kept for the book only. Also, it will be somewhat unique in that we hope to add a TFT display that shows the SWR in realtime as a plot. We have arranged to have all of the projects' PCB's available at a reasonable price.

Al and I are writing the book in a strange way. We are going to finish it before signing with a publisher. The reason is because I know the time pressures that editors put on authors with respect to deadlines and we want to get this right rather than to market fast. Our TOC has 18 chapters, of which the first 4 are really setting up the software for the Arduino, Teensy, STM32, and ESP32 ??C's and giving the beginning reader enough C instruction to read our code (and shoot themselves in the foot a few times?) We see 12 projects in the book, some of which (e.g., the ML) are two chapters--construction and software. Some are "end products" (e.g., the ML, a different antenna tuner, CW messenger, CW decoder, CW Tutor) while others are test equipment (e.g., programmable power supply, AC voltmeter, signal generator). The last chapter is on using what you've built to troubleshoot a receiver. We think it will be a very unusual, but useful, book. Our goal is to have it done by the fall. We currently have 9 chapters done.

Long answer to a short question...


Jack, W8TEE


On Saturday, June 1, 2019, 12:01:46 PM EDT, Alan de G1FXB via Groups.Io <g1fxb@...> wrote:


Hi Jack,

Sounds like you are on to something special with 90% and even the 40% are impressive figures.
(Noted that they are modelled?? efficiencies at this point in time, here's hoping with can you can achieve something approaching in practical tests.)
To what reference antenna (also at the same modelled height to compare like for like) ?

Interested in your comment the trials of a counterpoise,
Previous papers indicate loop type antennas were considered a free space antenna requiring no ground plane / radials
I guess it's the feed / matching & counterpoise is where the magic happens?

As it's using an auto tuner is the write-up destined for your new book is there an ETA, or another perhaps magazine article release?

(One gotcha about some of the previous, (not your) small "miracle" antenna's.
Check it's actual the antenna doing the radiating and not the feed line, or counterpoise even the mounting pole has being known to be "accidentality" hot with RF.
(However disguised, generally any antenna employing a braid breaker / balun in the coax away from what they make you believe is the feed point or suggested feeder or support lengths perhaps warrants a second look.))


regards Alan

On 31/05/2019 18:45, Jack Purdum via Groups.Io wrote:
We are also trying to assess other factors, too, such as a counterpoise and its affect on performance. We may find that these "other factors" play no significant role in the antenna's performance. Still, learning that something doesn't matter is as helpful as learning what does matter.

Jack, W8TEE

Re: HFSignals poor business practices

KB2HSH
 

Wow. 

You must seriously lack many skills needed for life, not just in building a radio. To blame OTHERS for your inability is hilarious.  Glad I don't live by OR associate with you. 

Re: HFSignals poor business practices

ke6bgn@...
 

They also state on their webpage, the email address of the only place you can get support. My bitx40 board arrived with 1 of the toroids ripped from the board. I emailed them about it at the provided email address, and to this day, months later, bupkis........nada, zip, nothing, no reply. That type of support from the vendor excites me in the wrong direction, so much so, that I refuse to recommend their services to anyone. It also really drained my enthusiasm for the project I was going to build.
I understand that the vast majority of folks have a good experience dealing with this vendor, but it does seem to me that if something goes wrong with your initial purchase, the experience is not handled well by that same vendor most of time.
As always, your mileage may vary, but my gas tank is on fumes now from their underwhelming support.

73 de RC.....KE6BGN 

Re: HFSignals poor business practices

Christopher Miller
 

You could always just wind the inductor yourself for much less than it would cost to ship one around the world. The manufacturer isn't responsible for damage during transport, so you could go after DHL. (Im guessing )

Chris KF4FTR

Re: Availability of Mag Loop and other stuff...

ajparent1/KB1GMX
 

Jack,

Not showing off, no one is paying for it.  However when someone claims a loop
that 1-2db below a EFHW (or a dipole) that's pretty close to saying my 10 year
old Tacoma can win at Indy.  In short, not likely or the Indy cars had an unusual
handicap, like no fuel and must be pushed by pit crew.   Reality is that the EFHW
is pointed in some random direction relative to the station and the loop is aimed
though its 3db beam width is likely far wider than the EFHW or a standard dipole
at reasonable height.  That makes its aim very wide where a 80-10 EFHW on
40M will at best have a pattern with a beam width that is narrow as its 1
wavelength long.   I can claim and prove my square loop on 6M at 7ft is better
than my portable 6M full wave length rectaangle loop at 25ft  by pointing the
edge of the loop to the station at distance as the front to side is easily 20db
down.  For that I'm at least the same horizontal polarization.  The square loop
under that condition is about 14db better however if the big loop is aligned its
4 db worse.  In short that proves the big loop does really work and also proves
the omnidiriectional square loop is superior when omnidirectional coverage
is required.

In short comparing it to any antenna without some form of controls and claiming
performance is at best meaningless.    A valid compare is a full size vertical with
elevated radials as it will have known gain and similar takeoff angles.

Loops are cool antennas but they are small antennas and they nominally will be
negative gain compared to any dipole.  Its the nature of antenna compromise.

Fyi: the testing part is to show how difficult it is to get meaningful real world
test data with any accuracy at HF because of distances and even local
surface propagation.   Modeled is of value but care must be taken to use a 
model that works with small loops and real grounds (NEC4.2 engine).

As to helpful.  Yes I want people to realize the limits of small antennas and
the claims sometimes made that are against all modeled data and practical
theory never minding prior works done to verify the models.  To that I see a
lot of suppliers and articles for loops making claims like this is the new
better sliced bread.  

I use loops and I do apply them as they have characteristics that make
them useful.  First being they are self contained antennas. The other
feature is the nulls and their insensitivity to close in electrostatic fields.
Its what they are good at even when they are full sized 1lambda loops.

Allison

Re: HFSignals poor butiosiness practices

Gordon Gibby <ggibby@...>
 

In the last few days, I’ve learned how to do FT8 and probably JS8call as well.  I’ve been so busy teaching emergency communications that I haven’t been able to fiddle with my radios much, but that looks like a perfect thing to try with this cute little rig. 

Gordon 


On Jun 1, 2019, at 20:40, Don - KM4UDX <dontAy155@...> wrote:

John -- I too was surprised by the quality of parts...the mini audio jacks, PPT switch and the encoder are examples of "value engineering" at its finest (worst!).  But what we have here, in its totality, is a very clever bit of kit -- and an astounding value for $130. 

While I could buy any modern professional commercial radio with lovely knobs, high quality enclosure, professional jacks (!), ample volume, AGC, S-meter, and a thousand other features, I just had no interest.   You have to want to build, solve, create, experiment, tinker  a bit, and communicate with others for help.  And provide a few of your own parts from the junk box when you break the el-cheapo kit parts, or if you just can't stand the way they feel or look. 

Example: A buddy of mine couldn't stomach the inexpensive feel and look of the rotary encoder (he may have "accidentally" stepped on it as well..hahah).  So he purchased a really nice version, in a lot of 5.  He gave me one.  It feels soooo good compared to the included kit encoder. And it just looks sturdy and well made, as it is. So I have tossing out the cheap included encoder and replacing it with the sexy sturdy version, on my "round-to-it" list.  But I will never get "round-to-it". Why? The included cheap encoder works fine, and I never really turn the knob anyway.  Rig control and digital modes from my laptop take care of all the frequency changes.  And I put in a Nextion screen (dreamy!!), so I use the touch interface to do most of the freq changes.  But the encoder works anytime I need it.  The poor cheap encoder, made from tinfoil, will last a thousand years as is. 

Ditto with the little PPT surface mount switch.  When I figured out what it was, I thought it was the most ridiculous thing I had ever seen.  But then I built the mic in a pill bottle, and the stupid cheap surface mount PPT switch fit just fine on the side of the pill bottle mic.  It too will last for a thousand years. 

This kit radio can not be brought into the world without a fair amount of "you" added to it. If you like this process, you will love this 80-10 band 20-2 watt transceiver. 

And asking for help in this community is also an extraordinary experience.  After I built my radio, it would receive great, but no TX.  I was sooo frustrated.  A fellow in this IO community said,  "look, put it in a box, send it to me, and let me look at it.  If it takes any new parts, you pay for them, but I'll do the labor, no problem".  So I put my kit radio  in a box and mailed it off to a complete stranger a long way away.  

Turns out, as is often the case with me, I had screwed up a drive pot.  My angel of mercy just twisted it to the right setting, put it in the box, and set it back to me.   You could make the argument that as good as a value as the kit is, the value of the community of builders here is 100 times more valuable.  

If you want to see my uBITX in its current glory, and the goofy pill bottle mic, see my www.qrz.com page. I found it very very helpful to keep looking at the work of others to encourage me. If you want to see  some uBITX performance, wait a week and see my results on WSPRnet under KM4UDX  This little radio, and a multi-band compromise antenna, gets to the farthest reaches of the planet. Pretty good value for you money.

(*) I'm in the middle of a computer change over.  But when using the old computer last month, my uBITX was in the top 20 world wide for 2 way WSPRnet spots. This is competing with wicked professional gear, with their great quality components(!)  And this little uBIX kit, with the cheapest jacks and encoder in the world, is running ahead of almost all of them. 

If I can help, just ask.

Don
km4udx

Re: HFSignals poor business practices

Ian Reeve
 

The inductors on the pcb are fragile and the vendors take a lot of effort to pack well for its trip to the purchaser.Likely to receive not so gentle handling in the post or courier so unfortunately there will be some that arrive damage.That is my experience over the years, I have had items trashed despite more than adequate packing. The courier is responsible and for that reason I always sign unexamined. or make them wait whilst I open the parcel.Today's automated post and courier systems are very unkind to parcels as are sadly some postal and courier employees


From: BITX20@groups.io <BITX20@groups.io> on behalf of Christopher Miller <djmalak2k6@...>
Sent: Sunday, June 2, 2019 4:22:29 PM
To: BITX20@groups.io
Subject: Re: [BITX20] HFSignals poor business practices
 
You could always just wind the inductor yourself for much less than it would cost to ship one around the world. The manufacturer isn't responsible for damage during transport, so you could go after DHL. (Im guessing )

Chris KF4FTR

Re: HFSignals poor business practices

Ashhar Farhan
 

Our support is via hfsignals@.... the same as our paypal id.
- f

On Sun 2 Jun, 2019, 8:12 PM , <ke6bgn@...> wrote:
They also state on their webpage, the email address of the only place you can get support. My bitx40 board arrived with 1 of the toroids ripped from the board. I emailed them about it at the provided email address, and to this day, months later, bupkis........nada, zip, nothing, no reply. That type of support from the vendor excites me in the wrong direction, so much so, that I refuse to recommend their services to anyone. It also really drained my enthusiasm for the project I was going to build.
I understand that the vast majority of folks have a good experience dealing with this vendor, but it does seem to me that if something goes wrong with your initial purchase, the experience is not handled well by that same vendor most of time.
As always, your mileage may vary, but my gas tank is on fumes now from their underwhelming support.

73 de RC.....KE6BGN 

Re: Availability of Mag Loop and other stuff...

ajparent1/KB1GMX
 

Arv,

The problem of online RX or for that fact QRSS and WSPR sites is antenna alignment.
If you antenna is not "aimed" that way the result is it could have been a long path or worse
"off the side".  They do help with "have you been heard" and allows estimating propagation 
in a given direction but comparing A and B antennas requires care for both aim and
time of comparison as propagation is a transient thing.

MY 0.02$ on hobby, it is!  However taking peoples money with inaccurate or
extravagant claims should not be a hobby, though it is often a vocation people
pursue.  When people want to enjoy the hobby and are limited in time and budget
accuracy and good explanation is helpful.  When one expends time and money
on a course of action or material its desirable to understand what the outcome
may be or the limitations.

So every time a new antenna fad hits we have this.  Loops are indeed useful.
They are compact, self contained, and in some cases can help with local noise.
The yabut is they are very narrow band if they are as efficient as possible and
that leads to remote tuning as they are touchy and requiring SWR monitoring.
Being small antennas they are still low gain and therefor not the ultimate radiator. 
However the idea that I can get a loop and conquer the world from my garden
is loaded for disappointment as even the cheapest loop cost hundreds of
dollars and they most expensive ones are not that much better.  I've looked at
commercial loops and they are in the range of 199$ to well over 500$  that is
a lot of money to get an antenna that may be only passable or worse that it
can't work indoors in a building with metallic handicaps (stucco with wire, metal
framing, aluminum siding,  and foil backed insulation).  You have to keep it a
reasonable distance away from the radio so RF problems do not result.

As to building ones own, a good design wants a vacuum variable and they
are NOT cheap.  Air variables of the dual rotor forma can work ok but still
if you have to buy one they are costly.  Also the cap used determines max
power and tuning range as it had to withstand very high voltages even
at QRP levels.

That said if your junk box can full the need its interesting to experiment with Loops.


Allison

Re: Availability of Mag Loop and other stuff...

Jack, W8TEE
 

Allison:

I'm really only reporting the data that we had from the RBN reports. Your position seems to be that, because we didn't control all exogenous factors, the reports are meaningless...that no report is better than what we did report. I don't want to "claim" anything...that makes it sound like I'm selling something, which I'm not. I don't think anyone expects a shorten antenna to perform exactly like its full wave counterpart.

The best I can afford to do is report what I find with what I have. To me, something is better than nothing.

Jack, W8TEE

On Sunday, June 2, 2019, 11:39:10 AM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Jack,

Not showing off, no one is paying for it.  However when someone claims a loop
that 1-2db below a EFHW (or a dipole) that's pretty close to saying my 10 year
old Tacoma can win at Indy.  In short, not likely or the Indy cars had an unusual
handicap, like no fuel and must be pushed by pit crew.   Reality is that the EFHW
is pointed in some random direction relative to the station and the loop is aimed
though its 3db beam width is likely far wider than the EFHW or a standard dipole
at reasonable height.  That makes its aim very wide where a 80-10 EFHW on
40M will at best have a pattern with a beam width that is narrow as its 1
wavelength long.   I can claim and prove my square loop on 6M at 7ft is better
than my portable 6M full wave length rectaangle loop at 25ft  by pointing the
edge of the loop to the station at distance as the front to side is easily 20db
down.  For that I'm at least the same horizontal polarization.  The square loop
under that condition is about 14db better however if the big loop is aligned its
4 db worse.  In short that proves the big loop does really work and also proves
the omnidiriectional square loop is superior when omnidirectional coverage
is required.

In short comparing it to any antenna without some form of controls and claiming
performance is at best meaningless.    A valid compare is a full size vertical with
elevated radials as it will have known gain and similar takeoff angles.

Loops are cool antennas but they are small antennas and they nominally will be
negative gain compared to any dipole.  Its the nature of antenna compromise.

Fyi: the testing part is to show how difficult it is to get meaningful real world
test data with any accuracy at HF because of distances and even local
surface propagation.   Modeled is of value but care must be taken to use a 
model that works with small loops and real grounds (NEC4.2 engine).

As to helpful.  Yes I want people to realize the limits of small antennas and
the claims sometimes made that are against all modeled data and practical
theory never minding prior works done to verify the models.  To that I see a
lot of suppliers and articles for loops making claims like this is the new
better sliced bread.  

I use loops and I do apply them as they have characteristics that make
them useful.  First being they are self contained antennas. The other
feature is the nulls and their insensitivity to close in electrostatic fields.
Its what they are good at even when they are full sized 1lambda loops.

Allison

Re: Availability of Mag Loop and other stuff...

Jack, W8TEE
 

"However taking peoples money with inaccurate or extravagant claims should not be a hobby, though it is often a vocation people pursue."

Taking people's money? I'm not selling anything. My real goal is to get people constrained by HOA's or spouses back on the air.

Jack, W8TEE


On Sunday, June 2, 2019, 12:10:18 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Arv,

The problem of online RX or for that fact QRSS and WSPR sites is antenna alignment.
If you antenna is not "aimed" that way the result is it could have been a long path or worse
"off the side".  They do help with "have you been heard" and allows estimating propagation 
in a given direction but comparing A and B antennas requires care for both aim and
time of comparison as propagation is a transient thing.

MY 0.02$ on hobby, it is!  However taking peoples money with inaccurate or
extravagant claims should not be a hobby, though it is often a vocation people
pursue.  When people want to enjoy the hobby and are limited in time and budget
accuracy and good explanation is helpful.  When one expends time and money
on a course of action or material its desirable to understand what the outcome
may be or the limitations.

So every time a new antenna fad hits we have this.  Loops are indeed useful.
They are compact, self contained, and in some cases can help with local noise.
The yabut is they are very narrow band if they are as efficient as possible and
that leads to remote tuning as they are touchy and requiring SWR monitoring.
Being small antennas they are still low gain and therefor not the ultimate radiator. 
However the idea that I can get a loop and conquer the world from my garden
is loaded for disappointment as even the cheapest loop cost hundreds of
dollars and they most expensive ones are not that much better.  I've looked at
commercial loops and they are in the range of 199$ to well over 500$  that is
a lot of money to get an antenna that may be only passable or worse that it
can't work indoors in a building with metallic handicaps (stucco with wire, metal
framing, aluminum siding,  and foil backed insulation).  You have to keep it a
reasonable distance away from the radio so RF problems do not result.

As to building ones own, a good design wants a vacuum variable and they
are NOT cheap.  Air variables of the dual rotor forma can work ok but still
if you have to buy one they are costly.  Also the cap used determines max
power and tuning range as it had to withstand very high voltages even
at QRP levels.

That said if your junk box can full the need its interesting to experiment with Loops.


Allison

Sunil cases

Sam Tedesco
 

Hi everyone,

So...I have 2 builds in Sunil cases. One has an audio amp. The other does not.

On both cases... when I plug in external speaker/headphones, the internal speaker stays on.

Normal?

Thanks!

Re: HFSignals poor business practices

Arv Evans
 

Bob  KE6BGN

Could you provide us with the email address that you sent your complaint to?  That might help
with determining what went wrong.  How many times did you request help from that email site?

Was the inductor damaged in shipping, or does it look like it was a manufacturing flaw  (each
unit is tested for basic functionality before being shipped). 

Have you considered re-winding the core and soldering it back in place as a replacement for
the damaged one?

I took a look at the HFSignals web site and specifically the BITX40 pages:

Getting Help

If you are interested or building any of the HF Signals’ kits, you can join the BITX20 group by visiting https://groups.io/g/bitx20. That’s the only support we provide.  The level of collective wisdom and experience on the Forum is enough to sort out almost any technical problem or question you may have. You will also meet some really great builders on the Forum.

If you need information specific to your shipping, billing and other commercial matters, you can drop us a mail to hfsignals’ inbox at gmail. The mailbox is in the name of hfsignals followed by the regular gmail.com.

That site clearly says that the discussion group is the place to go for support, not the HFSignals
sales site.  You are now at that site so support should be available from many of us here on this group. 

SUPPORT:
If your toroid core is not broken it would be possible to re-wind it and solder that in place as a replacement.
If HFSigs were to send you a new inductor you would still have to solder it in place, so re-winding the damaged
one and soldering it in place would be a similar effort.  Wire size is not critical for toroid inductors, as long as
it can handle the necessary current and as long as the correct number of turns through the center hole can be
accommodated. 
Others will also probably have support suggestions that you may want to follow.  It might help if they knew
specifically which inductor was damaged.   This can be noted by component number or by its position on
the PCB.  A picture sometimes helps to make things clearer.

Arv  K7HKL
_._





On Sun, Jun 2, 2019 at 8:42 AM <ke6bgn@...> wrote:
They also state on their webpage, the email address of the only place you can get support. My bitx40 board arrived with 1 of the toroids ripped from the board. I emailed them about it at the provided email address, and to this day, months later, bupkis........nada, zip, nothing, no reply. That type of support from the vendor excites me in the wrong direction, so much so, that I refuse to recommend their services to anyone. It also really drained my enthusiasm for the project I was going to build.
I understand that the vast majority of folks have a good experience dealing with this vendor, but it does seem to me that if something goes wrong with your initial purchase, the experience is not handled well by that same vendor most of time.
As always, your mileage may vary, but my gas tank is on fumes now from their underwhelming support.

73 de RC.....KE6BGN 

Re: Availability of Mag Loop and other stuff...

Ian Reeve
 

Spent some time with a low budget may loop made from straight pieces of thick aluminium strip bolted in a hexagon shape with a remote tune function fed by a separate coax cable from a 12v supply.Deliberately designed to add a little resistance to the "loop" to reduce the spacing on the variable tuning capacitor,it worked.Hanging it from a tree branch it proved to receive signals two s points below my half size windom.Transmit showed a similar pattern.No efficiency figures for either antenna,just receive and transmit reports.The transceiver used a k3 at 100 watts at the input to the power/swr meter.There are some very fancy loops around at equally fancy prices but it seems to me a loop of copper pipe( 6 or 8mm diameter central heating radiator supply) of 1 meter overall diameter would be a good starting point.I understand that the lest resistance in the loop is paramount and therefore a massive voltage will be across the tuning capacitor which ideally needs to be of the vacuum sort.Either way the loop is resonant over a very narrow band and a being directional,useful to reduce troublesome qrm.As to efficiency,I will leave the calculations to the folks who know.


From: BITX20@groups.io <BITX20@groups.io> on behalf of Jack Purdum via Groups.Io <jjpurdum@...>
Sent: Sunday, June 2, 2019 5:35:38 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Availability of Mag Loop and other stuff...
 
"However taking peoples money with inaccurate or extravagant claims should not be a hobby, though it is often a vocation people pursue."

Taking people's money? I'm not selling anything. My real goal is to get people constrained by HOA's or spouses back on the air.

Jack, W8TEE


On Sunday, June 2, 2019, 12:10:18 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Arv,

The problem of online RX or for that fact QRSS and WSPR sites is antenna alignment.
If you antenna is not "aimed" that way the result is it could have been a long path or worse
"off the side".  They do help with "have you been heard" and allows estimating propagation 
in a given direction but comparing A and B antennas requires care for both aim and
time of comparison as propagation is a transient thing.

MY 0.02$ on hobby, it is!  However taking peoples money with inaccurate or
extravagant claims should not be a hobby, though it is often a vocation people
pursue.  When people want to enjoy the hobby and are limited in time and budget
accuracy and good explanation is helpful.  When one expends time and money
on a course of action or material its desirable to understand what the outcome
may be or the limitations.

So every time a new antenna fad hits we have this.  Loops are indeed useful.
They are compact, self contained, and in some cases can help with local noise.
The yabut is they are very narrow band if they are as efficient as possible and
that leads to remote tuning as they are touchy and requiring SWR monitoring.
Being small antennas they are still low gain and therefor not the ultimate radiator. 
However the idea that I can get a loop and conquer the world from my garden
is loaded for disappointment as even the cheapest loop cost hundreds of
dollars and they most expensive ones are not that much better.  I've looked at
commercial loops and they are in the range of 199$ to well over 500$  that is
a lot of money to get an antenna that may be only passable or worse that it
can't work indoors in a building with metallic handicaps (stucco with wire, metal
framing, aluminum siding,  and foil backed insulation).  You have to keep it a
reasonable distance away from the radio so RF problems do not result.

As to building ones own, a good design wants a vacuum variable and they
are NOT cheap.  Air variables of the dual rotor forma can work ok but still
if you have to buy one they are costly.  Also the cap used determines max
power and tuning range as it had to withstand very high voltages even
at QRP levels.

That said if your junk box can full the need its interesting to experiment with Loops.


Allison

Re: Availability of Mag Loop and other stuff...

Arv Evans
 

Antenna measurements are for the most part relative to some measured reference signal between
the antenna being tested and the remote reception point.  Antenna at the remote reception point
would seem to be immaterial as long as it does not change characteristics during the tests.  In most
antenna test ranges it is the device being tested that is rotated with the received signal at a fixed
point being measured.  This allows measurement and documentation of signal levels at various
angles of radiation.  Rotating or moving the receiving site is not necessary and would probably
invalidate the measurements. 

Small loop antennas are interesting for another reason.  They can be mounted and measured in
either horizontal or vertical position relative to the local ground plane, or at any angle in between. 
This gives one an idea of which propagation angle might be more advantageous, but only an
idea of that.  Propagation at later dates may totally invalidate any reference measurements that
have been made and published. 

My 2 pence worth. 

Arv
_._


On Sun, Jun 2, 2019 at 9:39 AM ajparent1/KB1GMX <kb1gmx@...> wrote:
Jack,

Not showing off, no one is paying for it.  However when someone claims a loop
that 1-2db below a EFHW (or a dipole) that's pretty close to saying my 10 year
old Tacoma can win at Indy.  In short, not likely or the Indy cars had an unusual
handicap, like no fuel and must be pushed by pit crew.   Reality is that the EFHW
is pointed in some random direction relative to the station and the loop is aimed
though its 3db beam width is likely far wider than the EFHW or a standard dipole
at reasonable height.  That makes its aim very wide where a 80-10 EFHW on
40M will at best have a pattern with a beam width that is narrow as its 1
wavelength long.   I can claim and prove my square loop on 6M at 7ft is better
than my portable 6M full wave length rectaangle loop at 25ft  by pointing the
edge of the loop to the station at distance as the front to side is easily 20db
down.  For that I'm at least the same horizontal polarization.  The square loop
under that condition is about 14db better however if the big loop is aligned its
4 db worse.  In short that proves the big loop does really work and also proves
the omnidiriectional square loop is superior when omnidirectional coverage
is required.

In short comparing it to any antenna without some form of controls and claiming
performance is at best meaningless.    A valid compare is a full size vertical with
elevated radials as it will have known gain and similar takeoff angles.

Loops are cool antennas but they are small antennas and they nominally will be
negative gain compared to any dipole.  Its the nature of antenna compromise.

Fyi: the testing part is to show how difficult it is to get meaningful real world
test data with any accuracy at HF because of distances and even local
surface propagation.   Modeled is of value but care must be taken to use a 
model that works with small loops and real grounds (NEC4.2 engine).

As to helpful.  Yes I want people to realize the limits of small antennas and
the claims sometimes made that are against all modeled data and practical
theory never minding prior works done to verify the models.  To that I see a
lot of suppliers and articles for loops making claims like this is the new
better sliced bread.  

I use loops and I do apply them as they have characteristics that make
them useful.  First being they are self contained antennas. The other
feature is the nulls and their insensitivity to close in electrostatic fields.
Its what they are good at even when they are full sized 1lambda loops.

Allison

Re: Sunil cases

Ian Reeve
 

I would say that's not right,normal convention would be to cut off the internal speaker.I my ubitx I have not used the little pcb,there may be a issue with the wiring or the pcb design.I do know that with the version I had,the headphones when plugged in only worked on one ear.A link is needed on the board to get audio on both ears.I have wired the three sockets directly to the appropriate wires.


From: BITX20@groups.io <BITX20@groups.io> on behalf of Sam Tedesco <stedesco619@...>
Sent: Sunday, June 2, 2019 5:58:01 PM
To: BITX20@groups.io
Subject: [BITX20] Sunil cases
 
Hi everyone,

So...I have 2 builds in Sunil cases. One has an audio amp. The other does not.

On both cases... when I plug in external speaker/headphones, the internal speaker stays on.

Normal?

Thanks!

Re: HFSignals poor business practices

Vaughn
 

I and a colleague, got one of these HFSignals kits, as sourcing the parts, getting them cheap enough and then doing all the building, was just out of our time span. Having the main board built and tested, for the very reasonable cost, was by far the better idea.

On receiving the parts, I too, was disappointed in the 4mm diameter shaft pots and the very small ptt switch. I decided, there and then, to purchase better, more normal, 6mm shaft pots and adapt an old mic with built in ptt, I had form an old PC. Since then I have added and adapted, other parts to make this a better radio more able to do what I want it too. As for building and modifying, all required info was on the HFSignals website, you just had to look. This group also gave a lot of help, if you asked, so very easy and fun to build.

All in all I am very pleased with the result and cost. I could not get a radio like this, for this cost and to have built and modified this I have the fun of building and the glee of when it works. For a few hundred pounds I can buy a better kit, but for that price I cna also buy secondhand radios.

I think HFSignals have done great. I may make the uBIX version, also from HFSignals, as this has more than one band on it from the start, so I think may be easier to build, as a duel ban radio. I also like the idea of the bigger screen with the other sketches you have discussed here.
For now I have a good project radio and fun. My advice is to look into what you purchased this kt for. The fun of building and experimentation, or just a cheep way to get a radio?

That's my tupence worth, so have fun 73s Vaughn

Re: HFSignals poor business practices

Curt
 

John

I saw reality everywhere except your title. I don't intend to scare you away, nor do others in this pile up.
The bitx and ubitx are incredible values. Not many in the world can afford or choose to purchase an expensive ssb capable rig. Build your rig and you will appreciate what is there.
Reasonable instruction is available on the web. International affordable shipping requires less paper.
Understand you can apply other microphone solutions.  Appreciate that someone without a rig receives enough material to put this rig on the air.
Let's recognize that this rig can be purchased by anyone. The world is much larger than our own nation and circumstances.  Appreciate the kind direct answers from the designer. Hope to see you again here with your design experiences.

Curt