Date   
Re: Isolate any jacks/controls from metal chassis? #ubitx

jim
 

Got mine from a "stained glass shop" 30 or so years ago ...are any of those things still around?

Jim

On Thursday, August 22, 2019, 4:54:45 PM UTC, jhowell39 via Groups.Io <jhowell39@...> wrote:


Electric guitar body cavities (pickup mounts, etc) often use a conductive copper tape for shielding.  If anyone is having a shielding issue with 3D printed cases or wood cases, this might be a good solution.  Available here.
--
73! de KJ7EZN   Jim

Re: Isolate any jacks/controls from metal chassis? #ubitx

Ian Reeve
 

We can buy this in the UK as a deterrent to slugs and snails guzzling our seedlings.I bought mine from a "*pound*" store in the gardening section


From: BITX20@groups.io <BITX20@groups.io> on behalf of jim via Groups.Io <ab7vf@...>
Sent: Thursday, August 22, 2019 6:08:28 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Isolate any jacks/controls from metal chassis? #ubitx
 
Got mine from a "stained glass shop" 30 or so years ago ...are any of those things still around?

Jim

On Thursday, August 22, 2019, 4:54:45 PM UTC, jhowell39 via Groups.Io <jhowell39@...> wrote:


Electric guitar body cavities (pickup mounts, etc) often use a conductive copper tape for shielding.  If anyone is having a shielding issue with 3D printed cases or wood cases, this might be a good solution.  Available here.
--
73! de KJ7EZN   Jim

moderated Re: QST September 2019 pg42 to 47

pat griffin
 

Jack,
You have made this argument before and each time it is well put. I’m with you buddy.
73
Pat AA4PG


On Aug 22, 2019, at 11:57 AM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:

This is an issue that hits home for me. One of my publishing companies has 3 people who's only job is to shut down torrent sites that allow free downloads of their books. Two years ago, they closed down over 2,000 sites that were downloading copyright material. They estimate that for every book I sell, three are downloaded illegally. We've even had universities point their students to these sites. It's impossible to stop them because the capital costs are little more than the cost of getting a domain name.

True, I'm out the royalties lost, but that's not the real cost of downloading/copying copyright material...regardless of the country's laws about it. The real cost are the books that don't come to the market because authors now know it's simply not worth the effort. If I were in it just for the money, I would have stopped writing around the turn of the century. We've even had readers on this site give the URL's of where my books can be downloaded free of charge. Since there is no way to stop them, my attitude now is: If you illegally download the book and read it, and decide it was worth it, then buy a copy of the book. I doubt there are many who follow this plan, but what else can an author do? It's a rock-hard-place situation.

Jack, W8TEE

On Thursday, August 22, 2019, 11:38:17 AM EDT, Arv Evans <arvid.evans@...> wrote:


The issue of posting something that might be under copyright does come up fairly frequently.
When this happens a lot of bandwidth is usually taken by those who charge in to protect the
copyright or patent, and not much ever comes of it.  Most do not know, or do not want to
admit, that for over half of the world copyrights and patents are irrelevant and are not enforced.
This makes it difficult or impossible to police violations in those countries.   Posting protected
material on a global forum like the BITX20 group seems to be a gray area because the person
posting the material may be in one of the unenforceable areas but the post can be read by
persons located in an enforceable area.  Best we can do is to ask that you do not post protected
material, and to remove those posts when it happens. 

Arv  K7HKL
_._


On Wed, Aug 21, 2019 at 11:00 PM kh6sky <kh6sky@...> wrote:
I have asked for permission from the ARRL to post an article from the early 60's and they refused to grant.  I am not optimistic about anything recent.  I have noted that QST authors sometimes post their articles on their own websites, for which I suppose they have permission, but don't know if it would be a work-around to go though the author and ask him to post it here.

moderated Re: QST September 2019 pg42 to 47

Dr. Flywheel
 

Everyone is entitled to their own opinion. The real question is what works in real life. Here are a few points to think about for people who insist on living in a virtual world:
  1. Many people use torrents to download books, in order to preview their content. This is due to the fact that public libraries are limited in their ability to purchase and keep all the books in the world in their limited physical space. Do not assume that if someone downloads your book, they actually keep it forever.
  2. I like previewing books prior to purchase. I also like physical books and my house is filled with them. I always purchase my books at bottom dollar, either "pre-owned" or "old stock". I use eBay, Amazon, B&N, etc for my purchase. As an author, you will not see a dime coming back to you through my purchase.
  3. Publishing for FREE has never stopped me from doing just that. If you are using the Internet, if you are using an Intel-based PC, if you are using Linux, if you are using an Android smart phone, if you are using WiFi technology, than you are using code, tools, and documents that I authored and/or contributed to maintain. I have never seen a dime coming back to me for my contributions, neither do I expect remuneration or royalties for my work.
  4. Many publishers act as a Mafia to squeeze a significant $$ by guarding the gates to publishing and physical distribution. When I went to college, my books cost between $3 and $10 each (Dover Edition). What is the justification for charging between $100 and $300 for a book used for educating university students and then changing the book edition every year to prevent resale of books (recycling)?
  5. Limiting information flow to the public will never work in today's world. the capabilities are there to distribute and share information by electronic means. This levels the playing field for all participants. The capabilities are orders of magnitude stronger than any laws on the books, as well as the ability to enforce such laws. Authors are better off being benevolent (open source) or offer their products at an enticing and fair price, or ask for voluntary pay from the consumer. There are already many people who take such attitude and being successful at dealing with reality.
  6. Student debt in the U.S.A is already $1.48 TRILLION. great part of that is attributed to the cost of books. Someone is getting rich in this system and typically it is not the authors.
 The world is constantly changing and sticking to old guns does not pay off. I suggest to stop whining and get on with your regularly scheduled programming...

--Ron   N7FTZ


On Thu, Aug 22, 2019 at 9:57 AM Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
This is an issue that hits home for me. One of my publishing companies has 3 people who's only job is to shut down torrent sites that allow free downloads of their books. Two years ago, they closed down over 2,000 sites that were downloading copyright material. They estimate that for every book I sell, three are downloaded illegally. We've even had universities point their students to these sites. It's impossible to stop them because the capital costs are little more than the cost of getting a domain name.

True, I'm out the royalties lost, but that's not the real cost of downloading/copying copyright material...regardless of the country's laws about it. The real cost are the books that don't come to the market because authors now know it's simply not worth the effort. If I were in it just for the money, I would have stopped writing around the turn of the century. We've even had readers on this site give the URL's of where my books can be downloaded free of charge. Since there is no way to stop them, my attitude now is: If you illegally download the book and read it, and decide it was worth it, then buy a copy of the book. I doubt there are many who follow this plan, but what else can an author do? It's a rock-hard-place situation.

Jack, W8TEE

On Thursday, August 22, 2019, 11:38:17 AM EDT, Arv Evans <arvid.evans@...> wrote:


The issue of posting something that might be under copyright does come up fairly frequently.
When this happens a lot of bandwidth is usually taken by those who charge in to protect the
copyright or patent, and not much ever comes of it.  Most do not know, or do not want to
admit, that for over half of the world copyrights and patents are irrelevant and are not enforced.
This makes it difficult or impossible to police violations in those countries.   Posting protected
material on a global forum like the BITX20 group seems to be a gray area because the person
posting the material may be in one of the unenforceable areas but the post can be read by
persons located in an enforceable area.  Best we can do is to ask that you do not post protected
material, and to remove those posts when it happens. 

Arv  K7HKL
_._


On Wed, Aug 21, 2019 at 11:00 PM kh6sky <kh6sky@...> wrote:
I have asked for permission from the ARRL to post an article from the early 60's and they refused to grant.  I am not optimistic about anything recent.  I have noted that QST authors sometimes post their articles on their own websites, for which I suppose they have permission, but don't know if it would be a work-around to go though the author and ask him to post it here.

Re: WSPR and APRS mobile

John (vk2eta)
 

Hello Ted,

Have you looked at JS8CALL?

It works on minimal HW like a PI, reports positions to APRS, allows precise locations with a variable length maiden locator format, uses the FT8 modulation for very low snr exchanges and it's messages simply spans as many 15 seconds transmit sequences as required.

73, John

moderated Re: QST September 2019 pg42 to 47

Jack, W8TEE
 

See below:
Jack, W8TEE

On Thursday, August 22, 2019, 1:48:25 PM EDT, Dr. Flywheel <Dr.Flywheel@...> wrote:


Everyone is entitled to their own opinion. The real question is what works in real life. Here are a few points to think about for people who insist on living in a virtual world:
  1. Many people use torrents to download books, in order to preview their content. Are you really saying that people only use torrent sites to preview books? Far and away most are using the site to get a free book and have no intention of paying for it regardless of its worth. To think otherwise is woefully naive. This is due to the fact that public libraries are limited in their ability to purchase and keep all the books in the world in their limited physical space. Do not assume that if someone downloads your book, they actually keep it forever. What difference can it possibly make whether they keep a free download book or not?
  2. I like previewing books prior to purchase. I also like physical books and my house is filled with them. I always purchase my books at bottom dollar, either "pre-owned" or "old stock". I use eBay, Amazon, B&N, etc for my purchase. As an author, you will not see a dime coming back to you through my purchase. However,  if you buy a used copy, at least someone bought the book and the author was paid for that copy. If you rip off a copy or someone gives you a file that contains the book, my guess is that copy has never been paid for.;
  3. Publishing for FREE has never stopped me from doing just that. If you are using the Internet, if you are using an Intel-based PC, if you are using Linux, if you are using an Android smart phone, if you are using WiFi technology, than you are using code, tools, and documents that I authored and/or contributed to maintain. I have never seen a dime coming back to me for my contributions, neither do I expect remuneration or royalties for my work. All of my work, including that in the Arduino Projects book is Open Source for both the hardware and software. So, in one sense I am paid for it, but in another I receive nothing for it. You're free to write what you want and disseminate it in whatever format you wish. However, publishers expect a return on their investment and I see nothing wrong with that.
  4. Many publishers act as a Mafia to squeeze a significant $$ by guarding the gates to publishing and physical distribution. When I went to college, my books cost between $3 and $10 each (Dover Edition). What is the justification for charging between $100 and $300 for a book used for educating university students and then changing the book edition every year to prevent resale of books (recycling)? There are many places where students can buy used books at reasonable prices. Perhaps one reason books are so expensive at university books stores is because publishers are getting ripped off by torrent sites. It could be a chicken-egg thing.
  5. Limiting information flow to the public will never work in today's world. the capabilities are there to distribute and share information by electronic means. This levels the playing field for all participants. The capabilities are orders of magnitude stronger than any laws on the books, as well as the ability to enforce such laws. Authors are better off being benevolent (open source) or offer their products at an enticing and fair price, or ask for voluntary pay from the consumer. There are already many people who take such attitude and being successful at dealing with reality. Do you get to determine "fair price"? Or perhaps the costs of development, editing, printing, binding, marketing, distribution and other costs play a more important part in determining a fair price. How do you know what my time is worth? Hint: You don't have a clue.
  6. Student debt in the U.S.A is already $1.48 TRILLION. great part of that is attributed to the cost of books Bullshit.. Someone is getting rich in this system and typically it is not the authors. Agreed, and torrent sites play a significant role.
 The world is constantly changing and sticking to old guns does not pay off. I suggest to stop whining and get on with your regularly scheduled programming...

--Ron   N7FTZ

On Thu, Aug 22, 2019 at 9:57 AM Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
This is an issue that hits home for me. One of my publishing companies has 3 people who's only job is to shut down torrent sites that allow free downloads of their books. Two years ago, they closed down over 2,000 sites that were downloading copyright material. They estimate that for every book I sell, three are downloaded illegally. We've even had universities point their students to these sites. It's impossible to stop them because the capital costs are little more than the cost of getting a domain name.

True, I'm out the royalties lost, but that's not the real cost of downloading/copying copyright material...regardless of the country's laws about it. The real cost are the books that don't come to the market because authors now know it's simply not worth the effort. If I were in it just for the money, I would have stopped writing around the turn of the century. We've even had readers on this site give the URL's of where my books can be downloaded free of charge. Since there is no way to stop them, my attitude now is: If you illegally download the book and read it, and decide it was worth it, then buy a copy of the book. I doubt there are many who follow this plan, but what else can an author do? It's a rock-hard-place situation.

Jack, W8TEE

On Thursday, August 22, 2019, 11:38:17 AM EDT, Arv Evans <arvid.evans@...> wrote:


The issue of posting something that might be under copyright does come up fairly frequently.
When this happens a lot of bandwidth is usually taken by those who charge in to protect the
copyright or patent, and not much ever comes of it.  Most do not know, or do not want to
admit, that for over half of the world copyrights and patents are irrelevant and are not enforced.
This makes it difficult or impossible to police violations in those countries.   Posting protected
material on a global forum like the BITX20 group seems to be a gray area because the person
posting the material may be in one of the unenforceable areas but the post can be read by
persons located in an enforceable area.  Best we can do is to ask that you do not post protected
material, and to remove those posts when it happens. 

Arv  K7HKL
_._


On Wed, Aug 21, 2019 at 11:00 PM kh6sky <kh6sky@...> wrote:
I have asked for permission from the ARRL to post an article from the early 60's and they refused to grant.  I am not optimistic about anything recent.  I have noted that QST authors sometimes post their articles on their own websites, for which I suppose they have permission, but don't know if it would be a work-around to go though the author and ask him to post it here.

Re: Isolate any jacks/controls from metal chassis? #ubitx

Gwen Patton
 

I used a spray-on conductive nickel coating inside my uBitX plastic case. It worked really well for shielding. I do recommend using a clear coat of lacquer over it, just a thin coating, to keep the nickel from flaking and landing on the PCB. You can always lightly sand a bit off at the edges where the case closes to keep shielding integrity. I have that copper foil tape, and it's very good, but I've been using it lately for small transmitting loop radiators.

73,
Gwen, NG3P

Re: Isolate any jacks/controls from metal chassis? #ubitx

Ian Reeve
 

I use the copper tape to shield wires that are suceptable to rf like the wires,taped to the case.Keeps them secure and screened as well. 


From: BITX20@groups.io <BITX20@groups.io> on behalf of Gwen Patton <ardrhi@...>
Sent: Thursday, August 22, 2019 7:30:05 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Isolate any jacks/controls from metal chassis? #ubitx
 
I used a spray-on conductive nickel coating inside my uBitX plastic case. It worked really well for shielding. I do recommend using a clear coat of lacquer over it, just a thin coating, to keep the nickel from flaking and landing on the PCB. You can always lightly sand a bit off at the edges where the case closes to keep shielding integrity. I have that copper foil tape, and it's very good, but I've been using it lately for small transmitting loop radiators.

73,
Gwen, NG3P

Re: Bitx40 very loud, high-pitched, low frequency noise

Woody
 

Glad to hear you got a handle on it!
Woody
--

moderated Re: QST September 2019 pg42 to 47

Hans Summers
 

Hi Dave

QRP Labs is not an advertiser in QST and never has been. 

I was shown a preview of the review in order to comment on any technical inaccuracies (altering the content i.e. the opinion of the reviewer, or disputing measurements, is not possible). Advertising space on a nearby page wasn't mentioned.

73 Hans G0UPL 

Re: Bitx40 very loud, high-pitched, low frequency noise

SP9DEV
 

I'll try to solder some caps to the power socket in bitx, some large ones nd some small ones for fast response. Maybe this will help.

Re: Bitx40 very loud, high-pitched, low frequency noise

Ian Reeve
 

So pleased that you are solving the issue of oscillation or instability.I run my uBITX from a 12 v battery and no problems.Won't run it from my shack 13.8 v power supply as that voltage is too high so I can't comment but would expect it to be stable.Anything less like these wall warts are not designed for running transcribers and will struggle to maintain the voltage and/ current.With inadequate smoothing capacitance,oscillation will be a problem.  Try adding a large value capacitor directly across the DC input. 



From: BITX20@groups.io <BITX20@groups.io> on behalf of Woody <woody@...>
Sent: Thursday, August 22, 2019 7:35:11 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Bitx40 very loud, high-pitched, low frequency noise
 
Glad to hear you got a handle on it!
Woody
--



Re: Bitx40 very loud, high-pitched, low frequency noise

SP9DEV
 

Wait a second, wouldn't soldering a large cap on a switched power supply create an overvoltage? As far as I remember, switch-mode supply units create low voltage by switching higher voltage on and off, and the output is just an average voltage of the pwm. Or am i wrong?

Re: Bitx40 very loud, high-pitched, low frequency noise

Ian Reeve
 

In my experience,no,but I stand to be corrected.By large capacitance I mean say 100uf,I have done this with no issues.You are quite correct in your description but the switching does not take place right at the output,there is regulation etc built in.A linear supply is a better option but has to be. Well made and designed for it to work properly and keep within its output voltage.


From: BITX20@groups.io <BITX20@groups.io> on behalf of SP9DEV <piotrekslawecki2@...>
Sent: Thursday, August 22, 2019 7:50:28 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Bitx40 very loud, high-pitched, low frequency noise
 
Wait a second, wouldn't soldering a large cap on a switched power supply create an overvoltage? As far as I remember, switch-mode supply units create low voltage by switching higher voltage on and off, and the output is just an average voltage of the pwm. Or am i wrong?

Re: Bitx40 very loud, high-pitched, low frequency noise

Woody
 

No and yes...   A short answer..  The voltage sense of the switcher should reduce the duty cycle to compensate for any filter cap added.  The only problem may be the initial current generated by charging the extra cap may exceed the current capacity of the supply.  Many supplies have current limiting also.  If this is the case, no problems.
Woody
--

Re: Bitx40 very loud, high-pitched, low frequency noise

SP9DEV
 

Alright, I'll try with a 1000uF capacitor, first I'll measure the output voltage with the capacitor between + and gnd lines of the supply output, then I'll give it a try with my bitx by soldering the cap directly across the dc input (I think adding a small cap parallel to the large cap will be beneficial too, as the small one will have faster response time)

Re: Bitx40 very loud, high-pitched, low frequency noise

Ian Reeve
 

I think that 1000uf is too large.

 

Try a 100uf and a 0.1uf in parallel. The larger adding more smoothing and the latter decoupling any RF and noise to ground.

 

Monitor output voltage before and after but I have had no problems with voltage increase. It all depends on what you are using as the power supply and it is open for experimentation.

 

A 1000uf would cause too high a current at switch-on (surge) and may well damage the power supply.

Start at 100uf and work up to say 250uf. If that doesn’t settle things down,I guess you need a more robust 12v supply.

 

Ian

M0IDR

 

Sent from Mail for Windows 10

 


From: BITX20@groups.io <BITX20@groups.io> on behalf of SP9DEV <piotrekslawecki2@...>
Sent: Thursday, August 22, 2019 8:05:25 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Bitx40 very loud, high-pitched, low frequency noise
 
Alright, I'll try with a 1000uF capacitor, first I'll measure the output voltage with the capacitor between + and gnd lines of the supply output, then I'll give it a try with my bitx by soldering the cap directly across the dc input (I think adding a small cap parallel to the large cap will be beneficial too, as the small one will have faster response time)

Re: Bitx40 very loud, high-pitched, low frequency noise

Ian Reeve
 

Just to add a bit more to this thread, I have just taken a typical 12v “wall wart” supply that is of Oriental origin and put a oscilloscope directly across the output. There are some nasty spikes on the DC output that are larger than the 12v output. As an experiment I then put a 100uf 50v across the output and the DC became much cleaner with less pronounced spikes. Adding a 0.1uf across,stopped these spikes and made the output acceptable. The output DC did not change by more than a few millivolts.

Just a quick experiment using a random “wall wart” from my collection of such items from discarded equipment.

 

Ian

 

Sent from Mail for Windows 10

 


From: BITX20@groups.io <BITX20@groups.io> on behalf of Ian Reeve <ian.radioworkshop@...>
Sent: Thursday, August 22, 2019 8:29:00 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Bitx40 very loud, high-pitched, low frequency noise
 

I think that 1000uf is too large.

 

Try a 100uf and a 0.1uf in parallel. The larger adding more smoothing and the latter decoupling any RF and noise to ground.

 

Monitor output voltage before and after but I have had no problems with voltage increase. It all depends on what you are using as the power supply and it is open for experimentation.

 

A 1000uf would cause too high a current at switch-on (surge) and may well damage the power supply.

Start at 100uf and work up to say 250uf. If that doesn’t settle things down,I guess you need a more robust 12v supply.

 

Ian

M0IDR

 

Sent from Mail for Windows 10

 


From: BITX20@groups.io <BITX20@groups.io> on behalf of SP9DEV <piotrekslawecki2@...>
Sent: Thursday, August 22, 2019 8:05:25 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] Bitx40 very loud, high-pitched, low frequency noise
 
Alright, I'll try with a 1000uF capacitor, first I'll measure the output voltage with the capacitor between + and gnd lines of the supply output, then I'll give it a try with my bitx by soldering the cap directly across the dc input (I think adding a small cap parallel to the large cap will be beneficial too, as the small one will have faster response time)

Re: Bitx40 very loud, high-pitched, low frequency noise

SP9DEV
 

I have some 100uf 50V on hand, added one across bitx40 dc socket, unfortunately the problem persists. I don't have any small caps right now, tomorrow I'll add a small cap and let you guys know if this helped the case.

Re: Bitx40 very loud, high-pitched, low frequency noise

Woody
 

On 8/22/2019 19:05, SP9DEV wrote:
(I think adding a small cap parallel to the large cap will be beneficial too, as the small one will have faster response time)
That is very true.  The large caps (like 1000+ uf) are good for low frequencies but often the ESR (effective series resistance) is quite high for high frequencies.  A serveral thousand uf cap in parallel with a ceramic .1 or .01 uf (with short leads) is the ideal combination.   Ferrite sleeves can help with common mode RFI coming from a switcher also.
Woody

--