Date   
Re: How do I best operate a 4S-Tuner with a Doublet antenna ?

Frank Perkins
 

Hi Bob,
Antennas are the magic part of ham radio.
Your 4sqrp tuner is a great one, basically designed for use with a "random length wire" antenna and a counterpoise wire.
For portable use, the antenna could be anywhere from 20 to 80 feet, and the counterpoise from 4 to 15 feet.
The antenna wire on the red binding post and counterpoise on the black post.
However, you are using a dipole antenna with a balanced feedline.
I would first try it connected to the red & black binding posts, and see what results you get (signal strength and direction determined by call zones received). Then switch the feedline wires and test again. Then twist both feedline wires together onto the red post and a 10 ft counterpoise wire on the black post.
Compare data. Which gave best results?
A typical dipole at about 40 ft off the ground running North and South will have the best coverage to the East and West. If only 10 to 12 feet high, it will be NVIS and work best on 40, 80, & 160, and give omnidirectional 300-500 mile range.
Later, you can build a little 1:1 and 4:1 BALUN to try between the feedline pair and the posts.
That's the fun of antennas.
I don't think you mentioned what type of rig you have, but if it's portable, take it to a park with a spool of lightweight wire.
Take a fishing pole with a 1-1/2oz sinker, sling it into a tree, pull the end of the antenna wire into the tree and have a blast!
Cheers,
Frank N6CES

On Tue, Apr 16, 2019, 6:58 AM Bob KM6BMX <km6bmx@...> wrote:
Hi all,

  Thanks for the replies.

  Frank, you mentioned a 4:1 balun. If I am connecting the 2-wire feedline directly to the tuner binding posts, how do I make / find a "bal-bal"? Or, are you suggesting that I use an actual 4:1 balun (2-wire feedline on one side, coax connector on the other side, and multiple turns of coax in between) and hook that to the coax antenna connector on the tuner?

  If I understand correctly, at 40m the Doublet will present roughly 50 ohms to the tuner. Since I can dial out most of the inductance and capacitance with the 3 knobs, I should be able to match with low SWR fairly quickly. 

  At harmonic shorter bands (20m, 15m, 10m), the Doublet will likely present with a higher impedance. Then, I can dial in increasing amounts of inductance and capacitance to match the antenna to the transceiver operating at the higher frequencies.

  I think that the tuner will really shine with some of other HF bands (30m, 17m, 12m). At those frequencies,  the Doublet will truly present as a "random wire".

  As you all say, I will know when I try it. Now that I have a feasible and highly portable antenna and tuner, I need to find a small HF transceiver to actually operate. Perhaps I can bring it to a Field Day or other operating event somewhere in central AZ and ask if I can try it with one of their rigs. 

  For my own rig, I am waiting until Hans Summer releases his QSX multi-mode all-HF band QRP transceiver. I Hopefully, his QRP Labs ( http://www.qrp-labs.com ) will make those available sometime this summer of 2019. 

  I am not yet CW capable and won't have time to learn Morse code anytime soon. Thus, I need a rig that supports SSB and maybe even some of the digital modes ( RTTY, PSK31, Olivia, FT-x, etc.)

Cheers & 73,
Bob KM6BMX
--  central AZ

Re: Eagle Parts Library for QRP projects?

Nick WA5BDU
 

I've found the same thing, Curt. Using ExpressPCB to make SMT toner transfer designs, the footprints that are standard are no-doubt fine for machine assembly or paste & heat, but if you are using a soldering iron you long for a bit more room to put down your soldering iron tip and solder without disturbing the part. 

Those little SOT23-3 transistors and regulators are especially difficult. But even big ole 1206 parts can benefit from a bit more foil. So I do make a lot of custom parts, sometimes starting with what came with the program and making the pads larger if there's room.


73-

Nick, WA5BDU

Re: Eagle Parts Library for QRP projects?

Mike D
 

The Sparkfun libraries are a good resource for getting started. 

I use Eagle extensively, and generally Mouser has libraries available for most parts they stock.  I usually order most of my components from there anyways, so it's a good resource.

Mike kd5rjz

On Tue, Apr 16, 2019 at 11:28 AM Curt via Groups.Io <rhulett1=consolidated.net@groups.io> wrote:
Well, as it happens, just now found the SparkFun libraries https://www.sparkfun.com/EAGLE , which look promising.  Not sure how missed these. I am going to wander through those parts to see what the footprints are like.  Also that site seems to have some tutorials that ought to be useful.

Curt KB5JO

Re: Eagle Parts Library for QRP projects?

Curt
 

Well, as it happens, just now found the SparkFun libraries https://www.sparkfun.com/EAGLE , which look promising.  Not sure how missed these. I am going to wander through those parts to see what the footprints are like.  Also that site seems to have some tutorials that ought to be useful.

Curt KB5JO

Re: Anti Static soldering mats

W4OED
 

Bob,

ESD mats are for benchtop usage.

The same applies to the Craft E Mat or the Kasis S-140 previously mentioned before.

Large ESD floor mats or even ESD floor paint exist, but they are mostly for production areas and repair shops. In this case, technical personnel wear ESD ankle straps over their shoes to discharge static electricity to the floor.

Oscar
W4OED

Quoting Bob Parr <parr@...>:

Is the idea to use this on a bench as a work surface or on the floor under your feet?

Bob
KG5GTE

I had problems following the links. I went to Amazon and searched
for Bertech Rubber ESD and there you go........ all kinds of
choices.

Thanks Bill for that info, used these years ago but here in Florida
especially during the summer there's not much static if you're shop
isn't air conditioned!! I may get the 18 x 24 one for my winter
projects.


John
KK4ITX

If you need a parachute and don't have one you probably won't need
one again.

On Apr 15, 2019, at 18:39, W4OED <w4oed@...> wrote:


Hi there,

I sensed that there was a bit of confusion regarding ESD mats and
I would like to clarify a few things, if I may. BTW, I work at an
electronics equipment factory and I wear an ESD wrist wrap and an
ESD lab coat when writing and verifying the testing procedures
for our products.

The Craft E Mat may be good as a work bench protector and
components gathering device, but it is not ESD compliant.

Here you have an example of a true ESD mat:

https://www.amazon.com/Bertech-Temperature-Rubber-Wrist-
Grounding/dp/B01KT3YPPS/ref=sr_1_1_sspa?
crid=WH16OYYVTSYC&keywords=esd+mat+kit+with+a+wrist+strap+and+groundin
g+cord &qid=1555363698&s=gateway&sprefix=ESD+mat%2Caps%2C200&sr=8-
1-spons&psc=1

In any event, ESD compliant mats and wrist straps are only
necessary when working with ESD sensitive devices, such as MOSFET
transistors, computer ICs, RAM memory sticks, some LEDs (laser
and UV), and CMOS ICs. Most TTL ICs
and bipolar transistors are quite resilient to ESD.

For the most part, when the ESD sensitive devices are soldered or
connected to the PCB, they become more resilient to ESD. When the
PCB carrying those devices is connected to the rest of the
equipment, only some I/O ports may still be ESD sensitive.

ESD compliant mats have a high-resistance top layer that
dissipates static electricity by sending it to a ground
connection. This ground can be the ground terminal of a nearby ac
socket or a dedicated low-resistance earth ground rod. The wrist
strap works in a similar fashion.

73!

Original email:
-----------------
From: wohlsson . wohlsson@...
Date: Sun, 14 Apr 2019 21:00:45 -0400
To: main@4sqrp.groups.io
Subject: Re: [4SQRP] Anti Static soldering mats


Opps...forgot the link

https://www.amazon.com/Craft-Mat-Oversize-Worry-
Silicone/dp/B07GBFRCJY/ref=sr_1_1?
keywords=craftemat&qid=1555288975&s=gateway&sr=8-1


Bill...wa8bda

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On Sun, Apr 14, 2019 at 8:58 PM wohlsson . via Groups.Io
<wohlsson= gmail.com@groups.io> wrote:

Yes, these silicone mats are nice for bench work/kit building.
I have been

using the one

below now for a few months. Grand kids orginally bought one for
craft

projects and I was

attracted to the large 1/2" sides to contain things. Also the
large

working area allow me to

also place test equipment/tools on the work area and still have
lots of

space. I use a anti-static

wrist band when needed.


Bill.....wa8bda


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On Sun, Apr 14, 2019 at 6:55 PM Tim McDonough N9PUZ
<tim.n9puz@...>

wrote:


We have rolls of material that look similar at work. They cut
it to size
for the work area but then the corner gets punched and a snap
terminal
installed which has a lead connecting it to ground.


I've been starting to look for a small anti-static mat for my
home bench
and these that were mentioned look nice since they have the
raised edge
to
help keep things from escaping.


Tim N9PUZ


On 4/14/2019 5:05 PM, AG1P Ron wrote:


I was wondering same thing - From Amazon page -


?This is silicone anti static mat, but its just static
resistant, If
you
want ESD protection with your body, you can use it with an
anti static
wrist band


72 - Ron - AG1P


*From:* main@4SQRP.groups.io [mailto:main@4SQRP.groups.io
<main@4SQRP.groups.io>] *On Behalf Of *Tim McDonough N9PUZ
*Sent:* Sunday, April 14, 2019 2:54 PM
*To:* main@4SQRP.groups.io
*Subject:* Re: [4SQRP] Anti Static soldering mats


Any idea if these mats are anti-static as well?


Tim N9PUZ


On 4/14/2019 2:02 PM, Virginia R Smith wrote:


Hi Everybody!


It's Virginia NV5F


I met some of you guys at Ozarkcon and had a great time! I
hope I can
make it back next year.


During the kit building Joe and I were using these nifty blue
silicone
soldering mats. I think there will be something on them in
April CQ.


Anyway I was asked to provide information on them here. I
actually head
about them from Bob Heil on Ham Nation. Apparently Heil Sound
has started
using them. They are used by technicians to repair cell
phones and small
electronics but they work great for building kits! They are
good for ESD
and aren't affected by hot solder. They also have magnets
that will hold
little parts in place until they are needed. The magnets also
help the
mat
stick to a cookie sheet!


And I got them on Amazon!


Kaisi S-140 magnetic insulation soldering mat


They come in several sizes. The S-140 fits perfect in a
medium steel
cookie sheet from Wal Mart! And I find that when it gets
overrun with
leads and solder blobs you can clean it off with a piece of
masking tape.
And if you need to move your work just pick up the cookie
sheet. Also the
silicone makes for a nice quiet work surface.


Hope this helps everyone have even more fun building stuff!


Hope to see some of y'all in Dayton.


72
Virginia NV5F

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Re: Anti Static soldering mats

Bob Parr
 

Is the idea to use this on a bench as a work surface or on the floor under your feet?
 
Bob
KG5GTE

> I had problems following the links.  I went to Amazon and searched
> for Bertech Rubber ESD and there you go........ all kinds of
> choices.
>
> Thanks Bill for that info, used these years ago but here in Florida
> especially during the summer there's not much static if you're shop
> isn't air conditioned!!  I may get the 18 x 24 one for my winter
> projects.
>
>
> John
> KK4ITX 
>
> If you need a parachute and don't have one you probably won't need
> one again.
>
> On Apr 15, 2019, at 18:39, W4OED <w4oed@...> wrote:
>
>
>> Hi there,
>>
>> I sensed that there was a bit of confusion regarding ESD mats and
>> I would like to clarify a few things, if I may. BTW, I work at an
>> electronics equipment factory and I wear an ESD wrist wrap and an
>> ESD lab coat when writing and verifying the testing procedures
>> for our products.
>>
>> The Craft E Mat may be good as a work bench protector and
>> components gathering device, but it is not ESD compliant.
>>
>> Here you have an example of a true ESD mat:
>>
>> Grounding/dp/B01KT3YPPS/ref=sr_1_1_sspa?
>> crid=WH16OYYVTSYC&keywords=esd+mat+kit+with+a+wrist+strap+and+groundin
>> g+cord &qid=1555363698&s=gateway&sprefix=ESD+mat%2Caps%2C200&sr=8-
>> 1-spons&psc=1
>>
>> In any event, ESD compliant mats and wrist straps are only
>> necessary when working with ESD sensitive devices, such as MOSFET
>> transistors, computer ICs, RAM memory sticks, some LEDs (laser
>> and UV), and CMOS ICs. Most TTL ICs
>> and bipolar transistors are quite resilient to ESD.
>>
>> For the most part, when the ESD sensitive devices are soldered or
>> connected to the PCB, they become more resilient to ESD. When the
>> PCB carrying those devices is connected to the rest of the
>> equipment, only some I/O ports may still be ESD sensitive.
>>
>> ESD compliant mats have a high-resistance top layer that
>> dissipates static electricity by sending it to a ground
>> connection. This ground can be the ground terminal of a nearby ac
>> socket or a dedicated low-resistance earth ground rod. The wrist
>> strap works in a similar fashion.
>>
>> 73!
>>
>> Original email:
>> -----------------
>> From: wohlsson . wohlsson@...
>> Date: Sun, 14 Apr 2019 21:00:45 -0400
>> To: main@4sqrp.groups.io
>> Subject: Re: [4SQRP] Anti Static soldering mats
>>
>>
>> Opps...forgot the link
>>
>> Silicone/dp/B07GBFRCJY/ref=sr_1_1?
>> keywords=craftemat&qid=1555288975&s=gateway&sr=8-1
>>
>>
>> Bill...wa8bda
>>
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=icon> Virus-free.
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=link> <#DAB4FAD8-2DD7-40BB-
>> A1B8-4E2AA1F9FDF2>
>>
>> On Sun, Apr 14, 2019 at 8:58 PM wohlsson . via Groups.Io
>> <wohlsson= gmail.com@groups.io> wrote:
>>
>>> Yes, these silicone mats are nice for bench work/kit building.
>>> I have been
>>>
>>> using the one
>>>
>>> below now for a few months. Grand kids orginally bought one for
>>> craft
>>>
>>> projects and I was
>>>
>>> attracted to the large 1/2" sides to contain things. Also the
>>> large
>>>
>>> working area allow me to
>>>
>>> also place test equipment/tools on the work area and still have
>>> lots of
>>>
>>> space. I use a anti-static
>>>
>>> wrist band when needed.
>>>
>>>
>>> Bill.....wa8bda
>>>
>>>
>>>
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=icon> Virus-free.
>>
>>> www.avast.com
>>>
>>>
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=link>
>>
>>> <#m_1504296041646331162_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>>>
>>>
>>> On Sun, Apr 14, 2019 at 6:55 PM Tim McDonough N9PUZ
>>> <tim.n9puz@...>
>>>
>>> wrote:
>>>
>>>
>>>> We have rolls of material that look similar at work. They cut
>>>> it to size
>>>>
>>>
>>>> for the work area but then the corner gets punched and a snap
>>>> terminal
>>>>
>>>
>>>> installed which has a lead connecting it to ground.
>>>>
>>>>
>>>> I've been starting to look for a small anti-static mat for my
>>>> home bench
>>>>
>>>
>>>> and these that were mentioned look nice since they have the
>>>> raised edge
>>>>
>>>
>> to
>>>> help keep things from escaping.
>>>>
>>>>
>>>> Tim N9PUZ
>>>>
>>>>
>>>> On 4/14/2019 5:05 PM, AG1P Ron wrote:
>>>>
>>>>
>>>> I was wondering same thing - From Amazon page -
>>>>
>>>>
>>>> ?This is silicone anti static mat, but its just static
>>>> resistant, If
>>>>
>>>
>> you
>>>> want ESD protection with your body, you can use it with an
>>>> anti static
>>>>
>>>
>>>> wrist band
>>>>
>>>>
>>>> 72 - Ron - AG1P
>>>>
>>>>
>>>> *From:* main@4SQRP.groups.io [mailto:main@4SQRP.groups.io
>>>>
>>>
>>>> <main@4SQRP.groups.io>] *On Behalf Of *Tim McDonough N9PUZ
>>>>
>>>
>>>> *Sent:* Sunday, April 14, 2019 2:54 PM
>>>>
>>>
>>>> *To:* main@4SQRP.groups.io
>>>>
>>>
>>>> *Subject:* Re: [4SQRP] Anti Static soldering mats
>>>>
>>>>
>>>> Any idea if these mats are anti-static as well?
>>>>
>>>>
>>>> Tim N9PUZ
>>>>
>>>>
>>>> On 4/14/2019 2:02 PM, Virginia R Smith wrote:
>>>>
>>>>
>>>> Hi Everybody!
>>>>
>>>>
>>>> It's Virginia NV5F
>>>>
>>>>
>>>> I met some of you guys at Ozarkcon and had a great time! I
>>>> hope I can
>>>>
>>>
>>>> make it back next year.
>>>>
>>>>
>>>> During the kit building Joe and I were using these nifty blue
>>>> silicone
>>>>
>>>
>>>> soldering mats. I think there will be something on them in
>>>> April CQ.
>>>>
>>>>
>>>> Anyway I was asked to provide information on them here. I
>>>> actually head
>>>>
>>>
>>>> about them from Bob Heil on Ham Nation. Apparently Heil Sound
>>>> has started
>>>>
>>>
>>>> using them. They are used by technicians to repair cell
>>>> phones and small
>>>>
>>>
>>>> electronics but they work great for building kits! They are
>>>> good for ESD
>>>>
>>>
>>>> and aren't affected by hot solder. They also have magnets
>>>> that will hold
>>>>
>>>
>>>> little parts in place until they are needed. The magnets also
>>>> help the
>>>>
>>>
>> mat
>>>> stick to a cookie sheet!
>>>>
>>>>
>>>> And I got them on Amazon!
>>>>
>>>>
>>>> Kaisi S-140 magnetic insulation soldering mat
>>>>
>>>>
>>>> They come in several sizes. The S-140 fits perfect in a
>>>> medium steel
>>>>
>>>
>>>> cookie sheet from Wal Mart!  And I find that when it gets
>>>> overrun with
>>>>
>>>
>>>> leads and solder blobs you can clean it off with a piece of
>>>> masking tape.
>>>>
>>>
>>>> And if you need to move your work just pick up the cookie
>>>> sheet. Also the
>>>>
>>>
>>>> silicone makes for a nice quiet work surface.
>>>>
>>>>
>>>> Hope this helps everyone have even more fun building stuff!
>>>>
>>>>
>>>> Hope to see some of y'all in Dayton.
>>>>
>>>>
>>>> 72
>>>>
>>>
>>>> Virginia NV5F
>>>
>>>
>>>
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=icon> Virus-free.
>>
>>> www.avast.com
>>>
>>>
>> utm_medium=email&utm_source=link&utm_campaign=sig-
>> email&utm_content=webmail&utm_term=link>
>>
>>> <#m_1504296041646331162_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>>
>>
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>>
>>

Re: Eagle Parts Library for QRP projects?

Dave NZ1J
 

Hi Curt,
 
Like you, I prefer to have enough copper on the board to be able to work with it easily.
 
For something like a DIP package, the lead spacing is 0.100"  The drilled holes are about 0.040"  That leaves 0.060" of fiberglass between the holes.  If 0.020" annular rings are used around each hole, that leaves 0.020" of space between the rings.
 
As you say, modern manufacturing uses pretty tight tolerances.  To pass a trace between those DIP pads, things need to be squeezed a bit.  I think the standard libraries may allow room for that trace as the default.  Though it is some extra work for us, customizing the rings to be larger where possible makes for a board that is more tolerant of some rework.  We can also use oblong pads that leave room for the trace, but provide more copper where there isn't an issue.
 
I also choose wide traces wherever possible.  Sometimes the default is 0.012" or even narrower.
 
I'm sorry that I don't know of any libraries that will do what we want.  Please let us all know what you find.
 
73,
Dave NZ1J


---------- Original Message ----------
From: "Curt via Groups.Io" <rhulett1@...>
To: main@4SQRP.groups.io
Subject: [4SQRP] Eagle Parts Library for QRP projects?
Date: Tue, 16 Apr 2019 08:16:37 -0700

At age 71, decided to attempt learning how to design a PCB for fabrication by the numerous available shops.  Selected Eagle, using the free version at least for starting, managed to draw a schematic and produce a board design for a simple crystal transmitter using parts from the numerous available libraries.  Managed to build one "device" in a personal "library".  When the fabricated board arrived, unfortunately the parts pads weren't as large as I wanted, and the device I had built was larger than would have liked.  The board is likely usable, but nothing would care to share.

So, back to the drawing board.

I think the defaults in the program aren't what an amateur should use, but am not sure what the defaults should be.  For example, default design rules for pad around hole has a minimum of 10 mils and maximum of 20 mils.  What should they be?   

I think the parts vendor libraries are voluminous and targeted toward commercially designed PCBs.

With the many  PCBs designed and fabricated for QRP projects, there are libraries already populated with parts appropriately scaled for the parts that we use with QRP projects.   I have looked unsuccessfully for such a library.  I could build my own of course, but not sure of the value reinventing that wheel.

Is there a resource for QRP PCB design rules and library?  Or is every hobbyist rolling their own?

73, Curt KB5JO



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Eagle Parts Library for QRP projects?

Curt
 

At age 71, decided to attempt learning how to design a PCB for fabrication by the numerous available shops.  Selected Eagle, using the free version at least for starting, managed to draw a schematic and produce a board design for a simple crystal transmitter using parts from the numerous available libraries.  Managed to build one "device" in a personal "library".  When the fabricated board arrived, unfortunately the parts pads weren't as large as I wanted, and the device I had built was larger than would have liked.  The board is likely usable, but nothing would care to share.

So, back to the drawing board.

I think the defaults in the program aren't what an amateur should use, but am not sure what the defaults should be.  For example, default design rules for pad around hole has a minimum of 10 mils and maximum of 20 mils.  What should they be?   

I think the parts vendor libraries are voluminous and targeted toward commercially designed PCBs.

With the many  PCBs designed and fabricated for QRP projects, there are libraries already populated with parts appropriately scaled for the parts that we use with QRP projects.   I have looked unsuccessfully for such a library.  I could build my own of course, but not sure of the value reinventing that wheel.

Is there a resource for QRP PCB design rules and library?  Or is every hobbyist rolling their own?

73, Curt KB5JO

Re: Anti Static soldering mats

W4OED
 

Hi there,

My apologies for responding to this posting after having responded to a
much
later one before.

I did investigate the Kaisi S-140 mat offered by Amazon.

Not only it is neat, it is also very well designed.

However, it is NOT ESD compatible.

Even the product description says so:

"Attention:

&#9733;This is silicone anti static mat, but its just static resistant, If
you
want ESD protection with your body, you can use it with an anti static
wrist
band."

If you have one of these mats and want to handle static sensitive boards or
devices, get an ESD compatible wrist strap (https://www.amazon.com/s?
k=ESD+wrist+strap&i=tools&ref=nb_sb_noss_2).

Just make sure to connect it to the ground terminal of the nearest ac
outlet
and wear it whenever you handle ESD sensitive items.

BTW, I ordered the Kaisi S-140 magnetic mat and a couple of ESD wrist
straps. Sweet!

73!

Original email:
-----------------
From: Virginia R Smith virginia@...
Date: Sun, 14 Apr 2019 14:02:36 -0500
To: 4SQRP@groups.io
Subject: [4SQRP] Anti Static soldering mats


Hi Everybody!

It's Virginia NV5F

I met some of you guys at Ozarkcon and had a great time! I hope I can make
it back next year.

During the kit building Joe and I were using these nifty blue silicone
soldering mats. I think there will be something on them in April CQ.

Anyway I was asked to provide information on them here. I actually head
about them from Bob Heil on Ham Nation. Apparently Heil Sound has started
using them. They are used by technicians to repair cell phones and small
electronics but they work great for building kits! They are good for ESD
and
aren't affected by hot solder. They also have magnets that will hold little
parts in place until they are needed. The magnets also help the mat stick
to
a cookie sheet!

And I got them on Amazon!

Kaisi S-140 magnetic insulation soldering mat

They come in several sizes. The S-140 fits perfect in a medium steel cookie
sheet from Wal Mart! And I find that when it gets overrun with leads and
solder blobs you can clean it off with a piece of masking tape. And if you
need to move your work just pick up the cookie sheet. Also the silicone
makes for a nice quiet work surface.

Hope this helps everyone have even more fun building stuff!

Hope to see some of y'all in Dayton.

72
Virginia NV5F




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Re: How do I best operate a 4S-Tuner with a Doublet antenna ?

Bob KM6BMX
 

Hi all,

  Thanks for the replies.

  Frank, you mentioned a 4:1 balun. If I am connecting the 2-wire feedline directly to the tuner binding posts, how do I make / find a "bal-bal"? Or, are you suggesting that I use an actual 4:1 balun (2-wire feedline on one side, coax connector on the other side, and multiple turns of coax in between) and hook that to the coax antenna connector on the tuner?

  If I understand correctly, at 40m the Doublet will present roughly 50 ohms to the tuner. Since I can dial out most of the inductance and capacitance with the 3 knobs, I should be able to match with low SWR fairly quickly. 

  At harmonic shorter bands (20m, 15m, 10m), the Doublet will likely present with a higher impedance. Then, I can dial in increasing amounts of inductance and capacitance to match the antenna to the transceiver operating at the higher frequencies.

  I think that the tuner will really shine with some of other HF bands (30m, 17m, 12m). At those frequencies,  the Doublet will truly present as a "random wire".

  As you all say, I will know when I try it. Now that I have a feasible and highly portable antenna and tuner, I need to find a small HF transceiver to actually operate. Perhaps I can bring it to a Field Day or other operating event somewhere in central AZ and ask if I can try it with one of their rigs. 

  For my own rig, I am waiting until Hans Summer releases his QSX multi-mode all-HF band QRP transceiver. I Hopefully, his QRP Labs ( http://www.qrp-labs.com ) will make those available sometime this summer of 2019. 

  I am not yet CW capable and won't have time to learn Morse code anytime soon. Thus, I need a rig that supports SSB and maybe even some of the digital modes ( RTTY, PSK31, Olivia, FT-x, etc.)

Cheers & 73,
Bob KM6BMX
--  central AZ

SSS Results

John Lonigro
 

There were 12 entries this month, including several new participants, a fine showing.  Maybe everybody is still pumped up over Ozarkcon.  A big welcome to Steve (WB5CTS) and George (K3EMS). If my records are correct, these two are first time entrants in the SSS.  Also, Paul (N0NBD), Bob (K0FHG), Terry (WA0ITP), and Paul (WA9PWP) made their first entries for 2019.  Welcome back, gentlemen.

The winner for April is Carl (WB0CFF) with 20 points, followed by Chas (W2SH) with 15 points.  We have reached the 1/3 point for the 2019 contest.  The overall leader is Chas (W2SH) with 52 points.  In second place is Nick (WB5BKL) - 45 points.  In third place is Carl (WB5CFF) - 38 points.

Carl will receive his April certificate via email shortly, once I create it.

The May SSS probably conflicts with Mother's Day.  It does every year.  You've got a month to figure out what to give the XYL in exchange for a couple of hours on the radio that night.  You have been warned!

72 until next month,

John, AA0VE
4SQRP Contest Coordinator

Re: Anti Static soldering mats

John - KK4ITX
 

I had problems following the links.  I went to Amazon and searched for Bertech Rubber ESD and there you go........ all kinds of choices.

Thanks Bill for that info, used these years ago but here in Florida especially during the summer there’s not much static if you’re shop isn’t air conditioned!!  I may get the 18 x 24 one for my winter projects.

John
KK4ITX 

If you need a parachute and don't have one you probably won't need one again.

On Apr 15, 2019, at 18:39, W4OED <w4oed@...> wrote:

Hi there,

I sensed that there was a bit of confusion regarding ESD mats and I would
like to clarify a few things, if I may. BTW, I work at an electronics
equipment factory and I wear an ESD wrist wrap and an ESD lab coat when
writing and verifying the testing procedures for our products.

The Craft E Mat may be good as a work bench protector and components
gathering device, but it is not ESD compliant.

Here you have an example of a true ESD mat:

https://www.amazon.com/Bertech-Temperature-Rubber-Wrist-
Grounding/dp/B01KT3YPPS/ref=sr_1_1_sspa?
crid=WH16OYYVTSYC&keywords=esd+mat+kit+with+a+wrist+strap+and+grounding+cord
&qid=1555363698&s=gateway&sprefix=ESD+mat%2Caps%2C200&sr=8-1-spons&psc=1

In any event, ESD compliant mats and wrist straps are only necessary when
working with ESD sensitive devices, such as MOSFET transistors, computer
ICs, RAM memory sticks, some LEDs (laser and UV), and CMOS ICs. Most TTL
ICs
and bipolar transistors are quite resilient to ESD.

For the most part, when the ESD sensitive devices are soldered or connected
to the PCB, they become more resilient to ESD. When the PCB carrying those
devices is connected to the rest of the equipment, only some I/O ports may
still be ESD sensitive.

ESD compliant mats have a high-resistance top layer that dissipates static
electricity by sending it to a ground connection. This ground can be the
ground terminal of a nearby ac socket or a dedicated low-resistance earth
ground rod. The wrist strap works in a similar fashion.

73!

Original email:
-----------------
From: wohlsson . wohlsson@...
Date: Sun, 14 Apr 2019 21:00:45 -0400
To: main@4sqrp.groups.io
Subject: Re: [4SQRP] Anti Static soldering mats


Opps...forgot the link

https://www.amazon.com/Craft-Mat-Oversize-Worry-
Silicone/dp/B07GBFRCJY/ref=sr_1_1?
keywords=craftemat&qid=1555288975&s=gateway&sr=8-1



Bill...wa8bda

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On Sun, Apr 14, 2019 at 8:58 PM wohlsson . via Groups.Io <wohlsson=
gmail.com@groups.io> wrote:

Yes, these silicone mats are nice for bench work/kit building. I have been
using the one
below now for a few months. Grand kids orginally bought one for craft
projects and I was
attracted to the large 1/2" sides to contain things. Also the large
working area allow me to
also place test equipment/tools on the work area and still have lots of
space. I use a anti-static
wrist band when needed.

Bill.....wa8bda


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On Sun, Apr 14, 2019 at 6:55 PM Tim McDonough N9PUZ <tim.n9puz@...>
wrote:

We have rolls of material that look similar at work. They cut it to size
for the work area but then the corner gets punched and a snap terminal
installed which has a lead connecting it to ground.

I've been starting to look for a small anti-static mat for my home bench
and these that were mentioned look nice since they have the raised edge
to
help keep things from escaping.

Tim N9PUZ

On 4/14/2019 5:05 PM, AG1P Ron wrote:

I was wondering same thing - From Amazon page -

★This is silicone anti static mat, but its just static resistant, If
you
want ESD protection with your body, you can use it with an anti static
wrist band



72 - Ron - AG1P



*From:* main@4SQRP.groups.io [mailto:main@4SQRP.groups.io
<main@4SQRP.groups.io>] *On Behalf Of *Tim McDonough N9PUZ
*Sent:* Sunday, April 14, 2019 2:54 PM
*To:* main@4SQRP.groups.io
*Subject:* Re: [4SQRP] Anti Static soldering mats



Any idea if these mats are anti-static as well?

Tim N9PUZ

On 4/14/2019 2:02 PM, Virginia R Smith wrote:

Hi Everybody!

It's Virginia NV5F

I met some of you guys at Ozarkcon and had a great time! I hope I can
make it back next year.

During the kit building Joe and I were using these nifty blue silicone
soldering mats. I think there will be something on them in April CQ.

Anyway I was asked to provide information on them here. I actually head
about them from Bob Heil on Ham Nation. Apparently Heil Sound has started
using them. They are used by technicians to repair cell phones and small
electronics but they work great for building kits! They are good for ESD
and aren't affected by hot solder. They also have magnets that will hold
little parts in place until they are needed. The magnets also help the
mat
stick to a cookie sheet!

And I got them on Amazon!

Kaisi S-140 magnetic insulation soldering mat

They come in several sizes. The S-140 fits perfect in a medium steel
cookie sheet from Wal Mart!  And I find that when it gets overrun with
leads and solder blobs you can clean it off with a piece of masking tape.
And if you need to move your work just pick up the cookie sheet. Also the
silicone makes for a nice quiet work surface.

Hope this helps everyone have even more fun building stuff!

Hope to see some of y'all in Dayton.

72
Virginia NV5F






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Wednesday Evening 40 and 80 meter Nets - Wed, 04/17/2019 8:00pm-9:00pm #cal-reminder

main@4SQRP.groups.io Calendar <main@...>
 

Reminder:
Wednesday Evening 40 and 80 meter Nets

When:
Wednesday, 17 April 2019
8:00pm to 9:00pm
(GMT-05:00) America/Chicago

Where:
40 and 80 Meters

Organizer:
jomatlock@...

Description:
The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS will be Bill KV6Z.

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 
The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operators are Johnny AC0BQ or Paul N0NBD.

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.

View Event

Re: Anti Static soldering mats

W4OED
 

Hi there,

I sensed that there was a bit of confusion regarding ESD mats and I would
like to clarify a few things, if I may. BTW, I work at an electronics
equipment factory and I wear an ESD wrist wrap and an ESD lab coat when
writing and verifying the testing procedures for our products.

The Craft E Mat may be good as a work bench protector and components
gathering device, but it is not ESD compliant.

Here you have an example of a true ESD mat:

https://www.amazon.com/Bertech-Temperature-Rubber-Wrist-
Grounding/dp/B01KT3YPPS/ref=sr_1_1_sspa?
crid=WH16OYYVTSYC&keywords=esd+mat+kit+with+a+wrist+strap+and+grounding+cord
&qid=1555363698&s=gateway&sprefix=ESD+mat%2Caps%2C200&sr=8-1-spons&psc=1

In any event, ESD compliant mats and wrist straps are only necessary when
working with ESD sensitive devices, such as MOSFET transistors, computer
ICs, RAM memory sticks, some LEDs (laser and UV), and CMOS ICs. Most TTL
ICs
and bipolar transistors are quite resilient to ESD.

For the most part, when the ESD sensitive devices are soldered or connected
to the PCB, they become more resilient to ESD. When the PCB carrying those
devices is connected to the rest of the equipment, only some I/O ports may
still be ESD sensitive.

ESD compliant mats have a high-resistance top layer that dissipates static
electricity by sending it to a ground connection. This ground can be the
ground terminal of a nearby ac socket or a dedicated low-resistance earth
ground rod. The wrist strap works in a similar fashion.

73!

Original email:
-----------------
From: wohlsson . wohlsson@...
Date: Sun, 14 Apr 2019 21:00:45 -0400
To: main@4sqrp.groups.io
Subject: Re: [4SQRP] Anti Static soldering mats


Opps...forgot the link

https://www.amazon.com/Craft-Mat-Oversize-Worry-
Silicone/dp/B07GBFRCJY/ref=sr_1_1?
keywords=craftemat&qid=1555288975&s=gateway&sr=8-1



Bill...wa8bda

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On Sun, Apr 14, 2019 at 8:58 PM wohlsson . via Groups.Io <wohlsson=
gmail.com@groups.io> wrote:

Yes, these silicone mats are nice for bench work/kit building. I have been
using the one
below now for a few months. Grand kids orginally bought one for craft
projects and I was
attracted to the large 1/2" sides to contain things. Also the large
working area allow me to
also place test equipment/tools on the work area and still have lots of
space. I use a anti-static
wrist band when needed.

Bill.....wa8bda


<https://www.avast.com/sig-email?
utm_medium=email&utm_source=link&utm_campaign=sig-
email&utm_content=webmail&utm_term=icon> Virus-free.
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On Sun, Apr 14, 2019 at 6:55 PM Tim McDonough N9PUZ <tim.n9puz@...>
wrote:

We have rolls of material that look similar at work. They cut it to size
for the work area but then the corner gets punched and a snap terminal
installed which has a lead connecting it to ground.

I've been starting to look for a small anti-static mat for my home bench
and these that were mentioned look nice since they have the raised edge
to
help keep things from escaping.

Tim N9PUZ

On 4/14/2019 5:05 PM, AG1P Ron wrote:

I was wondering same thing - From Amazon page -

★This is silicone anti static mat, but its just static resistant, If
you
want ESD protection with your body, you can use it with an anti static
wrist band



72 - Ron - AG1P



*From:* main@4SQRP.groups.io [mailto:main@4SQRP.groups.io
<main@4SQRP.groups.io>] *On Behalf Of *Tim McDonough N9PUZ
*Sent:* Sunday, April 14, 2019 2:54 PM
*To:* main@4SQRP.groups.io
*Subject:* Re: [4SQRP] Anti Static soldering mats



Any idea if these mats are anti-static as well?

Tim N9PUZ

On 4/14/2019 2:02 PM, Virginia R Smith wrote:

Hi Everybody!

It's Virginia NV5F

I met some of you guys at Ozarkcon and had a great time! I hope I can
make it back next year.

During the kit building Joe and I were using these nifty blue silicone
soldering mats. I think there will be something on them in April CQ.

Anyway I was asked to provide information on them here. I actually head
about them from Bob Heil on Ham Nation. Apparently Heil Sound has started
using them. They are used by technicians to repair cell phones and small
electronics but they work great for building kits! They are good for ESD
and aren't affected by hot solder. They also have magnets that will hold
little parts in place until they are needed. The magnets also help the
mat
stick to a cookie sheet!

And I got them on Amazon!

Kaisi S-140 magnetic insulation soldering mat

They come in several sizes. The S-140 fits perfect in a medium steel
cookie sheet from Wal Mart! And I find that when it gets overrun with
leads and solder blobs you can clean it off with a piece of masking tape.
And if you need to move your work just pick up the cookie sheet. Also the
silicone makes for a nice quiet work surface.

Hope this helps everyone have even more fun building stuff!

Hope to see some of y'all in Dayton.

72
Virginia NV5F




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Re: How do I best operate a 4S-Tuner with a Doublet antenna ?

KB9BVN - <kb9bvn@...>
 

Sounds like a Norcal Doublet....


4S tuner is designed to work best with random wire antennas. 

But I'd try it anyway. 



On Sat, Apr 13, 2019 at 10:23 PM Bob KM6BMX <km6bmx@...> wrote:
Hello, 

  I plan to operate my 4S-Tuner with a 40m "Doublet" antenna.  The doublet has two 1-wire legs, 22 feet each, with a 28 foot 2-wire feedline, which I assume is "balanced". (See URLs below for details). 
 
  I have 2 questions. 
 
    I recently re-read the manual, which states the following:  "With an external balun it will also match antennas with balanced feedlines."  However, there are 2 binding posts that share the same internal circuit connection as the output BNC connector ("ANT"). 
  
  Q1:  Can I just connect the "balanced" 2-wire feedline directly to the posts, picking one as the "antenna" and the other as "ground"? 
  
  On a related note, it seems that the 4S-Tuner is geared primarily towards high-impedance antennas, such as EFHW. 
 
  Q2:  How does it perform with an antenna with an impedance close to the nominal 50 ohms? 
  
  Thanks much for your insights!
 
Cheers & 73,
Bob KM6BMX  
--  central AZ
  
========================================
 
    NorCal "Crappie" antenna 
  
NorCal "Doublet" antenna
 
========================================
 



--
73 de KB9BVN
Brian Murrey

Re: Send in your score

Frank King
 





Sent from my Galaxy Tab E Lite


-------- Original message --------
From: John Lonigro <jonigro@...>
Date: 04/15/2019 6:16 AM (GMT-08:00)
To: 4SQRP@groups.io
Subject: [4SQRP] Send in your score

Re: Send in your score

John Lonigro
 

I guess I need to reiterate that everyone participating in the SSS should think about those with Bayou Jumpers (and other rock-bound rigs) and scan around 7122 (+/- 1 kHz or so) and other 4SQRP frequencies.  Hopefully you'll snare someone like WA9AOE.  Besides getting another couple of points, you'll help your fellow 4SQRPer garner some as well.  Too bad I didn't mention this BEFORE the contest.  I'll try to remind everyone next month.  I think people were more conscious of this shortly after the Bayou Jumper was introduced a few years ago.

By the way, Lee, some of us sign "72" instead of "73" to indicate we are operating QRP.  There's nothing wrong with signing "73" either.

72 (or 73).

John, AA0VE

On 4/15/19 9:37 AM, Leland Lannoye wrote:
I would love to participate. I am OK at abt 12wpm. However, my 7122 xtsl is actually 7121.1. I have a second 7122 xtal that tests out at 7120. I have my Bayou Jumper. I might have my SDR Cube on shortly. It is all controlled but only puts out about 1 watt. X1M is good for 5 watts but the receiver is noisy.

72(?), 
Lee, WA9AOE 




Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: Paul Smith <n0nbd@...>
Date: 4/15/19 10:11 (GMT-05:00)
Subject: Re: [4SQRP] Send in your score

I backed into the Sprint.
I responded to Terry's post and found 3 guys on 7122 and then found Terry on 3564... The QSB was fast but I got em. de Paul N0NBD

Sent from Outlook


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of John Lonigro <jonigro@...>
Sent: Monday, April 15, 2019 1:16 PM
To: 4SQRP@groups.io
Subject: [4SQRP] Send in your score
 
This is a friendly reminder to enter your Second Sunday Sprint scores by
tonight.  Go to qrpcontest.com/4sqrp to do so.  I will tabulate the
results tomorrow and publish them by Wednesday morning.

72,

John, AA0VE
4SQRP Contest Coordinator




Re: Send in your score

Leland Lannoye
 

I would love to participate. I am OK at abt 12wpm. However, my 7122 xtsl is actually 7121.1. I have a second 7122 xtal that tests out at 7120. I have my Bayou Jumper. I might have my SDR Cube on shortly. It is all controlled but only puts out about 1 watt. X1M is good for 5 watts but the receiver is noisy.

72(?), 
Lee, WA9AOE 




Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: Paul Smith <n0nbd@...>
Date: 4/15/19 10:11 (GMT-05:00)
To: main@4SQRP.groups.io
Subject: Re: [4SQRP] Send in your score

I backed into the Sprint.
I responded to Terry's post and found 3 guys on 7122 and then found Terry on 3564... The QSB was fast but I got em. de Paul N0NBD

Sent from Outlook


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of John Lonigro <jonigro@...>
Sent: Monday, April 15, 2019 1:16 PM
To: 4SQRP@groups.io
Subject: [4SQRP] Send in your score
 
This is a friendly reminder to enter your Second Sunday Sprint scores by
tonight.  Go to qrpcontest.com/4sqrp to do so.  I will tabulate the
results tomorrow and publish them by Wednesday morning.

72,

John, AA0VE
4SQRP Contest Coordinator



Re: Send in your score

Paul Smith
 

I backed into the Sprint.
I responded to Terry's post and found 3 guys on 7122 and then found Terry on 3564... The QSB was fast but I got em. de Paul N0NBD

Sent from Outlook


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of John Lonigro <jonigro@...>
Sent: Monday, April 15, 2019 1:16 PM
To: 4SQRP@groups.io
Subject: [4SQRP] Send in your score
 
This is a friendly reminder to enter your Second Sunday Sprint scores by
tonight.  Go to qrpcontest.com/4sqrp to do so.  I will tabulate the
results tomorrow and publish them by Wednesday morning.

72,

John, AA0VE
4SQRP Contest Coordinator



Send in your score

John Lonigro
 

This is a friendly reminder to enter your Second Sunday Sprint scores by tonight.  Go to qrpcontest.com/4sqrp to do so.  I will tabulate the results tomorrow and publish them by Wednesday morning.

72,

John, AA0VE
4SQRP Contest Coordinator