sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

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Today's topics:

* Arfa Daily = Pommy Cunt - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/1e12bfd4ba9ca5dd?hl=en
* Why would a DECT Panasonic cordless phone keep losing the wireless link? - 3
messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/cc34e585e15dfff5?hl=en
* Unsolderable wire? - 21 messages, 16 authors
http://groups.google.com/group/sci.electronics.repair/t/846b59baa6a8b7e9?hl=en

==============================================================================
TOPIC: Arfa Daily = Pommy Cunt
http://groups.google.com/group/sci.electronics.repair/t/1e12bfd4ba9ca5dd?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Jan 18 2014 12:41 pm
From: "Gareth Magennis"



I have had a few alarm bells from Farnell recently.

Here's one - I had an old Lexicon 224 reverb to repair that had a problem
with the crowbar circuitry on the 5v line.
It used a 6vsomething Zener and a Triac to short out said line should it
rise above 6vsomethingelse volts.
Which it was doing on an extremely intermittent basis. Hard to determine if
the problem was the supply or the protection.


Anyway, after days of testing and discovering it was the protection, I
ordered the appropriate 6vsomthing zeners from Farnell.

Fortunately for me, I decided to construct a quick test rig just to make
sure the new Zener and Triac did indeed go short at the required
overvoltage.

Well it didn't.


It turned out these 6vsomething zeners were nothing of the sort. I couldn't
make them breakdown with my bench supply at 30v. It was not possible to
tell from the markings what they were.

I got these replaced with proper Zeners, and then the rig tripped out at the
less than 7 volts it was supposed to do.


Had I just fitted this zener without checking it was what it said it was,
the 224 would have been vulnerable to the 5v line going hugely overvoltage
and taking out every single digital IC in the unit. (100's of them)


This is, in fact, the VERY reason I chose to try and test the TIP35C
transistors before installing them in the Power Amp.



With regards me testing these TIP's with my dodgy tester, I may well be
wrong about them being dodgy, I understand fully what Phil has been saying,
and it is entirely possible he has been correct all along. Thing is I
reacted to the way he was reacting, maybe that wasn't the smartest thing to
do, I can normally tolerate him a lot better.
I apologise for that, Phil, it shouldn't really have gone that way.

I stated from the very outset that I knew a Hfe reading from this tester on
a Power Transistor was "meaningless", but this seems to have been largely
ignored.
In fact the reason I knew of this was because of previous posts by Phil
probably a couple of years ago now on this thread.

Thing is though, all 4 replacements read OK at a healthy Hfe of 60 - 70,
where all 4 of the other batch read pretty much zero, most probably because
of a confused pinout diagnosis from the tester, or maybe because they really
are dodgy at the lower extremities of operation, where they would not be
operated anyway.

I did later construct a quick test rig on 2 of these old "dodgy" TIP35C's
which showed, at around 0.5A collector current, an Hfe of around 49, and the
correct pinout.
I suspect the other 2 will be similar, but I will not be putting any of
these into a Power Amp.
At less than �1 each I think Farnell can afford another 4 my dodgy old
tester doesn't have a problem with.



Cheers,


Gareth.











== 2 of 2 ==
Date: Sat, Jan 18 2014 6:08 pm
From: "Phil Allison"



"Gareth Magennis"

>
> With regards me testing these TIP's with my dodgy tester, I may well be
> wrong about them being dodgy, I understand fully what Phil has been
> saying, and it is entirely possible he has been correct all along. Thing
> is I reacted to the way he was reacting, maybe that wasn't the smartest
> thing to do, I can normally tolerate him a lot better.
> I apologise for that, Phil, it shouldn't really have gone that way.


** OK.

> I stated from the very outset that I knew a Hfe reading from this tester
> on a Power Transistor was "meaningless", but this seems to have been
> largely ignored.

** As I explained repeatedly, the Peak meter uses Hfe readings to determine
C and E.

So if it *cannot read Hfe reliably* for a particular BJT - then it CANNOT
always get C and E right.

There is no magic way to determine C and E with certainty other than break
down voltage tests ( the CE junction should go at about 12V while the CB
one ought to be higher) - with only an internal 5V supply, the Peak tester
cannot do this test.



> In fact the reason I knew of this was because of previous posts by Phil
> probably a couple of years ago now on this thread.
>
> Thing is though, all 4 replacements read OK at a healthy Hfe of 60 - 70,
> where all 4 of the other batch read pretty much zero, most probably
> because of a confused pinout diagnosis from the tester, or maybe because
> they really are dodgy at the lower extremities of operation, where they
> would not be operated anyway.
>
> I did later construct a quick test rig on 2 of these old "dodgy" TIP35C's
> which showed, at around 0.5A collector current, an Hfe of around 49, and
> the correct pinout.


** Halleluiah.


.... Phil









==============================================================================
TOPIC: Why would a DECT Panasonic cordless phone keep losing the wireless link?

http://groups.google.com/group/sci.electronics.repair/t/cc34e585e15dfff5?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Jan 18 2014 6:46 pm
From: Danny D'Amico


On Tue, 14 Jan 2014 23:57:25 -0500, Tony Matt wrote:

> These/some Panasonic
> cordless handsets display a "Charge for 7 hours" message (and a single
> bar on the battery gauge) whenever batteries are installed, regardless
> of the state-of-charge.

Thanks for confirming.

It took me a while (mostly at Jeff's insistance) to test the batteries,
which, turned out (surprisingly) to be fine, even though the phone
said they needed charging, right after the phone said they were fine.

Go figure.
SO far, it has worked out ok, so, I think the re-registration process
was what fixed it (I think).





== 2 of 3 ==
Date: Sat, Jan 18 2014 6:50 pm
From: Danny D'Amico


On Tue, 14 Jan 2014 22:04:18 -0700, Tony Hwang wrote:

> Maybe I am dumb or simple minded. Manual says charge 7 hours B4 using. I
> just left it over night out of box. Ever since they all have been
> reliably working. At home and at the store.

My experiments pretty much proved that the following would happen:
a) Leave batteries in overnight - handset display says they're full.
b) Pull batteries out momentarily & put them back in
c) Now handset display says (the same batteries) need 7 hours of charging

So, I'm going with the recommendation to ignore whatever the handset
display says if you've just put in batteries.





== 3 of 3 ==
Date: Sat, Jan 18 2014 8:33 pm
From: Tony Hwang


Danny D'Amico wrote:
> On Tue, 14 Jan 2014 23:57:25 -0500, Tony Matt wrote:
>
>> These/some Panasonic
>> cordless handsets display a "Charge for 7 hours" message (and a single
>> bar on the battery gauge) whenever batteries are installed, regardless
>> of the state-of-charge.
>
> Thanks for confirming.
>
> It took me a while (mostly at Jeff's insistance) to test the batteries,
> which, turned out (surprisingly) to be fine, even though the phone
> said they needed charging, right after the phone said they were fine.
>
> Go figure.
> SO far, it has worked out ok, so, I think the re-registration process
> was what fixed it (I think).
>
Hmmm,
Panasonic implemented mandatory >7 hour initial charge to ensure long
battery life. On any rechargeable batteries proper initial charge is
very important. It is not whether battery is charged or not. It is just
so. You are obliged to make sure at least 7 hour charging time. Usually
owners manual does not explain things in full. Panasonic CL phones in
my house is almost 10 years old. None yet needs new battery.





==============================================================================
TOPIC: Unsolderable wire?
http://groups.google.com/group/sci.electronics.repair/t/846b59baa6a8b7e9?hl=en
==============================================================================

== 1 of 21 ==
Date: Sat, Jan 18 2014 8:22 pm
From: Bob E.


I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
almost like it's dissipating the heat faster than I can apply it. With both a
temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
tried. The solder will barely melt when touched to the braid opposite the
iron.

I've applied some Kester rosin paste flux as well using my trusty Kester
60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
the PCB now, I'm just trying to tin the braid and then deal with melting the
2 solders (on the PCB and the braid) together later.

My first attempt--before I realized that I was overheating it--I melted the
dielectric insulation.

The mesh is made from some silver-colored braid which I thought is tinned
copper but now I'm of the opinion that it's steel; it's certainly not
aluminum. There is also foil which is probably aluminum but I've trimmed that
back and it's not part of this frustrating process right now.

What's the trick to getting this braid to take solder? I've never seen this
before.

Thanks.





== 2 of 21 ==
Date: Sat, Jan 18 2014 8:37 pm
From: Spehro Pefhany


On Sat, 18 Jan 2014 20:22:18 -0800, the renowned Bob E.
<bespoke@invalid.tv> wrote:

>I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
>almost like it's dissipating the heat faster than I can apply it. With both a
>temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
>tried. The solder will barely melt when touched to the braid opposite the
>iron.
>
>I've applied some Kester rosin paste flux as well using my trusty Kester
>60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
>the PCB now, I'm just trying to tin the braid and then deal with melting the
>2 solders (on the PCB and the braid) together later.
>
>My first attempt--before I realized that I was overheating it--I melted the
>dielectric insulation.
>
>The mesh is made from some silver-colored braid which I thought is tinned
>copper but now I'm of the opinion that it's steel; it's certainly not
>aluminum. There is also foil which is probably aluminum but I've trimmed that
>back and it's not part of this frustrating process right now.
>
>What's the trick to getting this braid to take solder? I've never seen this
>before.
>
>Thanks.

If it's like this cr*p they sell at Home Despot, it's copper clad
steel core with an _aluminum_ braid shield:-

http://www.cerrowire.com/files/file/49223_CERRO_CoaxialCable_6U_QUADLR.pdf

That would explain the copper-like heat conduction that you're
observing.

I suppose you could try an aluminum flux, but can't you just unravel
and gather enough of the shield to crimp into a ring terminal or
something?



Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com




== 3 of 21 ==
Date: Sat, Jan 18 2014 8:40 pm
From: "Michael A. Terrell"



"Bob E." wrote:
>
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
> tried. The solder will barely melt when touched to the braid opposite the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
> the PCB now, I'm just trying to tin the braid and then deal with melting the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen this
> before.

It's not made to be soldered. It's CATV cable that's made for crimp
on 'F' fittings.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.




== 4 of 21 ==
Date: Sat, Jan 18 2014 8:42 pm
From: "Phil Allison"



"Bob E."

>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum.

** A magnet will pick up steel wire - but no Aluminium.


> What's the trick to getting this braid to take solder?


** Unplated steel or Aluminium wires are not solderable by ordinary means.




.... Phil






== 5 of 21 ==
Date: Sat, Jan 18 2014 8:43 pm
From: Tom Biasi


On 1/18/2014 11:22 PM, Bob E. wrote:
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
> tried. The solder will barely melt when touched to the braid opposite the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
> the PCB now, I'm just trying to tin the braid and then deal with melting the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen this
> before.
>
> Thanks.
>
Twist the braid into a wire and butt splice on a copper wire. Heat
shrink over it.




== 6 of 21 ==
Date: Sat, Jan 18 2014 8:50 pm
From: Bob E.


Yes it's that crap.

> I suppose you could try an aluminum flux, but can't you just unravel
> and gather enough of the shield to crimp into a ring terminal or
> something?

Yeah, that's my next move. I just couldn't believe that something couldn't be
soldered. I guess REALLY agressive flux is required, as you say.

When it comes to broadcast TV I try to solder every connection possible.
Every crimp is one more dB lost.

Thanks.

Crimps in hand...





== 7 of 21 ==
Date: Sat, Jan 18 2014 9:09 pm
From: Spehro Pefhany


On Sat, 18 Jan 2014 20:50:34 -0800, the renowned Bob E.
<bespoke@invalid.tv> wrote:

>Yes it's that crap.
>
>> I suppose you could try an aluminum flux, but can't you just unravel
>> and gather enough of the shield to crimp into a ring terminal or
>> something?
>
>Yeah, that's my next move. I just couldn't believe that something couldn't be
>soldered. I guess REALLY agressive flux is required, as you say.
>
>When it comes to broadcast TV I try to solder every connection possible.
>Every crimp is one more dB lost.
>
>Thanks.
>
>Crimps in hand...

I guess there's always better stuff like this:-

http://nordencommunication.com/download?file=1460-RG_6u.pdf



Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com




== 8 of 21 ==
Date: Sat, Jan 18 2014 10:19 pm
From: "Michael A. Terrell"



"Bob E." wrote:
>
> Yes it's that crap.
>
> > I suppose you could try an aluminum flux, but can't you just unravel
> > and gather enough of the shield to crimp into a ring terminal or
> > something?
>
> Yeah, that's my next move. I just couldn't believe that something couldn't be
> soldered. I guess REALLY agressive flux is required, as you say.
>
> When it comes to broadcast TV I try to solder every connection possible.
> Every crimp is one more dB lost.


You must do lousy crimping, if you lose a dB.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.




== 9 of 21 ==
Date: Sat, Jan 18 2014 10:41 pm
From: cjt


On 01/18/2014 10:50 PM, Bob E. wrote:
> Yes it's that crap.
>
>> I suppose you could try an aluminum flux, but can't you just unravel
>> and gather enough of the shield to crimp into a ring terminal or
>> something?
>
> Yeah, that's my next move. I just couldn't believe that something couldn't be
> soldered. I guess REALLY agressive flux is required, as you say.
>
> When it comes to broadcast TV I try to solder every connection possible.
> Every crimp is one more dB lost.
>
> Thanks.
>
> Crimps in hand...
>
I would have thought every soldered joint is one more reflection.




== 10 of 21 ==
Date: Sat, Jan 18 2014 11:16 pm
From: Bob E.


>> When it comes to broadcast TV I try to solder every connection possible.
>> Every crimp is one more dB lost.

I'm no RF expert, just my impression--possibly mistaken.

Thanks.





== 11 of 21 ==
Date: Sat, Jan 18 2014 11:30 pm
From: "Michael A. Terrell"



"Bob E." wrote:
>
> >> When it comes to broadcast TV I try to solder every connection possible.
> >> Every crimp is one more dB lost.
>
> I'm no RF expert, just my impression--possibly mistaken.


The loss should be under .1 dB for a good F connector, ant they are
used into the GHz range.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.




== 12 of 21 ==
Date: Sun, Jan 19 2014 1:13 am
From: John Fields


On Sat, 18 Jan 2014 20:22:18 -0800, Bob E. <bespoke@invalid.tv>
wrote:

>I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
>almost like it's dissipating the heat faster than I can apply it. With both a
>temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
>tried. The solder will barely melt when touched to the braid opposite the
>iron.
>
>I've applied some Kester rosin paste flux as well using my trusty Kester
>60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
>the PCB now, I'm just trying to tin the braid and then deal with melting the
>2 solders (on the PCB and the braid) together later.
>
>My first attempt--before I realized that I was overheating it--I melted the
>dielectric insulation.
>
>The mesh is made from some silver-colored braid which I thought is tinned
>copper but now I'm of the opinion that it's steel; it's certainly not
>aluminum. There is also foil which is probably aluminum but I've trimmed that
>back and it's not part of this frustrating process right now.
>
>What's the trick to getting this braid to take solder? I've never seen this
>before.
>
>Thanks.

---
Use crimp ferrules.

http://www.te.com/catalog/feat/en/c/10028

11.5 at:

http://snebulos.mit.edu/projects/reference/NASA-Generic/NASA-STD-8739-4.pdf

JF




== 13 of 21 ==
Date: Sun, Jan 19 2014 2:34 am
From: Jasen Betts


On 2014-01-19, Bob E <bespoke@invalid.tv> wrote:
> I am trying to solder some RG-6 shield to a pcb.

> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.

yeah stainless steel braid, aluminium shield and a copper-plated steel
core. most of the RG6 I've used is like that.

a solderable F connector socket is probably the best way to terminate it.

> What's the trick to getting this braid to take solder?

Give up! If you can't give up spot weld it to some tinned copper.

--
For a good time: install ntp

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---




== 14 of 21 ==
Date: Sun, Jan 19 2014 4:19 am
From: Syd Rumpo


On 19/01/2014 04:22, Bob E. wrote:
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
> tried. The solder will barely melt when touched to the braid opposite the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
> the PCB now, I'm just trying to tin the braid and then deal with melting the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen this
> before.
>
> Thanks.

If it's for personal use, tightly wrap a dozen turns of tinned copper
wire (or silver plated) around the braid, twist the end together and
solder to these.

Cheers
--
Syd




== 15 of 21 ==
Date: Sun, Jan 19 2014 5:45 am
From: "William Sommerwerck"


"Spehro Pefhany" wrote in message
news:v8lmd9tfpopj1kuv72m95aouolvlduj539@4ax.com...

> If it's like this cr*p they sell at Home Despot, it's copper-
> clad steel core with an _aluminum_ braid shield.

Aluminum is a poor choice for a crimped connection. Remember the problems with
household aluminum wiring -- even when it was screwed down?





== 16 of 21 ==
Date: Sun, Jan 19 2014 6:04 am
From: "Maynard A. Philbrook Jr."


In article <0001HW.CF0092FA036D6B77B01029BF@news.eternal-september.org>,
bespoke@invalid.tv says...
>
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
> tried. The solder will barely melt when touched to the braid opposite the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
> the PCB now, I'm just trying to tin the braid and then deal with melting the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen this
> before.
>
> Thanks.

Electroplated wire, most likely nickel.

Jamie





== 17 of 21 ==
Date: Sun, Jan 19 2014 6:38 am
From: "Tim Williams"


Well, what does it feel like?

Steel wire feels very stiff. Grab a leaded component out of the box and
ponder the leads; they're probably tin plated steel (check with a magnet).
Most resistors, capacitors and diodes are. Some smaller ceramic caps have
thicker, softer copper leads; find some if you can.

Aluminum wire is very soft, floppy stuff. It is much softer than copper,
than copper is of steel. If that's what it is... oh well.

As for soldering practice... the old saw about "apply solder to the
opposite side of the joint" is complete BS. Forget about it. Don't try
soldering as you were told, make the solder happy and good joints will
follow. First goal, get the part hot: hold the iron on the part, and
apply solder right beside the iron, or to it, so the iron heats and wets
what it's touching. On a braid, solder will spread and soon the joint
will accept solder from all sides.

Tim

--
Seven Transistor Labs
Electrical Engineering Consultation
Website: http://seventransistorlabs.com

"Bob E." <bespoke@invalid.tv> wrote in message
news:0001HW.CF0092FA036D6B77B01029BF@news.eternal-september.org...
>I am trying to solder some RG-6 shield to a pcb. The braid won't tin.
>It's
> almost like it's dissipating the heat faster than I can apply it. With
> both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I
> finally
> tried. The solder will barely melt when touched to the braid opposite
> the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid
> against
> the PCB now, I'm just trying to tin the braid and then deal with melting
> the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted
> the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is
> tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed
> that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen
> this
> before.
>
> Thanks.
>






== 18 of 21 ==
Date: Sun, Jan 19 2014 7:45 am
From: dave


On 01/18/2014 08:22 PM, Bob E. wrote:
> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With both a
> temp-controlled iron (set as high as 700F) and a mondo 100W stick I finally
> tried. The solder will barely melt when touched to the braid opposite the
> iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid against
> the PCB now, I'm just trying to tin the braid and then deal with melting the
> 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted the
> dielectric insulation.
>
> The mesh is made from some silver-colored braid which I thought is tinned
> copper but now I'm of the opinion that it's steel; it's certainly not
> aluminum. There is also foil which is probably aluminum but I've trimmed that
> back and it's not part of this frustrating process right now.
>
> What's the trick to getting this braid to take solder? I've never seen this
> before.
>
> Thanks.
>

A solder pot is preferred. Otherwise burn all the non-metallic weirdness
away with your trusty Zippo.




== 19 of 21 ==
Date: Sun, Jan 19 2014 7:49 am
From: Baron


Michael A. Terrell scribbled thus:

>
> "Bob E." wrote:
>>
>> Yes it's that crap.
>>
>> > I suppose you could try an aluminum flux, but can't you just
>> > unravel and gather enough of the shield to crimp into a ring
>> > terminal or something?
>>
>> Yeah, that's my next move. I just couldn't believe that something
>> couldn't be soldered. I guess REALLY agressive flux is required, as
>> you say.
>>
>> When it comes to broadcast TV I try to solder every connection
>> possible. Every crimp is one more dB lost.
>
>
> You must do lousy crimping, if you lose a dB.
>

I agree ! A good crimp is at least as good as the best solder joint.

--
Best Regards:
Baron.




== 20 of 21 ==
Date: Sun, Jan 19 2014 9:09 am
From: Fred Abse


On Sat, 18 Jan 2014 20:22:18 -0800, Bob E. wrote:

> I am trying to solder some RG-6 shield to a pcb. The braid won't tin. It's
> almost like it's dissipating the heat faster than I can apply it. With
> both a temp-controlled iron (set as high as 700F) and a mondo 100W stick I
> finally tried. The solder will barely melt when touched to the braid
> opposite the iron.
>
> I've applied some Kester rosin paste flux as well using my trusty Kester
> 60/40 lead-based rosin core solder. No joy. I'm not holding the braid
> against the PCB now, I'm just trying to tin the braid and then deal with
> melting the 2 solders (on the PCB and the braid) together later.
>
> My first attempt--before I realized that I was overheating it--I melted
> the dielectric insulation.

Its virtually impossible to tin polyethylene coax braid without softening
the dielectric. It will re-solidify. PTFE (Teflon) is better in that
respect.

>
> The mesh is made from some silver-colored braid which I thought is
> tinned copper but now I'm of the opinion that it's steel; it's certainly
> not aluminum. There is also foil which is probably aluminum but I've
> trimmed that back and it's not part of this frustrating process right
> now.

If you think the braid is steel, try it with a magnet.

From a quick look at Belden specs, they, at least, don't make any RG6
types with steel braid. There are some versions with aluminum braid.

>
> What's the trick to getting this braid to take solder? I've never seen
> this before.
>

If it's aluminum, you can't. Either get some cable with tinned or silver
plated copper braid, or put a BNC socket on the PCB, and a crimp BNC on
the cable. (I don't trust crimping to aluminum, BTW, there's a
metallurgical creep problem)

--
"Design is the reverse of analysis"
(R.D. Middlebrook)




== 21 of 21 ==
Date: Sun, Jan 19 2014 11:57 am
From: Phil Hobbs


On 1/19/2014 2:30 AM, Michael A. Terrell wrote:
>
> "Bob E." wrote:
>>
>>>> When it comes to broadcast TV I try to solder every connection possible.
>>>> Every crimp is one more dB lost.
>>
>> I'm no RF expert, just my impression--possibly mistaken.
>
>
> The loss should be under .1 dB for a good F connector,
^^^^^^^^^^^^^^^^
Jumbo shrimp alert. ;)

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net




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