Date   

Re: Smokey

Ted 2E0THH
 

On Wed, Jan 27, 2021 at 03:30 PM, James Daldry W4JED wrote:
Hi, Guys

Radio station WWHG in Hornell, New York at one time (maybe still does) had station monitor audio wired to standard 120 volt type duplex outlets. They also had a number of interesting smelling studio monitor speakers with torn grille cloth.
HiHI brilliant!
73s Ted


Re: Smokey

James Daldry W4JED
 

On 2021-01-27 08:35, Mike Besemer - WM4B wrote:
What connector are you talking about?
None of my QRP labs products has an audio connector for a DC power
plug.
Mike
WM4B
On Jan 27, 2021, at 9:22 AM, kf4pv@... wrote:

Ted,
I agree. I like these rigs enough that I have 2 of them and will buy
more stuff here. But that doesn't change the fact that using an
audio connector as a power connector is not good practice.
I am not attacking anyone nor calling the rig junk, only pointing
out:
1. That this is not a user/operator error (which may be some small
comfort to the owners of smoked rigs).
2. Why it's a design error that should be fixed with an eventual
board rev
3. There are ways for builders to fix this until the kit is
changed
This may be a hobby, but it's also a business. All the builders have
paid money for these kits and assembled products, so having them
self-destruct, even if only occasionally, is a problem. The last
thing we need is for QRP Labs to get a bad reputation and go bust,
or to have to spend all their time and money replacing burned out
boards and go bust. That would be end of the fun toys for us. It was
in that spirit that I was pointing out the issues so that they can
be fixed. That included justifications beyond just "this sucks" so
that the design flaw could be properly recognized as such and my
comments taken seriously.
The other thing about it being a hobby, is that many of the builders
are not professional EE's, RF engineers, etc. They use these
accessible and well-documented designs as inspirations and examples.
For many this is the start of their career path. Because of that,
it'd be good if bad habits, such as using audio connectors to carry
power, were nipped in the bud.
So that's why I posted my comments. I've seen a lot of bad design
decisions over the decades, including the ones I made myself. It's
just part of the design process. This particular one, the
inappropriate use of connector types, is very common, especially in
small outfits that don't use the same design/review processes that
the large companies use. There will always be errors, the trick is
when you catch them. Following standards lets you avoid the errors
escaping into the wild.
73
Laszlo
_._,_._,_
-------------------------
Groups.io Links:
You receive all messages sent to this group.
View/Reply Online (#61947) [1] | Reply To Group | Reply To Sender |
Mute This Topic [2] | New Topic [3]
Hi, Guys

Radio station WWHG in Hornell, New York at one time (maybe still does) had station monitor audio wired to standard 120 volt type duplex outlets. They also had a number of interesting smelling studio monitor speakers with torn grille cloth.

73
Jim W4JED


Re: Smokey

Mike Besemer - WM4B
 

Dan,

Some people would complain if they are hung with a new rope

Mike
WM4B

On Jan 27, 2021, at 9:56 AM, Daniel Conklin <danconklin2@...> wrote:
It's pretty common to use an audio connector to carry power. In audio equipment it's called "Phantom Power" and is normally a much higher voltage.
--
73, Dan - W2DLC


Re: Smokey

Mike Besemer - WM4B
 

That is not a power connector. It is an interface. There is a difference. If you look at any number of commercially available amateur radio gear you'll find these very same connectors being used as interfaces.

The problem lies in a poor regulator design that causes it to commit suicide with little provocation. To make matters worse common the failure mode of said regulator is the worst possible scenario. Supposedly the 1117s made by TI do not fail shorted, but I don't know that I would bank on it.

The 78M05  should be an easy replacement for the 1117. If you install the 78M05 shifted one pin to the left so the input ties to the diode, it is a pin for pin replacement.  Mine will be done as  soon as the parts arrive from Mouser.

All this being said, it's poor practice to hot plug any interface on any device.  Those of us who cut our teeth working around high voltages can attest to what can happen to an individual when they choose to hot plug.  Measure twice - cut once.

Mike
WM4B

On Jan 27, 2021, at 9:51 AM, kf4pv@... wrote:
PTT on the QCX series. It carries PTT, +5v and ground on a 3.5 mm stereo connector.


Re: Smokey

Daniel Conklin
 

It's pretty common to use an audio connector to carry power. In audio equipment it's called "Phantom Power" and is normally a much higher voltage.
--
73, Dan - W2DLC


Re: Smokey

kf4pv@...
 

PTT on the QCX series. It carries PTT, +5v and ground on a 3.5 mm stereo connector.


Re: Smokey

Mike Besemer - WM4B
 

What connector are you talking about?

None of my QRP labs products has an audio connector for a DC power plug.

Mike
WM4B

On Jan 27, 2021, at 9:22 AM, kf4pv@... wrote:
Ted,

I agree. I like these rigs enough that I have 2 of them and will buy more stuff here. But that doesn't change the fact that using an audio connector as a power connector is not good practice.

I am not attacking anyone nor calling the rig junk, only pointing out:
  1. That this is not a user/operator error (which may be some small comfort to the owners of smoked rigs).
  2. Why it's a design error that should be fixed with an eventual board rev
  3. There are ways for builders to fix this until the kit is changed

This may be a hobby, but it's also a business. All the builders have paid money for these kits and assembled products, so having them self-destruct, even if only occasionally, is a problem. The last thing we need is for QRP Labs to get a bad reputation and go bust, or to have to spend all their time and money replacing burned out boards and go bust. That would be end of the fun toys for us. It was in that spirit that I was pointing out the issues so that they can be fixed. That included justifications beyond just "this sucks" so that the design flaw could be properly recognized as such and my comments taken seriously.

The other thing about it being a hobby, is that many of the builders are not professional EE's, RF engineers, etc. They use these accessible and well-documented designs as inspirations and examples. For many this is the start of their career path. Because of that, it'd be good if bad habits, such as using audio connectors to carry power, were nipped in the bud.

So that's why I posted my comments. I've seen a lot of bad design decisions over the decades, including the ones I made myself. It's just part of the design process. This particular one, the inappropriate use of connector types, is very common, especially in small outfits that don't use the same design/review processes that the large companies use. There will always be errors, the trick is when you catch them. Following standards lets you avoid the errors escaping into the wild.

73
Laszlo


Re: QCX+ no reception #40m

howard winwood G4GPF
 

So! enamelled copper wire, unfortunately there are two types (generally) of insulation, usually a varnish coating.
On one type the enamelling can be burned off either with a hotter than usual soldering iron, you will need a temp controlled iron that you can vary the temp.
Get a blob of solder on the end of the iron and pass the enamelled wire into the solder and leave it there for a few seconds (10-20 usually sufficient), moving the wire in and out of the solder, until you see
that the wire is now tinned with solder.
The other type of wire will have a coating that WILL NOT BURN off.
If you do not have a variable temp iron you will have to use method 2, which is to either use a small piece of fine sandpaper to run on the wire until the enamel is removed, then tin the area where you have removed the enamel.
If the solder does not take, use the sandpaper again. Another option is to use a sharp craft knife or pen knife to GENTLY scrape the enamel off the wire.
The danger with this method is that you may nick the wire making it susceptible to breaking if you bend it too often.

The method I would recommend is to put all the wires from the toroid through the holes in the circuit board, pull the wires tight, then cut the wire about 10mm or 1/2 inch from the circuit board.
Prepare the wire ends for 10mm or 1/2 inch using one of the above methods and make sure ALL the leads are tinned, it should be obvious by the silver colour of the tinning.
Replace the toroid on the circuit board and solder the now tinned wires and cut off the excess wire. Inspecting closely you should see a classic solder joint.
If you do not know what one is Google it so you know what to look for.
Trying to spot a dry joint is NOT always obvious, good preparation is the key to good solder joints.
This is why so many, my self included, suggest you tackle something easier to start with, so you can recognise a good solder joint.
It is not difficult BUT there are traps for the unwary.
And, No! I am not immune to bad joints (solder not anatomical), you just have to be aware and inspect closely.

Good building guys and gals

On 27 Jan 2021, at 12:26, M0JHS <graham@...> wrote:

Thank you Dan, I did kick myself when I spotted my soldering mistake!

That's just it, I'm fairly newly qualified as you might guess by my call sign.
QCX+ is the first proper radio kit I've built (I've designed and built other microprocessor stuff in the past), uBitx is pretty much assembled.
I looked on here for an FAQ or previous posts that went further than Hans' excellent manual, but drew a blank, hence my question.

So, if bad soldering of enamelled wires is a problem, the big question is how you go about addressing this?
Clearly a long post pointing out the lack of experience of those new (M6, M7s) hasn't solved it, neither is this post as it soon gets buried.

When I'm next soldering enamelled wire I'm going to deliberately make a poor solder joint, photograph it and make a file/post to show the difference between a poor and well made enamelled Cu wire join. Not sure how to make the file/post sticky but a resource like this would go a long way to a) helping other (new) amateurs b) reduce the amount of questions like I posted c) reduce the exasperation of more experienced amateurs replying to newbie questions.

Thank you to all who offered advice and helped my learning.
73
Graham
M0JHS


Re: QCX+ no reception #40m

N3MNT
 

I have built 7 QRP-Labs kits and I always use an Exacto knife to scrape off the enamel by running between my finger and the blade.


Re: Smokey

kf4pv@...
 

Ted,

I agree. I like these rigs enough that I have 2 of them and will buy more stuff here. But that doesn't change the fact that using an audio connector as a power connector is not good practice.

I am not attacking anyone nor calling the rig junk, only pointing out:
  1. That this is not a user/operator error (which may be some small comfort to the owners of smoked rigs).
  2. Why it's a design error that should be fixed with an eventual board rev
  3. There are ways for builders to fix this until the kit is changed

This may be a hobby, but it's also a business. All the builders have paid money for these kits and assembled products, so having them self-destruct, even if only occasionally, is a problem. The last thing we need is for QRP Labs to get a bad reputation and go bust, or to have to spend all their time and money replacing burned out boards and go bust. That would be end of the fun toys for us. It was in that spirit that I was pointing out the issues so that they can be fixed. That included justifications beyond just "this sucks" so that the design flaw could be properly recognized as such and my comments taken seriously.

The other thing about it being a hobby, is that many of the builders are not professional EE's, RF engineers, etc. They use these accessible and well-documented designs as inspirations and examples. For many this is the start of their career path. Because of that, it'd be good if bad habits, such as using audio connectors to carry power, were nipped in the bud.

So that's why I posted my comments. I've seen a lot of bad design decisions over the decades, including the ones I made myself. It's just part of the design process. This particular one, the inappropriate use of connector types, is very common, especially in small outfits that don't use the same design/review processes that the large companies use. There will always be errors, the trick is when you catch them. Following standards lets you avoid the errors escaping into the wild.

73
Laszlo


Re: QCX mini 20M no output, can't adjust IQ,lo and hi. #qcx20mini #qcxmini #alignment

Khor Lai Hock
 

If is all ok, why i can't adjust IQ balance, Hi and lo also.
my power output also low, less than 1w.
where i should look for?

De 9M2KLH


Re: QCX+ no reception #40m

va3rr
 

For larger diameter wire, I scrape and sand off the enamel.
And I remove enough enamel so I get a good solder joint on both sides of the thru-hole via...

On Wed, Jan 27, 2021 at 08:56 AM, Chuck - K3FLN wrote:
Graham,
I know Hans likes this method, but if you try this you will never go back...


Re: Smokey

Fend Ercin
 

I have to agree with Ted. If one wants all the features Laszlo mentions, one can always type Yaesu or ICOM instead of QRPLabs on the browser. This is a hobby.

73s Felipe


Re: Smokey

N3MNT
 

I have to disagree.  QRP-Labs designs AMATEUR radio kits with amazing performance at very reasonable prices.  In particular, the mini was a requested reconfiguration of the QCX for minimum size as was accomplished in record time.  Trade-offs were made to accomplish this but as AMATEURS we should be able to understand and accommodate them.   The mini does not have  protection against transmitting into a shorted or open antenna but that does not render it less usable.  If someone needs a fool proof radio there are options like the Elecraft KX2 for $900.


On Wed, Jan 27, 2021 at 08:03 AM, <kf4pv@...> wrote:
At the risk of offending someone (which I'm really not trying to do) this is a design error on multiple levels. Stereo plugs are not designed to be power connectors and it was misguided to use them as such. There is also an accepted standard for hot plugging stereo connectors that doing so will not destroy the equipment. This design violates both standards.

Power connectors are designed to prevent short circuits. They are polarized and use separate pins for each voltage and ground. The stereo plug does not fit this requirement. The assembly manual even alludes to it by mentioning the change from the QCX+ boards to try and avoid this problem. In reality, it can never be avoided with a single pin design (and now there is the problem of incompatible connections to the PA kits).

User interfaces have standards, both implied and explicit. This design violates the implicit standard for stereo phone plugs. All our electronic lives we plug and unplug stereo jacks with impunity. Stereos, phones, TVs, etc.  never blow up when you plug in/out headphones or speakers. At worst, they make a loud annoying click. So we are quite thoroughly trained that stereo plugs are safe to plug/unplug under power. Even with a warning label, it's still a problem because that poor label is trying to fight years of training and reinforcement of the user/operator.

The real answer is to fix the design by changing to another connector type. The change can be retro-fitted to some extent by kit builders, though at the cost of some convenience. For example, cutting the +5v trace to the PTT jack combined with Gregg's move to supply GPS power from an external power supply will totally fix the issue. Or, the power trace can be cut and another connector with 2 pins that don't short each other when plugged/unplugged (preferably polarized)  can be used to carry the power separately from the signals.

I realize that QRP Labs is not  a huge consumer products manufacturer and that its target audience is people with a certain level of technical skill so many design processes and methodologies that the big companies use don't apply, but in this case connector selection standards should have been followed. With any luck, the next PCB rev will fix this.

73,
Laszlo



Re: QCX mini 20M no output, can't adjust IQ,lo and hi. #qcx20mini #qcxmini #alignment

Ronald Taylor
 

Those voltages are all good. Those are the voltages you should get with your external DVM. The voltages on the chart are what you should see if you use the on-board DVM which has a lower impedance and loads down some of the voltages. 73....: Ron

On Wed, Jan 27, 2021 at 06:59 Khor Lai Hock via groups.io <lhkhor=yahoo.com@groups.io> wrote:
Enclose are my measurement.
Is it IC 8,9 &10 need to change??

Thank
DE 9M2KLH


Re: QCX+ no reception #40m

howard winwood G4GPF
 

Thanks Alan, you got there before I did.

On 27 Jan 2021, at 08:25, Alan G4ZFQ <alan4alan@...> wrote:

Who is the target, Howard?
I'd guess anyone who might read it before they actually build a kit.
Bad soldering of enamelled wires and not re-soldering because "they all look good" is a very common problem.

73 Alan G4ZFQ






Re: QCX mini 20M no output, can't adjust IQ,lo and hi. #qcx20mini #qcxmini #alignment

Khor Lai Hock
 

Enclose are my measurement.
Is it IC 8,9 &10 need to change??

Thank
DE 9M2KLH


Re: QCX+ no reception #40m

Chuck - K3FLN
 

Graham,
I know Hans likes this method, but if you try this you will never go back...

https://groups.io/g/QRPLabs/message/61179
--
Cheers,
Chuck


Re: QCX Mini WSPR beacon hangs

N3MNT
 

What power out?


Re: Smokey

Ted 2E0THH
 

Laszlo

This is a hobby.

Hans is not designing avionics or medical technology.
He is producing a ridiculously feature-rich transceiver kit for a fraction of the price of a shelf bought rigs.
QRP labs has allowed a wealth of old and new hams to embrace CW, some like me for the first time. The Mini was designed as a SOTA/extreme portable solution. The fact that it has retained beacon functionality I find amazing.
GPS connection and beacon use for the QCX range is well documented. 

73s Ted