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Thanks Ron! I sent you an email so we can set it up.

On Tue, Feb 25, 2025 at 06:16 PM, Corey KC9RAV wrote:

assembling a QRP labs kit doesn’t require ESD protection. It doesn’t hurt, but there isn’t any major ESD risk.?

And that is why some people have failures in their assembly, or after operating for a time (due to a weakened part).

There is indeed ESD risk.

Yes, the ESD risk is minimized since most of the parts have ESD protection on their input pins, and are pre-assembled onto the CCA.?

And the risk is not as critical (like Jerry mentioned) since we are hobbyists, not making mission critical gear - and we can easily fix it if it breaks.

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But the highly integrated parts in the Q*X with fine internal lithograpy (all of the ICs except the 3.3V regulator) can indeed be damaged with careless handling.?? ESD may not cause failure immediately, but may weaken a part that may then fail later.? Yes, even with the ESD protection on their pins - it just takes a larger ESD event.? The pins are typically ESD protected to 2000V, which protects well if handled carefully.? But picking up a styrofoam coffee cup from your work table and brushing it against the cuff of your shirt can generate well over 20,000 volts of static on your hands - then touching one of those devices without discharging yourself will indeed damage it.? Thankfully most of us don't use styrofoam on or near our work surfaces, but many other materials, including carpeting, the covering on your chair, your chair's roller wheels, and even your clothing can readily generate high static charges, unless these materials are of the anti-static variety.? And how many of us have checked??

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Sorry for the tirade, but I had to take ESD refresher training every 6 mo during much of my career.? And it was interesting to learn of the common materials and simple body movements that can generate static tens of times greater than the typical 2000V ESD protected device can withstand.? So unless you know you are safe, use an ESD mat and ground yourself after moving or wear a wrist strap.? Assembly areas where I worked have chairs and floors that are known not to generate static.? And we still had to wear our wrist bands or shoe straps, and work on ESD mats that were tested and qualified every 3 mo.? Yes we worked on mission critical devices, and we had to avoid all ESD risk, unlike hobbyists.?

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After the item is assembled, the risk is lower, because there are many paths to dissipate ESD, and you usually don't directly touch an ESD sensitive device without previously discharging the ESD through a benign path.? And maybe that's why we don't often kill the ICs in qrp-labs kits.

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But please don't believe that there isn't any ESD risk unless you are specifically minimizing it in some way.

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Stan KC7XE

My two cents, assembling a QRP labs kit doesn’t require ESD protection. It doesn’t hurt, but there isn’t any major ESD risk.?

On Tue, Feb 25, 2025 at 11:24 AM, Stan Dye wrote:

On Tue, Feb 25, 2025 at 05:17 AM, spaine wrote:

A good ESD work surface is conductive

The correct word here would be "dissipative" - something that quickly dissipates static charge, but has a very high resistance to normal electrical currents.??

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As Allison said, inexpensive ESD mats are safer, and they are easy to get and use.? And even the $20 ones on Amazon, complete with wrist strap, will last a very long time.? I encourage all assemblers of qrp-labs kits to get one and use it.

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On Tue, Feb 25, 2025 at 05:43 PM, Bryan Curl wrote:

the 1mohm resistor Don Brant mentioned is important for the purpose of allowing static charge to go to ground somewhat slowly in order to not make a spark.

It is also a personal safety item, in series with the wrist strap it limits your current to ground in the event you contact a hot wire; it is best not to have a grounded conductor around your wrist when working with electricity.

73, Don N2VGU

I too have bought bad Chinese irons.? The first one I bought showed the "intended" temperature,

from the moment you plugged it in, giving no idea how hot the tip really was.

It was also too weak to deal with something like the QMX ground plane connections.

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This one addressed both those issues: ?

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A well chosen Weller or Hakko might work better, at 10x the cost.

There might well be Chinese irons out there that are of equal quality, but not at $16

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Jerry, KE7ER?

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On Tue, Feb 25, 2025 at 01:43 PM, Bruce Akhurst wrote:

In a high value manufacturing environment, you do everything you can to avoid static damage.

Even rarely occuring failures can cost big money, perhaps even the loss of a large sale.

I think most hobbyists are a bit more relaxed than that.

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I'd bet an honest survey of Q*X kit builders would find that less than half have a static mat.

Most of the parts we use are either not inherently sensitive to static or they have protection

devices at each IO pin.? Protection is typically a Schottky diode from pin to ground and another?

from pin to Vdd, these discharge any hit that exceeds normal signal voltages.

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I guess the most sensitive part that we regularly work with would be the gate of the BS170's.

Be especially careful with static control when replacing those.? Once parts are soldered down

to the board, they are usually connected to other stuff that helps discharge a static hit.

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When I approach sensitive gear, I first touch a ground point to bring the device to the same potential?

as my body.? If static is in the air, I continue touching that equipment ground while working on it

as much as I can. Static sensitive parts such as the BS170's should be kept in the anti-static?

bag till you are ready to solder them into place.? If you first touch the bag (perhaps to open it)

before touching the sensitive part, no damage will occur. Then with the other hand I'd touch

the equipment ground before bringing the part to the equipment.? If you follow procedures?

such as this, most hobbyists should not have trouble with static damage.??

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My workbench does have a static mat, but I am not always at my workbench.

When at my bench, I generally don't strap in with a wrist strap, but instead lay an arm across

the static mat to establish a connection.??

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Now retired, but at work in an engineering environment, we generally followed procedures

like those above without getting yelled at.? It was generally our own design, and if something

were to fail we were well qualified to fix it.? I can't think of a single case where I felt I had

caused static damage over several decades of work.? Procedures in manufacturing

were somewhat more strict.

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When designing a board I often add a series resistor of perhaps 100 ohms to each sensitive

IO pin that goes out to a customer accessable connector if that won't compromise the intended

purpose.? The combination of the series resistor plus the protection diodes makes it pretty much?

bullet proof, unless they plug that wire into a wall socket.

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Jerry, KE7ER

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I had to use 4.6.2 hamlib it solved my QMX issues 4.6.1 hamlib QMX is broken.

Hi Justin. I’d be happy to repair that for you if you like. I’ll write you off the group with details.?

Ron

Hey all!

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Just got a cheap lightning to usb “camera adapter” to try to do some ft8 while on lunch break using iFTX.?

I’ve noticed I can receive and decode ft8 no problem, but when I call cq audio only comes out my phone and doesn’t go into the radio.?

I have VOX enabled and all other settings are standard. Is there some config item in the radio I’m missing?

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72

Jeff

KB3TVP

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Adapter in question:

IVSHOWCO Lightning to USB Adapter... https://www.amazon.com/dp/B09H2PZTG2?ref=ppx_pop_mob_ap_share

Not at all convinced by this . .? ??

I use an antistatic mat as my bench covering at all times, grounded, linked to PSU, linked to soldering iron.? ?It runs to the front of the bench so my arms rest on it automatically but for known super-sensitive work I wear a strap too.? ?

They wear out in time but the next is already in the cupboard.? ?ps their surface resistance is very high but a good GigOhm meter or tester will see it over a few inches and a HV insulation tester easily for a periodic test.? Their aim is to drain static slowly, do no harm to live circuits parked on them and also be non skid . .?

Lloyd,

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The components were produced on a QIDI Plus 4 printer, utilizing a mix of PLA and PLA-CF, with plans to potentially print another unit in PPS-CF for enhanced durability. The PLA parts were printed using a fully calibrated .4mm nozzle, following the Orca slicer calibration process, which was also applied to the PLA-CF filament. For the front panel, a .2mm nozzle was used with PLA-CF to achieve sharper lettering and reduce filament layers. I included a photo of the raw front panel with primer to illustrate the clarity of the lettering, although the white paint application slightly distorted the letters. After calibrating the filaments and printing the parts, a self-etching primer was applied to reveal the layer lines, followed by a quick wet sanding with 400 grit and a layer of autobody spot filler, which was also sanded with wet 400 grit. Once the layer lines were filled, another primer coat was applied, followed by wet sanding with 1000 grit and two to three coats of green paint, sanding between each layer. After the final green paint coat dried, a matte clear coat was added to seal the surface and prevent the white paint for the lettering from contaminating the green paint.
Next, I then applied white paint to the lettering wiping clean with a dry towel this left some paint smearing on the part surface which was sanded off once dry with wet 2000 grit paper. Then a final coat of clear matte finish and phew its done.

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73, Dave

W6MQI

I recently ordered a qty of board assys from JLCPCB which pushed the $800 limit but FedEx shipped the order through Incheon, South Korea.?

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73 Kees K5BCQ

Thanks for the reply, Ron!

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Yes, I really meant C31. I think what happened is I actually broke half of the component off the board with the clamp I use for soldering. It was clamped on the side of the board nearest C31 and I wasn't careful when I clamped it and broke half the component right off the pad.?

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Since I made this post, I actually gave it a little tug with a plastic tweezers and the whole capacitor came right off the board. I think I lifted the solder pads right off the board when I attempted my "repair." I had the soldering iron cranked up to max temp to desolder those big headphone jack pads and I didn't turn it back down when I patched C31.?

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So, I've created a bit more of a headache for myself now.?

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But: It gets even worse. I decided I'd make a temporary repair by jumpering a thru-hole capacitor between R41 and the nearest neighbor to C31 and I lifted R41 right off the board too. Burnt the SMD pads right off again, even with lower power. I guess I'm terrible at SMD repairs.

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Any suggestions for repairing this? I guess I need to find a way to replace R41 and C31 without any pads left now. I could scrape away some solder mask and try to wire a few thru-hole components in series, but for now I've just given up.

I have the lovely task of testing all my company's esd surfaces and continuous static monitoring devices.??

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A couple of things I read here need to be said.?

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1. paper (Manila folders included)? is a static generating material.? It will create a static charge just lifting it off of cirtain material.? keep it 12"+ away from any static sensitive device.?

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2. the 1mohm resistor Don Brant mentioned is important for the purpose of allowing static charge to go to ground somewhat slowly in order to not make a spark.

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If you're work surface is properly grounded and you are not wearing a wrist strap with 1mohm resistor embedded,? then your charge will travel on the work surface to ground and may effect anything lying on the that surface.? we even have to remove all static devices from the surface before doing a surface test for this reason. Profe of receipt...I had a lightning strike that went across my metal desk and blew avhf/uhf radio up that was not even connected. Okay, maybe lightning is overkill example of static discharge but the principle is the same.?

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I'll shut up now.??

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regards,
Bryan, N0LUF

There's a difference between minimum soldering iron and the? 'OMG I should have bought this 10 years ago' soldering Iron you'll buy eventually.

While components and PCB's are getting smaller the arrival of on-PCB heatsinking areas and multi layer boards has upped the challenge for a good joint without component damage (= Rapid heat transfer and done )?

I use a 90W temperature controlled Weller with 2.5mm chisel bit 99.9% of the time.? ?It has ridiculous, stable, heat generation and transfer capabilities and makes great joints quickly when a smaller /less powerful iron would keep me waiting (And frying the associated components for 30 - 60 seconds at a time.? It also has a useful LCD Display showing how much power (=heat transfer) is actually going into the joint which helps improve technique.?

I use 325°颁? for Leaded and 355°颁 for unleaded.? ?Due to high power and temperature control of my iron these do not need fiddling with to try to build up 'extra heat' in the 'too small iron'?

If you think you will be in this hobby in 3 years or more spend the money on a good one now? . . .?

I do have a '60W' Chinese temperature controlled iron in the car for unexpected emergencies. . .? ? ?It often does the job but but not always and can even end up stuck to really large solder areas which is fairly awkward? . . .? ?It would probably let me assemble a QRP Labs kit though but there's 0% chance I'd want to by choice with a better one on the bench.


A paint stripper heat gun will be disaster on PCB's? - again a decent one will change your life early on reworking SMD boards

I have been using low-band QMX with 50W amp for several months with 018 software. Today I uploaded the .027 firmware and that process went as normal, but afterward the QMX does not transmit. Tests look all OK (bias, SMPS voltages,supply 8.9V, Tx voltage 7.5) but on transmit 'T' the power is 0 or flickering 0.1W, but a valid 1.1 SWR (dummy load). The power meter on the dummy load does indicate a small output, about 100 mW.

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I tried reloading the .018 firmware, but still no TX.? I tried a factory reset from the menu. Then I used the jumper to force bootloader reloaded .027 firmware, went through replacing settings and condition is still only tune level output.

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I also have a high band QMX and I uploaded the .027 firmware to it a few days ago with no problems and have been using it successfully on 10 and 15 which has be quite open lately. This success led me to put the .027 firmware into the low-band rig.

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