A word of advice


howard winwood G4GPF
 

Groups like this  tend to be a gathering point for those building and troubleshooting kits offered (in this case) by QRPLabs.
One thing I have noticed, and this applies to a lot off other similar groups, is that there appears to be very little advice on who should/should not be building these kits.
I say this because of the obvious lack of knowledge/skills in even basic electronics that some builder seem to have.
Now, that is not to belittle anyone, we all have to start somewhere, BUT these kits are not really aimed at the beginner for a variety of reasons.
1/ Basic electronic knowledge of components, Ohms law.
2/ Basic soldering skills
3/ Basic set of tools
4/ Basic test gear
5/ Ability to read a simple schematic circuit diagram.
I have noticed on this group and on the microBitx group, that some people (usually with less than even basic knowledge) think these kits (I use the term kit loosely for the microbitx kits) should work with very little effort.
Sadly, as most experienced builders know from experience, this is not the case.
I am going to offer those who may be tempted to get into kit building, some advice based on 50+ years of tinkering with all sorts of electronics, not just in Ham radio.
How do you judge the quality of a kit?
This one is quite simple, look at the documentation.
I will say at this point QRPLabs have some of the best and most comprehensive documentation out there, and would recommend their kits to anyone who has reasonable skills in electronics.
The standard by which kits are judged goes back to the days of Heathkit, superb kits with superb step by step instructions, but certainly not cheap.
So! what level of competence should a prospective kit builder have?
To start with, a basic knowledge of components, resistors, capacitors, semiconductors, inductors.
I would have thought that most radio hams would have this knowledge but it seems I am wrong.
To be able to identify and test resistors and capacitors is a start and to have a basic understanding of their function.
Basic soldering skills are essential, you should not be practising your skills on an advanced kit like the QCX.
After 50+ years of radio building I can still get a bad solder joint, because my eyes don't always pick it up straight away, but I always go over my soldering with a magnifier and ANYTHING that looks suspicious gets a second go.
Basic tools are essential, go for the best quality you can afford, they will last you a lifetime.
a small selection of screwdrivers, side cutters, long nosed pliers to start with.
Some basic test gear such as a Digital Multimeter, and it does NOT have to be expensive. You do NOT have to know the voltage down to the 3rd,4th or 5th decimal place.
Forget things like Oscilloscopes, signal generators, Spectrum Analysers and other fancy test gear for now, they can come later when you know what they can be used for (AND how to use them).
The ability to make some basic sense of a circuit (schematic) diagram, otherwise you are on to a hiding to nothing.
This is where the likes of QRPLabs show their mettle, by not only providing very detailed construction  notes, but also detailed set up instructions with a lot of the hard work taken care of by being in the software
and accessed through the display.
Unfortunately, by making it relatively easy for Joe Bloggs to successfully build and get working, these kits, it will attract those with lesser skills to attempt something that MAY be beyond there current capabilities.
I would not dissuade anyone from having a go, but would advise to start on a few much simple projects, there are plenty of cheap soldering skill kits on Ebay that will get you going and get you skills (soldering especially) up to scratch
before you tackle something more adventurous.
Unfortunately groups like QRPLabs will by definition attract those who have had problems, and where would we be without such groups to help iron out such problems?
It is where the problems are caused, not because of the quality of the kits, but caused by the lack of skill/knowledge/understanding of the constructor.
Because it is the problems that get highlighted, that the casual observer can get the impression that these kits are not always up to scratch.
When, in fact it is the constructor that is not up to scratch.
I am not trying to put anyone off building their own gear, it is massively rewarding to operate something you have put together yourself, and would encourage anyone to have a go.
BUT, be prepared for disappointment, there are no guarantees in this game.
The BEST piece of advice I can give if you are starting out in the world of radio construction is to mate up with someone who has been doing it for a while and and can offer advice and possibly test gear you may not yet need/have.
Groups like this really are helpful but unfortunately remote, so is much harder to diagnose and get information across.
I am not trying to put anyone off, just offering some advice on being realistic when you tackle kits like these.
Just remember, there are times you just have to put things down to experience and move on to the next project.
You can always come back to the projects in the "to finish one day" bin. ( I have lots! LOL)


Albert Tatlock's Greatest Hits - Vol 1
 

Spot on.

Too many builders turn up here with nothing more than a broken penknife and
a CB swaaar meter for a toolkit, and then moan that they can't get something to work.

And then they have the cheek to blame QRP Labs for "bad" kits.


Ted 2E0THH
 

Whilst I understand the sentiments, I really would not wish for the group to become "elite" and I know you were not eluding to this Howard.
I do feel there is far too much assumption, jumping down rabbit holes with no actual fault finding. Because of the the fabulous documentation and videos Hans has provided, fault finding the QCX series is a great way to learn the process.
When I see posts saying "C4567 is obviously faulty" I am minded of  a very wise physicist who once posed the question "how do you know that?" 
73s Ted


N3MNT
 

Although experience may help in some of the issues we are seeing, I think that many of the issues people are having are caused by not carefully following the instructions.  Hans has done an excellent job of creating easy to follow assembly instructions including identifying potential pitfalls for specific steps.  Reading through the posts by those having issues, it is surprising how many are the result of missing parts, poor soldering, incorrectly placed parts etc.  There are many posts where the  builder says they have checked the solder connections several times and they are all good, only to see the resolution was to reheat one solder connection. 


Dave VE3GSO
 

I have to agree with everything said here.

The QRP-Labs kits are second to none.  Hans has even included excellent explanations of how the kits work, in the case of the QCX going through each stage, while also giving credit to where the circuit original design comes from.

The only time I have had a problem with one of these kits is when I assumed I knew what I was doing!  Of course Read the Manual set me straight!

I think the following tools essential:
Temperature regulated soldering iron with a fine chisel tip.  The cheap irons get too hot and burn out their tinning far too quickly.
Tweezers for picking up small parts.
Small needle nose pliers for bending leads. I tend to use my finger nail and finger pressure.
Small slot and Philips screwdrivers.
Flush wire cutters.
Solder wick, liquid flux, 63/37 flux core solder, Q-tips, Isopropyl alcohol for cleanup.
Illuminated magnifying glass to actually see what you are doing in good light.  I have used drugstore +2.5 reading glasses and a desk lamp, but modern LED magnifiers are pretty cheap online.

Practice on an old board.  Anybody interested in electronics must have old floppy drives, a dead printer, a motherboard, etc to practice on.

And of course, when help is truly needed, this list is here.

Dave

On Jan 23, 2021, at 09:23, N3MNT <bob@...> wrote:

Although experience may help in some of the issues we are seeing, I think that many of the issues people are having are caused by not carefully following the instructions.  Hans has done an excellent job of creating easy to follow assembly instructions including identifying potential pitfalls for specific steps.  Reading through the posts by those having issues, it is surprising how many are the result of missing parts, poor soldering, incorrectly placed parts etc.  There are many posts where the  builder says they have checked the solder connections several times and they are all good, only to see the resolution was to reheat one solder connection. 


Mont Pierce KM6WT
 

Two additional(?) points I'd like to bring out (if they're already mentioned, sorry I must have missed them).

1) Anytime you order a 1.0 version of a product, one should be prepared and accept that you will likely see some issue(s) that have not fully been ironed out.  For some, this is part of the fun, for others, they should wait for the product to mature a little, at least version 1.1 And note: every revision (1.2, 1.3..) will have more of the initial issues ironed out.  So, if you are not prepared to accept a couple of initial wrinkles, be patient, and wait for a future revision.  You will be much happier.

2) The number of issues posted is not a valid measure of the quality of the kit.  Remember, builders with issues are many many many times more likely to create a post than the builders that had complete success.  This is only natural as those with issues pool together to help one another to solve issues.  While those with successful builds are busy on the air, making contacts, and having a blast !!  :) :)

Interestingly, point 2 above can be an indicator for point 1, and vice-versa.


I remember some time ago, seeing all the posts with issues on the QCX, and I did NOT order one.  It wasn't until sometime later I ventured in with an order for the QCX+.  A tried and true successful product, plus now with a well designed factory case, AND  a Development Board plug in which I really really admire !!!   :)  :)

One more point I'd like to make in regards to QRP-Labs' Kits: Their prices are so affordable, they are well worth their Educational Value Alone.  Just examine how many builders on this forum are learning new skills, venturing into SMT rework, expanding their knowledge of circuit designs, and more.  Not to mention the sense of comradery as they swap tips, stories, encouragement, tools recommendations, etc, etc, etc.

It seems like, QRP-Labs has produced more that just fun kits to build, but a culture of individuals that share Hans' enthusiasm for the Ham Radio Hobby.


73
km6wt


Michael Greene
 

Mont,
My thoughts, exactly. I have learned so much and have never had so much fun and interesting experiences as I have building and using the QRP Labs kits!

Michael KN6IZE


geoff M0ORE
 

I have to agree 100%. I have had one kit where there was a problem with the board and I contacted Hans direct on that.

There is no point having a bench full of test equipment if you don't know how to use the results that it gives. No scope will tell you that the fault is due to C???, you have to be able to diagnose the symptoms and test results.

A lot of practice on equipment that is working will build up confidence in the testing, no point learning on a kit that has never worked.

We were all beginners once and have built up our skills over many years. I was fortunate to work in an environment where I had to repair faults ( sometimes after being called out in the early hours ) with the clock ticking and the customer  or control centre breathing down my neck to get the systems back.

Start on the easier kits to build up the confidence and skills.

On 23/01/2021 12:05, howard winwood G4GPF wrote:
Groups like this  tend to be a gathering point for those building and troubleshooting kits offered (in this case) by QRPLabs.
One thing I have noticed, and this applies to a lot off other similar groups, is that there appears to be very little advice on who should/should not be building these kits.
I say this because of the obvious lack of knowledge/skills in even basic electronics that some builder seem to have.
Now, that is not to belittle anyone, we all have to start somewhere, BUT these kits are not really aimed at the beginner for a variety of reasons.
1/ Basic electronic knowledge of components, Ohms law.
2/ Basic soldering skills
3/ Basic set of tools
4/ Basic test gear
5/ Ability to read a simple schematic circuit diagram.
I have noticed on this group and on the microBitx group, that some people (usually with less than even basic knowledge) think these kits (I use the term kit loosely for the microbitx kits) should work with very little effort.
Sadly, as most experienced builders know from experience, this is not the case.
I am going to offer those who may be tempted to get into kit building, some advice based on 50+ years of tinkering with all sorts of electronics, not just in Ham radio.
How do you judge the quality of a kit?
This one is quite simple, look at the documentation.
I will say at this point QRPLabs have some of the best and most comprehensive documentation out there, and would recommend their kits to anyone who has reasonable skills in electronics.
The standard by which kits are judged goes back to the days of Heathkit, superb kits with superb step by step instructions, but certainly not cheap.
So! what level of competence should a prospective kit builder have?
To start with, a basic knowledge of components, resistors, capacitors, semiconductors, inductors.
I would have thought that most radio hams would have this knowledge but it seems I am wrong.
To be able to identify and test resistors and capacitors is a start and to have a basic understanding of their function.
Basic soldering skills are essential, you should not be practising your skills on an advanced kit like the QCX.
After 50+ years of radio building I can still get a bad solder joint, because my eyes don't always pick it up straight away, but I always go over my soldering with a magnifier and ANYTHING that looks suspicious gets a second go.
Basic tools are essential, go for the best quality you can afford, they will last you a lifetime.
a small selection of screwdrivers, side cutters, long nosed pliers to start with.
Some basic test gear such as a Digital Multimeter, and it does NOT have to be expensive. You do NOT have to know the voltage down to the 3rd,4th or 5th decimal place.
Forget things like Oscilloscopes, signal generators, Spectrum Analysers and other fancy test gear for now, they can come later when you know what they can be used for (AND how to use them).
The ability to make some basic sense of a circuit (schematic) diagram, otherwise you are on to a hiding to nothing.
This is where the likes of QRPLabs show their mettle, by not only providing very detailed construction  notes, but also detailed set up instructions with a lot of the hard work taken care of by being in the software
and accessed through the display.
Unfortunately, by making it relatively easy for Joe Bloggs to successfully build and get working, these kits, it will attract those with lesser skills to attempt something that MAY be beyond there current capabilities.
I would not dissuade anyone from having a go, but would advise to start on a few much simple projects, there are plenty of cheap soldering skill kits on Ebay that will get you going and get you skills (soldering especially) up to scratch
before you tackle something more adventurous.
Unfortunately groups like QRPLabs will by definition attract those who have had problems, and where would we be without such groups to help iron out such problems?
It is where the problems are caused, not because of the quality of the kits, but caused by the lack of skill/knowledge/understanding of the constructor.
Because it is the problems that get highlighted, that the casual observer can get the impression that these kits are not always up to scratch.
When, in fact it is the constructor that is not up to scratch.
I am not trying to put anyone off building their own gear, it is massively rewarding to operate something you have put together yourself, and would encourage anyone to have a go.
BUT, be prepared for disappointment, there are no guarantees in this game.
The BEST piece of advice I can give if you are starting out in the world of radio construction is to mate up with someone who has been doing it for a while and and can offer advice and possibly test gear you may not yet need/have.
Groups like this really are helpful but unfortunately remote, so is much harder to diagnose and get information across.
I am not trying to put anyone off, just offering some advice on being realistic when you tackle kits like these.
Just remember, there are times you just have to put things down to experience and move on to the next project.
You can always come back to the projects in the "to finish one day" bin. ( I have lots! LOL)


R. Tyson
 

Excellent comments. It is obvious that some people are building these kits and have poor soldering abilities, we have seen some of the photos, or little or no experience of construction. The instructions are excellent and the products are excellent. It would be better for someone with no experience to start with some simpler projects. I begin to wonder when I see questions on where to obtain components, that does not indicate any previous experience of constructing. Everyone has to start somewhere but diving straight into a complex project is not necessarily a good idea. Gaining experience on soldering and easier projects would improve the prospects of having a working radio transceiver after assembling one of these kits. Work they do when assembled correctly, are value for money and great fun to use. An experienced constructor will usually have them working first time but that comes from experience.

Reg            G4NFR


howard winwood G4GPF
 

I do hope I did not come across as elitist, it certainly was not my intension, mearly to offer some advice to newbies, to avoid too much disappointment when things don’t work.
Whilst there are lots of people who have successfully built their own equipment, I CAN assure you NOT everything works first time.
We are all fallible and can make mistakes, sometimes really stupid ones, it is just that we have built up experience in troubleshooting that allows us to dig ourselves out of the deep hole we have got ourselves in.
That is what differentiates the experts from the beginners.
Please don’t be put off, just have your eyes wide open.
best wishes to everyone

On 23 Jan 2021, at 16:06, R. Tyson via groups.io <tysons2@...> wrote:

Excellent comments. It is obvious that some people are building these kits and have poor soldering abilities, we have seen some of the photos, or little or no experience of construction. The instructions are excellent and the products are excellent. It would be better for someone with no experience to start with some simpler projects. I begin to wonder when I see questions on where to obtain components, that does not indicate any previous experience of constructing. Everyone has to start somewhere but diving straight into a complex project is not necessarily a good idea. Gaining experience on soldering and easier projects would improve the prospects of having a working radio transceiver after assembling one of these kits. Work they do when assembled correctly, are value for money and great fun to use. An experienced constructor will usually have them working first time but that comes from experience.

Reg            G4NFR


nz0tham@...
 

I agree and it's not elitist at all IMO.  I have built a lot of kits over the years including an Elecraft K2/100 ad I would not call the QCX series a beginners kit at all.  It's a great design and Hans has done a wonderful job of creating detailed and easy to read instruction manuals but some proven experience in building simpler kits goes a long ways when it comes to building the QCX.   I say this coming from a very non technical education (degrees in Psychology and Business) and career background.  All my electronic knowledge is solely from being a ham for 39 years.

73, Bill NZ0T


David Fine
 

Howard, I agree with your comments, however, unfortunately by the time the new builder gets to the advice/help provided here it is often times too late.  He has already jumped in above his capabilities.  Perhaps there should be a grading scale added to the kits indicating the degree of difficulty in, not only construction of the kit, but in the difficulty of troubleshooting the kit and a list of test equipment that might be needed to do the troubleshooting if necessary.  The QCX-mini most likely cannot be troubleshot using a $5 Harbor Freight multimeter and aforementioned broken pen knife.  Dave, W0DF


Alan G4ZFQ
 

The QCX-mini most likely cannot be troubleshot using a $5 Harbor Freight multimeter and aforementioned broken pen knife.
Dave,

Seems to me several have almost been repaired like that. A scope has been bypassed by guessing what IC(s) to replace.

73 Alan G4ZFQ


howard winwood G4GPF
 

Oh! dear, I need to buy some more tools :-)

On 23 Jan 2021, at 19:49, David Fine <dfine100@...> wrote:

Howard, I agree with your comments, however, unfortunately by the time the new builder gets to the advice/help provided here it is often times too late.  He has already jumped in above his capabilities.  Perhaps there should be a grading scale added to the kits indicating the degree of difficulty in, not only construction of the kit, but in the difficulty of troubleshooting the kit and a list of test equipment that might be needed to do the troubleshooting if necessary.  The QCX-mini most likely cannot be troubleshot using a $5 Harbor Freight multimeter and aforementioned broken pen knife.  Dave, W0DF


Dennis AG7IN <denqrp@...>
 

Nice thread here with wise advice. Over the years, to this will add as mentioned below with familiarizing parts and learning the schematic, a free step, for someone
reading this who is about to start and excited and learning, of laying out the parts on paper taped to the bench/desk, sort them, measure them, mark the values below on
the paper, and find each part in the schematic, and this is where a beginner can learn: get to know if a part is just a pull up resistor or power filter capacitor
or in a more critical position, and are there matched sets of similar values, and will match up those measured part values and write part numbers below that, and put parts
less on value into the less critical roles. For me, that really helps to familiarize and locate missing/incorrect or out of tolerance parts and get boards working well with analog
components.

Would also suggest a board holder, they are low-cost, clean the board copper with 99% alcohol before soldering, and then clean the solder side again when done.
Adding to the great note below of a magnifier, a head mounted set with LED helps free hands, and very important, heartily agree with the posts suggesting a good temperature
controlled small iron for precision work, and small tip. For beginners to soldering, as mentioned below, practice, try a simpler kit and learn to solder well first.

--
73,
Den AG7IN


Mike Besemer - WM4B
 

But that's not troubleshooting... that's loading up the parts-cannon and firing at point-blank range. Yes, the radio gets repaired (maybe) but no troubleshooting has been done and that method is ripe to produce maintenance-induced faults.

Mike
WM4B

-----Original Message-----
From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Alan G4ZFQ
Sent: Saturday, January 23, 2021 3:04 PM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] A word of advice

Dave,

Seems to me several have almost been repaired like that. A scope has
been bypassed by guessing what IC(s) to replace.

73 Alan G4ZFQ


Fred Spinner
 

The shotgun approach is often even used in industry.  Depends if labor is more expensive than parts or not.  It does not matter if you trouble shot or not if the final product passes all tests.  So yes, you can do a valid repair that way.  With the reliability of the opamps on the board from the assembly house, the repair is likely better with that approach. 


On Sat, Jan 23, 2021, 1:57 PM Mike Besemer - WM4B <mwbesemer@...> wrote:
But that's not troubleshooting... that's loading up the parts-cannon and firing at point-blank range.  Yes, the radio gets repaired (maybe) but no troubleshooting has been done and that method is ripe to produce maintenance-induced faults.

Mike
WM4B

-----Original Message-----
From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Alan G4ZFQ
Sent: Saturday, January 23, 2021 3:04 PM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] A word of advice

Dave,

Seems to me several have almost been repaired like that. A scope has
been bypassed by guessing what IC(s) to replace.

73 Alan G4ZFQ












Mike Besemer - WM4B
 

I don’t disagree, but one must recognize the potential to introduce maintenance-induced failure.  Those that lack a means of troubleshooting are also likely to lack skill at soldering SMD devices, which could be a major problem with the Mini. 

 

I just want to make a distinction between troubleshooting and repair; they are different animals.

 

Mike

WM4B

 

From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Fred Spinner
Sent: Saturday, January 23, 2021 4:14 PM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] A word of advice

 

The shotgun approach is often even used in industry.  Depends if labor is more expensive than parts or not.  It does not matter if you trouble shot or not if the final product passes all tests.  So yes, you can do a valid repair that way.  With the reliability of the opamps on the board from the assembly house, the repair is likely better with that approach. 

 

On Sat, Jan 23, 2021, 1:57 PM Mike Besemer - WM4B <mwbesemer@...> wrote:

But that's not troubleshooting... that's loading up the parts-cannon and firing at point-blank range.  Yes, the radio gets repaired (maybe) but no troubleshooting has been done and that method is ripe to produce maintenance-induced faults.

Mike
WM4B

-----Original Message-----
From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Alan G4ZFQ
Sent: Saturday, January 23, 2021 3:04 PM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] A word of advice

Dave,

Seems to me several have almost been repaired like that. A scope has
been bypassed by guessing what IC(s) to replace.

73 Alan G4ZFQ











Arv Evans <arvid.evans@...>
 

There are kits, and there are kits.  Some would have you solder all the parts
to a bare PCB, and others have all the parts already soldered to the PCB. 
If your kit has all the parts pre-soldered to the PCB and only requires off-board
connections to be added then you probably do not need thousands of dollars
of test equipment and the learning curve that goes along with operating it.

_._


On Sat, Jan 23, 2021 at 8:00 AM Dave <VE3GSO@...> wrote:
I have to agree with everything said here.

The QRP-Labs kits are second to none.  Hans has even included excellent explanations of how the kits work, in the case of the QCX going through each stage, while also giving credit to where the circuit original design comes from.

The only time I have had a problem with one of these kits is when I assumed I knew what I was doing!  Of course Read the Manual set me straight!

I think the following tools essential:
Temperature regulated soldering iron with a fine chisel tip.  The cheap irons get too hot and burn out their tinning far too quickly.
Tweezers for picking up small parts.
Small needle nose pliers for bending leads. I tend to use my finger nail and finger pressure.
Small slot and Philips screwdrivers.
Flush wire cutters.
Solder wick, liquid flux, 63/37 flux core solder, Q-tips, Isopropyl alcohol for cleanup.
Illuminated magnifying glass to actually see what you are doing in good light.  I have used drugstore +2.5 reading glasses and a desk lamp, but modern LED magnifiers are pretty cheap online.

Practice on an old board.  Anybody interested in electronics must have old floppy drives, a dead printer, a motherboard, etc to practice on.

And of course, when help is truly needed, this list is here.

Dave

On Jan 23, 2021, at 09:23, N3MNT <bob@...> wrote:

Although experience may help in some of the issues we are seeing, I think that many of the issues people are having are caused by not carefully following the instructions.  Hans has done an excellent job of creating easy to follow assembly instructions including identifying potential pitfalls for specific steps.  Reading through the posts by those having issues, it is surprising how many are the result of missing parts, poor soldering, incorrectly placed parts etc.  There are many posts where the  builder says they have checked the solder connections several times and they are all good, only to see the resolution was to reheat one solder connection. 


Alan G4ZFQ
 

On 23/01/2021 21:31, Mike Besemer - WM4B wrote:
I don’t disagree, but one must recognize the potential to introduce maintenance-induced failure.
Yes, but we all began once.
I certainly did not start with any real knowledge or test equipment.
I had to make do with what I had, eventually got a little better, learnt by destroying things:-)

73 Alan G4ZFQ