Ham Radio - Building the QRP Labs QCX transceiver kit.

[@ianboard3555]

Very nice. I just passed the license exams last night (took T and G) and going to build one of these. If I may toss out a suggestion: I do assembly on a cookie sheet. It saves running around looking for teeny parts that are invevitably dropped.

[@davecasler]

Well done. I'll look at it again after mine arrives. I'm looking forward to it, but they're sold out of 40m kits at the moment.

[@warplanner8852]

I am in the same boat as David Casler - awaiting the arrival of the 30- and 20-meter versions - but am grateful for this excellent video by Kevin. These videos can become ponderous but he clips right along and points out the trouble spots.

[@simonj48]

Blu-tack is pretty good alternative to helping hands. Just a bit in to the corners of the pcb and it'll not move around. you can use it to temp secure the components to the board for soldering as well.

[@Liberty4Ever]

I like short snappy videos but this long video was perfect. The kit build was detailed and needed this much detail in the video. I've built a lot of electronics and it was interesting to see your soldering tricks which were identical to ones I have evolved over the decades. I've watched several of your videos and this one pushed me over the top. I'm heading to Patreon to support these excellent videos that I've enjoyed so much. I think I'm going to build one of these kids. I look forward to the next video in this series... just after I visit Patreon to show some appreciation. :-)

[@julianopificius6910]

I thought exactly the same as you about the soldering and assembly tricks, Liberty4Ever; a couple of decades (omigosh, I just realized it has just come up on five decades for me now!) of electronics hobby and career teaches one a lot, doesn't it? :-) I'm still waiting for my 40m kit to arrive - should be late next week with any luck - I feel like a kid 'cos I can't wait! Watching Kevin lead us through the assembly, I'm extremely impressed with the quality of the manual. I worked for Heathkit for a while back in the UK many years ago, putting together kits people had attempted to build, and I don't think I've seen an assembly manual that even came close to the Heathkit manual - until now. Getting a kit working that has never worked before and might have dry solder joints, not to mention bad/destroyed/mis-oriented components teaches one a lot about diagnostic techniques, patience, and attention to detail. I really value that period of my career.

[@ksb2112]

Nice! I'm building the 40m kit as well and it was reassuring to see that the T1 coils are indeed very tightly packed in a working build.

[@davidhughes7565]

Excellent video! Just ordered one! I think the instruction manual is formatted for A4 paper, that may explain the miss alignment òf images and text!

[@aramb]

Very helpful, especially in terms of looking out for the "gotchas"! The new version out now, with the larger board, and better i/o layout, looks like a no brainer value- added thing, at only $6 more than the original. Just can't decide which band to get!

[@dancingbear6239]

Nice job. My advice: invest in a soldering station with a pencil tip; get a Pan-a-vice to hold the board; use finer solder. Yours is a bit too thick. To hold the IC’s I wrap an elastic around the board over the IC then place a small piece of wood between the IC and elastic to hold it in place while I solder.

[@ri3cjoh]

I like this intro better. I also like the upper right bug you put on there that's very classy. This makes me want to solder something together and videotape it.

[@gsansoucie]

Excellent video. Just found out about this kit from a CW FaceBook group and yours is the first video I watched. This looks like the rig I was looking for. I get the back problems too, for me I use a back brace that has allowed me to go longer.

[@mikedavis1127]

Thanks for making this vid I referenced it a few times when building mine, I enjoyed the kit with exception of t1 but after ordering some mag wire from what's left of radio shack and giving it a few more tries I got it almost dead on what it should have been. The slight difference in the mag wire made mine a few turns too capacitive but it still tuned, I'll take a few turns out and get it peaked better, my var cap on that circuit is barely engaged so a turn or two should let me engage the var cap a but more giving some more fine adjustment. But that said only actual problem I had was my Vol knob shorted was probably something I did, but of schmoo may have found its way in there but I had an old cb that had plenty knobs, replaced the Vol knob with one from it and all is right in the world again. Am getting 18.3v peak rf on a dummy load with 13.6v supply which is just north of 5w. Now that I have a Vol knob wired instead of mounted, I'll probably go back and remote the encoder and screen and figure a good solution for remoting the two little buttons, I've got a bunch of stuff with nice push buttons if I can figure a way to mount and wire them, think I'll have to scavenge enough for an amplified speaker as well, head phones are fine but id actually like to use the typical Vol Knob as the gain and use a second Vol knob to sort the actual speaker volume

[@mbak7801]

When you were adjusting the trimmer capacitor you were pressing down on the trimmer which tends to increase the capacitance by squashing the plates. This was made worse by the shape of your trimmer tool. This means the alignment was wrong. I think it looked better before you adjusted anything. Maybe try a ceramic adjuster and hold it so the tip just goes into the screwdriver slot and then turn without pressing down. A bit fiddly but seems to work better when I have used them.

[@JohnDuncan0347]

Great job! Watched most of the video while watching my Houston Astros play the A's. I never thought I'd be this interested in building but it looks like it would be a blast.

[@aurtisanminer2827]

This was the first time I have heard the term ‘rock bound’. Makes sense!

[@aurtisanminer2827]

@Bryan Manuel fuck off bot.

[@caulktel]

Cool video Kevin. I didn’t know you had ordered one of these also. Mine, number 628, has shipped but has not arrived yet, should be any day now. Mine will be for 20 meters. It really is a great rig for 49 bucks. I look forward to your review.

[@daveb5041]

I just did a board like that:Solder until back hurts then lie down. Morphine helps you get more done.

[@MarkPentler]

The QCX I have had two extra 104 capacitors and an extra 103 capacitor. I’m terrified I’ve missed something out!

[@davidj.wilcox6053]

Dip your solder wick in rosin type flux. It will draw most of the solder out and work much better than the plain solder wick. Dave K8WPE

[@karlschwab6437]

Excellent, excellent! Keep 'em coming on this rig; I am still waiting for my 20m kit to arrive! 73, Karl

[@surgingcircuits6955]

Kit Received. Thx for your vids. Very Helpful!

[@eminusipi]

When you wound that toroid did you use a wire shuttle?

[@prestonshute7243]

Great video, going to order mine next month. 73 wd4dda

[@o2bnov0307]

Such a great video. Looks very aggressive for a first-time kit builder. The only ham gear I have with me, currently living outside the US, is a dual-band HT and my Bencher keyer. Any advice, before I order the kit? TNX de David AE4LH

[@kb5hxt]

great tips. i have built one of their kits in the past, but never got it to work with my RasbPi... I hope they still make this kit, it looks like my next build. 73 de kb5hxt

[@Ronbob59]

Kevin... Heat the solder up and stick a toothpick in the hole. Solder cools but doesn’t stick to the toothpick... Ron

[@loughkb]

Good tip!

[@jake2213b]

I am in the same shape as you. A very bad back that is robbing us of the times we want to do. By the way you found a neat kit. I hope it works they way you want it to work.

[@DAVIDGREGORYKERR]

I thought that the 14 leg integrated chip was a 74AC74 used as a Johnson counter driving a 74HC152 or a PI5V331 chip driving a AF phasing combiner but it seems to be a 74HC00, it doesn't look like the input to the QSE isn't balanced but it now seems that it comes from the very tiny quadrature synthesis chip, The assembly sequence is not the same as the assembly sequency for other kits where you install the small parts first and the large parts last. I would have thought that VN66AF VMOS transistors would been the right as the specified ones look a little small to be used for 5W out

[@QRPLabs]

The 16-pin SMD chip is a FST3253 used as Quadrature Sampling Detector (QSD). The Synthesiser is the tiny 10-pin Si5351A to the left of that. The synth produces two outputs in quadrature that drive the QSD directly without requiring a 74AC74. The 14-pin DIP chip you mention is a 74ACT00 which drives the gates of the MOSFETs in the Class-E amplifier and arranges certain gating functions such as enabling the built-in signal generator to route through to the front end during the alignment procedure. 73 Hans G0UPL qrp-labs.com

[@DeeegerD]

Nice transciever - good price!

[@petrok1rp254]

Congrats Kevin! My QCX40 waiting for my coming back from business trip to assy and run too...:) 73 - Petr, OK1RP

[@bloguetronica]

Nice! It decodes Morse!

[@commanderia58]

Nice transciever.

[@VE3IPS]

kevin, my soldering iron is like yours if I dont use a mt gun. I ordered a proper soldering iron that has smaller tips as this board looks very tight. c u on 40m cw

[@Penfold8]

I would get a smaller gauge soldering wire if I were you. This gauge looked really big. I would suggest a .31 at maximum when soldering PCBs for through hole.

[@caulktel]

Oh, BTW, a new revision of the firmware was released this morning, I think it is 1.00C

[@DeeegerD]

Is the source code available? Might be nice to use a 4x20 display and show the morse on the lower two lines, etc...

[@caulktel]

Digger D It’s my understanding that the code can only be uploaded to the chip and not modifiable, locked fuse bits. I could be wrong.

[@DeeegerD]

Thanks, was wondering if the source code was available (not the image file) but perhaps in time. I imagine it isn't written in C++ (which is fine).

[@StephenFarthing]

Digger D the source code isn’t available and I doubt if it will be. One of Hans’s earlier kits was copied by another ham who then passed it off to another manufacturer as his own work. Since then Hans has not put his source code in the public domain.

[@DeeegerD]

Ok, makes sense - thanks for the info.

[@prestonshute7243]

Well mine is on order and there are only 1000 ahead of me. You might want to revisit the torrid windings. Seem to me some folks have the most problems with the large T1 I think that has the multi windings. Anyway I’ll be reviewing your video when mine arrives. 73 wd4dda

[@alanritchie1968]

WHEN YOU ARE PUTING IN YOUR CONPONETS TRY A LUMP OF BLUE TAK OVER THEMTO HOLD TO BOARD TOSTOP THEM FALLING OUT WHEN YOU TURNOVER

[@jdmeaux]

Don't feel bad. I have 4 cans of pasta sauce under the legs of my computer table. Moe k2jdm

[@MrTimowens]

This may be a task that's extremely hard or impossible to do. Would there be any way to add a frequency for voice. Somewhere between 7.100 and 7.300. And be able to make this switchable between cw and voice. This would be only for personal coms in an extreme emergency. My thoughts are on the lines of the ww2 paraset radio.

[@daveb5041]

How does the arduino remember the settings when you turn it off? I thought the only way to do that was by reprogramming it through the data cable to the pc. Also the weather is never good in Indiana. ;)

[@loughkb]

There is actually a way to write to the flash memory in the arduino within the code to store things between boots. I don't have the details handy, but a google search will probably turn something up.

[@Feakre]

My question is simple - Did you enjoy building this kit? I got the impression from the way you were speaking sometimes was that it was a bit of a chore.

[@loughkb]

Yes. My back makes working at the bench painful, I think that was bleeding through a bit.

[@dalemyers5096]

I think I'll buy the 4 band hambuilder ssb/cw. But put the speaker in the case. By moving a wire from the speaker/mic. It's cheap, 199. For a 10 watt 80/40/30/20 transceiver. It's a eBay buy.

[@WA8QFE]

I'm working on the QCX first , have the Hambuilder rig and sometime in the future I'll build the OZQrp rig I bought....hope sometime between builds, I have a little time to operate....hi....hi Lee, WA8QFE

[@malchaschwatrz5706]

Well done and thank you. I might just get one now!

[@eddy2561]

I built the QCX+ and was disappointed in the performance of the receiver.

[@glynnhm0lsg308]

Hate doing windings on builds my weak spot

[@laseraddict777]

Great video, Kevin. Looking forward to your next upload using the QCX in QSOs on the air. A nifty and amazing little rig. Ordered mine for 20 meters. 72's, de Rick, W B 3 B I Q.

[@jjl6519]

Great video, thanks, I'm going to get one of these..

[@glenngoodale1709]

Nice job Keep the videos coming ....

[@KG5IF]

Kevin, Thanks for the great and very informative video on your little rig. I'm thinking seriously of getting the 40m kit. Following you through the build is very helpful. My only concern is my left hand isn't as stable as it used to be and winding the toriod is daunting. Thanks Rich KG5IF

[@davewinn532]

I would have to take a break after 1 hour. It would be a toss up as to what would go into a spasm first my back or my brain 🧠😎

[@donaldsmith3048]

This reminds me of a Heathkit! Put in resisters, solder,cut off leads. Go to the bathroom, wash your hands get coffee. Put in IC's. LOL, OK they are not that much, but that was a joke someone made about the kits.

[@gonkeyhughes]

Great kevin like it lots from g0myd uk Love your channel 73 How is the day job going kevin are you settleing ok now feeling more at home there hope so.

[@bmmrrr]

bravo

[@QRPp_Radio]

Nice video but I guess you should probably invest in a "fine-bit temperature-controlled iron" instead of that 60's "static-delivery" device!

[@loughkb]

Gotta make do with what I have, still broke and just trying to get by. (I didn't buy the kit, Hans sent me one for review). I can dial the iron back though, kzbin.info/www/bejne/m6HEpJWmbNqIjZI

[@VASGENR6DJF]

cool

[@dl8cy]

awesome work 73 de DL8CY

[@kalibri.tusoer]

Класс сделал мощно работает даже на sdr слышно

[@trig6712]

Excellent many thanks Kevin I would need new eyes Hi GM4NNC

[@mikem8497]

QRP is the biggest waste of money. It is difficult making contacts with QRO with the way the sun is right now.

[@loughkb]

Operating methodology needs to be a little different. I've made many many contacts with low power. The challenge of it is the drama that makes the game fun. Answer calls rather than just calling CQ, and focus on the strong stations. If you can hear them well, you've got a better chance of them hearing you. Also, antenna efficiency is very important. A compromise antenna, like a shortened antenna tuned for a lower band, or a heavily loaded vertical like an outbacker, would be a very poor choice for QRP since much of the power is lost rather than radiated. There's a higher level of precision require for the sport of QRP. It's not for everyone.

[@warplanner8852]

..I would add to Kevin's answer by saying a lot of us also like building - whether it's from scratch or kits. Admittedly, we with "collections" of radios don't use all of them all the time but they are like our "children". Also, it's kind of strange but sometimes a kit you built a while ago might fit a certain set of circumstances (i.e., portable operating versus a Himalayan ascent with austere weight restrictions) and during your session or contest or whatever the little beast hits it out of the park! It's a thrill that one cannot equal with a rig you just wrote a check for!