There are many proponents of the concept of building your very own homebrew station frequently involving more than a simple CW transceiver. Often the discussion will start off by saying this is how the hobby started, or a true ham is more than an appliance operator. Still others will say that it is through the understanding of the form, fit and function of each and every component will you then and only then appreciate fully our hobby.
Today I want to explore the many reasons why you should NOT build your own rig. This seems strange coming from me; but I do want to relate some personal experiences that support this argument.
My published works both formally via mediums such as QRP Quarterly and the GQRP SPRAT and Hot Iron and on my websites, you tube videos and N6QW blog contains about three dozen transceiver projects with about 98% being SSB and the other 2% --you know the other mode CW.
This sharing of knowledge has frequently generated lots of email and lots of questions. Quite often the questions reflect the real desire to homebrew a rig but too often that the prospective homebrewer lacks the gravitas to pull it off. I respectfully try to answer all questions without being derisive or resorting to comments such as "Stop you won't make it."
I have been keeping a collective of the reasons why these individuals should not attempt building a homebrew rig and this listing may serve as a roadmap of what needs to have the box checked in order to be successful. Basically you can group the reasons into lumps such as 1) Basic electronics knowledge 2) Lack of experience 3) Lack of test gear 4) Unfamiliarity with the new technologies and 5) A large Junk Box
- Building electronic circuits requires some basic knowledge such as understanding Ohms Law, LC Circuits, DC versus AC circuits, and all important, mathematics beyond addition and subtraction. Resistors in parallel are product over the sum. Now we have multiplication and division. Capacitors in series follow the same construct. Oh and which is the collector, base and emitter pins. Did I also mention you must know how to read schematics; and being able to work with LT Spice is a must!
- It would be something short of a miracle to successfully build one of my SSB transceivers without having previously built something. A SSB Transceiver is not a first time project! There is much tribal knowledge to building RF circuits without having them oscillate, or be subject to unwanted feedback. Often "newbies" think they can homebrew a crystal filter simply by purchasing 5 crystals and you are done. You may need to buy 30 such crystals and then proceed down the path of "black art" to finally end up with a workable filter. Again a miracle complete with a star on the horizon will not net a good filter without some large experimentation being involved.
- A person once shared that he built a one transistor CW transmitter and couldn't tell if it worked as the only receiver he had was a crystal set. He did not own a VOM, did not have a SWR Bridge nor did not know what a RF probe was. Dabbling with electronics today means some basic test gear like a Digital VOM, LC Meter, Digital Storage Oscilloscope, SWR Bridge, Dummy Load and test oscillators. Yes some are big ticket items but inexpensive high quality analog Scopes can be had at very reasonable prices. You also need a linear or high quality switching power supply --forget the WalWarts!
- I can build a digital VFO with an Arduino, Si5351, and a Color TFT Display for about $20. BUT unless you know how to program the Arduino and how to connect up the Si5351 with Color TFT --all you have done is spent $20. Too many times I get an email --"your code doesn't work and when I hooked up everything nothing shows on the screen". Invariably the person ignored the documentation and simply counted the pins on the Arduino --- D3 is not third pin on the Arduino (it is actually the 6th pin). That follows that D12 is actually the 15th pin. They ignored the many project write ups that discuss the IDE being used and the need for included files. In short they never invested the time to go through the Hello World tutorial or LED On LED Off exercise. Their 1st experience should not be is a band switching, two VFO sketch -- not for the faint of heart. Purposefully I put splash screens in my code as an irritant so that in time you get tired of seeing Seabee's Can Do which will force the user to change the code. Also noteworthy get used to surface mount parts.
- I buy parts in bulk and have a large junk box -- you can buy 10 resistors for $1 or 100 for $4. There are many common value resistors that are used over and over. Values like 100 Ohms, 1K Ohms and 10 Ohms. A bit of judicious buying can net a nice junk box. A $20 bill will get you 500 resistors of 5 most common values. The same applies to capacitors -- the two most common values are 10nF and 100nF -- same deal only a bit more expensive as these are typically 100 pieces for $6 or $7. But unless you have been stocking up; buying parts in small quantities will make the project cost an arm and a leg.
There are some other issues such has having a few good tools including a temperature controlled soldering iron with a fine tip so you can work with surface mount parts and an electric drill ( Li Po battery powered are nice). A variety of good quality screw drivers and needle nose pliers along with some "nippers" and an Excelite socket set round out the mix.
There are many other tools and techniques like bench vises, metal benders, Drill Presses, CNC mills and 3D Printers round out some ham shops.
Above all is the time investment to learn about the hobby, how to do things (you tube) and you will have to invest in buying reference materials. Typically EMRFD is suggested as a reference document and I can tell you my copy is doing yeoman's service as a bookend. Harder to find is Solid State Design for the Radio Amateur -- more useful. You must set up your computer so you can find stuff. You must also tune into blogs and You tube videos from Charlie ZL2CTM and DuWayne, KV4QB and of course N2CQR's SolderSmoke Blog. That is a big time sinkhole to read all of that stuff.
So why would you even think of homebrewing a rig when you can buy rigs that almost make you feel like you are homebrewing a rig as you do have to do some work to get it on the air -- but that is mostly mechanical stuff.
- Ashar Farhan's Bitx and uBitx kits get you there ranging in price from $60 to $140. (Mostly assembled & tested)
- Hans Summers QCX and QSX kits in the same range gets you there for about the same $$$
The value of these two kit suppliers is that they are proven kits and have web reflectors for help. Scratch building a rig and not having in depth knowledge or the proper tools or test gear ties both arms behind your back and there is a high probability of failure.
So don't even think about homebrewing a rig unless you can check off all of the boxes. I have 60+ years doing this and might add -- 60 cumulative years not one year 60 times over. Thus I can build rigs because I can and should add every once in awhile even I end up with smoked parts where a rig once stood.
So if you want to get on the air and make contacts, buy it don't build it. (unless you follow what you need to do).,
73's
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