Finally got the Softrock RX TX kit assembled. Everything seems to be working at this point. I will have to say again, that I am very impressed with the SDR receiver in the Softrock RX TX. Frankly, when couple with a good computer sound card, it is shockingly good for a less than $75 SDR radio kit. I would have to say the Softrock RX TX is an outstanding bargain for a QRP SDR Radio. The only catch is that you have to build it. How hard is it to build, well that depends on you. At any skill level I would say that it is a challenge. The trick is to have the proper tools as I mentioned in my previous post. A temperature controlled soldering station, a magnifying lamp, and a set of non-magnetic angled tweezers are essential. This best way to approach this kit is to use the builders notes from WB5RVZ. I found the instructions to be spot on with the exception of the orientation of the very last smt capacitor C68 in the Driver/PA stage. Fortunately most of the kit is “through the hole components”, which are very easy to install. Also, the part count is not that large for the kit. Where the challenge come in is with mounting the smt capacitors, the very small ICs, and winding the coils. If you are going to run into trouble, it will probably be in these areas.
My problems came in with the op amps for both the RX and TX section. Invariably, even though I thought I did a great job of getting the chips soldered in, I noticed I was getting AC hum on both receive and transmit. Under closer inspection with the giant magnifying glass / lamp I saw a couple chip legs that looked fishy. After a quick touch up with the soldering iron, all was well. I haven’t had much time to put the rig on the air, but I will report back when I do. I decided to order an enclosure from KM5H to give it a more finished appearance as well as protect it. I would say that if you have the time and skill to put one of these together, the Softrock RX TX is a tremendous ham radio value for under $75 dollars.