I bought the R2 receiver and T2 transmitter kits in 1994 but left them unbuilt. In 2012, I wanted to get on the air with a homebuilt radio faster than I could if I designed one from scratch, so it was time to build the kits. I am integrating them into an 3 MHz – 30 MHz (HF) transceiver for SSB and digital modes. The initial version will be single-band, but since I cannot decide which single band I want, I plan to convert it into a multiple-band receiver.
Features
- R2 single-signal direct-conversion receiver board
- T2 phasing-type single sideband transmitter
- Si570-based local oscillator
- Salvaged case
Posts
- Building a KK7B T2 phasing transmitter (18-Dec-2011)
- Building a KK7B R2 phasing receiver (27-Jan- 2012)
- R2 receiver update: Time for new electrolytic capacitors (24-Feb-2012)
- KK7B R2 receiver: lifted pads, a scorched board, and it works anyway (24-Mar-2012)
- An enclosure for the R2/T2 transceiver (21-Jun-2012)
- Going Forth, or maybe not. (22-Sep-2012)
- An Si570 VFO for the R2/T2 transceiver project (14-Oct-2012)
- Some thoughts on the K5BCQ Si570 signal source (18-Nov-2012)
I had built the R2 and T2 back when they first were out but I never have powered them up. I was getting closer at one point when I had an I/Q VFO project which I thought would be good to use with them.
I just read your article about the new electrolytic caps. I’ll have to keep that in mind when I finally get around to integrating things again. I think I can afford the $2.85 or so for newer better caps!
73,
Mark, NK8Q
P.S. I studied Electrical Engineering under KK7B at Michigan Technological University in the late ’80’s. What a great professor and ham!
I was wondering if you have any ideas or plans for a 2 meter and 440 dual band home brew transceiver or how hard it would be for a novice to design and build one.
I’m sorry, but I don’t have plans for anything but what’s up here. A dual-band 2m/70cm radio gets a bit complicated because the frequency is high enough that your assembly technique starts to really matter. If you’re a beginner, I’d suggest starting with a kit of some sort. Also, get yourself a copy of Experimental Methods in Radio Design (ARRL Press) and have a look at it. There’s a lot of good stuff in there.
It’s probably been done somewhere; I had a mini R2/T2, lost it several moves back. Plan to re-do these circuits in surface mount. I think 0603 is about as small as I feel comfortable with.
I have an old mini-circuits MIQY-70D, so I’ll design it for a fixed 70MHz IF. Just heterodyne whichever band I want up (or down!) to 70 MHz. I may make the 70 MHz IF somewhat timetable, perhaps 100 kHz wide, like in some old avionics NAV/COMM radios. This way I could use a simple synthesizer with 100 kHz steps.