I am building the Beaconator ][ based on my success of the 40th TT2 transmitter. My original on 40M was modified to increase the power with a metal transistor body & heatsink which netted around 850mw output. I didn't have a QSO with it yet as there is much QRN at the RV park and 40M is done for the day by the time I get my wife back from Physical Therapy, plus the skeeters here kill you after 4 pm. I went to the WMA to do a POTA activation, but they close 30min after sunset & there is a 1000x more skeeter supply.
I purchased a 2nd 40th TT2 and put it on 30M, I get a decent 800mw from it. I may use it at an activation very soon should my wife's PT and my father-in-law's nursing home rehab visits give me a free morning. My biggest issue is my arthritis with using a straight key. QRPp POTA requires calling CQ endless times before you get your first response and then they trickle in from there. I have a Pico Keyer Plus on order.
Seeing the Beaconator ][ has similar circuits plus a Pico Keyer built-in, and it has band modules that also require swapping out cap Cx and L1 inductor with the band module change. I am waiting for my 17M parts to come, but I built up the band modules I had parts for (some robbing of other Tuna kits of course, LOL) and did the power mod to change the final to metal with heatsink. These are my results.
80M - Not built yet.
40M - 530mw, very good CW signal.
30M - 590mw, very good CW signal.
20M - 424mw, very good CW signal.
17M - Not built yet. 18.096MHz crystal.
10M - 092mw, good to very good CW signal.
10M was quite the challenge as it wasn't originally intended on the original design. I used the chart from the Super Tuna band modules to wind two 37-6 toroids to get the 200uH and 270uH inductors, plus scrounged the caps required. Also, Inductor L1 and cap Cx had to be determined. I noticed that the schematic specified that L1 be 10x the values of L2 and L3. Since I was using values from another chart I did not have any 2uH or 2.7uH values for L1. I first tried a 3uH Inductor and the power output was very low. I then tried a 1uH Inductor for L1 and the Output power was 134mw, but the signal had a large chirp on it. I then put two 1uH inductors in series to get 2uH and the signal cleaned up 95-98%, maybe a 2.2uH would be perfect? The power output dropped to 85mw and then I experimented with various caps on Cx from 27pf up to 82pf. The 28.060MHz crystal is oscillating 5.5Khz low. When I choose anything from 39pf to 27pf, the frequency does not pull as low, but the Tuna Helper does not switch the T/R relay even though the waveform sounds great in the receiver. When I choose anything from 47pf up to 82pf, the T/R relay works great on the Tuna Helper, but the transistor frequency pulls further down in freq AND the power output radically starts dropping off. When 10M is open, 92mw will work great with a good antenna, which isn't usually what a POTA antenna setup consists of, but I am willing to give it a go with a dipole kit I have not built yet, I was just waiting to know what band to build it for.
The weird part? I tried three 28.060MHz crystals. Two of them resonated at 28.055MHz and the third 28.095MHz (Right in the Digital portion of the band)!!! When I measured the power output, I got 695mw!!!!!! What?!? The signal though, had a large chirp on it from the limitation in L1. It is a Raltron brand and I have no idea what characteristics are different about it other than I am setting this Red Headed stepchild aside to deal with later.
After I get my band modules done, I will build up my Sea Sprite from last spring that I could not get to during the Buildathon and then I will commence troubleshooting my Super Tuna ][+ which is built, but has no oscillator signal. I see the red LED from the keying circuit, I just have to find that wrong or backward part that is haunting my power-up tests.
Cheers,
Davey --KU9L
David Knapp