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QDX On The Air

 

As noted in my other thread, the QDX is on the air! I built it for 12V operation, which means that T1 is wound for with two turns on the secondary instead of 3.?

I powered up the radio with my 12 V 8xAA pack and all was fine. I updated the firmware (Sooooo easy) and then configured WSJT-X for a test on 40 meters. I answered a CQ and?immediately had a QSO on the first try, and in fact one of the first transmissions of the radio ever. Extremely impressive. Output? 3 W!?

I then hooked it up to my 14V bench supply and it's putting out 6W. I think this is fine, we'll see. I can probably turn my supply down to 13.5 V if needed.

Pictures: Left, 6w Output, Right: JS8Call on 40M


Nice job on this, Hans. She's a beauty! And even if I only ever use it for 40 and 20 M, I got my money's worth many times over. This is already outperforming my BITX40 by a?long shot.

--
Ryan Flowers - W7RLF
 

Hi Ryan,

You have a nice signal in Boise this evening on 40m as seen on JS8Call, if that is your QDX transmitting. Have fun with it.

73,
Gregg W7GRM

On Sun, Oct 31, 2021 at 7:42 PM Ryan Flowers <geocrasher@...> wrote:
As noted in my other thread, the QDX is on the air! I built it for 12V operation, which means that T1 is wound for with two turns on the secondary instead of 3.?

I powered up the radio with my 12 V 8xAA pack and all was fine. I updated the firmware (Sooooo easy) and then configured WSJT-X for a test on 40 meters. I answered a CQ and?immediately had a QSO on the first try, and in fact one of the first transmissions of the radio ever. Extremely impressive. Output? 3 W!?

I then hooked it up to my 14V bench supply and it's putting out 6W. I think this is fine, we'll see. I can probably turn my supply down to 13.5 V if needed.

Pictures: Left, 6w Output, Right: JS8Call on 40M


Nice job on this, Hans. She's a beauty! And even if I only ever use it for 40 and 20 M, I got my money's worth many times over. This is already outperforming my BITX40 by a?long shot.

--
Ryan Flowers - W7RLF
 

Thanks Gregg, it sure is! Now I can put my BITX40 aside and start refining it and get it into a case since I'm not using it every day :)?

--
Ryan Flowers - W7RLF
 

Hi Ryan,

Well, congratulations. I'm looking forward?to receiving?mine (mine hasn't shipped yet). You were -04dB in Boise.

73,
Gregg W7GRM

On Sun, Oct 31, 2021 at 7:57 PM Ryan Flowers <geocrasher@...> wrote:
Thanks Gregg, it sure is! Now I can put my BITX40 aside and start refining it and get it into a case since I'm not using it every day :)?

--
Ryan Flowers - W7RLF
 

Cool.? Makes me wonder if I should not have done a 3:2 instead but eventually I want to use it with batteries and a switching buck converter for field use, so I am going to struggle with 9V.?

I have a supply or two that can do it I think, and if not I am planning on a small LM317 regulator with a PNP wraparound current boost as a bench power control (hardware limited to about 10v) anyway for home use and for output power control.??

Hopefully next weekend I can get back to it, but it's encouraging to hear I think the first success report.? Glad to hear the success story. As I thought, I didn't have time to even touch it today.? I am maybe 90 minutes away from completing the kit.?

Fred W0FMS?


On Sun, Oct 31, 2021, 7:08 PM Gregg Myers <gregg.w7grm@...> wrote:
Hi Ryan,

Well, congratulations. I'm looking forward?to receiving?mine (mine hasn't shipped yet). You were -04dB in Boise.

73,
Gregg W7GRM

On Sun, Oct 31, 2021 at 7:57 PM Ryan Flowers <geocrasher@...> wrote:
Thanks Gregg, it sure is! Now I can put my BITX40 aside and start refining it and get it into a case since I'm not using it every day :)?

--
Ryan Flowers - W7RLF

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