Too keep is short, QDX Rev 3 with the 1.04 firmware is providing 5 volts to the ring of the PTT cable, but not triggering the QRP Labs’ 50w Amp. What should I be checking? more details: - QDX wired fo

As I am waiting for my QDX to arrive here, I am thinking of how to replace the 80 m band with one or two higher bands. I think 17 m should be straight-forward. Since the transmitter's LP-filter for 30

Anyone else have this problem? The operating manual says’ The following keys are used in the Transmitter test application: + increases the band - decreases the band p Enable PTT (Highlights in YELLOW)

Hey gang. Received my assembled QDX today...Thanks Mark ! OK, so the receiver is plenty hot...I'm playing on 40m first. When I attempt to transmit - either by the 'Tune' button or by actually calling

Finishing up my "Manual Days" QRP Chinese Antenna Tuner and decided better artwork just had to happen! I watched way too many YouTube videos on ways to label front panels. I discovered there is a "bra

Hello Hans and all, I built the QRP Labs Si5351A VFO/Signal Generator QCU Ver. 4 for use in a Kenwood TS-520SE, for replacing the Kenwood VFO that lacks frequency stability. I have a single 60 meter L

Greetings all, I've no wish to stir up the debate about which supply voltage QDXs should be built for, but in reading the manual, I saw where it says that the power slider in WSJT-X has no effect on t

Yesterday evening I finished building my QDX and was quite proud of myself, for it was the first 'real' soldering project in ~8 years. I already realized how old I have become when I needed a 20x micr

I am thinking of buying the VFO/Signal Generator kit but i am concerned about the unbuffered Si5351A output be output at the front panel. I intend to drive a 50 ohm coax cable of 3 feet. Therefore doe

Just finished the QDX V2 and its working fine on a WIN10 and a LINUX box, but despite installing, and re-installing, the relevant drivers for WIN7 it refuses to be recognised. I've read all the other

Hi Folks, is there anyone here who is thinking about adding a bluetooth interface for QDX? This could improve the portability of it. QDX could be deployed very close to the antenna with some battery a

I recently built the QCX-mini 40m kit. Being new to kit building, I couldn’t be more thrilled that it works! However, I applied too much heat soldering the BNC female connector. The center pin comes l

Thanks for letting me into the group @Hans. I was the source of the JS8 message reminding you to approve new members. ;7) My QDX V3a is more or less working. I need to adjust L12 to resonate at the co

I have built my QDX all is working fine. But it taking 150 mA on RX. The spec said 100 mA. Philip G7JUR

I have the QDX from last December (rev 2 I think?). Somehow I managed to show up on PSK reporter for the nearest monitoring stations on my first try, but nobody was responding to my CQ or acknowledgin

Rookie kit builder working on building the 50W amp (rev 2). I'm trying to figure out if I screwed up or I'm seeing something "normal" once I put a transformer in the circuit. I wound and installed bif

Hi all, for those who are as eager as me to get an extra serial monitoring port for the QDX in a future firmware release, here is all my humble technological knowledge allows me to contribute to this

Hans, I've been wondering this for a while. What would you consider "really badly mismatched" with respect to the QDX SWR? 3:1? 2:1? 1.5:1? I have a WSPRlite with, I assume, no VSWR protection. They r

Hi, I am, using the QRP Labs 50W C class amplifier with QDX transceiver. It is doing a good job. When I measured the S21 parameter I have noticed quite a difference in gain. The slope is from 16 dB to

Hello all, I'm curious about the general consensus for setting receive audio levels on the QDX. I've been using WSJT-X mainly in FT8 and FT4 with an occasional check in WSPR. I like the fact that QDX