QRPLabs@groups.io

Re: QDX Deaf with high current. #qdx

Thanks for that Dave and Pim, it confirms to me there is more than build issues here. I see the same interference on well proven analogue psu or battery, regardless of PC used or USB lead etc etc. My

By KEN G4APB · #90021 ·

Re: QDX smoked - what to test #qdx

The QDX responds to CAT control via both the terminal program and WSJTX. LED lights as expected (including the "firmware update mode" when disconnect / apply power quickly.) Audio filter sweeps are

By jasongilroy@... · #90020 ·

Re: QDX smoked - what to test #qdx

Jason, Have you tried to connect to the terminal program on a PC? It would be worth a quick test to see if the QDX is responding to the USB poll at startup. Sorry to read the data so far. On the

By Evan Hand · #90019 ·

Re: QDX Deaf with high current. #qdx

Ken, When I say mic input I actually do mean the QDX Transceiver input, sorry for the misleading terminology. Yes, I do see multiple interference bands on the waterfall compared to a similar setup

By Dave, M0OOR · #90018 ·

Re: QDX Deaf with high current. #qdx

Hi Ron, I did not intend to mention IC5. So far I've found that IC9 pin 5 is at ground level and it should not. It should be at about mid-rail since it's getting ~ 2,5 V from the VCOMR pin of the ADC.

By Pim Niessen · #90017 ·

Get that 5 watts at 9 volts

Use the MFJ 259 series Analyzer to get lowest SWR. Connect antenna to analyzer. Look at the R and X reading. R needs to be near 50-52 ohms, X around 0 to 5. Remember exactly what you did to get these

By Don DeGregori · #90016 ·

Re: QDX Deaf with high current. #qdx

Hi Pim. IC5 is a quad AND gate. If one input is low the resulting output should be low (not Hi). On 5B, inputs are pins 4 and 5 and the output is pin 6 (not 7). Pin 7 is the ground lead for the chip.

By Ronald Taylor · #90015 ·

Re: Issues with QDX after the build #qdx

For soldering magnet wire, I purchased one of these tools: https://www.amazon.com/gp/product/B003RWS8XE/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 to pre-scrape the enamel from the wire before

By Ron, N6YWU · #90014 ·

Re: Raspberry Pi #ras_pi_4 #wsjt-x

When running my Pi 4 from a user account, I had to: sudo adduser <my_user_account_name> audio and sudo adduser <my_user_account_name> dialout before I could connect to my QDX.

By Ron, N6YWU · #90013 ·

Re: QDX smoked - what to test #qdx

Thanks for the suggestions. It sounds like I am hosed. IC1 is showing 5V input and 3.3V output. I didn't dare to try to measure voltage on IC8, but I do have continuity from the 3.3V rail to a

By jasongilroy@... · #90012 ·

Re: QDX Deaf with high current. #qdx

Mmm, it appears I got something quite similar after finishing the build today. QDX build for 12V, firmware 1.04 . - Current consumption: 173 mA - Low audio level in WSJTX, only ~ 10 dB above

By Pim Niessen · #90011 ·

Re: BS170 MOSFETS

On Mon, Aug 1, 2022 at 04:23 PM, Andy G0FTD wrote: On Mon, Aug 1, 2022 at 03:52 PM, John Rabson wrote: I seem to recall a question in my IEE (1966?) fiinals which asked me to outline the design of a

By Da Amazin' man G0FTD · #90010 ·

Re: QCX Good news

Thanks Dan! 73 Hans G0UPL http://qrp-labs.com https://www.buymeacoffee.com/g0upl

By Hans Summers · #90009 ·

Re: QDX Deaf with high current. #qdx

Dave, you seem to be getting Exactly the same results as me. rx current 180mA, low audio out (btw, mic input is wrong input for wsjt-x - select qdx ip and op), poor LSB separation. When you have

By KEN G4APB · #90008 ·

Re: Issues with QDX after the build #qdx

I personally have not had good success with the burning the insulation off method. I find I have much better results using an Exacto blade to scrape off the enamel from magnet wire. Yes it's more time

By KC9REN · #90007 ·

Re: QDX Deaf with high current. #qdx

By the way, my current draw readings are from my bench power supply so may not be that accurate. After running the radio for a couple of hours and making several QSO's, nothing got too hot (apart from

By Dave, M0OOR · #90006 ·

Re: QDX Deaf with high current. #qdx

** Update ** In the interests of sharing my findings, I have now got it working. What I have done: - Reworked L12 - this improved things greatly ( I must have had a fault there). - Reflowed joints on

By Dave, M0OOR · #90005 ·

Re: While poking around on the QRP=Labs website this morning ...

By @BruceUK · #90004 ·

Re: While poking around on the QRP=Labs website this morning ...

My experience is on QCX+ rather than QDX but for what its worth : Having put a very very light smear of heatsink compound (standard white silicone/zinc stuff) on the flat faces that get screwed to

By @BruceUK · #90003 ·

Re: QDX Deaf with high current. #qdx

Mike Ah yes! I too remember now. Hans did say somewhere that the different audio ICs in the v3 took more current. If Dave's measurement is accurate his is taking a little more than normal. But not a

By Alan G4ZFQ · #90002 ·

Messages