开云体育

On the QMX rev.2 PCB, it appears that the values of C516 and C525 are swapped between the schematic and the manual. I have run simulations and the values in the schematic seem to be better. What do

You can adjust input gain in the terminal configuration menus. 73 -- David Thomas M0OOR

?? I agree! -- 73, Barb

ROFL... and we can celebrate this fine Tuesday with one less mystery to worry about! 73 Hans G0UPL http://qrp-labs.com https://www.buymeacoffee.com/g0upl

I have used numerous ProgRock2's without any problems -- I install them in old receivers and transmitters to replace faulty/drifted crystal-based heterodyne oscillators.? What are you trying to do

Did you made the output transformer in the WSTS style? 73, Ludwig

Hi Nate From Material 17 I used the size 30 (T30-17). Validation by using T37-10 showed two things: 1. My setup brought probably to high values for L. 2. Despite the deviance (see No 1) the AL of the

You are right Hans! I forgot to mention the most important point! I lower voltage to 5V! Getting old!! Sorry for the snafu! -- 73, Barb

Hello Barb The maximum power dissipation of a BS170 according to the ON Semi datasheet (these are the devices we supply) is 0.83 Watts. If a QCX was producing 5W output at 60% efficiency the heat

Hans, I have QCX V1 and I adapted for usdx and used it with 1x BS170 without any problems many months. The PA efficiency is 60 to 70% which does not create significant excess heat. Actually that QCX

Wrongly wound SWR transformer? [email protected]> wrote:

Abbott & Costello did a great variation on it using "Susquehanna Hat Company" as the trigger phrase. https://www.youtube.com/watch?v=EJxLDdIVX6g

I've got a homebrew QRP power meter (photo of schematic) and it showed 17.7v (+3w) in my DVM.? That's quite a bit more than <.5w!? I'm gonna go back and reflow the toroids and transformers.? Maybe

Hi Barb No... all you do then is fry the BS170. The point of multiple BS170's is less about reducing the effective switch "on" resistance due to paralleling multiple devices. It's more to do with the

Barb, I wonder. I seem to remember that essentially the paralleled devices share the load. That has been mentioned with the U3S. Would just one be overloaded? In any case if the power was reduced to

The easiest mod is to remove 2xBS170 and run on one BS170. QCX will be in QRPp range now with this mod. -- 73, Barb

Hello Chris I didn't have any plans for such a thing... the LCD_LED line is not connected to a Timer PWM output. Which makes it harder (not impossible); PWM'ing 10mA of LED would also inflict a

Question for Hans, are there any plans to be able to control the LCD display brightness in software?? Superficially it seems easy to drive the LCD_LED line with a PWM output which can be adjusted in

I have the same problem with a V2 QMX that affects both left and right encoders.? When turning the left encoder the volume level sometimes jumps many steps.? With the right encoder I have the issue

It also has the potential to be wildly misleading. 10dB may be one thing but if you go much beyond that, you will *think* you are really transmitting a certain amount of power, being your produced