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Ronald Taylor <wa7gil@...> wrote: I agree. Looking at the schematic of the PA, I'd check Q5. It might have a short-circuit (or near short-circuit) between it's gate and source.

Wilson Little <wilsonlittle66@...> wrote: Did you adjust the bias voltage (R5)? Amp shouldn't be keyed without setting it to minimum (counter-clockwise) first. Fortunately most probably nothing

Were you aware that you can get waterslide decal paper that's printable with an inkjet printer? There's both white background and clear background available. So you can roll your own. 73 Jim N6OTQ

I'm having terrible luck with the waterslide decals, but I've squeezed the tuner into a smaller box.

Ronald, Thank you very much for this communication. Unfortunately, I rush to the next step before receiving. You can see the results…. No so good. But, on a positive note, more things to play with

Good News / Bad News Good news was I found a 100 ohm resistor to tack in parallel with the QDX R10 resistor, and it enabled the QRP Labs’ 50w Amp to turn on. The red TX led might be a little less

Will, your measurements were very thorough. Thank you for those. Those measurements are pointing to some other issue that we aren't yet seeing. You are showing almost the entire 5 volts dropped across

Oh, _that_ kind of dummy load, that everyone else in the known universe calls an attentuator. Makes me wonder if there's some other miscommunication going on here. Which one of those 'dummy loads' do

Please explain about the dummy load being an issue. BTW, this dummy load requires no interconnecting coax- has bnc male on one end, female on the other. My combination dummy load / attenuators consist

The answer is yes. Because you said that with QCX the PTT switching works and because your measurements show that the voltage drop over the 470R in QDX is too much. 73 Bojan S53DZ

Ok, confession time. I am not an electrical engineer. I am a mechanical engineer. This might be important in that my understanding may need corrected by folks who are much more knowledgable. :) First

Hi Charles, Please see the U3S Assembly Manual what to add to the PCB and how to connect things and for the jumpers. At least you will have to insert one BS170 to allow the signal CLK0 to come to the

Ron, of course you are right about the current protection of a BSS84 in the QDX.? It is now about 61mA instead of about 11mA.? But this current limit is used only if one does a short to GND during

Hi Will. Probably best to go ahead with Bojan's suggestion and parallel a 100R across R10 in the QDX to raise the PTT eying voltage. Hope that solves it for you .. .73 ... Ron

And Will, have you measured the voltage over the series of 470R and the red LED? 73 Bojan S53DZ

Hi Will, generally I prefer using the active zero Ohm PTT line, as I said.? And I will do it in due time. 73 Bojan S53DZ

Hi Ron, No I did not do those precise voltage measurements, however I did a simple test when I was first trying to use the QDX PTT to trigger the PA.? I noticed that in that case the power did not go

I measured the voltage at the red TX led on the amp trigger by the QDX. It was only 0.89 volts. The voltage on the red TX led on the amp triggered by the QCX Mini was 1.94 volts. … Now, what is the

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

Hi Bojan. Interestingly, I breadboarded the keying circuit including the Red LED and resistors and there is still something like 3.3 volts available to the gates of the two BS-170 switches in the PTT