I found this at the end of the rx assembly instructions... 15-Sep-2016 Corrected reversed orientation of BPF module in section 6.1 and photo in section 5. 73 Ken G4APB

Steve, sounds like your S2 button is stuck or you have a short circuit across it. Check across it with an ohmeter to see. 73 Ken G4apb

Hi Bill, Hans, thanks for the replies. I was curious of your setup Bill, I expected you to say the opposite! I also run my gps units from their own analogue supplies. I even built my own analogue ‘rf

In the standard configuration described in the assembly manual, the LPF kit inserted on the right (in position 1) is ALWAYS in-circuit and should be the filter for the highest frequency band installed

Hi Bill, do you not suffer interference from the clock/gps combination placed like that? Unfortunately, I get severe ‘pulsing’ broadband interference from the gps data bursts from mine. I started with

Your results will depend on what other losses you have taken out in the CAL. The 4 pole non-50 ohm connections to the filter should NOT be calibrated out if you want a true 'in circuit' reading as the

#filter

Hi Mike, I had the same problem, made it almost impossible to tune across the band. I tried modifiying the unit to be a U3S Rx and ‘potentiometer tune’ method but that still has an unresolved bug - on

Hi Vernon, have you tried measuring the power on the one fitted in position 1 with all other lpfs removed? I have had an issue with two faulty relay switched lpf boards where more than one lpf is in c

Hi Mike, I often run my U3S 4m Tx and Rx system on WSPR but it is a very lonely band as you say. I have managed to boost my OCXO controlled Tx to 1 Watt using a modified QRPlabs '5Watt' PA, and booste

Yes Chip, you will need to programme a second alarm to come on at 8am and go off at 8:01am. You also need to set the sense of the output you use for ‘active low’ to only enable the speaker ‘gnd’ conne

#clock #case #mods

Hi all, this was fixed in version c1.03... ADC now averages 100 samples to reduce noise (for temperature calculation etc) 73 Ken G4APB

#clock

Hi Cathal, the U3S will auto cycle through a maximum of 16x 2minute operational slots in sequence. You have to re--set the default from 3 slots (TxS). You can choose the transmission mode (WSPR) and f

#wspr #firmware #u3s

I used one of the other alarm outputs to control a simple ‘mute’ circuit to stop this tone when the alarm is not sounding. Instead of connecting one side of the loudspeaker to earth, connect it to ano

#clock #case #mods

Ah but Reg, if you are running mW levels and your signal is down in the noise and borderline discernible, then a few more mW might make the difference between a contact/spot and none. You are looking

Hi Giuseppe, the picture you show looks fine, but this assembled board fits INSIDE the external screen, so it cannot touch IC1 unless you have assembled the external screen incorrectly. can you show a

#ocxo

Hi Paul, the red led is across the 5v supply so should come on regardless if the gps is working or not. Have you fitted the leds the correct way round? Have you connected the 4 way connector up backwa

Hi Brian, from your wspr waterfall it shows you have massive frequency shift at the start of transmission. This will prevent any of your transmissions from being decoded. For 6m I found I had to use t

#u3s

Sorry Gilles, got interrupted before I finished...I was going to say for a first start-up of a new gps unit to need to give it a good clear view of the sky to allow a new almanac to download, can take

#gps

Hi Gilles, more info please. Are you getting a lat/long coordinates indication on your U3S? Four stats sounds too low, you should be seeing many more. 73 Ken

#gps

Hi Phil, I have wrestled with these problems too. I found I have to use multiple RX mode 2 minute slots for near continuous receive AND be able to select the correct bpf (not lpf) in a multiband confi