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Thanks to all who replied to my earlier post, with all comments pointing to T1. I completely unsoldered it and removed all the wires, and re-wound it and with exceptional care, reinstalled it. My desoldering technique needs work, and I lifted a trace or two, so I had to replace those traces with point-to-point wiring. Receives, though rather deaf, receives on both sidebands (USB, LSB), and transmitter works well with 5w at 12 volts from my little 8ah 12v battery (verified by listening on my Yaesu). When I try to align C1, best results with plates completely unmeshed, so removed some turns from T1 per instructions, C1 becomes unresponsive. IQ balance control and Hi/Lo have zero effect no matter what I do.?

So, I am officially giving this up as a bad job. Fortunately I have another QCX coming, #1200. I will install T1 FIRST! I will wind the windings with alternate colors of wire (green vs golden) so I can absolutely tell them apart! (The 40m version of T1 gets very full.) In the meantime, #663 goes on the scrap heap.

73 to the group!
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Dave Casler
KE?OG
Colorado, USA

www.YouTube.com/davidcasler

Hi Dave,

Well I hope that scrap heap is in your house, as you may find it very useful to replace parts of your 2nd QCX with e.g. if you blow a component etc. Wish you good luck with the 2nd build, with all the practice you've had with T1 no doubt it'll go better!

73 de Lou

If the RX is not salvageable, #663 will make a great WSPR 'beacon' transmitter if that mode is part of your sphere of interest.

73, Bob? ZL1RS

Hi Bob,

Thanks for the suggestion. I currently have a 20m Ultimate3 QRSS/WSPR beacon on all the time. Right now I'm using an indoor loop antenna, but it still gets out all over North America!

73, Dave
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Dave Casler
KE?OG
Colorado, USA

www.YouTube.com/davidcasler

You?do know that I'm the USA, FCC rules do not allow the running of a 20M beacon "all the time", right? Beacons below 10M must be attended when in operation. See part 97.203

Hi Dave

I can feel with you, because I am exactly in the same situation like you with a QCX for 60m, #741.? The only difference to your description is that I could successfully adjust the number of turns of S3 winding of T1? so that the C1 came nicely into tuning range without reaching minimum or maximum capacity. I had to remove 3 of the 46 turns (60m red core)? that the table is calling for (I thought taking off more turns if needed would be easier than addings turns that I have removed too much (the handbook suggests to take off 5 turns), With other words, I can very well peak the BP filter with C1.

However anything having to do with I/Q adjustment does not work. The I/Q balun pot R27 does have an effect on the ampltude of the measured test signal, however the "minimum" ist at or beyond (?) the extreme CCW stop of the multiturn pot. I would not call that a true minimum adjustment. There is little to no effect on the displayed amplitude for the phase shift low or phase shift high adjustments with R24 and R17.? The receiver does work a bit, I even was able to make a QSO with a sttion 200 miles away using 5m of wire, but I can't judge sensitivity and due to the lack of stations on 60m I can also not say if there is any sideband attuniation or not. THe TX is working quite well, output is 3.5W on 60m at 14.2 V at the input terminal.

I also did not trust my T1 fabrication and like you I completly rewound T1 (I only lost one solder lug and 1/8" of a copper trace while trying to clear the PCB holes from solder) and I am now pretty sure that all my 4 windings on T1 are ok and go into the right holes.I mean the sense of the windings is right, the number of turns is right, but redoing T1 did not change? anything. I have no idea what I else I might check.

Like you I have another QCX that I can assemble soon. Today I received my #791 40m QCX kit where it is somewhat easier to fit all the required turns onto T1. However my enthusiasm has been greatly reduced, the QCX kit seems to be not as easyly or reliably reproduceable like I had hope for initially.?

By the way,? I also have a U3S working here which is working quite well. Using it with a small amplifier yields nice WSPR reports on 40 and 30m, but even on 60m I receive reports from an EA8 station? 2200 miles away with 14 watts at a 5m wire. Could not test WSPR with the QCX? as it does not work reliably in WSPR with firmware version 1.0b. Still have to find out how to upgrade to 1.0c that might work better.

So good luck and tell me if and when you found something that makes the thing work.

73 from Cologne Germany

Klaus
DL2QB / WN2Z

Hi Klaus,

Sorry to? hear you're having problems with your QCX too. I have been tracing circuits to see if there is possibly something else wrong beside T1. I plan to inject a small signal right into T1 to see where the tank circuit actually resonates, and adjust from there. I should also be able to tell if the inputs to the quadrature sampling detector are actually 180 degrees apart. I figure if I break something it won't matter.

73 from Colorado, USA
Dave, KE?OG
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Dave Casler
KE?OG
Colorado, USA

www.YouTube.com/davidcasler

I found that when doing the IQ adjustments with the 3 potmeters you have to open up the volume control in order to get any reading at all. So if you have turned down your volume completely that might explain low/no reading
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Regards/73,

Enno, PF5X

Exactly, and I think the instructions warn of this, you have to set the volume at a point for the reading to be around the middle so that your adjustments will make sense, and you may in fact vary it again, what matters is achieving the dip or on the BPF the peak. I think at first I also did not understand the digit in the top right, maybe it wasn't too clear to me when I read the instructions, so I wonder if some others miss than and misunderstand the rise/fall of the bars if they are not also watching the top right digit!?