Some RF problems in the shack that do not yield to the usual ferrite chokes, grounding, etc. Would it make sense to put bypass capacitors on key, phone, power leads? If so, what value? I may add a

The shotgun approach is often even used in industry. Depends if labor is more expensive than parts or not. It does not matter if you trouble shot or not if the final product passes all tests. So

But that's not troubleshooting... that's loading up the parts-cannon and firing at point-blank range. Yes, the radio gets repaired (maybe) but no troubleshooting has been done and that method is ripe

Nice thread here with wise advice. Over the years, to this will add as mentioned below with familiarizing parts and learning the schematic, a free step, for someone reading this who is about to start

Oh! dear, I need to buy some more tools :-)

Dave, Seems to me several have almost been repaired like that. A scope has been bypassed by guessing what IC(s) to replace. 73 Alan G4ZFQ

Howard, I agree with your comments, however, unfortunately by the time the new builder gets to the advice/help provided here it is often times too late. He has already jumped in above his

Leo Sorry, I think I got close referencing you to " it usually turns out to be OUR MISTAKE, " 73 Alan G4ZFQ

Sorry Alan, I thought the nature of the testing and that I'd mentioned the seating of the ATmega inferred that I'd read around the problem. Not to worry - the link is there for others. Thanks N3MNT -

Ted, you came up with the solution, I remembered being concern about a short to the display "tab" so at first I tried to bend it lower, did not like that so I used side cut to cut off some the tab

Hi again John I just dug one of these displays out of a very deep drawer. The highlighted clips hold the whole display together, when I have messed with these in the past, problems such as yours begin

Check to make sure the connections between the front panel and the main board are correct Looks like the connector may be misaligned. Also check IC4 orientation. Photos may help.

I also had this problem recently with a homemade key and a likely-mismatched antenna. I'm still experimenting, but it doesn't happen with a dummy load.

Perhaps a solution to using a low ESR LiPo battery is to place a low value resistance in series. Yes, the energy loss goes against everything I believe in my bones, but it might prevent the sudden

I agree and it's not elitist at all IMO. I have built a lot of kits over the years including an Elecraft K2/100 ad I would not call the QCX series a beginners kit at all. It's a great design and

Leo, OK but you did not say you looked there. It is essential that that stage is reached. Nothing will work until you have the correct display. There must be something wrong in that little

I do hope I did not come across as elitist, it certainly was not my intension, mearly to offer some advice to newbies, to avoid too much disappointment when things don’t work. Whilst there are lots

Hi Fredi, Just in case you didn't know, a fully charged 4S lipo is about 16.8 volts. A QCX(+) would usually survive it, but not the mini. I'm sure you will get some good help on how to proceed. --

this is one problem that anyone using a lipo to power ANYTHING, is there ability to supply ridiculous amounts of energy in a very short time. LiPo’s do not take prisoners. Dig out the old soldering

Thanks. Naturally I have read the troubleshooting sections including the page you linked, which is why I included a reasonably exhaustive list of actions and measurements taken. Unfortunately the