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370 kOhm as in kilo-ohm? That's the opposite of a short. Installed in the circuit, there is about 10k of resistance between the primary and secondary windings of T501 because the primary is connected

A thermal camera is hands down the best way to identify a shorted component. Turn on the power and look for the thing that glows. You can get one that attaches to your phone for about $2-300. A

Well, pulled the finals and still draws 700mA when the left encoder is pushed. It stays there until I kill the power to it. No display backlight. Other things to check? I hate to pull the driver chip

I think that given all of the people experiencing blown components due to power supply issues (including myself), there is a case to be made for a redesign of the power supply. Something like an

Jeffrey, I'll take your word for it. I've blown the finals on the QDX and it was just low power out. I guess the QMX is different. That sure is an easier fix than some other things. I'll just pull

I started building QMX following the instructions carefully. I've been checking the solders in every step. Installed the transformer T501, checking the continuity between the A points were fine as

I picked up a QCX mini, 20 m, revision 1 at a ham fest.? When building I noticed the R46 resistor was badly placed and cracked.? It looks like a factory error when placing the SMD's.? I need a

The Q103 FET was broken In an attempt to move it, 'D403'.? I have several AOD21357 FETs that appear to have virtually identical specifications.? Can they be used as an acceptable substitute for

Finished, in the box and working! -- 73 Karl KI4ZUQ

Yesterday I activated a POTA and took part in the Skeeter Hunt with 10 contacts in 7 States and the RBN reporting me 3750 miles away using my QCX-Mini and a homebrew 20m (46”) Mag mount. My power

Yes. ?That is not unusual for blown finals. ?Try replacing all 4 BS170s. ?Chances are good that will fix it. ?If not it may be the driver IC needs replacement also.

Set the "power" slider in WSJT-X all the way up. In the digital mode the QMX is not modulating SSB. Its doing true FSK, based on the tones on the input. If they're below the threshold to decode,

I agree with other commenters. Quit while you are ahead.... Or buy another kit, build it, and tweak/modify to the max! That way you will always have one that works :) Sandy KB3EOF

Thanks Paul. I realize that they may be blown, but from my recollection they didn't continue shorted. Low power out was the usual symptom IIRC. This is a complete short immediately on power

Good write-up, Joerg! Spot on all! I tuned in Q103/Q104 magic smoke as I was getting close to putting them in and checked with DVM for the dreaded short and found none. Mine is finally in the box and

Jamie, I would trust the scope measurements. You might try pinching the windings on L513 a little closer together to see if the power on 20/30 goes up a little bit.? Then I'd leave it alone. Walt -

You won't be able to tell the difference in what you might squeeze out. I would quit before you short something out.BruceKS4V

Thank you for that. I am computer caveman! I have generally a very hard time eit many of these programs and idiosyncracies of Microsoft Windows. Some hwve gone to later versions of WSJT-X and fldigi,

Most likely culprits are going to be the BS170's, and possibly IC503, from other reports. Paul -- AI7JR

Hello All: It appears my QMX build has gone quite well. I used a couple (actually 3) different measurements of power. I used a Elecraft DL-1 dummy load and first the diode detect method. Then I