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QMX unboxing and a couple of surprises

 

Hans,
I received my QMX (order number 72448) yesterday but didn¡¯t have time to unbox it until today.

I opened the packaging over a tray on the floor in order to minimise the chances of losing anything.

The first thing I did was to check off all components against the parts list. There were two knobs in a separate bag and another two in the main packaging, so I¡¯m two knobs up! The knobs all appear to be the same size.

I then removed the PCBs from their anti static bag and immediately photographed them. The LCD board was broken off from the main board - I¡¯m not sure if that¡¯s to fit them in the bag or whether it got damaged in transit.

Looking at the photos I saw that C205 and C210 had broken off the main board. Coincidentally one of them appeared in one of the other photos, and I found them both on the tray.


C210 is a 100nF decoupling capacitor and might not be critical, but C205 (47nF) is on the processor reset line and might be essential.

I¡¯m quite happy to resolder the capacitors but neither of them check out with their correct value (my DVM has a capacitance range, I checked some through hole capacitors to confirm that it was working).

My suspicion is that the capacitors got knocked off by the LCD board in transit, which is why they were in the packaging.

Hans, if the boards are supposed to be separated, can I suggest something like a piece of card slipped between the two to prevent the capacitors from being knocked off?

If I order some replacement capacitors, I¡¯m thinking of substituting 47nF for C210 so I¡¯ve only got to order a couple of the same value.

Any comments/suggestions gratefully received.

73
John
G4YTJ
 

John, my boards arrived as one and my first job was to separate them and smooth all the edges. Today I will check for missing parts or poor soldering. If time permits might start assembling.

---------------------------------
73 de Marek SP9TKW
 

Hello John

The first thing I did was to check off all components against the parts list. There were two knobs in a separate bag and another two in the main packaging, so I¡¯m two knobs up! The knobs all appear to be the same size.

Bonus for you! Kick for my colleagues...??

I then removed the PCBs from their anti static bag and immediately photographed them. The LCD board was broken off from the main board - I¡¯m not sure if that¡¯s to fit them in the bag or whether it got damaged in transit.

That's not how we pack them, we pack them in one piece. Not broken apart. So this must be a transit thing. Nevertheless it's the first time I have heard of this so I think it's not common, and in any case the first thing you are going to do is break the boards apart so it should not matter.??


Looking at the photos I saw that C205 and C210 had broken off the main board. Coincidentally one of them appeared in one of the other photos, and I found them both on the tray.
C210 is a 100nF decoupling capacitor and might not be critical, but C205 (47nF) is on the processor reset line and might be essential.

Neither of these capacitors are critical. I believe the 47nF on the reset line is only required during Flash programming of the bootloader. Once done, it is not a requirement. The other decoupling capacitor as you say, is a prudence (follow all datasheet recommendations on capacitors everywhere) but it should still work without it.??

I¡¯m quite happy to resolder the capacitors but neither of them check out with their correct value (my DVM has a capacitance range, I checked some through hole capacitors to confirm that it was working).

I wouldn't worry about that either. I don't use expensive precision capacitors for the capacitor positions where it is not critical. The expensive capacitors go in the LPFs and BPFs.??

My suspicion is that the capacitors got knocked off by the LCD board in transit, which is why they were in the packaging.

I suspect you are right?

Hans, if the boards are supposed to be separated, can I suggest something like a piece of card slipped between the two to prevent the capacitors from being knocked off?

The PCBs aren't supposed to be in two parts...?

If I order some replacement capacitors, I¡¯m thinking of substituting 47nF for C210 so I¡¯ve only got to order a couple of the same value.

I would just use the supplied ones. Or not bother...??

Any comments/suggestions gratefully received.

?I'm sorry to hear about the mishaps but I think these are non-critical things, that won't affect anything about the build outcome - so I'd just proceed regardless...

73 Hans G0UPL
 

Hans,

Thanks for your prompt reply. I¡¯d already ordered some 47nF capacitors so I¡¯ll probably fit them, but it¡¯s nice to know that they aren¡¯t critical.

73

John
G4YTJ
 

2nd QMX arrived Monday. My PCBs were split too. Package did not look as if it was damaged. Have not checked out the rest of the contents.?
--
73, Dan? NM3A
 

Mine arrived today - box was damaged a bit by customs/courier. All content in tact. Boards solid in one piece and no missing/broken elements (at least didn't found them at initial inspection).

BTW it was record delivery time :

- Collection 4 days (including Sunday)

- Grezimir to Dublin 19h (yes 19hours !!!- still cant believe as last time was about a week)

- Customs/local TNT depot? 1.5 day

Thank you Hans - looks they finally taking it seriously (at least outside of Ireland :D )

73 de Robert EI9ILB

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