Re: Possible QMX/QDX PA Improvement Idea
Yes, probably so. Still, I might play with the idea a bit more. It's all part of the fun.
Tony
AD0VC
________________________________
Sent: Thursday, April 3, 2025 7:35 AM
To: [email protected]
By
mux_folder2001
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#142403
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Re: SWR and PWR does not show lcd
Doesn't show on my pre-assembled unit, either. But since they haven't bothered to put out a QMX+ operating manual, I can't be sure it's supposed to show.
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Braden Glett
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#142402
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Re: RTC battery mistake
Hi Braden
The QMX+ has its own assembly manual. The operating manual is the same for
QMX and QMX+, and any differences between them are identified where they
occur.
73 Hans
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Hans Summers
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#142401
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Re: Possible QMX/QDX PA Improvement Idea
Hi Tony
In my experience, practically there are undesirable effects including loss
of bandwidth (meaning reduced power at higher frequencies), lower power
output and lower efficiency. It's my opinion
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Hans Summers
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#142400
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Re: RTC battery mistake
I didn't even know that the clock settings could be preserved, or that there is a place for a cr2032 battery in my QMX+. I didn't see anything about it in the manual, but of course the Plus doesn't
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Braden Glett
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#142399
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Re: QMX+ Power Output Question
Thanks for your input Dave (and Jeff).? It's good to know my QMX+ is not too far out of line with others.? ?I am not losing any sleep over the lower output on the higher bands, I was mostly
By
secondchancesailor
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#142398
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Re: Possible QMX/QDX PA Improvement Idea
Good idea!
Though I'd think a DC bias at the gates of 0v would mean the 5v swing
is now going from -2.5v to +2.5v, not enough to fully turn on the BS170's.
Perhaps that 2k should go to 2.5v when TX is
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Jerry Gaffke
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#142397
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Re: RTC battery mistake
Thanks for your encouragement Dave. ?I need to learn to remember the highs rather than pondering n the lows! I’m looking forward to trying to get up to speed n this hobby.
Paul
G8MAD
By
Paul G8MAD
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#142396
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Re: RTC battery mistake
Hi Stan
Thanks for your reply. It didn’t occur to me to recheck the battery voltage but it still shows 3.15V on my dvm. I reinserted it ensuring good contacts with the positive pins of the holder.
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Paul G8MAD
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#142395
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Possible QMX/QDX PA Improvement Idea
It occurred to me that the Interface between the ACT08 drivers and the BS170 gates could be AC coupled. A quick simulation with 100nf and a 2k to ground on the gates shows no ill effects. The
By
mux_folder2001
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#142394
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Re: Lin_reg_en
#troubleshooting
Check all the elements connected to the VDD rail and all the places where the VDD rail goes. With some luck you will find a tiny solder whisker or a tiny part cut from an element during construction
By
@Ludwig_DH8WN
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#142393
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Re: QMX+ rev 3 freezes shortly after boot
Not so much in the moment. Maybe I will do a test using a cheap evalboard containing a STM 32. I want to check what will happen in case of VDD = 4.5 V or so. Will it stop? Yes, if not it's no proof
By
@Ludwig_DH8WN
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#142392
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Re: Available Hand Mics for QMX SSB ?
Eric,
I do not see an order page for the mic.
Dean
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Dean, N2TNN
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#142391
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Re: Help with partially fried QMX
Stan - that was super helpful.? Thank you for taking the time to type that out for me/other hams that want to learn by doing (or by destroying).
After i read the earlier post about the pin to T507 i
By
VA2OJD
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#142390
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Re: QMX+ rev 3 freezes shortly after boot
Hi Stan, apologies - you’re right. I mistyped when I said it jumped from 0.8A to 0.2A. The jump was from 0.08A to 0.2A, and it did freeze before I cut power.
I’ll do another sweep of the boards
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Michael Shiplet
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#142389
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Re: QMX and power bank PD
The USB cable is a good option to be able to use any pd power bank and not need to make a custom battery with buck converters and other kit electronics.? Also one less thing in a bag.
Mine runs a
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Jason
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#142388
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Re: QMX and power bank PD
Did a search looking for this kind of assurance. I have a factory built QMX - I've not been able to use it yet - which I was able to power on using those cheap AA battery banks filled with Duracell
By
EI3LH
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#142387
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Re: RTC battery mistake
Paul,
Take heart! Most of the things I teach to younger (and some almost at my age, 80) I learned by mistakes, misunderstandings, and just trying this and trying that. Just the fact that you admitted
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David Wilcox K8WPE
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#142386
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Re: Available Hand Mics for QMX SSB ?
Karl, I cut the cable and soldered each wire to two other 3-wire cables. Each individual wire was insulated with tiny heat shrink tubing, and finally the entire cable at that place was insulated with
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Zrinko Ivan Vukoja
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#142385
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Re: Available Hand Mics for QMX SSB ?
That is very interesting - never thought of using a 50 Ohm speaker. How did you attach the two plugs? My experience with Baofeng mikes is that the wires are very flimsy.
--
Karl Heinz - K5KHK
By
Karl Heinz Kremer - K5KHK
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#142384
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