Re: Unable to receive anything on my 20m
#chat
Ok, so here you have the video example of the alignment process I performed. (Not too precise for having to hold the camer with the other hand, but you get the idea of the amplitude jump around and the values I get):
Thanks for the time you take to help me, I really appreciate it.
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Re: Unable to receive anything on my 20m
#chat
And yes, I tune my loop antenna and I am able to hear the increase in the background noise.
Thanks again, I am really lost with this because everything seems to be fine (at least in the receiving part). I will upload the video of the tuning process so that you can see how the amplitude bars jump around (which I assume it can be a problem for the receiving part)
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Re: Unable to receive anything on my 20m
#chat
Yes, I get the loud tone in the headphones and I've also checked the continuity across L1, L2, L3. However I did it only with the audible signal of continuity. Should I specifically check the resistance?
Thanks for your response.
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Happy camper! I ordered 2 new inductors should be tomorrow.?
RX seems sensitive enough, can almost hear what the 7610 hears!
I ordered 2 new micros, seemed easier than doing it myself.
The audio does seem a bit on low side OK but could be louder for my 72 yr old ears.
Thanks everyone for suggestions that made this a quick fix.
BTW I was one of the first to sign up for kits at Friedrichstaufen in 2017, it was a treat to talk with chaps there about this great radio.
This will make a great portable rig and be used for demos at JOTA this year.
Tim W4YN
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Re: Unable to receive anything on my 20m
#chat
Good point - my post was poorly worded - they have a very narrow in-tune range for a given frequency.
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Re: Unable to receive anything on my 20m
#chat
I think it's misleading to say they have a small tuning range. The range is fairly large, but the bandwidth without retuning is small. Indeed, many mag loops are multiband, but with less performance on some bands than others.
Jack, W8TEE
On Monday, September 17, 2018, 6:26:27 PM EDT, Rich <rich@...> wrote:
And - just in case you aren't aware, loop antennas have an extremely small tuning range.? You need to turn the antenna tuning knob slowly until you hear an increase in background noise.
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Re: Unable to receive anything on my 20m
#chat
And - just in case you aren't aware, loop antennas have an extremely small tuning range.? You need to turn the antenna tuning knob slowly until you hear an increase in background noise.
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Re: Unable to receive anything on my 20m
#chat
Did you get the loud tone in the headphones when aligning?? Have you checked that you have continuity (with an ohm meter) across L1, L2, and L3?
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Re: QCX died after one QSO
Well the blocks are back after an evening of running WSPR ok.
Switched it on tonight and blocks along the top again.
Reseated the micro-controller, no luck, re soldered the socket pins and still no luck.
I'll start checking voltages when I have more time.
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Hi all
The early L5/L6 did have some coating on the leads that made them difficult to solder, and also they were quite fragile. From a quite early batch we changed supplier to a better inductor, and I don't think these problems occur now.?
For replacement: the value is very non-critical, you don't need to be fussy about finding an exact replacement.?
73 Hans G0UPL
On Mon, Sep 17, 2018 at 8:01 PM Frank Waarsenburg < Frank@...> wrote: Same here. L5 was replaced by another choke and that solved my startup problem. Serial 887. Looks like early L5s were causing problems sometimes.
72 Frank PA3CNO
Verstuurd vanaf mijn iPad
> Op 17 sep. 2018 om 18:08 heeft neil@... het volgende geschreven:
>
> Hi Tim,
>
> Interesting, I also took a long time to get round to my early kit (1.00b FW) and just had exactly the same problem.
> I tried shorting out the L5 (post pwrup modification) as suggested above and mine also sprang into life.
> Seems the modification is not always a complete solution.
>
> 73,
> Neil? G4BRK
>
>
>
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Unable to receive anything on my 20m
#chat
A new chat has been created:
Hi all,?
Months after I purchased the kit, I found some spare time to build it. I think everything went fine during the alignment process. I am able to find a maximum in the peak BPF menu and the plates of the trimmer capacitor are somewhere in their range.
However, I was unable to hear any station after several days and I am starting to think that there might be a problem.
Regarding this issue I wanted to ask whether it is possible to receive anything using this portable loop antenna:?
Do you think that could be the "problem"?? Or should I look for a hardware failure?
I do not know what can be wrong, the only thing I can think of is that during the alignment process, in the I-Q balance, Phase LO and Phase Hi menus, the amplitude bars jump around maybe too much (However, I can find a minimum value even though it does not remain "static")
I'll record a video of this so that you can actually see it if you think it is helpful.
This is my first transceiver ever, so I am a newbie in this topic and I feel a little bit overwhelmed about all the things that could be wrong. Maybe you can help me a little bit with your expertise on how should I proceed.
Regards,
Gabriel
View/Join This Chat
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Same here. L5 was replaced by another choke and that solved my startup problem. Serial 887. Looks like early L5s were causing problems sometimes.
72 Frank PA3CNO
Verstuurd vanaf mijn iPad
toggle quoted message
Show quoted text
Op 17 sep. 2018 om 18:08 heeft neil@... het volgende geschreven:
Hi Tim,
Interesting, I also took a long time to get round to my early kit (1.00b FW) and just had exactly the same problem.
I tried shorting out the L5 (post pwrup modification) as suggested above and mine also sprang into life.
Seems the modification is not always a complete solution.
73,
Neil G4BRK
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The early L5's came with the leads coated with a substance that
interfered with soldering, forming a higher impedance joint of several
hundred ohms (DVM measurable by removing the ATMega).
The modification itself is sound.
toggle quoted message
Show quoted text
On 17/09/2018 17:08, neil@... wrote: Hi Tim,
Interesting, I also took a long time to get round to my early kit (1.00b FW) and just had exactly the same problem.
I tried shorting out the L5 (post pwrup modification) as suggested above and mine also sprang into life.
Seems the modification is not always a complete solution.
73,
Neil G4BRK
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I would remove the shorting link and replace L5 (which I found to be
very fragile) with something from the junk box directly between Pins 7
and 20. As it's purpose is to keep digital noise out of the analogue
circuitry, anything from 47uH to 270uH will do, it is not a critical
value component.
This 'Unreliable microcontroller start-up at power-on' modification is
documented on the website, refer to that and take whatever action you
feel appropriate.
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Hi Tim,
Interesting, I also took a long time to get round to my early kit (1.00b FW) and just had exactly the same problem.
I tried shorting out the L5 (post pwrup modification) as suggested above and mine also sprang into life.
Seems the modification is not always a complete solution.
73,
Neil G4BRK
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Re: Progrock, gps and receiver, gps pick up.
Hi Alan,?
Touching the pins with a finger on the shaft of a screwdriver injects an ac hum. I had traced back to c9-11 and all good so it had to be a problem in the front end.?
Voltage on pins 7 and 9 of fst3253 were 2.5v, voltages on c3-6 were good. Good voltages on pins 10-13. Q1 and 2 both looked suspect with little voltage on some pins, Changed them and voltages came up quite a bit.?
My last kit from QRP Labs had a dud transistor and also 4 out of 5 7809's bought recently had 6.07v out, only one was 9v.
In future I think I'll check components as I fit them, no matter where they are from, ?may take longer to build but it may avoid hours of trouble shooting.?
Thanks,?
Andy
Andy.
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Shorting out L5 that was placed between Pins 7 and 20 did the trick?
Now both Micros start up
Do i put L5 back to original location ?
On to doing calibrations etc
Tim?
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One pin was 4.88 V the other 4,38 V, current draw 100 ma.
Tim
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Was this mod performed?
73; Kurt - W2MW
-------- Original Message --------
Subject: Re: [QRPLabs] Dead on start up
From: "g4sra via " <g4sra@...>
Date: Mon, September 17, 2018 9:15 am
To: [email protected]
On 17/09/2018 13:24, Tim O'Rourke wrote:
> Swapped micro from the other kit. What are chances both could have gotten thru un-programmed?
I would have thought you would have to be very unlucky.
> Acts the same with either processor. Have a bit less than 5 volts on pins 7 and 20.
> Is it possible to do a complete programming with AVR USB programmer?
Yes. Do NOT erase the EEPROM section of the ATMega.
If the programming is not at fault you gain nothing.
I suggested the swap because it is a quick and easy test.
As it still does not work, I would now invest more time thoroughly
checking other options.
Re Pins 7 & 20.
How much 'a bit less than 5 volts' ?
Enough to imply excessive current draw ? assuming not.....
Note, it is the relationship between the rise time at switch on of these
two pins that is critical. As a quick and dirty test strap them together
with a shorting link and then power up the QCX to see if it makes any
difference.
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jjpurdum
Andy Kerrison
M0RON
Kurt Zimmerman