Re: QCX no transmit after assembly
Hi, Andre
I would expect Q5 source to be just about 0 (zero) ohms to
ground, and the drain should be just about infinite. 140 ohms
would send whatever is coming out of the transmitter into the
receiver. Not a good thing. So Q5 appears to be bad. The purpose
of Q5 is? to connect the receiver to the antenna when receiving,
and to disconnect the receiver front end on transmit.
Install the transistors, leave R42 dangling, connect a voltmeter
to one of the output transistor drains, connect a dummy load, and
apply power. If the drain voltage remains at 0, reconnect R42 and
try again. Still no volts? You've got a radio. 12 volts? You're
still transmitting and receiving at the same time. The dummy load
is to keep the voltage on the drains from spiking and blowing the
new transistors.
73
Jim
On 09/26/2018 03:50 PM, atfu wrote:
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Hi Jim,
tnx, once again. I removed Q6, and also Q1-3. Voltage at Q4 gate
is 0, as it should.
Next I checked resistance from G4 drain to GND (R42 disconnected):
140 ohms. So I replaced Q4.
(I also checked Q5 to GND: 140 ohms. Is that OK?)
So the microcontroller looks ok. Can I now put back Q6, Q1-3, and
R42 without first calling the fire brigade?
As Alan said, pity that we don't sleep at the same time.
73 de andre
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Re: Ultimate 3S SI5351error
I had the same problem on my first u3s, I resoldered a pin on the main chip socket, IIRC, pin 11. This solved mine, check the joints it may help.?
?Andy
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True, but only for 2 minutes. By setting to park it means that the receiver can be on for a long time, until the next tx frame which may enable more spots to be heard, I tx 3 times an hour and receive for the rest bar calibration.?
More than one way to skin a cat depending on which operating instructions are read.
Andy
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Re: Ultimate 3S SI5351error
AC Coupling
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On 27/09/2018 19:13, tl10200 via Groups.Io wrote: Ok Hans, here's a screenshot of clock 2 on the synth module. I guess I should have said 'ringy' rather than 'lumpy' :). At first I could not get it to repeat the problem. The U3S and the SI5351 synth module sat overnight, connected to each other. When first I energized the U3S I got just the "Error: SI5351" without the "No Clk", just like it comes up without the SI5351 synth module attached. There was no output from any of the three clocks. I removed the SI5351 synth module from it's socket, waited a half hour, plugged it back in, turned it on, and this time I got "Error: SI5351a No Clk". This time the 9 MHz signal was present on clock 2 (nothing on the other two). This is the condition where I took the screenshot.
Of course, the U3S module is still non-functional, with or without the synth module connected. Just stops at the error message and doesn't respond to buttons.
Hope this helps,
Tom N7JX
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But there is a specific RX mode, you don¡¯t have to use PARK mode to receive, i.e;
This mode is new in firmware version v3.11. It is specifically designed for when you wish to use the Ultimate 3S kit with the QRP Labs Receiver kit. It is a mode configuration like all the others in the kit. This mode is designed with standard WSPR reception in mind. Accordingly the ¡°RX¡± mode starts on an even minute, and is active for 2 minutes. The mode sets the Ultimate 3S ¡°Clk1¡± output to 4x the displayed frequency, suitable for driving the quadrature Local Oscillator (LO) in the QRP Labs Receiver kit.
73 Ken G4apb?
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Re: Still digging... looking for a low audio issue
#problem
#qcx
Well thanks to the help form Ron Taylor - wa7gil who pointed out a possible issue that he encountered in diagnosing a similar issue with his QCX.? He had asked me to look at R21? 7.5k & R35 750k resistors.? Ron asked me to look to see if those 2 resistors were switched.? Well guess what?? Those are indeed are switched.? I was able to verify this however didn't have the time to switch them.? I do believe we have found the smoking gun.? Ron had the same issue and experienced the same problem as I.? I will report back after I've correct my assembly error with my final results.
73;
Kurt - W2MW
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Freudian slip? Hi.? Recently I have been using? Blu Tack to hold down my Morse Paddle and was amazed at? the gripping power.?
Thanks for the useful tip.
Richard G0ILN.
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Re: CLOCK Kit problem - incorrect LOC calculation
#clock
#qlg
Hello Lexa
Apologies it has taken me time to get to this, very busy here...?
So your displayed Maidenhead grid subsquare is?JN79EW but in reality you know it should be?JN79EX.
Reaching back into the far away mists of time, I recalled that we had a similar problem in the Ultimate3/3S kit a long while ago. I investigated the firmware version history for the U3/U3S at? and I saw that sure enough, the issue was fixed in version v3.09 released on 21-Oct-2015, with the following comment: Bug fix: Incorrect 6th Maidenhead character in 10% of QTHs
The Clock firmware was initially derived from some of the modules of the Ultimate3/3S of course. So presumably also had the issue with the Maidenhead calculation of the 6th character. I looked at the Clock firmware version history here? and see that the current version c1.01 was released on 31-Aug-2015 (the subsequent label c1.01a on 01-Dec-2015 was just a recompilation under AVR Studio version 10). Therefore the current clock firmware predates the Ultimate3S bug fix to the same issue.?
Therefore it appeared highly likely to me that the Clock firmware has the rounding error that caused the bug earlier in the U3 code. To check that I dug back through the code archives and found the two lines of code difference between version 3.08 and 3.09 of the Ultimate3S; and I verified that the current Clock firmware still has the same code as U3S v3.08. So this IS the explanation. And will be easy to fix.?
Lexa do you have an AVR Progammer, so I can just email the .hex file? Or do I need to snailmail you an actual chip?
73 Hans G0UPL
On Sat, Sep 22, 2018 at 1:59 PM Lexa, OK1DST < kobranov@...> wrote: Hi Hans,
is there any chance for some evaluation of Loc calculation method/precision in the Clock module??
Thanks
Lexa, OK1DST
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Re: Ultimate 3S SI5351error
Hello?
Please can you take a screenshot or picture of the screen, to show what you mean by "?MHz 'lumpy' square wave 5.5V p-p."
73 Hans G0UPL
On Wed, Sep 26, 2018 at 10:25 PM tl10200 via Groups.Io <tl10200= [email protected]> wrote: I recently bought the? Ultimate 3S deluxe 6-band set. So far I've built the U3S and the SI5351 synth module.? When I powered on the U3S (with the SI5351a attached), I got the "Diagonostic" screen. When I pressed the left button I got the bootup screen, then "Error: SI5351a No Clk".? With the SI5351 synth module attached, I checked the clock outputs on the synth module. Clock 0 and 1: no output. Clock 2: 9 MHz 'lumpy' square wave 5.5V p-p.
If I remove the synth module, and just power on the U3S by itself, it boots, and stops with "Error: SI5351" without the "No Clk". Thats it. It doesn't respond to button presses; it just hangs.
I read the troubleshooting page and found a similar error, but only on the older Ultimate 3. This is the new Ultimate 3S, firmware version 3.12A.
I am using a Siglent SPD3303xe power supply so there are no issues with dirty DC power.
Any help most appreciated.
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Re: QCX no transmit after assembly
Hi Alan,
I understand Jim as saying: IF Q4@gate > 0, THEN suspect IC2; ELSE suspect IC3. So we are now in the ELSE-clause, as you also suggested. I have the sidecutter on the bench so as to remove IC3 while waiting for the replacement chip to arrive. This time I'll use a precision socket as a go-between -- unless someone dissuades me otherwise.
@Clint: Thanks for this vy good thought! I was tempted to use a Dremel, at least on the middle pins. Now I'll definitely try to do it just with the sidecutter.
73 de andre
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Re: QCX no transmit after assembly
Remove it in the way Jim suggested. Some recommend a Dremel-type tool to
cut each pin before removal. A small, sharp sidecutter may be an
alternative.
73 Alan G4ZFQ
Side cutters work nicely, even the cheap ?3 pairs are good enough if not worn out.?
A Dremel will spray fine metal dust around which needs to be cleaned up but can you be sure you got it all?
-- Clint. M0UAW IO83
No trees were harmed in the sending of this mail. However, a large number of electrons were greatly inconvenienced.
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Re: QCX no transmit after assembly
so you are suggesting that I should replace IC3, put in the new Qs and reconnect R42, right? Andre, It is a pity Jim has not commented about this. But you have said that in RX mode IC3 pin 3 is high, 5V. This is wrong. You say all other voltages on IC3 are correct. (Pin 9 is 0.32V, near zero, may be normal.) That shows the IC is faulty. I am unsure of the sequence of events. Jim has shown Q4 was faulty. (Not the micro as he had experienced.) But it seems to me that merely switching Q6 on would have no effect if the BS170 gates were at zero volts. But in the fault situation you noticed current variations. When testing you saw 5.83V on IC3 pin 3. I think this must have come from the 12V on the drain of a BS170 that had shorted drain to gate. It would be good if someone else commented. Anything that I could try before embarking on this major piece of surgery? (I don't mind the time spent but I am afraid of ripping off pads or traces.)
Remove it in the way Jim suggested. Some recommend a Dremel-type tool to cut each pin before removal. A small, sharp sidecutter may be an alternative. 73 Alan G4ZFQ
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Quite frankly I thought I was seeing things!! Yes I have fallen into that trap of not using my glasses several times. Surely your apology was accepted!! LOL
On Wed, Sep 26, 2018 at 2:41 PM Andy G0FTD via Groups.Io <punkbiscuit= [email protected]> wrote: On Wed, Sep 26, 2018 at 02:53 PM, Chris Wilson wrote:
I think you perhaps need to review that link ;) <LOL>
Best laugh I've had all day ;-)
73 de Andy
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Re: QCX no transmit after assembly
Hi Alan,
so you are suggesting that I should replace IC3, put in the new Qs and reconnect R42, right? Funny, when I soldered the IC3 directly on the board, it didn't feel right: I thought that there really ought to be a socket in between -- just in case ;-)
Anything that I could try before embarking on this major piece of surgery? (I don't mind the time spent but I am afraid of ripping off pads or traces.)
@Jim was suggesting that the microcontroller (IC2) is off. That would be much easier to replace, as it is mounted on a socket.
73 de andre
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Re: QCX no transmit after assembly
Measurements at IC3 in RX: All pins ok, except
pin 3 = 4.89 V (should be 0), pin 9 = 0,32 (should be 0). Andre That makes IC3 faulty. Looks like Jim and I are both right. It's the first time I remember Q4 causing the PA breakdown. 73 Alan G4ZFQ
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Re: QCX no transmit after assembly
Forgot to say: After replacing Q4 resistance from drain to GND is infinite.
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Re: QCX no transmit after assembly
Hi Jim,
tnx, once again. I removed Q6, and also Q1-3. Voltage at Q4 gate is 0, as it should.
Next I checked resistance from G4 drain to GND (R42 disconnected): 140 ohms. So I replaced Q4.
(I also checked Q5 to GND: 140 ohms. Is that OK?)
So the microcontroller looks ok. Can I now put back Q6, Q1-3, and R42 without first calling the fire brigade?
As Alan said, pity that we don't sleep at the same time.
73 de andre
|
I recently bought the? Ultimate 3S deluxe 6-band set. So far I've built the U3S and the SI5351 synth module.? When I powered on the U3S (with the SI5351a attached), I got the "Diagonostic" screen. When I pressed the left button I got the bootup screen, then "Error: SI5351a No Clk".? With the SI5351 synth module attached, I checked the clock outputs on the synth module. Clock 0 and 1: no output. Clock 2: 9 MHz 'lumpy' square wave 5.5V p-p.
If I remove the synth module, and just power on the U3S by itself, it boots, and stops with "Error: SI5351" without the "No Clk". Thats it. It doesn't respond to button presses; it just hangs.
I read the troubleshooting page and found a similar error, but only on the older Ultimate 3. This is the new Ultimate 3S, firmware version 3.12A.
I am using a Siglent SPD3303xe power supply so there are no issues with dirty DC power.
Any help most appreciated.
|
On Wed, Sep 26, 2018 at 02:53 PM, Chris Wilson wrote:
I think you perhaps need to review that link ;) <LOL>
Best laugh I've had all day ;-) 73 de Andy
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Oh boy, I hope I don't get banned. Yes, my face is red! That's what I get for typing without glasses, Sorry Cecil !!!
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James Daldry W4JED
M0RON
Kurt Zimmerman