Re: What are you QRP guys using to measure power?
Bill Cromwell
Hi Arv,
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I assume you have been mining the WIKI associated with nanoVNA-user IO group. I noticed the nanoVNA will do the same work as the "antenna analyzers" and costs a lot less. I noticed it will do a lot of other tricks that those analyzers can't do but it costs a lot less money. It can do things that I can't (or maybe just haven't) but it still costs a lot less money. Did you know about the tiny spectrum analyzer project from some of the same people that is being readied for production? I expect I will be *in* for that too. Look at the radios and other gear that have come available recently from places like um... QRP Labs. It's a good time to be a ham:) 73, Bill KU8H -- bark less - wag more
On 5/31/20 10:32 AM, Arv Evans wrote:
Bill
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Gregg Myers
The lower right 4 pin connections are for a GPS. The 6 pin connector is for upgrading the software.
Will be buying the sockets per recommendation. What page in the manual (assembly or troubleshooting) is this diagram on? Maybe if I look around from there I will be able to figure out what the 6 pin connector next to it is used for. There is also a 4 pin connector on the lower right side. I can read +5v, rxd, and gnd, but cannot decipher the last pin, so it would be nice to figure out where the info on these connectors is in the manual.
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Roger Hill
Rob Just a dumb question, as usual from me: are you sure the dummy load itself is good, no intermittent connections etc? 73 Roger G3YTN ---
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Roger Hill ***************************
On 2020-05-31 10:34, Rob French (KC4UPR) wrote:
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Rob French (KC4UPR)
Bill, I had a dummy load connected abs wad using the built in RF power meter to measure across the dummy load, at the center pin solder joint (on the back of the PCB).
That all makes sense about harmonics. Maybe more salient is that the transistor output seems rock steady whereas the LPF output appears to wander a little (when it's not dropping to 300 mW). Rob KC4UPR
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Re: What are you QRP guys using to measure power?
Arv Evans
Bill Thanks for the encouragement. My main interest in this device is for antenna evaluation and for building and testing crystal filters. At my present level of understanding it appears that it will do very well for both purposes. Seems that over the past few years we are seeing a major change in test equipment for use my hams. It is smaller, has more functions, and is much lower in cost. I like it! 8-) Arv _._
On Sun, May 31, 2020 at 5:19 AM Bill Cromwell <wrcromwell@...> wrote: Hi Arv,
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Bill Cromwell
Hi Rob,
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You may or may not have continuity problems in the low pass filter. Measuring power at the transistor drains is NOT valid. Measurements there will include elevated harmonic energy that is removed by the low pass filter. That is why it is called "low pass filter". When you say you measure output power at the BNC output pin how do you do that? Four or five watts would blow out my RF probe if I tried to do that and if it didn't I would still not be measuring across 50 ohms. There are always things I don't know so I would appreciate if you could explain that to me. It would be more convenient than connecting dummy loads with cables, connectors, adapters, and measuring there. 73, Bill KU8H
On 5/31/20 9:43 AM, Rob French (KC4UPR) wrote:
One more update. Hopefully this will help narrow things down. --
bark less - wag more
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Syd
Will be buying the sockets per recommendation. What page in the manual (assembly or troubleshooting) is this diagram on? Maybe if I look around from there I will be able to figure out what the 6 pin connector next to it is used for. There is also a 4 pin connector on the lower right side. I can read +5v, rxd, and gnd, but cannot decipher the last pin, so it would be nice to figure out where the info on these connectors is in the manual.
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Rob French (KC4UPR)
One more update. Hopefully this will help narrow things down.
This occurs about 10% of the time, where when I go key down, I get ~300 mW output power. An additional thing I noticed... When I measure (using the built-in RF power meter) the level at the drains of the final amp transistors, I always get a solid "5.2" on the display. However, when I measure it at the output BNC center pin, it varies between 3.8-4.5... or else 0.32 or so. So even when I am getting "good" output power, it's still not the same as what I'm seeing at the output of the finals. More to the point, when I measure it at the transistors, the reading is very steady... constant 5.2. When I measure it at the LPF output, it wanders a little. So I suspect this all indicates more and more that it's a problem in the continuity of the LPF, although I'm still surprised that I never see it change while key down (except for the slight wandering during the high power out). What is the chance that this could be a problem with the LPF capacitors, and/or the coupling capacitor (C29 I think)? Should I just go replace these all as a matter of course? Also, for the coils, should I just remove, rewind, and reinstall, possibly with manually removing the enamel? I attempted to use the "burn of the enamel" technique... maybe that just didn't work for me. Regards, Rob KC4UPR
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Re: PTT Tracking
The two cases I’m waiting for from China fell out of 17Track about 2 weeks ago. No idea what that means.
Mike WM4B
From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Dave 'TXJ via groups.io
Hi Folks
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Syd
Haven't found this DC parameter yet. I would like to know what the typical current draw of this unit is in standby and tx mode.
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Re: What are you QRP guys using to measure power?
Bill Cromwell
Hi Arv,
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That USB port is one of the newer ones. My (mis)understanding is that it is called type "C". It is designed so that it can be plugged in either way. Apple had a better idea with the iPhones and iPad. Theirs can be plugged in either way. Of course their design is patented so this new USB connector is NOT interchangeable with the Apple. Maybe some day. I have five or six different formats of those things around here and it is a nuisance keeping them sorted. I had to pay more for my nanoVNA but it is in a case and included a printed chart of the menu system. It also had some buyer assurance that it was not just junk (Amazon). There are a lot of new tricks to learn but I have already made some serious antenna improvements and uncovered a couple of poor PL-259 connections as well. More improvements on the way. And then on to check out some filters. 73, Bill KU8H bark less - wag more
On 5/30/20 7:11 PM, Arv Evans wrote:
I just received a new NanoVNA. It was on sale for $24.95 USD.
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Re: QCX - Problem with new 30 meter QCX Initial Alignment
George Korper
Good news. Great persistence. Ron 's ugly jumper does it again....... Don, since Ron showed me the way I saved a couple of rigs. And a couple of towels. You can learn a whole helluva lot from this Group.
On Sun, May 31, 2020 at 5:44 AM Don W4ZYT <w4zyt.don@...> wrote: Decided to give it another shot and went through all the joints once again, ran a fresh jumper from the Rotor B tab to pin 13 of IC-2 and Voila! It worked!
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Re: QCX - Problem with new 30 meter QCX Initial Alignment
Don W4ZYT
Decided to give it another shot and went through all the joints once again, ran a fresh jumper from the Rotor B tab to pin 13 of IC-2 and Voila! It worked!
I was able to proceed through the alignment procedure which seemed to go well, and am moving on to the next steps - learning the operation of the transceiver and checking output, receiver, etc. and putting it on the air. Many thanks to Ron and Hans and others who pointed me in the right direction. I have learned a lot so far building this amazing radio. Vy 73, Don W4ZYT
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Re: What are you QRP guys using to measure power?
Hi folks,
I have an HP431C, Marconi 2955a and a homebrew AD8307 meter from a QST design. All read near enough exactly the same for anyone but someone with OCD. The most user friendly is the AD8307 meter with its accompanying 40dB tap, it was easy to build too. 73 Dave.
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PTT Tracking
Hi Folks
Anyone else having issues with tracking their goodies coming from Hans at the moment? Using 17 Track I'm just getting a number not registered message, this is for two packages, one I received a week ago has full tracking right up to delivery. 73 Dave.
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Re: [help] Only noise being seen while IQ balance / phase lo / phase hi.
Alan G4ZFQ
Have you checked voltages each side of R37? Is C22 installed the correct way round? Is it leaky?Jose, Before you do any pictures please check this. Or, at least confirm you have checked. Voltages here will tell if IC10 is faulty. Reiner has said the same. 73 Alan G4ZFQ
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Re: What are you QRP guys using to measure power?
Looks sweet. Is this your design, Jack? Is the design freely available?
Julian N4JO
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Re: QCX+ info ?
Hans Summers
Hi Mike QCX+ is available for pre-order now, as are all the accessories and options. The following are currently being prepared and anticipated shipment is mid-June:
The manual is also being prepared and will be published before shipment starts. Note that the circuit and firmware are the same as QCX. There are many changes in the manual, they are all changes about the assembly. The operational and theoretical sections are unchanged. 73 Hans G0UPL http://qrp-labs.com
On Sat, May 30, 2020 at 11:08 PM Mike <mike@...> wrote: Do we have a date for release of the QCX+ or the build documentation?
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Re: [help] Only noise being seen while IQ balance / phase lo / phase hi.
Jose Tent
On Sat, May 30, 2020 at 07:13 AM, <ed.j.tink@...> wrote:
Happy to do it. and thanks for the offer. I'll post some thing tomorrow. I'm too blurry eyed after working few hours today. Posting my soldering acumen for everyone to see feels a bit like posting my picture in the buff.... But I'll do it.
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Mike Easterbrook
Hi Rob No - have not done any more on key shaping. I was hoping for more feedback from the group as don't fully understand the circuit. I would have thought (wrongly?) that malfunction in Q4/6 would result in no keying at all. Allison did make a comment on L4. Small adjustment either way reduces RF out so did not look further. I'll take another look at this with respect to key envelope & revert. 50 years since I used CW & very slow progress getting up to speed so a few key clicks aren't going to upset too many folks yet. Got me wondering if this is an uncommon problem or just reflects few users with the means (or motivation) to look at it. 73 Mike 9M2LXM
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