Re: Faulty Progrock2 - no response to ticket
#progrock2
Hi Steve,
I suppose I could do that. I did update the ticket with more info at one point and have tried emails but not a single response to any of those.
Peter
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Given the observations you made, using a common-mode choke on the antenna feedline could be a solution. A common-mode choke can help suppress common-mode noise by preventing it from entering the antenna system. It works by presenting a high impedance to common-mode signals, which seems to be more sensitive when the QCX is on, while allowing differential-mode signals (the desired signals) to pass through.
-- QDX and QMX Owner/Operator.
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Re: RF preamp for power amp - HF and 6 mtrs. Magic silicon does all.
>>>The main question Allison is do you agree with the splitting of the second feedback resistor as I did to do the maths.? ?
It is not my analysis beyond eyeball.? Not a debate for me.
>>Indeed for the? AD 8009 the datasheet? recommends? about a? 50R resistor in the output drive line to? reduce chance of instability in the amplifier.?
>THe datasheet is a bit coy on the conditions that lead to such instability.? Yes I refer to the? 8009.? ?IN the case in question? the OP resistors have been put in? parallel to? ensure that can dissipate? up to? >0.5? W? that is what makes me suspect that those reisistors are there not only for stability reasons but also as? a form of power dump if the? RHS transformer is left unterminated.?
Unterminated transformer has a reflected condition that with dependencies will be reactive and op amps dislike reactive loads.?
Adding resistance makes it less so.? IF your driving a mosfet reactive in the normal case.
?
>Are there any? dual? Video amps of this type (two to a package )? that you know of? which? can do a similar duty at HF? to? 50 Mhz drive? I get the impression that this OPA is? pretty much unique in this >regard.?
NOt studied and likely the LT1254 series (dual 1253) that are fairly old likely qualify.? That was the driver use by
Elecraft in the K2.
>I will include a? photo of a commercial application that uses this type of? Tx chip but I have some considerable reservations about what is shown.? Specifically there appear to be be cappies in the lines >from the? driver transformer to the OPA . This would mean that? ?there is no way that the signal bias can get to the op amp.. Clearly there could be components under the PCb but given there is a heat >sink there , that seems unlikely.? The alternate is that the UKR Mafr has published a false photo and what is supplied does work and is subtly? different from the photo. This design has zero filtering post >the? RF power amp mosfets.? ?I include it mainly because it shows how the transformers? were implemented as hand wound designs and not? commericial designs as per schematic supplied (or a completely different application).
As to filtering the board is too small and a wideband design so that would be on the input and output sides as needed. The picture does not obviously agree with what you say.? The backside of the board and whats under the part is not shown. heatsink is not a limitation.? ?Is it more than a two layer board?? ?I find when I do my own work I get better answers.? I always find a copy of a bad copy is generally bad.? ?Best case for that is many of the Motorola apnotes are not a predictable nor reliable when copies are made and subtle changes added. As a note generally those are at best guides or advertising.? I prefer to look at all with a critical eye. Generally I do not use those opamps due to other factors like generally high power consumption and higher noise figures. -- Allison ------------------ Post online only,? direct email will go to a bit bucket.
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Re: looking for non-US keyer chip
These kits are, of course, legal, as the K3NG code is free and open source. But it's equally true that the sellers of these kits are required to make any changes that they make to the code publicly available, as it is licensed under GPLv3. Some of the Asian kit sellers do not honor that requirement, and I would recommend avoiding those. Only buy kits that work on a standard build of K3NG, or disclose the changes that need to be made.
Actual purpose-built keyer chips like the old Curtis keyers are a thing of the past. All of the current day keyer chips I know about, such as the ones from K1EL, are simply pre-programmed microcontrollers. I suppose it would also be possible to create a purpose-built keyer by pre-programming a CPLD or FPGA, but nobody that I know of has done that. Reproducing a Curtis keyer on a programmable logic device might be an interesting project! (So far as I know those contained no microcode; they were entirely logic-level implementations.)
On Tue, Mar 5, 2024 at 1:19?PM Rick Williams - VE7TK via <ve7tk= [email protected]> wrote: A slight diversion if I may. I've been following this thread and have come across several K3NG clones that seem "less expensive" than I can source the parts?
There are also several clones out there that are available for less than I can get the parts. Of course the manuals leave a bit to be desired.
?
Basic:
?
Full Featured w/Display
?
The Nano Keyer is unclear on the version (if any) of the source code and the Funtronics indicates that "you have to modify the pin definitions part in the sketch as we have different pin definitions from the original K3NG arduino code."
?
I'd be curious if anyone has tried either of these packages?
?
Thanks,
--
73, Rick
VE7TK
Website:
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Re: Another QMX Receive Issue Thread
Martin, Check L503 to see If it has been damaged ( open circuit).
JZ KJ4A?
On Tue, Mar 5, 2024, 1:17?AM Martin < martin@...> wrote: I had the same problem and refitted the IC and installed the diode.
Despite the diode, the QM went deaf again after some FT8 transmissions. ??
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Re: looking for non-US keyer chip
A slight diversion if I may. I've been following this thread and have come across several K3NG clones that seem "less expensive" than I can source the parts?
There are also several clones out there that are available for less than I can get the parts. Of course the manuals leave a bit to be desired.
?
Basic:
?
Full Featured w/Display
?
The Nano Keyer is unclear on the version (if any) of the source code and the Funtronics indicates that "you have to modify the pin definitions part in the sketch as we have different pin definitions from the original K3NG arduino code."
?
I'd be curious if anyone has tried either of these packages?
?
Thanks,
-- 73, Rick VE7TK Website:
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Re: QMX and iPhone for digital modes
Unfortunately iFTx still needs work doing it to make it functional out in the field, whilst it is possible to fudge your way through making data contacts, the data exchange regularly fails and when it succeeds it will give spurious(wrong) signal strength reports, on the logging side of things it will log yourself as a contact as well as the station you are having a QSO with, so it looks like you have a normal qso (with wrong signal reports) and also one contact with you as the sender and receiver. Despite an initial response from the app creator saying what updates etc will be implemented, I have asked three times since when we will get an update to the app and nothing, no reply, so take from that what you will, if anyone reading this is having regular success with the signal reports and logging I would love to hear from them so I can get it working reliably.
I have used the iFTx app along with a lightning connector to usb adapter to successfully operate FT4/8 with the iPhone and QMX.? The first adapter I purchased did not switch the audio path to the lightning connector.? I purchased a second one that included the audio path in the product description and it has worked well.? The VOX must be enabled in the digital interface menu on the QMX.? Here is a link to the adapter that has worked for me.
Roger KF9D
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Re: QMX and iPhone for digital modes
Roger KF9D via groups.io kirjoitti
5.3.2024 klo 16.31:
I have used the iFTx app along with a lightning connector to usb
adapter to successfully operate FT4/8 with the iPhone and QMX.?
The first adapter I purchased did not switch the audio path to the
lightning connector.? I purchased a second one that included the
audio path in the product description and it has worked well.? The
VOX must be enabled in the digital interface menu on the QMX.?
Here is a link to the adapter that has worked for me.
Roger KF9D
_._,_._,_
I downloaded the application - RX works fine, but TX does not
send!? I have set VOX ON in the settings.
Any suggestions on what to check, iPhone 12MAX+
?
Erkki OH6NMY
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Re: RF preamp for power amp - HF and 6 mtrs. Magic silicon does all.
Why do you say there is no input bias?? There appears to be a divider from +V on pin 8, via the 1kR under the chip to the second 1kR and bypass cap to the left of the chip.? Pins 3 and 5 look like they are tied at that junction under the chip.
/Don W3MW
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Here's the page I used to convert one. Think O paid about $25 US for it.
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This email originated from outside of Samford University. Please consider carefully whether you should click on any links, open any attachments,
or provide any information.
I have been using a repurposed server power supply for my shack.? ?They are very cheap on Ebay. I bought three of them. think I paid $20 each.? They provide up to 55 amps of power.? ?They're designed to be quiet and run 24/7/365.? They put out 12v but depending
on the model can be modified to put out 13.8v.? I modified mine for 13.8v. Works great.?
For my QRP setup in just fine with a battery.?
73
Eric?
-- John KY4WW
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I advise against the little buck/boost converters currently available from Amazon and other places.? I wasted many days chasing intermittent problems on a U3S that all instantly went away when I swapped it out for an LM7805.? A large electrolytic on the switcher didn't seem to help either.??
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Just wanted to share what I ended up doing for my latest QDX build. This is the first of 3 I intend eventually to operate remotely and probably into a Hardrock 50, so reliability is key. I'm loving the QDX only connecting to the computer with a single USB, no audio controls/cables, and directly operating in WJST-X. A few less things to go wrong, especially operating remote.?
Stats:
Post Mar 2023 Rev 5 (T37-17 LPF Toroids)
9V w/ WTST. 1.10 FW installed.
TN0110 finals instead of BS170, special heat sink added.
1N4148 Diode across L14?
Alternative USB Port (per Jeff Moore's note.)?
I measured a few of my toroids with capacitors and NanoVNA. Was getting higher #s than spec'd, more? than 20% higher. So ignored that initially, and built as manual suggested for the LPFs.? After seeing lower output on 15 vs 17, and 10 vs 12, removed some turns. This pushed things in the right direction, and tells me maybe my measurements actually weren't far off. I could go farther, but I'm happy enough with the output to stop here, especially if I mostly will use this unit at 8V and feeding a Hardrock 50.
Ended up with:
?
| ? |
LPFs |
Turns Suggested |
Turns Used |
| ? |
L2 |
21 |
20 |
| ? |
L6 |
21 |
21 |
| ? |
L3 |
12 |
11 |
| ? |
L8 |
12 |
12 |
| ? |
L4 |
13 |
12 |
| ? |
L10 |
14 |
13 |
Your results may vary, of course. Just my experience with this batch of toroids.
Power stats on 9V:? 168ma in receive. TX was 980 to 1100 ma, depending on band.?
Final power outputs, (lowest peak to peak value seen after 5+ seconds, into a QRP-Labs Dummy Load and a 200 mhz scope):
20M: 4.4w?
17m: 4.6w
15m: 3.8w
12m: 4.0w
10m: 3.9w
The heatsink: Wakefield LTN20069, $1.50 from Mouser. I drilled and tapped it for the 3mm screw a bit off center. It's 16mm square, and the original washer is 12mm. Needed to make sure it didn't hit the transformer. The TN0110s are reversed, so the flat part of the TO-92 case is against the heatsink. So went from 101 cubic mm of steel to over 1000 cubic mm of aluminum. It fits in the case with clearance.?
USB port; It does feel like a better fit than the supplied one, a bit more secure. This was another Mouser purchase for $1.20.?
?
Next up: Need to build a QRP-Guys SWR and Power meter kit, as well as their EFHW kit with tuner for 40-15m. Then I'll be trying to build a MidBand 40/30/20/15 QDX, and maybe 17M will work if I'm lucky.? The Midband, if it works, will be my POTA/Travel rig that I'd use with EFHW.?
?
-Nate? ?
N8BTR
?
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I have been using a repurposed server power supply for my shack.? ?They are very cheap on Ebay. I bought three of them. think I paid $20 each.? They provide up to 55 amps of power.? ?They're designed to be quiet and run 24/7/365.? They put out 12v but depending on the model can be modified to put out 13.8v.? I modified mine for 13.8v. Works great.?
For my QRP setup in just fine with a battery.?
73
Eric?
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Re: QMX and iPhone for digital modes
I have used the iFTx app along with a lightning connector to usb adapter to successfully operate FT4/8 with the iPhone and QMX.? The first adapter I purchased did not switch the audio path to the lightning connector.? I purchased a second one that included the audio path in the product description and it has worked well.? The VOX must be enabled in the digital interface menu on the QMX.? Here is a link to the adapter that has worked for me.
Roger KF9D
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Re: QMX and iPhone for digital modes
I have used iFTx with success on a QMX with .17 firmware and adapter cables for lightning to USB camera?and USB to USB C to plug into the QMX. I put a clamp on ferrite on the QmX end.??You have to set the radio for VOX.? Jay
On Tuesday, March 5, 2024, 3:56 AM, EA3IKB <drfletxes@...> wrote: Hi there,
?
Do you guys have found a way to do digital modes (FT8 / FT4) with the QMX and an iPhone, keeping the footprint at a minimum? What application in your iPhone are you using?
?
Even though CW is my main mode when SOTAs, I would like to also do some digital modes. I use my IC-705 connected to my iPad via wifi, which works flawlessly but I would like to reproduce this with my QMX and an iPhone.
?
Thanks for enlightening me!
73,
?
Joan
?,
?
Do you guys have found a way to do digital modes (FT8 / FT4) with the QMX and an iPhone, keeping the footprint at a minimum? What application in your iPhone are you using?
?
Even though CW is my main mode when SOTAs, I would like to also do some digital modes. I use my IC-705 connected to my iPad via wifi, which works flawlessly but I would like to reproduce this with my QMX and an iPhone.
?
Thanks for enlightening me!
73,
?
Joan
?
--
Jginaz
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Re: Faulty Progrock2 - no response to ticket
#progrock2
Peter -- in that case, and assuming that the ProgRock2 hadn't been connected to anything else either simultaneously or previously, and assuming that there was nothing wrong with the USB port or the cable (unlikely, of course), then there is little doubt that the ProgRock2 is defective.? I do think it's a rarity -- I've worked with a number of these and have a stock of at least 10 of them and haven't experienced any issues.? Other than submitting a ticket (which you have done already), or finding some other way of reaching Hans, I'm not sure what else you can do.? You could try opening another ticket?
73 - Steve, KW4H
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Re: QMX and iPhone for digital modes
There is an app called iFTx , but you have to pay for it. However, I ran into the usual Apple restrictions on data leads not recognised on my iphone/ipad.?
Best of luck.
73 Ken g4apb?
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Re: QMX and iPhone for digital modes
Joan,
I would also like to try iPhone!
73,
Bill
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QMX and iPhone for digital modes
Hi there,
?
Do you guys have found a way to do digital modes (FT8 / FT4) with the QMX and an iPhone, keeping the footprint at a minimum? What application in your iPhone are you using?
?
Even though CW is my main mode when SOTAs, I would like to also do some digital modes. I use my IC-705 connected to my iPad via wifi, which works flawlessly but I would like to reproduce this with my QMX and an iPhone.
?
Thanks for enlightening me!
73,
?
Joan
?,
?
Do you guys have found a way to do digital modes (FT8 / FT4) with the QMX and an iPhone, keeping the footprint at a minimum? What application in your iPhone are you using?
?
Even though CW is my main mode when SOTAs, I would like to also do some digital modes. I use my IC-705 connected to my iPad via wifi, which works flawlessly but I would like to reproduce this with my QMX and an iPhone.
?
Thanks for enlightening me!
73,
?
Joan
?
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hello all,,? Luc? when is the next QCX challenge?? ?
Scotty? ?Gi0bey
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WyleCoyote
Shirley Dulcey KE1L
Rick Williams - VE7TK
Don W3MW
John KY4WW
Eric K7EBR
Bill, N4QA/QRP