On Fri, Aug 31, 2018 at 10:41 AM, Lawrence Galea wrote:
Google?picatune ATU
I dust did. An interesting article with lots of good information. Tom, wb6b
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He is getting a laser cut acrylic version. I offered to print a few if he provided the material to produce the object . Instead they went with laser cut acrylic.?
Ill get s copy of that object in case it comes up again and some one is ok with white or whatever color I happen to have.?
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I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??
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Re: CW PTT attack time to slow
#ubitx
On w0eb.com webpage is NANO software that implements interrupt driven CW generation.? Also
eliminates the voltage divider scheme.? Also eliminates the need to switch between straight key
and paddle as both are always active.
rOn
On August 31, 2018 at 9:41 PM ajparent1/KB1GMX <kb1gmx@...> wrote:
Joop,
IF you don't mind grinding code where are many possible fixes.
I would suggest looking at V4.3 as it is a bit cleaner and more current.
The biggest issue is the software is a big loop and CW ke is checked
a few times in the loop.? Speeding up the loop is one thing.? Or making
the input interrupt driven so when there is an event it gets the processors
attention.
Allison
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Re: UBITX V3 TX GAIN VARIATIONS
I'm convinced Hans did a good job.
Especially after seeing this in his post:
? "I am very grateful to Allison KB1GMX for her advice, encouragement, support and testing during the development of this Linear PA."
I'll be buying that amp, once Hans starts selling it..
Then cut off the back half of my uBitx with a hacksaw.
I had thought of the BS170 in regard to the uBitx in months past,
but figured it might be too lightweight when used as a linear.
And didn't fancy dealing with two more bias pots.
Will be interesting to see how Hans went about it
> Bag, cat, QSX amp.
I've heard of bag phones, though not bag HF linear amps.
And radio has been explained through the metaphor of a very long cat (or lack thereof)
But still seems a bit cryptic.
Jerry, KE7ER
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On Fri, Aug 31, 2018 at 06:20 PM, ajparent1/KB1GMX wrote:
Jerry,
If you have been reading I've mentioned I have several amps that actually do work...
Bag, cat, QSX amp.? I've been beating the crap out of one and its by far one of
the most solid designs to date.? Simply put, its that good.? For those that say?
it can't be done the answer is its done at last count everyone of the ones built
in SA YOTA 2018? its not a fluke.
Hans did some fine work.
Allison
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Re: UBITX V3 TX GAIN VARIATIONS
Jerry KE7ER,
The key to make it fly is layout to avoid ground loops and parasitics and
attention to cooling and that includes the BS170s.
There are pictures of his board. and for that fact the Softrock.? Many devices will
tolerate high peak power if a little attention is given to cooling.
The reason the amp works well is the BS170s aren't being flogged to drive the IRF510s.
and both with care have enough gain for the task.? There is ample headroom as 10W
needs about .5W from them and they can do 1W.
It did run at 10W swept frequency for over an hour.? I was interrupted and forgot it,
while I was doing something else.? At the 10W power level I've not yet found anything
that kills it.? Even when running into reactive loads.
Allison
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Re: CW PTT attack time to slow
#ubitx
Joop,
IF you don't mind grinding code where are many possible fixes.
I would suggest looking at V4.3 as it is a bit cleaner and more current.
The biggest issue is the software is a big loop and CW ke is checked
a few times in the loop.? Speeding up the loop is one thing.? Or making
the input interrupt driven so when there is an event it gets the processors
attention.
Allison
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Jim,
>>one other thing on the Elecraft T1 autotuner. ?I remember something that Wayne Burdick, N6KR (Elecraft founder and CEO) said about the T1. ?During initial testing of it, he messed up and accidentally hit it with 100 watts for a brief period (It's spec'd for 20W CW max) and it survived. ?Of course, this isn't recommended but it speaks well for Elecraft's product quality.??
Mine has survived accidents to much more than 20W.? And now the rest of the story... cockpit error... Running
QRP SSB QSO and we were getting fading on 40 so I hit the switch for the EBY amp (about 50W) and all was happy.?
Moved to 20M even remembered to change the band switch on the amp? and without thinking hit the T1 for
re-tune for 20M at about 50-55W,? it got weird and stopped with a bad match.? ?Reason the forward SWR detector
diode died.? The coils and caps can take it and tolerates a bit of abuse just don't tune at high power.
So yes I can recommend it and with no reservations.?
One of the best products I've built as a kit.
Allison
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Re: UBITX V3 TX GAIN VARIATIONS
On Friday, August 31, 2018, 3:11:21 PM PDT, ajparent1/KB1GMX <kb1gmx@...> wrote:
On Fri, Aug 31, 2018 at 12:41 PM, Jerry Gaffke wrote: Allison
_._,_._,_
Imma gonna put this here, tho it really does not apply to either the post I'm replying to or the "gain variations" as such If you want to know why the ubitx is generating all the "cruft" in the finals, look at the schematic especially L9 and L10. Both are wound on ferrite cores ..Both have DC current flowing through them ..According to the rev. 4 schematic they are supposed to be 60 uH ...I measured the ones I removed from my radio 23 uH ...just for fun, i monitored the impedance variation through them while passing DC current through them? O ma current, 23 uH ...5 ma current gave 15 uH ...10 ma current gave 11 uH ...since these inductors pass 100 mA (according to the setup procedure ...who knows what the inductance is under operating conditions ...Flowing DC through a ferrite biases the magnetic domains in the ferrite ...Maybe it goes back most likely not....ANY ferrite us susceptible to permeability change under the influence of a DC biasing current ...Its doubtful your "spice" analysis will account for this .. Make the finals look like the WA2EBY unit....Clean up the finals, then go chasing the remaining spurs (there are a few left I noticed)
Jim
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Re: UBITX V3 TX GAIN VARIATIONS
Jerry,
If you have been reading I've mentioned I have several amps that actually do work...
Bag, cat, QSX amp.? I've been beating the crap out of one and its by far one of
the most solid designs to date.? Simply put, its that good.? For those that say?
it can't be done the answer is its done at last count everyone of the ones built
in SA YOTA 2018? its not a fluke.
Hans did some fine work.
Allison
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Thanks, ? David A Posthuma, WD8PUO 1 (616) 283-7703 ?
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From: [email protected] < [email protected]> On Behalf Of Gary Hanson Sent: Friday, August 31, 2018 9:00 PM To: [email protected]Subject: [BITX20] 4.2¡± Nextion Bezel? ? David, Here is a two step process to get a black plastic bezel for your Nextion display. First, go to the ITEAD website and down load the 3d bezel zip file for the size of your display and unzip to your desktop. Go here:?
Next, go to??and?go through their order process that requires that you upload the file from step one above. ?You will need to indicate the color and the material you want to print with. I went with the cheapest and looks great. ?The 3dhub company has great customer service. Mine cost $9 including postage and took about 10 days. ?Hope this works for you. ?
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David,
Here is a two step process to get a black plastic bezel for your Nextion display.
First, go to the ITEAD website and down load the 3d bezel zip file for the size of your display and unzip to your desktop.
Go here:?
Next, go to??and?go through their order process that requires that you upload the file from step one above. ?You will need to indicate the color and the material you want to print with. I went with the cheapest and looks great. ?The 3dhub company has great customer service.
Mine cost $9 including postage and took about 10 days. ?Hope this works for you.
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Karma for not building an AM-FM radio design? (as per your group designator ). ??
Karma that is coming for making Irrelevant and meaningless posts on a technical forum ? and perhaps doing a bit of self promotion in the the process.?
Karma for? trying to design and build a multiband radio outside of Japan/PRC .??
What does the comment mean ??
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Re: UBITX V3 TX GAIN VARIATIONS
Hans let the cat out of the bag here:?? ? ? /g/QRPLabs/message/26092He's using a couple BS170's in push-pull to drive the IRF510's on the QSX. They look ideal. Ideal in that they approach $0.05 each in volume. I've got a bunch of BS170's here, bought for spares in my ATSprint and MTR rigs from KD1JV. He ran 3 in parallel, got a bulletproof 5 Watts out in class E for CW. Apparently, a push-pull pair of BS170's can give over a Watt in linear service as used in the Softrock Ensemble RXTX: ? ?? Note the curious circuit around Q4 and Q5 for setting the gate bias voltage. Q5, Q7 and Q8 should be matched for similar Vgs. Jerry, KE7ER
On Fri, Aug 31, 2018 at 03:06 PM, ajparent1/KB1GMX wrote:
MRM,
Actually I¡¯ve been doing a lot of experimentation on flattening/ linearizing the transmit chain.? The parts I¡¯ve fallen on are the NE46134¡¯s.? They have plenty of gain, Ft of 5 GHz, and with the proper inter stage transformer design¡ An almost flat (-0/+0.6 dB) frequency profile swept from 0.5-60 MHz is possible.? I suppose prototyped, it isn¡¯t much of a uBITx though.
Good part one of many that will work.? The right device and the right transformer,
The other third of the story is layout.??
Allison
?
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Re: VK4PP uBitx LPF BANK add-on Board
perhaps my terminology wasn't clr.? Relay in resting state:
Loss from 12 to 16 (NO contact, uBITX pinout) is ~ -34dB at 30MHz
Loss from 12 to 1 (to NO contact of the opposite side) is ~-39dB
Loss from 12 to 5 is ~-33dB
Loss from 12 to coil ~-52dB
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Re: VK4PP uBitx LPF BANK add-on Board
Losses in dB are additive.
So loss from pin 12 to pin 16 is 40-32 = 8 dB when pin 16 is open?
That would be killer, doesn't seem right.
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On Fri, Aug 31, 2018 at 03:11 PM, Glenn wrote:
Gordon, the Common terminals being 5 & 12 in the uBITX Sch numbering scheme, -32dB
Approx -40dB from Common one set (5)? to the NO contact on the other contact set (16)
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Just to add to what others had to say about the T1. I¡¯ve built and used it with both an EFHW and a 40 meter Gap Antenna and it works great!
Guy WB7SZI
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Re: UBITX V3 TX GAIN VARIATIONS
On Fri, Aug 31, 2018 at 12:41 PM, Jerry Gaffke wrote:
Parts do not come with solder on the pins.
When manufacturing, the usual process is to lay a stainless steel mask over the board with holes cut into it for each pad,
then squeegie on some solder-paste, which is solder with the consistency of play-dough.
Then auto-insert all those dinky R's and C's and transistors with a pick-and-place machine.
Send the board through a heat process of some sort.
Your right but most part have either tin or gold plating that takes solder like a fish to water. It takes very little added material to stick them down. Me I use really fine solder 0.020 and a moderate tip iron maybe .12"? unless then are very close to each other its nothing.? ? I can lay down parts very fast.? Come with practice. Having a "thumb" (check around the net for ideas) can be handy for some parts. Allison
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Re: VK4PP uBitx LPF BANK add-on Board
Gordon, the Common terminals being 5 & 12 in the uBITX Sch numbering scheme, -32dB Approx -40dB from Common one set (5)? to the NO contact on the other contact set (16) Picture is between common terminals as above. Typical curve of standard relays. 
On Sat, Sep 1, 2018 at 02:17 AM, Jerry Gaffke wrote:
I interpret this measurement from Glenn:
? ? "-32dB from one set of contacts to the other. (common terminal)"
as being from KT1 pin 14 to pin 16 as seen in the uBitx schematic.
Also, interpret his -39 and -41 dB numbers to be from one relay section to the other,
which I averaged as -40dB.? ? For example, KT1 pin 12 to pin 5.
I now suspect those assumptions are incorrect, but the analysis could easily be adjusted to for any change to those two numbers.
Jerry
On Fri, Aug 31, 2018 at 03:40 AM, Glenn wrote:
All good points Warren.?? I did some checks of isolation using a typical DIP relay, type HK19F. DPDT
I made a small jig to hold the relays and measure isolation across contacts etc.
Typically it was -34dB across open contacts,
-32dB from one set of contacts to the other. (common terminal)
-41dB from open terminals on each side
-39dB from common of one pole to open on the other pole.
-48db from common to coil.
?At 30MHz.? Better as freq drops of course.
That's without effects of a PCB and various other traces.
glenn
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Re: UBITX V3 TX GAIN VARIATIONS
MRM,
Actually I¡¯ve been doing a lot of experimentation on flattening/ linearizing the transmit chain.? The parts I¡¯ve fallen on are the NE46134¡¯s.? They have plenty of gain, Ft of 5 GHz, and with the proper inter stage transformer design¡ An almost flat (-0/+0.6 dB) frequency profile swept from 0.5-60 MHz is possible.? I suppose prototyped, it isn¡¯t much of a uBITx though.
Good part one of many that will work.? The right device and the right transformer,
The other third of the story is layout.??
Allison
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David Posthuma