I have several Pills and the compiler reports all are 128K. The official 128K chip version is CB (I think), which looks very much lIke C8 unless you use a magnifier
Let? me know how you're making out using your Maple boards in Arduino.
Joe.
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When the boards are delivered and tested, I'll put the design files and Gerbers on GitHub. I'll also make the boards available to buy directly from the fabricator.
Joe
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Is there any interest in custom printed panels for the? ?? l added a fan to mine and printed a new back panel yesterday.? Which got me thinking others may want something similar.? Either like mine or changed for your specific build.   I posted about my first set here /g/BITX20/message/49117.? The front and back look the same it is just the lighting that is different.? I haven't given any thought to a fair price.? I would want to cover my cost and maybe have enough left over for a beer.? I print these with a .1mm thick brim so there is some flash/web to remove.? Fresh off the printer vs cleaned and ready to install would have some impact on the cost too.? Design time aside, these take about 3 hours each to print.? I can fit two on the print bed but it just doubles the time.? I print with the bed fairly hot which improves the finish but it also takes a frustratingly long time for the prints to be cool enough to remove without warping.? The face is smooth and glossy.? If you look very close there are faint lines from the printer bed and you might get a very small pit or dust inclusion.? I think they look great I just want give a fair description and manage expectations.? The inside is matte so it shows the printer lines more.? I print face down to get a good finish so the front has to be flat.? If you wanted something with protrusions I can do it but it will be matte and look like it came off a 3d printer.? I am currently only printing in PLA so these could get soft if you left them in your vehicle in the summer and it got really hot out.? For those of you that want to print your own I did upload blank panel stl files to the file section a while ago.? For the time being I will only mail to US addresses.? If you are interested please contact me off list or on list if you think your question or comment would be useful to everyone. Doug AC9RZ
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Re: UBITX filter bandwidth
I did see some online calculators for calculating the capacitor values.? Like you said it depends on the value of each crystal.? I don't think it is worth it for me to remove the crystals and do all the required work.
I though someone may have already done some work with filters of that kind and would have an idea' of about how much to change the values to get around 2 khz of bandwidth instead of the 1.6 khz I seem to? be getting.? ?Then there is the ripple and impedance that may or may not be worthwhile to worry about when doing this small move.
I have a lot of the smd capacitors and the hot air station to make changing it easy.? I just wish it was? going up in value as like you say it is easy to stack the components.
On Thu, May 24, 2018 at 6:21 PM, ajparent1/KB1GMX <kb1gmx@...> wrote: its easy enough to alter the capacitor values.? To what is a guess by anyone that answers
as your crystals may be different from someone else.
Try lowering all of them by 15% and remeasuring.? You will find out how it goes.
FYI 68 and 82 are standard values.? If you need odd non standard your take say a 56
and add a 15 on top to get 71 for an example.? When I say stack them SMT caps are
easily stacked like bricks.
The usual procedure to make a filter would have you measure all the crystals then grind
on the result and it will predict a capacitor value and terminating resistance.? ?And usually
when I do that I fixture it and measure it before stuffing it in a board.
Allison
_.
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Re: RF power chain mods and improvements..
WIlliam,
ITs missing a stage if you want to use 2n3904s at 10DB.? However if you use a higher frequency
(and likely a more costly) part that is not required.
Its about gain three stages at roughly 16DB is 48DB plus the finals.
Or you can do 5 stages at 10db each for 50DB and plus the finals.
What you cannot do is stages that start at 16db at 80M and fade to about
10-11db at 10M.? Its hard to get stable gain out of a device that is maxed out.
Doing that often icites instability and oscillation.
Allison
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Re: UBitx and case for sale
The UBitx and case has been sold.? Thank you all.
73
On Thursday, May 24, 2018, 11:43:12 AM EDT, Fr Richard R via Groups.Io <rickocr2005@...> wrote:
Sorry, my time is NOT open to outside things is what I meant...........
On Thursday, May 24, 2018, 11:41:14 AM EDT, Fr Richard R via Groups.Io <rickocr2005@...> wrote:
I have a new UBitx and case (from Amateur Radio Kits, Black) for sale.? The UBitx has new never been opened, parts bag still sealed.? The case is also new and never been opened, all parts still in original container.? I also have extra new TDA chips as the one on the board is the WX; I have Voltage Regulators of various types, new, in their case; a new HI-Per-Mite filtering kit, never been opened or assembled;? and a new Resister Kit with hundreds of new resistors! Everything you need to build the UBitx and make some mods!
As it turns out I will be unable to take the time to assemble these items as things have changed in my life and my time.
I am asking $220 for all which includes shipping.? I do not wish to sell separate.? In CONUS only, please.? I take paypal to my email address.
I purchased several supplies to get ready to build these kits, many were suggested by members of this group, and I thank you all for your patience and assistance.? My Church obligations have increased thus my time is open to outside things like kit building.
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I just received ?mine today and plan on getting it up and running just as it was shipped. Their are changes I want to make but for now I am going to put it on the air like it came. That ?is just what I am doing.
73's ?kn4ud ?
--
Allen ?Merrell
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Re: 6uH in BITX40 band pass filter?
#bitx40
My doubt is because the same pass filter of BITX40 should not have 6uH because the scheme says 40 turns on toroid T30-6. Apparently this does not affect you. On the other hand I thought it was a filter with a series tuned circuit but if you put 6uH in series with 100pF you get 6.497Mhz ...
Additionally Allison, this filter does not have variable capacitance.
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Please do not create a new topic for this every time you post.? I make it hard to provide answers
because we replied over in the other post.
You are not alone.
The problem is understood and people are working on it.? FOr now you can turn up RV1
if you need more power on 10M.
Allison
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Re: 6uH in BITX40 band pass filter?
#bitx40
LIke Arv said.? and if its low or high spreading to closing the turns will move the value some.
All you care is the frequency of resonance.? You can tweak the cap soem to make it work.
Allison
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W3JDR ?
Thanks for sharing, this is somthing I would be interested in. I have a maple mini and it does have the 128k but the blue pills I have are C8's ?and are 64k . ?I have seen articles where the C8 ?chip was programmed with the option in the arduino for the 128k ?and it worked fine. I downloaded ?your files and with a quick look they look very nice. Again, thanks for sharing.
73's and have a great vacation . kn4ud
--
Allen ?Merrell
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Re: UBITX filter bandwidth
its easy enough to alter the capacitor values.? To what is a guess by anyone that answers
as your crystals may be different from someone else.
Try lowering all of them by 15% and remeasuring.? You will find out how it goes.
FYI 68 and 82 are standard values.? If you need odd non standard your take say a 56
and add a 15 on top to get 71 for an example.? When I say stack them SMT caps are
easily stacked like bricks.
The usual procedure to make a filter would have you measure all the crystals then grind
on the result and it will predict a capacitor value and terminating resistance.? ?And usually
when I do that I fixture it and measure it before stuffing it in a board.
Allison
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Re: uBITX - Digital mode power variation with input frequency
#ubitx
#ft8
If you are operating at 7070khz, and you feed in an audio tone of 1000hz, the rig will output rf at 7071khz to give you an idea.
The SSB filter operates at AF, but it is relative to where the oscillator is operating. Least thats the best sense I can make of it.
If this reply seems off, I apologize, I am missing emails here and there from this thread.
Sorry to be such a novice, but is that 1600-1700 centered around a particular frequency?
--
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N5WLF, Greggory (or my nickname, Ghericoan)
General Class, Digital Radio Hobbyist
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Re: uBITX - Digital mode power variation with input frequency
#ubitx
#ft8
Sorry to be such a novice, but is that 1600-1700 centered around a particular frequency?
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Re: 2 meter bitx possible?
Arv,
You have it nailed.? THe 2n3904 would have an effective gain of maybe 2.
I've done a few and generally the RX side is easy for SSB.
The base receiver and SSB generator side flies well enough to clone.
The mixer from 2M to 45mhz IF needs to be better too.? Add a RX rf amp.
The side from the relays over to the edge would have to be new and must use more costly
parts to hits a 10W level (enough to be sporting on 2M).? It would not do AM or FM.
About 90% of the design effort would be the TX amps and filters so they are either
easily tuned or no-tune.? We are not talking a 100$ radio anymore.? ROM would be
295-400$
I can see why as 2M rigs make a good transverter radio for 432 and up into the microwaves.
For that 3-5mW is enough and a pair of MAV-11s would do fine to that power and a
MAR6 or 8 for the RX preamp.? FOr that power level its a cheap design.
Save for I know of no one taking or making a list.
Allison
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Has anyone tried to increase the bandwidth of the ubitx filter ?? Mine is about 1650 Hz wide at the 3 ot 6 db points. I would like to get it to about 2 to 2.2 KHz wide.? I am thinking about reducing the 100 pf capacitors to around 60 to 80 pf.? From what little I know about the filters, this should widen it out some, but may cause other undesirable changes.
de ku4pt
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Re: uBITX - Digital mode power variation with input frequency
#ubitx
#ft8
I have made some rough measurments and found the filter to be about 1600 to 1700 Hz wide.? If one wants to just the digital then the BFO frequency can be moved about 200 to 300 Hz to get the power up at the? higher audio frequencies.
?
On Thu, May 24, 2018 at 5:23 PM, Tim Gorman <tgorman2@...> wrote: This is because of how narrow the SSB filter is. Once you begin to move
out of the passband your power output will drop. The filter in the
ubitx is pretty narrow. It's not surprising you see a drop-off after
1600hz.
tim ab0wr
On Thu, 24 May 2018 10:57:27 -0700
"Robbie Robertson" <robbie.robertson@...> wrote:
> I'm new to uBITX, but used to operating digital modes (including
> FT8), but I'm not sure if what I'm seeing is a fault, or normal for
> the uBITX... I'm using WSJT-X, and when I TX on the lower end of the
> 'spectrum' I get a much higher power output that the higher end
> (sorry I haven't got a power meter, but I can see the current being
> drawn from the power supply changing, and also the signal meter on my
> FT767 with no antenna attached). This is strangely, the complete
> opposite I get when operating using the FT767 (i.e. high power at the
> higher end of the audio range).
>
> Has anyone else experienced this,, or has a view on how to address it?
>
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Re: uBITX - Digital mode power variation with input frequency
#ubitx
#ft8
This is because of how narrow the SSB filter is. Once you begin to move out of the passband your power output will drop. The filter in the ubitx is pretty narrow. It's not surprising you see a drop-off after 1600hz. tim ab0wr On Thu, 24 May 2018 10:57:27 -0700 "Robbie Robertson" <robbie.robertson@...> wrote: I'm new to uBITX, but used to operating digital modes (including
FT8), but I'm not sure if what I'm seeing is a fault, or normal for
the uBITX... I'm using WSJT-X, and when I TX on the lower end of the
'spectrum' I get a much higher power output that the higher end
(sorry I haven't got a power meter, but I can see the current being
drawn from the power supply changing, and also the signal meter on my
FT767 with no antenna attached). This is strangely, the complete
opposite I get when operating using the FT767 (i.e. high power at the
higher end of the audio range).
Has anyone else experienced this,, or has a view on how to address it?
btw - I'm using a Easi Digi interface to feed PC headphone socket
output into the mic socker connection (no mic attached).
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Re: 6uH in BITX40 band pass filter?
#bitx40
?A? ldrich
?I would use 41 turns to start with.? That way you can easily remove one turn if 41 turns
is too much.?
Arv? K7HKL
_._
?
On Thu, May 24, 2018 at 3:04 PM, Aldrich Sarmiento <aldrich.sarmiento@...> wrote: Greetings, I'm about to start building a BITX40 with the dead bug style and I've noticed that the filter passes band indicates 6uH however 40 laps on a toroid T30-6 is 5.76uH, not 6 ... I mention this because in my toroids I have 5.8uH and if I give it one more lap I have 6.2uH. So, which one do I use?
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Ghericoan
Robbie Robertson