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Re: Instruction Manual needs revision
#ubitx
I have attached my first pass at the "MBITX TUNEUP" instruction, and welcome your comments.? I have aimed for ease of understanding, particularly for newcomers to our interesting hobby.?
-- Jon Titus, KZ1G Herriman, UT USA |
Re: Variable Power Out
¿ªÔÆÌåÓýPut a pot in between the audio from the computer and the mic input to the radio. Then you can adjust for the desired level. ?Alternatively check to see if you can control the output level, either from the software or the computer¡¯s volume control.Clark Martin KK6ISP
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Re: Nextion Display
I have a 3.2 ordered and waiting for it to arrive. I am using the 1.08CEC firmware from Dr. Ian and like it a lot. I am adding 8 switches to it. I know the manager has options for 6 but I am adding one for FKEY and momentary toggle for PTT. I would appreciate any information I can get on the Nextion Display. I downloaded the software on the Nextion site but have not loaded it yet to check it out. Thanks Dr Ian for all your great work.
73's kn4ud kn4ud@... -- Allen ?Merrell |
Re: LCD Interface Question: Parallel or I2C?
#bitx20
#bitx40help
#firmware
yes...it frees up 6 i/o lines On Sat, Jun 2, 2018 at 3:04 PM, Allen Merrell via Groups.Io <kn4ud@...> wrote: I2C frees up some pins. I2C only uses 2 pins plus power and ground. This was my reason to go to I2C. --
Paul Mateer, AA9GG Elan Engineering Corp. NAQCC 3123, SKCC 4628 |
Re: LCD Interface Question: Parallel or I2C?
#bitx20
#bitx40help
#firmware
I2C frees up some pins. I2C only uses 2 pins plus power and ground. This was my reason to go to I2C.
73's kn4ud -- Allen ?Merrell |
Re: ?BITX Disable TC (use for CW training)
Yes. The firmware is backwards compatible. - f On Sat, 2 Jun 2018, 19:12 Hans Stoll, <tool4fish@...> wrote: On Sat, Jun? 2, 2018 at 06:41 am, Hans Stoll wrote: |
Re: uBITX physical comm port - newbie question
Tom Francis
¿ªÔÆÌåÓýThanks for the quick reply - I really appreciate it.I do some QRP building and experiment a little, but I've never gotten into the micro controller scene much at all other than reading up on it.? 50 some years of playing radio I'm still something of a Luddite. I will do what you suggest - looks like fun. Thanks again. Best regards, Tom, W1TEF On 6/2/2018 1:55 PM, Ralph Mowery
wrote:
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LCD Interface Question: Parallel or I2C?
#bitx20
#bitx40help
#firmware
As hams have hacked or modified their uBITX transceivers, some have moved to a 4-line LCD controlled via an I2C connection.? The electrical connections with a 2x16 or a 4x20 LCD look the same, so why the need for the I2C interface?? It would seem easier to simply change the display addresses and use the standard interface.? Could someone explain to this newcomer why I2C offers advantages or if some incompatibility exists between the display types.? Thanks.?
-- Jon Titus, KZ1G Herriman, UT USA |
Re: uBITX physical comm port - newbie question
¿ªÔÆÌåÓýThank you very much.? Appreciate it.Best regards, Tom - W1TEF On 6/2/2018 1:47 PM, Ralph Mowery
wrote:
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Re: RF power chain mods and improvements..
On Sat, Jun 2, 2018 at 09:48 am, Arv Evans wrote:
Yep and everyone we to adding a preamp or compressor.? What they are trying to fix is the output of the 45mhz mixer is very low and even at 80m the power amp if run that way puts out about 10W.? Move up to 40M or 20M where the power amp has less gain and people drive the audio harder and you get 7W.? NOt a problem yet as the low pass filters are adequate. At 21mhz the game is worse, less gain and less power and more audio gets used and now the filters are wide open.... FYI the output of that mixer is clean at -19dbm after the 30mhz filter.? That means to hit 10W you need 59DB of gain.? The base amp on 80M maybe does 62db wide open. at 40M that drops under 55....? and at 10M your stock amp chain gain is maybe at 45db or about 50 (maybe 100) milliwatts so if your seeing more its audio push to make up for it.? How much push at -11dbm? the spur is less than 30db down (V bad!) and your getting 1.7 to 2W.?? With a highly modded TX we get to 3w, turn up the mic gain and 10W and that spur at 16mhz is now about 20-50mW!? That is the problem!?? Also audio gain controls would be turned up anyway, its just one more mis-adjustment. Of ten radios built by me and on the air only one has a mic gain, its there because the hole was there first in a reused box. Once set it has never moved.?? Allison |
Re: Power supply question
¿ªÔÆÌåÓýThe LM1085-12 has a dropout voltage of 1.3v typ; 1.5v max.?? The lm1117ADJ likewise has a low dropout voltage but would require a couple more parts since that part doesn¡¯t come in a fixed 12v version. Mike K5ESS ? From: [email protected] [mailto:[email protected]] On Behalf Of Bo Barry ? If I recall correctly the 3 terminal regulators definitely need a minimum of 3 volts difference between input and output. |
Re: uBITX physical comm port - newbie question
Before playing too much with it, you can get just the Arduino processor and play with it.? They are only about $ 2.50 from China off ebay if you don't mind waiting 3 or so weeks.? This is what I bought a while back to do some playing.? There are 5 of them for about $ 12, but you can find single lots of them. Notice the silver thing on the left.? That is the USB connector you are looking for.? They can be powered by just the usb connector plugged into the computer if you just want to play with the programming of them.? Same with the ubitx.? The display will light up and you can program it through that connector, but the rest of the ubitx will not be powered.?? de ku4pt. On Sat, Jun 2, 2018 at 1:19 PM, <ubitx@...> wrote: First, thanks for letting me join - appreciate it.? The question I'm asking is pretty simple, but I have no experience with this at all.? I've put my uBITX together and it works - really cool too I might add. I looked around, but I can't find any installation instruction or guides with respect to putting the physical USB Comm port connector into the uBITX. Any help with this would be greatly appreciated.? Thanks for you patience with a newbie.? Tom, W1TEF |
Re: uBITX physical comm port - newbie question
With the display facing you, turn it so you cal look into the right side of the display between it and the board behind it.? You will see a small USB connector facing you . .? Forgot what it is called , maybe a mini USB.? Any of the usb cables that fit will work if you are sure you have a data cable.? Some cable are just for charging the batteries of a cell phone and only use 2 of the 4 wires in the USB cable. You will need a program to see anything out of this port on the computer.? Go here: for free software .? Arduino 1.8.5 seems to be the latest Windows software for it. This is the home page for lots of info on the Arduino processor. 73 de ku4pt On Sat, Jun 2, 2018 at 1:19 PM, <ubitx@...> wrote: First, thanks for letting me join - appreciate it.? The question I'm asking is pretty simple, but I have no experience with this at all.? I've put my uBITX together and it works - really cool too I might add. I looked around, but I can't find any installation instruction or guides with respect to putting the physical USB Comm port connector into the uBITX. Any help with this would be greatly appreciated.? Thanks for you patience with a newbie.? Tom, W1TEF |
Re: Han's fabulous article on the QCX
While I've not used the QCX I know its progenitor the KK7B MiniR2, R2pro, MicroR2
very well and yes?the direct conversion image rejecting RX sounds very very good. I've useed that for SSB TX too. The need for quadrature LO has always been an issue with those and generally a pain of done analog. A decade back I did a design using miniR2/T2 as an upconverting 6M radio. The uR2 works as well at 1mhz as 200 same performance.? So why not use it?? at higher?? ?No reason not to.? While its full analog its not hard to get I/Q? LO right when its fixed.? Sideband selection is at audio.? Narrow filters, do it at audio. In process is a HF upconverting radio using the microR2/MicroT2 ?as the IF (basically half the uBITX) with one mod rather than running them with a VFO at 40M I moved them to?36mhz(fixed) and upconvert to that.? As a wide tuning RX its simpler than uBitx as only two oscillators are needed and one can be a crystal as its a common frequency.? The other is one conversion.? For TX I did not go wide band as I only wanted to TX on the standard bands (80,40,20,15,10) so band pass after conversion and lowpass on TX. How this is relevant.? My experience with 36mhz down converting TX showed the image and spur issue and filters were planned anyway so it was a not a lock out.? However moving the micrR2 and T2 to 64mhz or higher is fairly trivial as its a fixed frequency and 64mhz crystals (for the LO) are common or the Si5351.? ?With that in place and some simplification a wide 1.8-30mhz tuning upconverting TRX is now a known thing.? No crystal filters and a whole lot less RF hardware.? Its superhet but bridges the usual issues of mushy filters and tuning the IQ LO.? The 5351 solves the issue of a lo from 64mhz to 94mhz. While those radios were specifcally for SSB based work CW can be done the same way as the ubitx, inject DC into the TX mod and carrier out. Add sidetone and move the TX frequency (down converting LO) for the correct offset and go. The QCX is an example of how non-superhet radios can make inroads when? the quadrature LO or any LO solution is as simple as a Arduino and 5351. Some would argue code is complex but once done its always reusable. Rick Campbell and Dan Tayloe and others gave us a better set of tools to solve the issue. Allison |
Re: PTT Question
Lawrence Macionski
Not to start an "oil thread" = motorcycle & aircraft? bloggers go on for months each time someone says "what about oil?" |