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Finally fixed it. I don't recall using the old bootloader earlier and I thought the hex loader might have disturbed it since I could no longer upload sketches.?
Long story but all is well when I selected old bootloader.

Never did find the compiled hex files but going from source worked fine for my 20x4 display.

Fun project for sure.
W4GHV?

I'm not so sure that a high SWR is more likely to kill an IRF510.
What characteristic of the RD16HH1 would make it a better survivor?
If we are talking a missing antenna, it's voltage spikes that would kill the final.
An IRF510 is good for double the voltages that an RD16HH1 is.

I haven't thought very much about what happens when an antenna is shorted to ground.

Here's an old thread about voltage spikes at the final:
? ??/g/BITX20/message/41057
I'm not very handy with magnetics, but my conclusion there is that T11 on our push-pull
uBitx final is a forward transformer, behaves like any filament transformer.? Energy is
coupled through the transformer, not stored in the core.? The center tap of the primary
is at 12v, when one side of the primary is shorted to ground by a FET the other side
will bounce up to 24v.? And one or the other FET is always on.
?
On the Bitx40 with its single IRF510 FET and inductor up to VCC, we are alternately storing?
energy in the core when the FET is on, then releasing that energy when the FET is off.
This is a flyback transformer, the configuration is that of a boost mode switching power supply.
With a high impedance antenna there's nowhere for that energy to go, we can expect some very high
voltage spikes.? But my simulations were showing that at 7mhz and no antenna those spikes
weren't all that bad.? As the drain voltage rises it drags up the gate (miller capacitance)
and keeps the FET turned on.? If you bring the frequency down far enough from 7mhz
the FET does eventually turn off, and you?start seeing kilovolt+ spikes
at the Bitx40? FET drain in the simulation.?

Is Gary, N3GO still around?
I wonder how that TR scheme of his worked out.

Jerry, KE7ER

1) ?I deleted the latest version (v1.4) of the Chinese ch341 driver
2) ?Restarted
3) ?Purchased and installed the mac-usb-serial.com ch341 driver for OS X 10.12
4) ?Restarted, debugged and tested for several hours per the mac-usb-serial.com instructions.
5) ?As a last hail Mary, I set the options under the Arduino Tools Menu to - Processor: ?Atmega328P (Old Bootloader)
6) ?It worked! ?I set the Arduino Preferences to Show verbose output during upload.
7) ?Restarted and tried again. ? It still worked. ?

It is interesting that I do not have to select ?- Processor: ?Atmega328P (Old Bootloader) on my old MacBookPro to get a good upload.

This is only a temporary fix. ? There is an entirely different mac-usb-serial.com driver already released for OS X 10.13. ?When I upgrade to 10.13 the current driver will need to be removed and the new one installed. ?I expect everything to break again for other future OS updates.

I am still avoiding CH34x chipsets like the plague. ? They are very high maintenance if they work at all. ? So please no more products with CH34x chipsets! ? Mac users everywhere will thank you. ?

Thanks to?Andrew? VK6WAM ? for the link to?.

73?
AB2TS

On Sat, Apr 28, 2018 at 04:06 pm, Andrew Merrybard wrote:

Just as an aside. I am having good luck with he drivers for the CH340 (etc) from

?.

Just the mac-usb-serial drivers, ?same problem. ?Radiuno fails to upload. ? NodeMCU works....

Radiuno continues to work with an antique MacBookPro

I've been looking at the ND6T website and find several interesting, useful, and focused on minimalist circuits.?

1) The AGC circuit which we're discussing here. I have a board layout which is 980mils x 980mills and it seems to fit nicely. It offers jumper selection of 4 Hold times and AGC OFF......using 0 ohms for AGC OFF, "a" ohms, "b" ohms, "c" ohms, "d" ohms. It's a 2 sided board which you can attach with double sided tape to the back of an RF gain pot (5K) or wherever you want. The reason for mentioning the RF gain pot is that it's a recommended good idea and you wire it to the uBITX board using small coax. This is also explained by ND6T in the "Adding an RF Gain Control to the uBITX".

2) T/R Click Fix is a board half the size of the AGC board and contains the circuit defined by ND6T. I refer you to his write-up for implementation.?

3) The Polite Antenna Tuner also caught my eye and has a really simple minimalist technique using a broadband noise generator to tune the antenna and listen with your receiver for a null (when you are matched to 50 ohms). Seems to fall right in line with QRP rigs and tuners. And you don't require transmitting to get "close". Believe you me, a high BITX antenna SWR will take out an IRF510 in a heartbeat .....not so much for a RD16HHF1 RF MOSFET. Sounds like another ~ 1 sqin board.?

73 Kees K5BCQ

I have a new uBitx that seems to be working fine except for the microphone. I am using several electret mics that I know work as I use them on my computer, hand held Baofeng, ICOM 746, etc with no issues at all except for the microphone output. In LSB on 40 meter I have no output on LSB or USB. CW works fine as it should with the straight key. I have tried the stock sketch as well as the KD8CEC 1.061 sketch. Both have the same characteristics. When the PTT is depressed, the LCD indicates the unit is going into TX mode, there is lots of speaker pop both on depression and release. However there is no output on my meter. I can go to CW mode and get a full 7 watts out. d
I have checked the wiring about a dozen times and am getting 1.4 vdc on the violet wire which is hooked to the tip of the mic connector and the blue wire is hooked to ground. The mic I am currently trying to use is a Kenwood speaker mic I use on my Baofeng. It works fine.

Suggestions, ideas, comments?




--
72 and God bless
KD4EPG

It is interesting that the Chinese driver recognizes a CH340 NodeMCU via the Arduino GUI, but it crashes on my CH341 Radiuno.

I am getting quite good at installing and removing the driver kext files. ??

I'd rather be programming my Radiuno.

Hello

Anyone tried to run RTTY with their uBitX? Or how this working?

I will get mine in few days, so looking forward to get it :)

Best Regards,
Stein-Roar Brobakken
post@...
LB3RE K3RAG
Skype: lb3re.rag

--

开云体育

At this point I have no intention of using my ?BITX for CW.? I understand I still need the pull up resistor between pins 2 and 3 on the Raduino.? I am trying to eliminate as many unnecessary wires as possible.? Couldn't I just connect a 4.7k resistor between the pins without using the jack or am I missing something?

So far I have to say the Han's QCX concept is really neat. It uses 6 passive components and provides an on-board DC, AC/RF meter, RF power meter, frequency meter and signal generator. Brilliant.

That coupled with the measuring functions pre-loaded in software and an expected list of values seems the best value for money in debugging a radio's circuit and wiring.

The spare A7 input could be put to fair use in the wiring phase of the project before being used for whatever the user feels like.

In my view if the Arduino is not functional, then there is not much to test since the radio would not be functional. So this is assuming the Arduino is at least communicating . And if it is, but has defective analogue or digital input failures then one side value of the test would be to determine if the pain of going through its replacement is warranted or not.

But as suspect, recollecting the list postings, that wiring issues and possibly alignment issues are main problems so far.

The test software will be small enough to fit alongside the factory firmware if it is deemed of value. That and a few components could be of great value imho.

And a pre-loaded software would avoid what could be seen as a daunting task of setting the Arduino IDE and loading a software.

In the mean time, I'll keep coding and see how much we can extract of the current hardware.

All the best,

73, John (VK2ETA)

Check the wiring at the potentiometer. I indeed reversed two of them, so as switched on the volume was highest. Maybe that was one cause of the failing TDA without the WX mark. Volume is plenty as there is no agc when signals are strong.

I agree with you. I have one on order.

If you already have a good IF system (i.e. the ubitx) why spend money
duplicating it?

tim ab0wr

On Sat, 28 Apr 2018 10:06:06 -0500
"K9HZ" <bill@...> wrote:

If such a radio is just CW and SSB, those ultra-cheap transverters
from the Ukraine are by far the best solution. If the radio will
operate FM… that’s where a redesign is required.



I’m using one of the transverters now and they work fine with some
simple interfacing.





Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ
PJ2/K9HZ



Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois



Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com <>

Like us on Facebook! <>



Moderator – North American QRO Group at Groups.IO.



email: <mailto:bill@...> bill@...





From: [email protected] [mailto:[email protected]] On Behalf Of Jerry
Gaffke via Groups.Io Sent: Saturday, April 28, 2018 9:58 AM
To: [email protected]
Subject: Re: [BITX20] mono band 2 meters rig based on the micro BITx
circuit #ubitx #2meters



Looks like the goal is to build something more challenging than the
uBitx. Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of
SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an
si5338 or si5341? Having all oscillators off a single reference makes
calibration much easier. Could be used for cross band ops if it
receives on more bands than it transmits. A wideband receiver could
also be a spectrum analyzer, use digital techniques on the audio when
resolution better than the crystal filters is required. Transmit
mixer, drivers, final could be a separate board for each band
desired, zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:

I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you
thinking a two-band unit or one-band unit?





---
This email has been checked for viruses by AVG.

For me the easiest thing to do would be to have a socketed Nano (I
know - cost!). You could then plug in a second Nano with diagnostic
software to chase outboard problems. Inboard problems with the Nano are
probably not fixable (how does the nano tell if an on-board pull-up
resistor is bad vs the outside world causing what it sees?).

Out of the ten Nano's I've ordered I found one that did not work
right. It simply went in the trash can. Not worth trying to figure out
why when the next one worked ok. Substitution is a valid
troubleshooting tool.

tim ab0wr



On Sat, 28 Apr 2018 11:53:53 -0600
"Arv Evans" <arvid.evans@...> wrote:

Lawrence

I think the suggestion was to use a working Arduino board to help do
diagnostics on
an attached BITX transceiver. This would be different from expecting
a non-working
processor to diagnose itself. Question in this is whether the
Arduino/Raduino would
have built-in code for BITX diagnostics, or would it require a code
reload for the
Arduino to do this task.

While smaller mini-frame systems VAX, DEC, etc. used to have a single
processor
my experience with large mainframes (IBM-360, Bell Labs 4ESS, etc.)
had multiple
core processors and actually could, in some cases, do diagnostics on
limited parts
of the system. But this is way beyond what we are dealing with in
the BITX world
where a rather simple AVR Mega-328 micro-controller is all we have to
work with.

There have been earlier comments regarding Arduino based test
equipment that could
be designed and built such that it would be an accessory or separate
controller used
for diagnostic purposes, but this is more stand-alone test sets than
an internal
diagnostic element.

Arv K7HKL
_._


On Sat, Apr 28, 2018 at 11:26 AM, Lawrence Macionski via Groups.Io <
am_fm_radio@...> wrote:

40 years as a senior field engineer on big main frames and such..
Self diagnostic hardware and software is wonderful provided the
machine is actually working when you run the diagnostics. most
engineers who rely on diagnostics puke when they can't run them for
various reasons.

I have a few thousand airline miles "fixing" for instance a VAX
11/785 mainframe down for 3 days.. Can't boot, can't run
diagnostics. The 11/ 785 CPU was 29 24x24 inch boards, all were
changed. Even changed the microvax computer -boot loader. (a 8-12
board mini-computer w/ 8"floppy that loaded the mainframe
microcode). My Solution/findings: Every 8" floppy on site was bad,
the ones I brought worked just fine. Perhaps a disgruntled employee
demagnetized all floppies but the one that was loaded in the
loader. then it eventually went bad..(The perfect crime)

Drove all night- Detroit to Indianapolis once for a 1amp 5 volt
fuse..System down 3-4 days. (SUN Microsystems 3/xxx series
computers, had the 5 volt line to the optical mouse fused.) in
order to log in you had to move the mouse to the login window even
to log in as root. The local engineer even changed the MOBO- and
the new MOBO had no fuse in the fuse holder.. National Tech support
told him to keep checking the configuration berg jumpers never even
knew there was a fuse on the board.. The old MOBO had a blown
fuse.. BTW- Sun Microsystems never had a part number for that fuse
or even mentioned it in engineering documentation.. a 3rd MOBO
arrived by air courier as I was leaving. It did have a new good
fuse


If you've read this far. I have to ask this question:
uBITX are not $3000 radio's.. DXpeditions don't depend on 1 radio
but pack extra's. For the $120-180 we have invested in a working
rig, Isn't it realistic to invest in a second? I have multiple
rigs as perhaps I'm blessed. but there are times (close lightening
strike) that can render a uBITX or anyother rig perhaps unfixable.
Still they are fun aren't they?

I'm having problems uploading to my Nano since I did upload a hex file successfully. I cannot get even the blink example to load now. NADA. But the hex (avrdude) loader still will upload hex files. It must have busted the bootloader or something.

Arv,

I have a spectrum analyzer. I use a two-tone generator. There is no
issue with spurious microphone response. While the two-tone gen is
just a standard kit, I can't see any distortion on my oscilloscope in
either the time domain or in the frequency domain using the scopes
FFT math function. I'm sure there is some but not enough to cause
this carrier suppression figure. Nor are there any ultra-sonic tones
showing up on the spectrum scan, either at audio freq's or rf freqs.

Just a single tone from the two-tone generator and the carrier.

25db is the *best* I can get by adjusting the BFO. Standard adjustment
of the BFO gave about 18db to 22db. Moving the BFO down the filter
skirt gave me another 3db.

tim ab0wr

On Sat, 28 Apr 2018 11:13:53 -0600
"Arv Evans" <arvid.evans@...> wrote:

Tim AB0WR

Some earlier BITX transceivers did use a ring mixer but the carrier
suppression was
not noticeably better than with the present design. Allison's
comments are valid and
reflect a good place to start looking.

Placing the BFO down the edge of the crystal filter passband helps
improve carrier
rejection and improves audio by filtering off unneeded lower frequency
voice products.
You can tailor the lower frequency speech response by how far down the
filter skirt
you place the BFO.

If you have means to do spectrum analysis you can measure crystal
filter response
and use that information to determine where the BFO should be set.
If you do not
have spectrum analysis tools, it is still possible to do a manual
sweep by adjusting the
BFO in small (20 to 100 Hz) steps across the filter passband and plot
the filter output
using a diode detector and graph paper. Note that linear graph paper
will show an
expanded curve where log graph paper will show a more conventional
decibel curve.

If noise is being injected into the balanced modulator via the
microphone or microphone
amplifier it will not be possible to get a deep null in carrier
balance. It is conventional
practice to short the microphone input while doing carrier balance
adjustments and
measurement.

Allison's comment regarding possibility of undetected ultra-sonic
tones present that
can cause unwanted carrier insertion is something that we do not
usually look for.
A quick look at modulator AF input with an oscilloscope would
probably show any
such problem.

Typical crystal ladder filters usually show a steeper curve on its
lower sideband than
on the upper sideband. Some of the high-IF designs ignore that and
as a result will
show less carrier rejection on either USB or LSB, depending on the
design.







<goog_592175929>



Arv K7HKL
_._



On Fri, Apr 27, 2018 at 8:50 PM, Tim Gorman <tgorman2@...> wrote:

I've never been able to get over 25db of carrier rejection
according to my Rigol DSA815. Not unless I move the BFO so far that
signals are unintelligible. If you adjust by 6db to allow for PEP
equivalence this is still only 31db of rejection.

In looking at the modulator circuit I don't see much of a way to
increase carrier rejection without major butchery, i.e. totally
replacing the modulator with a ring mixer which would allow
providing for a carrier balance adjustment.

tim ab0wr

On Fri, 27 Apr 2018 18:22:21 -0700
"ajparent1/KB1GMX" <kb1gmx@...> wrote:

Two things result in carrier...

One is the BFO too close to or in the filter passband, it should
be 6-10 db down the edge of the filter. Blaming the filter will
not fix that, unless its seriously broken. NOTE: Each unit
will vary some on the best BFO setting this happens with
commercial filters too.

The other is imbalance in the modulator circuit. Solution is fix
it.

There is a remote possibility of a tone at higher than you can
here present in the tx due to a circuit or wiring issue.

Its not rocket science to measure the power out and the residual
carrier. a 50 ohm load, a diode detector is all that is needed
plus a voltmeter. Compare power out at full power and with no
audio at all the ratio in DB should be better than 40DB
(10,000:1) or for 10W out less than 1mW.

Allison