Re: Pulling Arduino data apart

Dr Fred Hambrecht

Anytime knowledge is imparted it cannot be viewed as “wasted bandwidth”. I for one enjoyed the conversation.

v/r

Fred W4JLE

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Thursday, March 8, 2018 17:15
To: BITX20@groups.io
Subject: Re: [BITX20] Pulling Arduino data apart

Agreed, we've wasted too much time on something not at the top of our priorities here.
Anyone wishing to continue this discussion is welcome to send me a private message.

In parting, I believe that once the data is in the CPU, in this case stored as a 32 bit integer
in a register, endian-ness is not a factor.  This code looks correct to me:

Here's C code for machine A to send a 32 bit integer as a sequence of four bytes in little endian order::
sendbyte(data32);  sendbyte(data32>>8);  sendbyte(data32>>16);  sendbyte(data32>>24);
And code for machine B to receive that 32 bit integer (assumes getbyte() returnes an unsigned 8 bit integer):
data32=getbyte();  data32|=getbyte()<<8;  data32|=getbyte()<<16; data32|=getbyte<<24;
This C code doesn't care if the machine it is on is big endian or little endian.

An as I understand it, Jack disagrees, here's his argument:

the byte order, otherwise why are you interested only in the high byte. Your code:

sendbyte((data32>>24)&0xff);

to send a byte works great if the data is big endian:

01010101 00000000 00000000 00000000.         // Yellow is the byte of interest

However, if you don't know the byte order and it is:

00000000 00000000 00000000 01010101

Your code would throw the relevant data on the floor. Your code is only safe if you know
the order. A union is a simple way to determine that order.

Jerry, KE7ER

On Thu, Mar 8, 2018 at 12:53 pm, Jack Purdum wrote:

We've wasted enough bandwidth on this. I think unions are a great way to learn how data are organized for a given compiler and are well-worth knowing about. Anyone who doesn't think so can easily ignore them.

Re: uBITX Firmware CEC Version Added WSPR function, I am looking for a beta tester.

Philip

Carlos.
Just enter it in the box, it is in hz. Not Mhz, so no decimal point.
Philip.

Re: uBITX Firmware CEC Version Added WSPR function, I am looking for a beta tester.

Carlos E. Wenzel <Ik2yra@...>

So simple.... TKS Philip
Carlos

2018-03-09 21:01 GMT+01:00 Philip :

Carlos.
Just enter it in the box, it is in hz. Not Mhz, so no decimal point.
Philip.

--
Carlos Wenzel
ik2yra@...
+39-3284684518
Skype: IK2YRA

Re: uBITX Firmware CEC Version Added WSPR function, I am looking for a beta tester.

Carlos E. Wenzel <Ik2yra@...>

uBiTx on air....Tks Ian / Philip

Carlos

2018-03-09 21:12 GMT+01:00 Carlos E. Wenzel :

So simple.... TKS Philip
Carlos

2018-03-09 21:01 GMT+01:00 Philip :
Carlos.
Just enter it in the box, it is in hz. Not Mhz, so no decimal point.
Philip.

--
Carlos Wenzel
ik2yra@...
+39-3284684518
Skype: IK2YRA

--
Carlos Wenzel
ik2yra@...
+39-3284684518
Skype: IK2YRA

Re: RD16HHF1 power curve flattening...some

Nick VK4PP

Mods so far, in tested.

Re: tx pop

John Pieper

I found a much better place to connect the drain of the MOSFET. First I replaced R70 with a 510 ohm resistor that I happened to have in the same footprint.

Then I connected the MOSFET drain to the relay side of that resistor, i.e. to the point M2 on the schematic. This setup still shorts the incoming audio to ground and kills the pops, but leaves a voltage divider of R253 and R70 connecting the sidetone to the volume control. Depending on your value of R253, this may be perfect as is. My R253 was 220 k and I needed more volume, so I put a 50 k trimpot across R253. It is just about right for me at maximum resistance, but I can adjust it downward if I should want more volume still. If your R253 is a smaller value and the sidetone is too loud, just replace it with something of higher resistance.

The volume control will now have final control over the level and can be tweaked in operation if needed.

73,

Re: Pulling Arduino data apart

Jerry Gaffke

Here's a starting point on web resources regarding this big/little endian stuff in case you're curious.
https://stackoverflow.com/questions/13994674/how-to-write-endian-agnostic-c-c-code

But for most of us this is a non-issue, and you needn't worry about it.
And you certainly don't have to suffer anybody arguing about it.

Code on the Nano (and likely in most any Arduino environment) is little endian.
Though on an 8 bit machine like the Nano, endian-ness is mostly a matter of what the compiler wants to do.
https://www.avrfreaks.net/forum/endian-issue
https://www.avrfreaks.net/forum/big-endian-or-little-endian-0

Jerry, KE7ER

On Fri, Mar 9, 2018 at 11:46 am, Dr Fred Hambrecht wrote:

Anytime knowledge is imparted it cannot be viewed as “wasted bandwidth”. I for one enjoyed the conversation.

ubitx LCD display

Richard E Neese

whats the latest on the new w8tee lcd vfo for the ubitx ?

Re: uBITX Mic Wireup

Tim Gorman

Jerry,

Having a live mic with a separate, unassociated PTT switch can lead to
inadvertent transmissions if the PTT gets operated accidentally. If the
mic is not live all the time then all you transmit on an accidental PTT
operation is a suppressed carrier which hopefully won't bother anyone.

It doesn't happen a lot but it *does* happen. Someone accidentally
pushes his foot switch with a live mic and sends out a discussion with
the wife (spouse) over the air.

Admittedly you can butt transmit with a PTT CB mic or 2-meter ham mic
if you sit on it. It happens also.

For me, the switch is there in the mic and I don't see any reason not
to use it. If you tear a lot of communication mics apart you will see
that the mic element is wired through the PTT switch on most of them.
Apparently someone thinks its a good idea!

tim ab0wr

On Fri, 09 Mar 2018 07:54:26 -0800
"Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:

On Fri, Mar 9, 2018 at 07:23 am, Tim Gorman wrote:

The mic is only actually connected when the PTT switch is
pushed. ....   This is why I recommend using a communications mike
instead of a standalone mic with a separate PTT switch.

Re: Variable power control

Tim Gorman

Walter,

What voltage are you feeding this with? I assume it is more than
24v in order for you to have a 24v position.

If you are running in the 10 volt position, for instance, that would be
drop of at least 24v - 10v = 14v. Fourteen volts at .5amp is 7W being
dropped into that transistor. That's a pretty fair amount of heat.

tim ab0wr

On Fri, 09 Mar 2018 06:17:16 -0800
"Walter" <@whuyckjr> wrote:

On Wed, Feb 21, 2018 at 06:23 pm, LKNDAVE wrote:

i did the hokie pokie and this jpg came out

Based on this design I built this attached circuit.

It controls voltage nicely.  Really helps limit output power while
working digital.

However the TIP 142 really generates some heat.  I have a heat sink
on it but it will need to be much larger.  it is only drawing
about .5 amp (1/2 amp) while transmitting.

Does that seem normal?  it the heat something I should be concerned
about?  Or just provide a better heat sink and run it?

Thanks for the circuit idea and plan.

--
73, W9KJO
Walter

Re: uBITX Firmware CEC Version Added WSPR function, I am looking for a beta tester.

Philip

Thanks Ian. For a great updated to include WSPR, It was a surprise.

Philip G7JUR.

Re: tx pop

PeteWK8S

Thank John, moving the Drain to R70 (changed to 510) helped restore my volume. However, I am getting the pop going key down RX to TX but no pop going from TX to RX.
So the MOSFET is not muting quite fast enough.

How did you determine the value you used for R70?

Pete WK8S

Re: uBITX Mic Wireup

Shaun

" If you tear a lot of communication mics apart you will see that the mic element is wired through the PTT switch on most of them."

That is exactly what I would expect and have seen in the past, but again, the mic wire up I saw on an earlier post for an older version did have the PTT as a separate circuit, not wired serially with the electret. While it doesn't address the mic wire up specifically, the wiring diagram for the uBITX from the website seems to suggest the same, PTT and mic are two separate circuits. I think you have confirmed my original way of thinking of how I should wire it up, i.e. closure of the PTT switch applying ground to the MIC- side of the electret, and is the way I will go.  I am using an old HT spkr\mic and going that route just means I need to move one connection point internally and I'm where I need to be. Thank you for the assist, Tim

Shaun
KEØNLN

On Fri, Mar 9, 2018 at 3:14 PM, Tim Gorman wrote:
Jerry,

Having a live mic with a separate, unassociated PTT switch can lead to
inadvertent transmissions if the PTT gets operated accidentally. If the
mic is not live all the time then all you transmit on an accidental PTT
operation is a suppressed carrier which hopefully won't bother anyone.

It doesn't happen a lot but it *does* happen. Someone accidentally
pushes his foot switch with a live mic and sends out a discussion with
the wife (spouse) over the air.

Admittedly you can butt transmit with a PTT CB mic or 2-meter ham mic
if you sit on it. It happens also.

For me, the switch is there in the mic and I don't see any reason not
to use it. If you tear a lot of communication mics apart you will see
that the mic element is wired through the PTT switch on most of them.
Apparently someone thinks its a good idea!

tim ab0wr

On Fri, 09 Mar 2018 07:54:26 -0800
"Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:

> How is this an advantage?
>
> On Fri, Mar 9, 2018 at 07:23 am, Tim Gorman wrote:
>
> >
> > The mic is only actually connected when the PTT switch is
> > pushed. ....   This is why I recommend using a communications mike
> > instead of a standalone mic with a separate PTT switch.

Re: tx pop

John Pieper

Pete,

Maybe some more experimentation with the capacitor value is needed. The diode has some finite forward resistance so it will take some small amount of time for the cap to charge up. I originally had the circuit connected to U1 input as well and had settled by experiment on 330 nF. Didn't see any change in effectiveness when I moved it to M2. So maybe a somewhat smaller capacitor will fix it. (Don't remember what I have for the resistor, btw). Also by the way, my gate circuit is slightly different. I have only the diode in series with the T/R signal going to the gate. Both the capacitor and resistor are connected from the gate to ground. I seem to remember that I had a hard time getting it to work until I tried it this way. Don't know what difference it might make, though.

For R70, I knew I wanted something larger than 10 ohms to have the voltage divider produce enough output, but not so large that the maximum volume available from the volume pot would be reduced significantly. I saw that I had the 510 ohm part and thought, "try this". Simple as that.

73, John

Re: RD16HHF1 power curve flattening...some

K9HZ <bill@...>

Nice… any power to it yet?

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

Moderator – North American QRO Yahoo Group.

email:  bill@...

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Nik VK4PLN
Sent: Friday, March 9, 2018 2:35 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

Mods so far, in tested.

 Virus-free. www.avg.com

shipping update

John KG9DK

ordered January 8, 2018
notice of being shipped March 6, 2018

john kg9dk

Re: The issues of the TDA2822

w7hd.rh <w7hd.rh@...>

This is the modification I came up with to implement a 7805 to supply the TDA2822.

Please check it over for errors.  One trace cut and scrape a little off the board and solder in the 7805.

Ron W7HD

On 03/09/2018 06:41 AM, Raj vu2zap wrote:
Skip,

For me obsessed in experimenting with receivers, the audio parts graduated from LM380 then smaller 386 and then someone
mentioned the TDA2822.. I always had a soft corner for National Semi but switched to TDA. I always worked on 12V and
the TDA in bridge mode. Compared to 386 the 2822 sounded warm and nice lows with 2W out.

Vaguely I remember blowing one to reverse polarity supply. One TDA melted my solderless bread board but survived. I now realise
that it IS designed for 9V or lower although it can take 15V max.

Raj

At 09-03-18, you wrote:
Raj, when you use the TDA 2822 in other designs what voltage are you running them at? Is it at the 9 volt dc via a voltage regulator?

Skip Davis, NC9O
--
W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320

Re: The issues of the TDA2822

K9HZ <bill@...>

Works...

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

Moderator – North American QRO Yahoo Group.

email: @Doc_Bill

-----Original Message-----
From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of w7hd.rh
Sent: Friday, March 9, 2018 7:33 PM
To: BITX20@groups.io
Subject: Re: [BITX20] The issues of the TDA2822

This is the modification I came up with to implement a 7805 to supply the TDA2822.

Please check it over for errors. One trace cut and scrape a little off the board and solder in the 7805.

Ron W7HD

On 03/09/2018 06:41 AM, Raj vu2zap wrote:
Skip,

For me obsessed in experimenting with receivers, the audio parts
graduated from LM380 then smaller 386 and then someone mentioned the
TDA2822.. I always had a soft corner for National Semi but switched to TDA. I always worked on 12V and the TDA in bridge mode. Compared to 386 the 2822 sounded warm and nice lows with 2W out.

Vaguely I remember blowing one to reverse polarity supply. One TDA
melted my solderless bread board but survived. I now realise that it IS designed for 9V or lower although it can take 15V max.

Raj

At 09-03-18, you wrote:
Raj, when you use the TDA 2822 in other designs what voltage are you running them at? Is it at the 9 volt dc via a voltage regulator?

Skip Davis, NC9O

--
W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320

---
This email has been checked for viruses by AVG.
http://www.avg.com

Re: uBITX Mic Wireup

Tim Gorman

Shaun,

The ubitx doesn't have a balanced mic input, i.e. mic leads that don't
have one connected directly to system ground. In a balanced feed the
shield wire would be the system ground and would act as a shield to both
mic wires. Ideally in such a case the PTT would probably also have two
leads, a plus and minus, although many times the shield is just used as

The PTT shouldn't be wired serially with the mic, both just use a
common ground. When the PTT is pushed the PTT switch closes the PTT
lead to the shield, i.e. system ground. At the same time the mic lead
from the element is connected to the mic lead in the cable. The minus
mic lead is connected solidly to the shield, i.e. system ground.

If the ubitx ran more power it might be necessary to take more care
with the mic circuitry. At 10-15 watts it just isn't necessary as long
as the wires inside the cabinet are dressed properly and kept away from
the PA section of the circuit board.

Yaesu site and look at the page with the connector wiring, you'll see
on the microphone connector that there are two mic leads that are
separate from system shield. In fact there is even a totally separate 5v
lead for powering an electret element. Yaesu expects there to be a
blocking capacitor on the mic lead to isolate the 5v from the radio mic
circuit.

tim ab0wr

On Fri, 9 Mar 2018 18:04:27 -0600
"Shaun" <slong682000@...> wrote:

" If you tear a lot of communication mics apart you will see that the
mic element is wired through the PTT switch on most of them."

That is exactly what I would expect and have seen in the past, but
again, the mic wire up I saw on an earlier post for an older version
did have the PTT as a separate circuit, not wired serially with the
electret. While it doesn't address the mic wire up specifically, the
wiring diagram for the uBITX from the website seems to suggest the
same, PTT and mic are two separate circuits. I think you have
confirmed my original way of thinking of how I should wire it up,
i.e. closure of the PTT switch applying ground to the MIC- side of
the electret, and is the way I will go. I am using an old HT
spkr\mic and going that route just means I need to move one
connection point internally and I'm where I need to be. Thank you for
the assist, Tim

Shaun
KEØNLN

On Fri, Mar 9, 2018 at 3:14 PM, Tim Gorman <tgorman2@...> wrote:

Jerry,

Having a live mic with a separate, unassociated PTT switch can lead
to inadvertent transmissions if the PTT gets operated accidentally.
If the mic is not live all the time then all you transmit on an
accidental PTT operation is a suppressed carrier which hopefully
won't bother anyone.

It doesn't happen a lot but it *does* happen. Someone accidentally
pushes his foot switch with a live mic and sends out a discussion
with the wife (spouse) over the air.

Admittedly you can butt transmit with a PTT CB mic or 2-meter ham
mic if you sit on it. It happens also.

For me, the switch is there in the mic and I don't see any reason
not to use it. If you tear a lot of communication mics apart you
will see that the mic element is wired through the PTT switch on
most of them. Apparently someone thinks its a good idea!

tim ab0wr

On Fri, 09 Mar 2018 07:54:26 -0800
"Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:

On Fri, Mar 9, 2018 at 07:23 am, Tim Gorman wrote:

The mic is only actually connected when the PTT switch is
pushed. .... This is why I recommend using a communications
mike instead of a standalone mic with a separate PTT switch.

Re: Variable power control

John Backo

Good thought, Marco.

But most. if not all variable VR's have a fixed or lesser
VA output. IF you lower the voltage, usually the available
amperage goes down as well...

I use two in my bench supply, one with a 7815 and one
with a LM338. They work well to provide a variable voltae
but the available current is not 5A (say) for the LM338
unless the voltage is quite high. At very low voltages,
the available current is 0.5A or less.

But it is a good thought. Possibly it could be rigged
as a linear supply with 2 LM338's and a LM324 regulator...

It would be cheaper than buying separate fixed supplies.
Also cheap are variable shunt and digital supplies, but
they usually have a big RF noise problem and require
some hefty filtering..

john