Date   

Re: SWR

Tim Gorman
 

No twist. We are saying the same thing. Just different ways.

The only difference is that I'm saying swr is a waste of time to try
and calculate. Even in a dual-pointer swr meter you are really looking
to minimize the reverse power indicator with a tuner, not maximize
forward power.

In fact, in some cases maximum forward power and minimum reverse power
don't occur at the same matching point. So what do you do? You minimize
reverse power. So what does forward power and swr buy you?

tim ab0wr

On Mon, 7 May 2018 13:48:46 -0500
"K9HZ" <@Doc_Bill> wrote:

I think you twisted my words. I said:

1. If you are resolving variables that are not time dependent between
each other (like radio current and s-meter reading), you can let the
on board A/D free run and grab and use what ever is in the register
for that variable at any time. Yes they are all muxed but that
doesn't matter because all you want is “a number”.

2. You cannot do time dependent resolution of different variables on
the Arduino if timing is critical/ the variables are time dependent.
Otherwise its like saying ill take the forward power today and the
reverse power tomorrow and calculate swr from non-time related data.
You are right, the A/D pins are muxed and that just exacerbates the
problem as the number of analog pins used grows.

3. If you do have variables where the time relationships are
critical (swr, some audio sampling, filters, etc.) then the pest
place to do the conversion is off the arduino. Use a sample and hold
A/D for critical timed variables so the data time stamps match. It
may or may not be critical how long it takes the data to get off the
board to inside the Arduino. For for/rev power for swr it doesnt
matter as long as the data pair has the same resolved time stamp.
Audio and filters (fft) is more problematic. The answer is correct
but shifted in real time so what you usually see (hear) is the right
sound but delayed.

It appears the temporal issue with sampling causes may people
problems.



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

email: @Doc_Bill


On May 7, 2018, at 12:14 PM, Tim Gorman <tgorman2@...> wrote:

Since the ADC on the nano is muxed, i.e. not every channel has its
own ADC, it takes time for the ADC to be connected to a specific
channel and for that channel to settle to a correct reading. So you
do lose time slots while this is occuring. It's why a random read
takes 2 to 3 times longer than successive reads from the same
channel.

At least that's how I read the specs.

And you are right about letting the ADC in the peripheral just run
continuously. I don't consider SWR to be a critical item. You can
measure reverse power when you need to. And you can do the same for
forward power if you want. SWR isn't going to tell you anything
extra over just the two measurements themselves.

tim ab0wr

On Mon, 7 May 2018 11:40:02 -0500
"K9HZ" <@Doc_Bill> wrote:

Correct, but it is more important that, in the case of SWR that the
forward power and the reverse power be synced in time. Thats where
the Arduino fails and you would want to do it off the Arduino.
With ten random variables that don't need to be time related, you
can just let the A/D run continuously and just grab data from the
conversion register when you need it. They run in parallel with
instruction processing so no time slots are lost.


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

email: @Doc_Bill



High Resolution Board Photos #ubitx

atouk
 

Is there a high resolution copy of the uBITX silkscreen or a good pic of the board (unpopulated) available?

Us old farts need some help finding those tiny parts. 
It would also be handy for scribbling some notes and documentation on what mods/changes we've done to it for future reference, or if the kit gets handed down.


Re: SWR

Jerry Gaffke
 

I don't think you need differential ADC to read a diode detector with forward bias.
I was going to wire up Diz's TandemMatch as described in post 47634
then take a reading just before the transmitter is keyed, save that as the base reading,
Subtract that base reading from anything read after the transmitter is turned on.

Using Paul's 1.1v internal reference would definitely help out at low power levels.

Jerry, KE7ER


Re: SWR

Arv Evans
 

Paul  AA9GG

My interest and direction is in making a very low signal level SWR or impedance bridge
for measuring things like the input and output impedance of various filter circuits.  I already
built a Bourne-bridge type SWR meter for an earlier BITX17A transceiver.  It works great!

Many hams could probably make use of the precision and reliability of ARDUINO based
test equipment.  Cost for such instruments is quite low and the satisfaction "I built it myself"
is high.  There are many on-line examples, or there is the opportunity for individuals to
expand their knowledge by doing the research and designing their own test equipment.
Start with a simple Arduino based DC voltmeter and modify it to do many more functions.

This is FUN!

Arv  K7HKL
_._


On Mon, May 7, 2018 at 3:41 PM, AA9GG <paul.aa9gg@...> wrote:
The on-board A/D has 10-bit resolution (0-1024).  If you use a precision 5V external ref, that comes out to be 0.0048828125 volts per bit.  If you use the internal 1.1v ref, it works out to be 0.00107421875 volts/bit.  I would think that would be more than enough for an SWR meter.  You could also try running an average in a "ring array", grabbing and storing values only when the transmitter is keyed.  I just built the ND6T SWR/PWR ckt into my BitX40 I have the outputs all scaled and tied it to ADC6 and ADC7, using the internal 1.1v ref. I haven't coded it yet, but I foresee no issues.

On Mon, May 7, 2018 at 4:18 PM, Kees T <windy10605@...> wrote:
Great input Arv, thanks......always good to hear real data.

So maybe no differential input MCP3422 is required with an unbiased HSMS-2815.....but if you want to go below the diode Vf, it is.

73 Kees K5BCQ 




--
Paul Mateer, AA9GG
Elan Engineering Corp.
www.elanengr.com
NAQCC 3123, SKCC 4628



Re: SWR

Arv Evans
 

Kees K5BCQ

My impromptu tests were just to verify how to use the Arduino NANO built-in ADC.

I do agree that diode detectors using forward-biasing are an interesting area to explore. 
Possibly some sort of differential measurement of a diode bridge might get sensitivity
to almost equal that of popular integrated circuit detectors, but without the log curve
capability.  More thought and more testing is probably warranted there.

Arv K7HKL
_._


On Mon, May 7, 2018 at 3:18 PM, Kees T <windy10605@...> wrote:
Great input Arv, thanks......always good to hear real data.

So maybe no differential input MCP3422 is required with an unbiased HSMS-2815.....but if you want to go below the diode Vf, it is.

73 Kees K5BCQ 



Re: kd8cec code mod

AA9GG
 

On Mon, May 7, 2018 at 3:01 PM, Richard E Neese <kb3vgw@...> wrote:
if anyone knows how to reach kd8cec I would like to request a mod in his code to add in cw decode function.




--
Paul Mateer, AA9GG
Elan Engineering Corp.
www.elanengr.com
NAQCC 3123, SKCC 4628


Re: SWR

AA9GG
 

The on-board A/D has 10-bit resolution (0-1024).  If you use a precision 5V external ref, that comes out to be 0.0048828125 volts per bit.  If you use the internal 1.1v ref, it works out to be 0.00107421875 volts/bit.  I would think that would be more than enough for an SWR meter.  You could also try running an average in a "ring array", grabbing and storing values only when the transmitter is keyed.  I just built the ND6T SWR/PWR ckt into my BitX40 I have the outputs all scaled and tied it to ADC6 and ADC7, using the internal 1.1v ref. I haven't coded it yet, but I foresee no issues.

On Mon, May 7, 2018 at 4:18 PM, Kees T <windy10605@...> wrote:
Great input Arv, thanks......always good to hear real data.

So maybe no differential input MCP3422 is required with an unbiased HSMS-2815.....but if you want to go below the diode Vf, it is.

73 Kees K5BCQ 




--
Paul Mateer, AA9GG
Elan Engineering Corp.
www.elanengr.com
NAQCC 3123, SKCC 4628


Re: boosting the power on 28 MHz #ubitx

Kees T
 

Allison,

Class C is fine for CW but many of these guys want SSB and I personally like some of the Digital Modes (with the carrier on).

73 Kees K5BCQ


Re: boosting the power on 28 MHz #ubitx

Kees T
 

allison,

That's what I use on my 20W Amp.....copper tubing covered with 2 #61 material Ferrite sleeves and a copper plate connecting the tubes, works well and does not run hot. Large heatsink required for the RF Mosfets.

73 Kees K5BCQ


Re: SWR

Kees T
 

Great input Arv, thanks......always good to hear real data.

So maybe no differential input MCP3422 is required with an unbiased HSMS-2815.....but if you want to go below the diode Vf, it is.

73 Kees K5BCQ 


Re: boosting the power on 28 MHz #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

Less than 1% at 5% your likely starting to compress and getting nasty.  The target for
what some would call passable IMD and linearity of more than  -20Dbc (1%) and
better is -30dbc (about .1%).  

But it all that depends on if your doing SSB voice or some more critical modulation (data).

All that said for the amp in question for 2M input to output gain of 9.8DB was nearly flat (less
than a db) to 90W where it starts to deviate. The onset of 1db compression so 95W was
where it was dialed up to light red.  Both input and output sensors were simple
directional couplers.  Lot of runs putting power in and watching power out with nominal
DC and  low DC.  Low DC causes it to hit the wall at 85W.  Its importance is the radio
(TenTec 6n2) can run up to 20W and at most 8-9w of drive is needed so it serves more
to warn me I moved the knob.   The 6M amp used has a simpler deal, warn if the input
power is more than 8W (8W in 160 out).  For the station its meaningful as power is
solar (about 400W) charged battery (10 cells of large industrial flooded NiCd 150AH).
Since they are batteries monitoring charge and voltage is a good thing to do lest the
radios and amps get weird from under voltage.  LIfe as it exists running the station
off grid.  FYI no requirement to do solar power save for its a hobby.


Allison


Re: SWR

Kees T
 

As I mentioned earlier, the reason I selected the HSMS-2815 matched diodes was that the forward voltage drop was 150mV to 200mV at 10nA. They were forward biased with a AAA cell and I would use a coin cell today. Maybe also use the MCP3422 as I did before which has I2C.

73 Kees K5BCQ


Re: Coding styles

Jack, W8TEE
 

Allison:

Actually, the 64x16 was a hacked Hitachi TV set that I was using at the time! I couldn't afford a real terminal.

Truth be told, some elements of C++ are just begging for trouble (e.g., multiple inheritance). I was in SF at the Software Development Conference when Bjarne gave his keynote talk on "C with Classes". There were 750 people there for the talk. Ninety minutes later, 749 of us walk out saying: "What the **** was that?!"

C is powerful enough to let you shoot yourself in the foot, but C++ will let you blow your whole leg off. I love the benefits of OOP, but you can get a large measure of those benefits without having to fully implement C++. It just takes a little thought before you start banging on the keyboard.

Jack, W8TEE


On Monday, May 7, 2018, 2:08:32 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


As a bleeding edger...  CP/M 1.3, 1.4 and 2.2,  Smallc,  BDS C and even Pascal.
My copy of K&E has a Bell system cover and marginal notes from K!  I Used to call
on them back when and it was a gift, one I treasure.   However space was never
an issue as I was running hard disks before many.  I may add that system is
still in use as I can bang out good code fast on it (large library and old code
reserve) and a 10mhz Z80 kind does the job.

When I want to show the kiddies I fire up the the microPDP 11/23 (its smaller)
and run Unix V6 and show how far we have not gone.

Coding style.  I try to keep the code English as adverse to "reads like Greek".
Many many years in assembler and macro assemble if I could not figure it
out six months later either it needed more comments or I was trying to be
too slick.  So all the C I wrote/write is every effort to be plain, structured
and consistent in style even if I'm doing different than last project.  One
area is data structures shat I see these days is very hard to decrypt due
to layers of layers.  Yes, I know its C++, sometimes leaving out the ++ part
makes it cleaner other times It is handy to make it better packaged.  I'm
used to writing for small systems as in embedded and often resource limited.
Arduino feels big to me!

Oh, 64x16 must be a PT VDM-1 video or similar, Stiill have a system using that.
I've accumulated systems over the years astating with my first build back in '74.

Allison


Re: SWR

Arv Evans
 

Bill, and others.....

Trying to follow the conversation but it seems that we may be splitting hairs in use of
the built-in ADC and ADC Multiplexing.  Since CW RF is usually used for SWR and
for RF voltage measurements, would there be any appreciable change in readings
of two different ADC inputs during the few milliseconds required to take two successive
I do understand that if we are attempting to measure phase shift there could be
differences due to measurement delay, but for normal ham radio use we are just using
the Arduino NANO as a DC voltmeter.  The measurements can be averaged over
several sample-and-hold cycles, or use two successive samples with the same ADC
input to insure the charge capacitor is fully charged and throw away the first sample. 

Of course this is measuring with a CW carrier, not with modulation or a two-tone
scheme.

I just now set up a NANO to measure DC voltage on two different ADC inputs.  There
is a small difference between first sample and successive ones in a string of samples
but after the first sample the voltage is stable.  Measuring 1 volt versus measuring 4
volts shows the same first-sample offset and stable readings for successive samples
of the same input.

Measuring two different inputs on separate ADC ports also shows the first-sample
offset with that being a -0.005 volt constant error if sampling alternate input ports
that have different voltages on them.  When I did 4 sequential samples of one port
and then the same on the other port, the 1st sample on each port shows the small
negative error but the 3 subsequent samples show the same 3.000 reading.

From this it seems that the 1st sample could be disregarded and a second sample
used for minimum error on same-port measurements. 

Next I configured my test equipment with a diode rectifier, 0.1 mfd filter cap, and
10K load resistor on the output of an Si5351a synthesizer at 7.0 MHz.  Output
attenuator was set for a constant sampling reading of 3.000 volts on the NANO. 
First sample measurements alternating between 4 samples the RF detector and
4 samples of another input at ground level shows the first RF sample may or may
not be exactly the same as the 3 successive samples (it jitters back an forth between
3.000 volts and 2.995 volts).  The grounded input always shows 0.000 volts for all
4 samples.

From this experiment I would feel confident that continuous CW output into an
SWR bridge would show adequate voltage measurements for single shot samples
and would be super accurate if two subsequent samples were taken on each ADC
input with the first sample dropped and the second sample used.

Arv  K7HKL
_._
 



On Mon, May 7, 2018 at 12:48 PM, K9HZ <bill@...> wrote:
I think you twisted my words.   I said:

1. If you are resolving variables that are not time dependent between each other (like radio current and s-meter reading), you can let the on board A/D free run and grab and use what ever is in the register for that variable at any time.  Yes they are all muxed but that doesn't matter because all you want is “a number”.

2. You cannot do time dependent resolution of different variables on the Arduino if timing is critical/ the variables are time dependent.  Otherwise its like saying ill take the forward power today and the reverse power tomorrow and calculate swr from non-time related data. You are right, the A/D pins are muxed and that just exacerbates the problem as the number of analog pins used grows. 

3.  If you do have variables where the time relationships are critical (swr, some audio sampling, filters, etc.) then the pest place to do the conversion is off the arduino. Use a sample and hold A/D for critical timed variables so the data time stamps match. It may or may not be critical how long it takes the data to get off the board to inside the Arduino.  For for/rev power for swr it doesnt matter as long as the data pair has the same resolved time stamp. Audio and filters (fft) is more problematic.  The answer is correct but shifted in real time so what you usually see (hear) is the right sound but delayed. 

It appears the temporal issue with sampling causes may people problems. 



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


email:  bill@...

 


On May 7, 2018, at 12:14 PM, Tim Gorman <tgorman2@...> wrote:

Since the ADC on the nano is muxed, i.e. not every channel has its own
ADC, it takes time for the ADC to be connected to a specific channel
and for that channel to settle to a correct reading. So you do lose
time slots while this is occuring. It's why a random read takes 2 to 3
times longer than successive reads from the same channel.

At least that's how I read the specs.

And you are right about letting the ADC in the peripheral just run
continuously. I don't consider SWR to be a critical item. You can
measure reverse power when you need to. And you can do the same for
forward power if you want. SWR isn't going to tell you anything extra
over just the two measurements themselves.

tim ab0wr

On Mon, 7 May 2018 11:40:02 -0500
"K9HZ" <bill@...> wrote:

Correct, but it is more important that, in the case of SWR that the
forward power and the reverse power be synced in time.  Thats where
the Arduino fails and you would want to do it off the Arduino.  With
ten random variables that don't need to be time related, you can just
let the A/D run continuously and just grab data from the conversion
register when you need it. They run in parallel with instruction
processing so no time slots are lost.


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

email:  bill@...







Re: Coding styles

Jack, W8TEE
 

Yep. Advertised in Dr. Dobbs, Software Development Journal, and Byte. I think we started marketing the compiler in 1983.

Jack, W8TEE


On Monday, May 7, 2018, 2:41:00 PM EDT, Ashhar Farhan <farhanbox@...> wrote:


C88? That was a very very long long ago... I remember ads for it, probably it was in Dr.Dobbs?
- f

On Mon, 7 May 2018, 21:57 Mark Pilant, <mark@...> wrote:
My number 1 rule about coding is:
     Expect / assume someone else will have to modify or maintain the
     code being written.  This means: *comment* the code.

I can't tell you how much I *hate* the statement "the code is the
comments".  Even the code I write for myself, I still put in lots of
comments.  Having them makes it soooo much easier later on when I need
to make changes.

My number 2 rule about coding is:
     Use the same coding style of the existing code when making changes.
     Trying to follow and understand code written using different coding
     styles can be really hard, and lead to misunderstanding and errors.

Probably the best example I have is one piece of assembly code I wrote
years ago.  The code itself was only about 25-30 lines of assembly code,
but there was another page of comments explaining how the code actually
worked because there was a lot of bit manipulation and "odd" instructions
because they were faster than the expected instruction.   (This was the
main protection checking function in the OpenVMS kernel [dating myself]
if anyone is wondering, and it had to be really fast.)

73

- Mark  N1VQW





Re: Coding styles

Jack, W8TEE
 

And I'm off...

Often programmers don't think things like variable and function names make a difference, but it really can affect how easy or difficult it is to read someone else's code. When I was teaching, I found that students tended to use variable names like 'a', 'b', 'c'. Eventually, some guidelines emerged (this was in a C++ course):

1. Variables are nouns, and what they are should be obvious from their name (hatSize, portNumber, vfoFrequency)
    a. Use camel notation, first letter is lower case and upper case for subparts.

2. Methods (functions) are verbs denoting some action takes place within a black box.
    a. First letter of the method name is upper case, then camel notation. (This makes it easier to recognize some programming
        elements, like pointer-to-function rather a pointer variable.)
    b. The name should tell the action performed.
    c. The method name should NOT say how something is done. That is, BubbleSortList() is not so good, SortList() is better.
        The programmer does not need to know how you do something, only what it does and how to interface with it. That way,
        you can change the algorithm within the box and not be lying to its user.

3. Methods (functions) should be cohesive. That is, if you cannot describe what the function does in two sentences or less, it's
    probably trying to do too much. Students tend to write Swiss Army knives and pass in a bazillion parameters to their multi-
    purpose function.
    a. Simpler is better, and enhances the chance for reuse.
    b. If you are passing in 6 or more parameters, either the method is not cohesive, or you need to pass a pointer to some kind
        of data structure.

4. Avoid coupling between methods (functions) as much as possible. That is, one function should do its task without help from
    another methods. Sometimes, coupling cannot be avoided (e.g., you must Open() a file before you can Read() it), but it should
    be minimized as much as possible.


While the above is purely a "style" consideration, it is an important one in that it can make it so much easier to read code.

Jack, W8TEE

On Monday, May 7, 2018, 3:17:30 PM EDT, Art N4EZZ <n4ezz@...> wrote:


Hi,

I normally just sit here and listen to all of you smart folks with the
hope that I can learn something from your discussions, but this trip
down memory lane is too much.

PDP-11/70s, VT-100 terminals and pre-System V Unix the old Version 7,
later all sorts of Unixes and Stratus VOS as well. Yep, I am an old Bell
head.

First screen editor, Emacs, yes I still use it. IDEs, yes although I use
them mostly for compile/debug cycles.

I was for many years a system administrator and typically wrote programs
to accomplish the various utility functions that you would expect. I
also wrote a number of programs to support some rather large conversion
projects.

The scariest words I ever heard in a staff meeting, here is some code
install it on XYZ machine "it should work just fine". Almost always that
translated to "you will spend at least a week getting it to compile and
actually run".

So coding style, don't care but be consistent, if you are consistent I
can figure it out.

Functions and variables should describe what they are used for.

Comments, yes please, if you do something that might be
counter-intuitive then please explain why as well as what.

To finish, something I learned back then about unintended consequences.
After 20 hours working with Bell Labs on a problem in a telephone switch
we found the problem, the fix took about 20 seconds. Before the Bell
Labs guys dropped off the call one of them, I think it was Dennis said,
"you know I wrote that code and I never imagined it could do that".

Thanks for keeping my old mind active and it is back to learning mode
for me.

Art N4EZZ <n4ezz@...>
GnuPG key ID 0x6712DD0E
=============================
Suppose you were an idiot. And suppose you were a member of Congress.
But I repeat myself.
      Mark Twain, a Biography





Re: SWR

Jerry Gaffke
 

Most low power users are 100mW or more.
And 100mW is polite enough when tuning up.

Into 50 ohms, that's sqrt(0.1*50) = 2.24 volts rms of RF, or 3.16 volts peak.
Assuming we keep the 10 to 1 transformer ratio (so can still take readings when at 20W),
that's 0.316 volts for the diode detectors to see when running at 100mW.

I'd think that if the schottky diodes had a bit of forward bias supplied as Art suggested,
they could be working pretty well at 0.316 volts.
Going lower where it's non-linear, could use some of that table lookup flash you had been allocating for the AD8307.

Yes, the germanium stuff is very temp dependent. 

I don't really know how well this diode thing will work on the low end.
But I think 100mW  may prove sufficient for sniffing out an antenna.
Will try to wire this diode detector tandem match up to my Nano, see what it does.

Jerry


On Mon, May 7, 2018 at 11:56 am, Kees T wrote:
I thought the low power levels would be useful for the low power users and not having to forward bias diodes which are still very nonlinear at the low end would be nice. Ge diodes I tested, about 10 types, were VERY inconsistent.....hence the HSMS-2815.


Re: boosting the power on 28 MHz #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

The key there is it a class C final for Drain modulated AM wideband is not needed.
Its close to ideal as class C and bad SWR its likely to be blast proof.

However I've used the IRF640 at HF an input C of 1200pf so I know it can be done as wide band 
if your willing to use a input Z around 4 ohms or less.  Then again ists an 18A 200V device so
with 24V or more it can push serious power.  I've seen more than 100W at 28mhz wide band
push pull.  You need brass tube transformers using ferrite beads and a good ground plane.

Allison


Re: Coding styles

Jack, W8TEE
 

Could be. However, since C is free form, the brace can be on the same line as the if expression, on the line below it, or on a line 40 lines below it...whatever you want. Fortran was a little more rigid in the language structure. I can understand the desire for the "rigidness" as it makes it easier to define the grammar and write the parser.

Jack, W8TEE


On Monday, May 7, 2018, 12:05:39 PM EDT, Tim Gorman <tgorman2@...> wrote:


I've often wondered if the original coding of the "if" statement in C
didn't derive from fortran syntax:

if (expression) then
  statements
endif

The "then" had to be on the same line as the if. In C, the "then" is
replaced by the "{" brace.

At least that's how we had to write fortran in 1968 for the mainframe
to compile it!

tim ab0wr

On Mon, 07 May 2018 05:44:24 +0000
"Ashhar Farhan" <farhanbox@...> wrote:

> 64x16? K&R?? Surely, you are not talking floppy shuffle on the Xerox
> 820 or (jerry pournelle, peace be upon him) a Kaypro?
> BDS C was the only game in town. I brought up a CP/M system for my
> undergraduate project work.
> - f
> - f
>





kd8cec code mod

Richard E Neese <kb3vgw@...>
 

if anyone knows how to reach kd8cec I would like to request a mod in his code to add in cw decode function.