Tuesday, 16 May 2017
More Spot on 10m
After yesterdays 'success' of a whole one station near Stuttgart spotting my QRPp 10m WSPR signal, im pleased to see that ive been spotted again in the last hour on 10m. This time by G3IGU near Doncaster - around 20 miles away! I suspect this is less to do with a change in propagation and more down to G3IGU turning on a 10m receiver!
Mobile Project Construction
Yesterday, I happened to know I would be sat waiting in the car for an hour, so I decided to take along something to do, other than my Kindle or trawling Facebook,
So I took along a handful of tools, a roll of solder, and a gas powered soldering iron, plus my 2nd Chinese Pixie-2 kit
In order not to set fire to the car, I took a wooden board to work on, with a few screws in to act as a stand for the iron!
The sockets, sounder and crystal socket I had already soldered in previously, so it was just all the small fiddly parts to do in the cramped confines of the drivers seat of a Ford Fiesta!
After a brief 25min soldering session, all but two components were installed. These two turned out to have been supplied the wrong values!
I quite enjoyed doing this, so plan to improve my little 'worktop' by putting a raised edge on it to keep parts from rolling off, and using the router to cut some shallow grooves to put loose components into.
So I took along a handful of tools, a roll of solder, and a gas powered soldering iron, plus my 2nd Chinese Pixie-2 kit
In order not to set fire to the car, I took a wooden board to work on, with a few screws in to act as a stand for the iron!
The sockets, sounder and crystal socket I had already soldered in previously, so it was just all the small fiddly parts to do in the cramped confines of the drivers seat of a Ford Fiesta!
After a brief 25min soldering session, all but two components were installed. These two turned out to have been supplied the wrong values!
I quite enjoyed doing this, so plan to improve my little 'worktop' by putting a raised edge on it to keep parts from rolling off, and using the router to cut some shallow grooves to put loose components into.
Monday, 15 May 2017
DL4YHF CW Keyer Tamed!
With a half hour or so spare this evening, Ive collected up some tools and bits for a little 'out-of-workshop' project building, namely the 2nd Chinese Pixie-2 kit I had kicking about, but also had chance to add the modification resistors to the keyer
This is the 18k series resistor (making 19k with the 1k that is already on the board), and the 39k parallel resistor across the 100k potentiometer.
Well, I havent measured the speed range maximum and minimum yet, but by ear the minimum sounds like 5wpm, the maximum like 40 or 50wpm. And right in the middle of the range are the speeds I want!
I will rig the keyer up to some software later that can tell me the actual speeds, so I can make up a scale for the control. But it seems the mod has done the job.
This is the 18k series resistor (making 19k with the 1k that is already on the board), and the 39k parallel resistor across the 100k potentiometer.
Well, I havent measured the speed range maximum and minimum yet, but by ear the minimum sounds like 5wpm, the maximum like 40 or 50wpm. And right in the middle of the range are the speeds I want!
I will rig the keyer up to some software later that can tell me the actual speeds, so I can make up a scale for the control. But it seems the mod has done the job.
10m WSPR hit!
Sometime over lunch, my WSPR U3S beacon was spotted by DF4UE near Stuttgart. Conditions on 10m at the moment are practically dead! So, thats not a bad result for around 150-200mW!
DL4YHF CW Keyer - Taming the speed control?
Ive had a quick chat with Wolfgang DL4YHF by email regarding the speed range of the keyer. As suspected, the speed control range cannot be easily changed in the code, so the best plan of attack is to modify the resistance range of the control.
Yesterday I measured the resistance at my preferred slowest speed (just before the control becomes unresponsive) as 47k, and that at my preferred maximum speed (probably about 45wpm) as 18k.
The fast speed is the easy part to deal with. By assuming the pot to be at zero, then its a case of replacing the 1k input series resistor with an 18k unit. But the slow limit is more difficult. The resistance difference range needed from the pot is 29k - of course no such pots exist.
Rather than replace the 100k pot that is in place, the answer is to parallel it with another fixed resistor to modify the range. In this case, a maximum value of 29k can be achieved by paralleling the potentiometer with a fixed resistor of 39k.
I will try this tonight and see if I get an acceptable control range. Replacing the 1k resistor would entail removing a number of wire connections to get the PCB out, so instead I will probably keep it in circuit and add the 18k in series with it. I doubt the extra 1k will make much difference to the speed range.
Yesterday I measured the resistance at my preferred slowest speed (just before the control becomes unresponsive) as 47k, and that at my preferred maximum speed (probably about 45wpm) as 18k.
The fast speed is the easy part to deal with. By assuming the pot to be at zero, then its a case of replacing the 1k input series resistor with an 18k unit. But the slow limit is more difficult. The resistance difference range needed from the pot is 29k - of course no such pots exist.
Rather than replace the 100k pot that is in place, the answer is to parallel it with another fixed resistor to modify the range. In this case, a maximum value of 29k can be achieved by paralleling the potentiometer with a fixed resistor of 39k.
I will try this tonight and see if I get an acceptable control range. Replacing the 1k resistor would entail removing a number of wire connections to get the PCB out, so instead I will probably keep it in circuit and add the 18k in series with it. I doubt the extra 1k will make much difference to the speed range.
Saturday, 13 May 2017
Building the DL4YHF Keyer
Having got the DL4YHF PIC CW Keyer working on breadboard, the next step was of course to make it a permanent build. I had already decided on the box I wanted to use, a small beige plastic one i'd picked up somewhere, and decided to use perfboard and hard wire the circuit, rather than muck about trying to design a PCB or waste my stock of Veroboard.
My first task then, was to size a piece of perfboard to fit the box. To do this two rows of holes needed to be removed, and the sides filed, plus the corner cut-outs. This allowed the board to fit easily down in the bottom of the box. I also decided to use a socket for the PIC chip, but couldnt find any 18pin DIL sockets, so had to bodge one from a couple of the 14pin sockets ive loads of. But probably the most important task was to search my junk boxes to find a holder for a 3v coin cell! The one I found was surface mount, but a few spare PCB pins soon had it in place.
Of course, after the build was complete, and while looking for something else entirely, I happened to find a load of 18pin DIL sockets!
The wiring on the underside is all point to point, mostly using the legs of the components themselves.
With all the components installed, I checked it fitted the box, then drew out the circuit from the board, to make sure I hadnt missed anything or got anything wrong. This is well worth doing, but only practical for small projects. In the event, I'd missed a critical connection - the Vss line to the PIC!
The final underside wiring is shown below. Im quite pleased that I managed to find a layout that had all the components on one side, as that meant the board would fit as low in the box as possible, giving me more space to work with. At this point I connected the board up to the speed control pot using croc clip leads and tested the keyer to make sure it was working.
So next came the work on the box itself. I was making the layout up as I went along, and the case and controls layout was no exception. A lot of work with files was needed, as I wanted to add a slide switch to allow me to turn off the sidetone. I also had to be careful where the output connectors went so as not to short the battery!
The 3.5mm stereo jack socket for the key caused trouble. The cheap ones i'd got proved that you get what you pay for! The act of tightening it up caused the damn thing to distort out of alignment such that I couldnt get a plug in! It took me quite a while to figure this out and correct it!
So with the board in place and the wiring ready, I turned my attention to the top panel. Initially I thought I would have to leave the project only part finished as I could only find one panel mounting push button. But I then decided to use a pair of very nice looking but PCB mounting square tactile buttons. This meant a lot more file work to create the square cutouts!
The buttons themselves had to be secured with hot-melt glue - trouble is, ive run out! So, I searched the workshop, salvaging little bits here and there, until I had enough to secure the two buttons. The speed control pot is also secured using its anti-slip stud - this involved some very careful drilling of 1.5mm blind holes!
The filed cutouts are not the neatest but are reasonably square and with the buttons in place dont look too bad. The light blue caps of the buttons go nicely with the beige colour of the box.
The final component to fit was the LED, which is used by the chip to indicate various special states. Everything was then tested again, before finally screwing up the box and adding a control knob.
And here it is, connected to my Hi-Mound paddles. The volume level of the sidetone is rather low, even with the sound holes drilled in the side, but its adequate.
I now need to build the cables to connect it to my radios! The speed range is a bit wide for my purposes, but thats something to sort out at a later date. Ive found a spot which gives around 8-12wpm, which is where I want it.
My first task then, was to size a piece of perfboard to fit the box. To do this two rows of holes needed to be removed, and the sides filed, plus the corner cut-outs. This allowed the board to fit easily down in the bottom of the box. I also decided to use a socket for the PIC chip, but couldnt find any 18pin DIL sockets, so had to bodge one from a couple of the 14pin sockets ive loads of. But probably the most important task was to search my junk boxes to find a holder for a 3v coin cell! The one I found was surface mount, but a few spare PCB pins soon had it in place.
Of course, after the build was complete, and while looking for something else entirely, I happened to find a load of 18pin DIL sockets!
The wiring on the underside is all point to point, mostly using the legs of the components themselves.
With all the components installed, I checked it fitted the box, then drew out the circuit from the board, to make sure I hadnt missed anything or got anything wrong. This is well worth doing, but only practical for small projects. In the event, I'd missed a critical connection - the Vss line to the PIC!
The final underside wiring is shown below. Im quite pleased that I managed to find a layout that had all the components on one side, as that meant the board would fit as low in the box as possible, giving me more space to work with. At this point I connected the board up to the speed control pot using croc clip leads and tested the keyer to make sure it was working.
So next came the work on the box itself. I was making the layout up as I went along, and the case and controls layout was no exception. A lot of work with files was needed, as I wanted to add a slide switch to allow me to turn off the sidetone. I also had to be careful where the output connectors went so as not to short the battery!
The 3.5mm stereo jack socket for the key caused trouble. The cheap ones i'd got proved that you get what you pay for! The act of tightening it up caused the damn thing to distort out of alignment such that I couldnt get a plug in! It took me quite a while to figure this out and correct it!
So with the board in place and the wiring ready, I turned my attention to the top panel. Initially I thought I would have to leave the project only part finished as I could only find one panel mounting push button. But I then decided to use a pair of very nice looking but PCB mounting square tactile buttons. This meant a lot more file work to create the square cutouts!
The buttons themselves had to be secured with hot-melt glue - trouble is, ive run out! So, I searched the workshop, salvaging little bits here and there, until I had enough to secure the two buttons. The speed control pot is also secured using its anti-slip stud - this involved some very careful drilling of 1.5mm blind holes!
The filed cutouts are not the neatest but are reasonably square and with the buttons in place dont look too bad. The light blue caps of the buttons go nicely with the beige colour of the box.
The final component to fit was the LED, which is used by the chip to indicate various special states. Everything was then tested again, before finally screwing up the box and adding a control knob.
And here it is, connected to my Hi-Mound paddles. The volume level of the sidetone is rather low, even with the sound holes drilled in the side, but its adequate.
I now need to build the cables to connect it to my radios! The speed range is a bit wide for my purposes, but thats something to sort out at a later date. Ive found a spot which gives around 8-12wpm, which is where I want it.
Friday, 12 May 2017
10m WSPR today, wonder if i'll get any spots?
Put the U3S on 10m WSPR this morning. So far, not one spot. This of course is not unexpected, but hopefully there might be a little bit of Es at some time. Just one spot of my 200mW would be nice!
Friday, 5 May 2017
100 common words file for IZ2UUF CW Trainer
Some of you, like me, might want to use the feature in IZ2UUF's Android CW trainer app to play words from file. But, likely like me, your having difficulty finding a suitable file, and getting it loaded in!
Below is a list of the 100 most common words in English. Copy this and past it into notepad. Save it as 100.txt
Then transfer it to the cw folder in your android devices internal storage. Not the SD card! The path shown in the app doesnt seem to be right, so you will need to find the folder using a file viewer app.
Have fun!
the be to of and a in that have I it for not on with as you do at this but his by from they we say her she or an will my one all would there their what so up out if about who get which go me when make can like time no just him know take people into year your good some could them see other than then now look only come its over think also back after use two how our work first well way even new want because any these give day most us
Below is a list of the 100 most common words in English. Copy this and past it into notepad. Save it as 100.txt
Then transfer it to the cw folder in your android devices internal storage. Not the SD card! The path shown in the app doesnt seem to be right, so you will need to find the folder using a file viewer app.
Have fun!
the be to of and a in that have I it for not on with as you do at this but his by from they we say her she or an will my one all would there their what so up out if about who get which go me when make can like time no just him know take people into year your good some could them see other than then now look only come its over think also back after use two how our work first well way even new want because any these give day most us
Monday, 1 May 2017
Musings on the Keyer
The one thing that im a little concerned about with the DL4YHF keyer, is the speed control. Designed to give operating speeds of around 6 to 40 words per minute, ive found that around a third of the track of my 100k control pot has no effect, and the range of speeds likely to be usable to me (the 8 to 25 wpm) are covered by a relatively small rotation of the control.
I found out from a bit of research that the speed control is non-linear. I could try a log pot to see if I can cancel out the non-linearity inherent to the design. But probably a better way would be to determine the resistance either end of the range that is useful to me, and redesign the pot and its series resistor to give me just that range of resistance across a full rotation of the control.
I found out from a bit of research that the speed control is non-linear. I could try a log pot to see if I can cancel out the non-linearity inherent to the design. But probably a better way would be to determine the resistance either end of the range that is useful to me, and redesign the pot and its series resistor to give me just that range of resistance across a full rotation of the control.
DL4YHF CW Keyer prototyped
With a bit of spare time this afternoon, and with Bob M1BBV sending 'do it!' messages to me, I got the CW Keyer prototyped onto breadboard. It would have been easy to go straight to PCB with this, but I wanted to prove the PIC chip had programmed correctly first.
Ive tried it on both 5v and 3v supplies with no issues, so due to the extremely low current drain, I will probably fit a holder for a 3v lithium coin cell in the finished, boxed keyer. My only issue with it is that there is a large part of the potentiometer track that seems to have no effect on the speed adjustment, meaning that the speed, especially slow speeds, is a bit tricky to set. Im sure i'll find a way around that though. I even managed to find a genuine old 2N2222A in a TO-18 package for the keying output!
The project is so simple that I will probably build it on a simple perforated prototype board, even Veroboard is a bit overkill for this! I have a nice little beige-grey plastic box to build it into. Extra to the schematic parts will be the coin cell holder, and connectors for the paddle key and radio. Both connectors will be common 3.5mm stereo jack sockets. The PIC will go in a DIL socket.
If your wondering what the extra parts to the left are for - thats another project! I also have an IR remote control tester prototyped on the same breadboard!
Following on from the above prototyping, Ive removed the 330pF and 3M3 resistor, as these are not needed by the firmware version im using, which uses internal settings for the clock. However, I still need to add in another 22k and 2N2222A to provide the QSK output (used to give a PTT to radios without their own in-built QSK, the FT-290Rmk1 being just such a set). A switch will also be added to turn the sidetone on/off as required.These are shown in the circuit diagram above.
Ive tried it on both 5v and 3v supplies with no issues, so due to the extremely low current drain, I will probably fit a holder for a 3v lithium coin cell in the finished, boxed keyer. My only issue with it is that there is a large part of the potentiometer track that seems to have no effect on the speed adjustment, meaning that the speed, especially slow speeds, is a bit tricky to set. Im sure i'll find a way around that though. I even managed to find a genuine old 2N2222A in a TO-18 package for the keying output!
The project is so simple that I will probably build it on a simple perforated prototype board, even Veroboard is a bit overkill for this! I have a nice little beige-grey plastic box to build it into. Extra to the schematic parts will be the coin cell holder, and connectors for the paddle key and radio. Both connectors will be common 3.5mm stereo jack sockets. The PIC will go in a DIL socket.
If your wondering what the extra parts to the left are for - thats another project! I also have an IR remote control tester prototyped on the same breadboard!
 | |
| DL4YHF PIC CW Keyer using 16F628A with Semi-QSK Firmware |
Following on from the above prototyping, Ive removed the 330pF and 3M3 resistor, as these are not needed by the firmware version im using, which uses internal settings for the clock. However, I still need to add in another 22k and 2N2222A to provide the QSK output (used to give a PTT to radios without their own in-built QSK, the FT-290Rmk1 being just such a set). A switch will also be added to turn the sidetone on/off as required.These are shown in the circuit diagram above.
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