Picaxe touch sensor for ham CW keyer?

JohninZona

New Member
I am looking at using a picaxe in a CW keyer for ham radio use. I built a CW keyer using an 08M2 a couple of years back and it works great using an external paddle, but I would like to try making a touch keyer. Has anyone used picaxe "touch" feature for a CW keyer? I am mostly wondering if the touch inputs would be too
sensitive since they don't actually have to be touched to work, i.e. sensing proximity instead of actual physical contact....which would likely lead to a lot of keying errors.....my CW fist is bad enough...I don't need anything to make it worse :) Anyway, I would welcome feedback from anyone who may have used a picaxe in a CW touch keyer application. Thanks and 73, W5EEX in Phoenix, AZ.
 

premelec

Senior Member
QLF? ;-0 - I suspect your best prospect would be to use interleaved V- and touch lines on an etched paddle - give it a test... 73
 

techElder

Well-known member
Touch can be made as "touchable" as you want by adjusting parameters.

Or, you could make a "squeezable" paddle where you are depending on the durometer value of a flexible material to get you closer / further away from a touch pad.
 

JohninZona

New Member
QLF? ;-0 - I suspect your best prospect would be to use interleaved V- and touch lines on an etched paddle - give it a test... 73
QLF? ;-0 - I suspect your best prospect would be to use interleaved V- and touch lines on an etched paddle - give it a test... 73
Premelic,
QLF....Hi Hi.....if I sent with my left foot NOBODY would ever be able to copy me....thanks for the reply...still collecting inputs before I try a touch keyer project. -73
 

erco

Senior Member
Interesting idea, but being a ham with some keyer experience plus being a Picaxe user with some touchpad experience tells me it will likely be tough to calibrate & use. Typically, keyer paddles don't travel very far, and the spring preload is adjustable to suit tastes. I keep touch contact with both paddles in use, which wouldn't work with touchpads. The touchpad values can vary based on finger proximity, even without direct contact, so again, getting the threshold values for touch vs no-touch might be tricky. But more power to you if you give it a whirl, I'd love to see you do it!
 

premelec

Senior Member
Seems likely what is needed is pressure sensitive set up - perhaps touch with some thin foam pad & foil could work - I doubt "air paddle" without actual contact pressure on paddle would satisfy [but then I still have a Vibroplex... can send half dots and such - ;-0 ]
 

nevmarr

New Member
Hi JohninZona. I've been tossing the exact same idea around in my head and came up with the exact same questions. Would the touch be too sensitive, and potentially need to be autocalibrated or recalibrated on each use due to environmental issues? How did you get on with your experimenting?
 

erco

Senior Member
Has anyone made a plain (non-touch) CW keyer? Would be a great 08M2 project. I'm old-school, some 40 years ago I built a multi-IC keyer kit which I got from a hamfest, based on WB4VVF's 1973 Accu-Keyer, which worked great. Nice options including auto-space, etc. Funny that an 8-pin Picaxe could easily outdo that fairly complicated circuit.

http://www.arrl.org/forum/topics/view/2163
 

premelec

Senior Member
I've built many keyers from vacuum tubes to all relay & capacitor types in past... recently [Jan 2017?] there was a keyer with same PIC chip as 08M "Hamcrafters K16-EXT Kit" described in QST. Has LOTs of fancy features and configurable options... I don't recall if HEX files available etc... but just reading the features is impressive... 73

added: https://www.hamcrafters2.com/K16IC.html
 
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Has anyone made a plain (non-touch) CW keyer? Would be a great 08M2 project. I'm old-school, some 40 years ago I built a multi-IC keyer kit which I got from a hamfest, based on WB4VVF's 1973 Accu-Keyer, which worked great. Nice options including auto-space, etc. Funny that an 8-pin Picaxe could easily outdo that fairly complicated circuit.

http://www.arrl.org/forum/topics/view/2163
I've made several over the year, including one with auto-incrementing serial numbers for CW contest operation - that used a 28X. More recently I have used the 08M2. I use a Kent single-paddle key

Richard
 

nevmarr

New Member
I've made several over the year, including one with auto-incrementing serial numbers for CW contest operation - that used a 28X. More recently I have used the 08M2. I use a Kent single-paddle key

Richard
I'm in thought process mode at the moment. I don't chase contests but like the idea of the auto-increment … I guess everyone is 599 and the whole cypher is auto? Any other ideas I should consider?

I'm currently thinking this might drive a 08M2 keyer ... https://m0ukd.com/homebrew/capacitive-cw-touch-key-circuits/
 
The auto-increment facility in my PICAXE-based CW keyer does depend on using the "search and pounce" mode of contest operation, which is how I usually operated in CW contests ten years ago. At the coding stage I didn't consider whether it would increment correctly when "running" i.e. calling CQ to invite replies. It may do - I will have to check it out.

These days I use a netbook running contest logging software and this also sends CW - my job is just to enter call signs and serial numbers or other data as required. I do use a home-made CW transceiver that incorporates seven PICAXEs, which I hope demonstrates brand loyalty.

Richard
 
Sorry but I don't have any means of recording video and I do not use social media. I'm quite happy to share my software. This is written specifically for my projects rather than for a general purpose keyer, such as those sold commercially.
 
I would be interested in having a look to see how you handle timings in your keyer software.
Firstly, the start of the first dot or dash should be asynchronous, and by that I mean that there shouldn't be a regular clock running that determines when the dot or dash actually starts. My first keyer, made from discrete components decades ago, had such a clock, which would have made it more difficult to use. Secondly there needs to be a dot and dash memory so that if the next keying action is to change from a dash to a dot or a dot to a dash, then this is stored as soon as the present dot or dash is started.

To give an example. If you slow down the CW speed to, say, less that 12wpm, and then make the paddle movements for the letter "N" (dah-dit) as quickly as possible (so quickly that it is still sending the dash when you have already completed the paddle actions for both the dash and the dot), then it should send an"N". A keyer that just send a "T" (dah) doesn't have a dot and dash memory. All the commercial keyers and transceivers that I have tried do this correctly.

As I recall, the keyer in my home-made transceiver takes perhaps 10ms before it looks for a change from dot to dash and vice-versa, but that it fast enough. Please note that my keyers do not support the IAMBIC modes.

Richard
 
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