Other SOTA sites: SOTAwatch | SOTA Home | Database | Summits | Video | Photos | Shop | Mapping | Sotlas | FAQs | Facebook | Contact SOTA

Homebrew touch paddle for less then 10€

Equipment
#1

I would like to introduce you to my latest homebrew project. A contactless cw paddle for less than 10 euros.

The circuit requires two contacts each, which are connected by the skin resistance. Since I hold the key in my hand while keying on the summit and touch one contact, touching the second contact is sufficient. If you have very dry skin, some saliva or a higher summit will help. :sweat_smile:

I get the operating voltage of the circuit from the trx, because the current devices have a switching voltage of 3.3-5V at the key input. This voltage switches the transistor through when touched and the symbol is sent. The capacitor C7 (why not C3 :face_with_raised_eyebrow:) holds the charge even when keying and R1C1 / R2C2 block the RF.

73 Chris

TinyTouchKey03
TinyTouchKey031462×930 74.4 KB

TinyTouchKeyInside03
TinyTouchKeyInside032265×3304 740 KB

18 Likes
#2

Very clever Chris. I would like to try one of those please. Do you have an online shop etc.
Best 73

#3

Unfortunately nothing like that.
73 Chris

1 Like
#4

I have built my version of this little critter and it works!

I will take it to the summits and test it in the field. I have my doubts that it will key reliable in cold or rainy weather, but let’s see! I will report back. It definitely needs some spit on the finger tips to key accurately.

The big advantage of this design is that it runs without a battery. One item less that can fail. It is also light weight. If I stick with this keyer I would build another one with smaller resistors (the 22MOhm are 5W), eventually with SMD components to see how light it can get.

Nice project!

73 Heinz

OE5EEP_20211013_BM2021_02
OE5EEP_20211013_BM2021_024020×2810 832 KB

4 Likes
#5

Hello Chris,
Thank you for sharing the circurit-design. Now I Have build my own touch-
paddel, work’s fine on every rig and keyer I have. It is the first build and I try
to build a premium version soon. It’s ideal for portabel OP’s and weight is
only 17-18 gramms. I will do some heavy weather testing(Rain,snow and
cold)to see, if it works under bad conditions. But up to now it’s perfekt for
me, without a Battery that’s the best…

73 Thomas DD4EA

20211022_110811
20211022_1108111944×2592 674 KB

20211022_110800
20211022_1108002592×1944 680 KB

20211022_110750
20211022_1107502592×1944 647 KB

20211022_110745
20211022_1107452592×1944 634 KB

5 Likes
#6

After many cw qso at the summit, I only use them.

Sometimes it doesn’t seem to work properly, but it turns out that my brain was the problem.

I call this spontaneous Morse dementia :sweat_smile:.
73 Chris

4 Likes
#8

Hello Chris,
Yes, I have got the same disease, now I have a correct diagnosis. What a laugh, change key’s won’t help in my opinion, but I carry always a spare key in
my pack. Few years ago I build a singlepaddel from bicylespokes(I am a cylist all my live), once adjustet work’s very fine. I show you my keys for outdoor use.
By the way, your guitarplaying on a song for guru, was very good. I like your
Improvisations and the feeling, that reached me.

73 thomas

20220109_115257
20220109_1152572592×1944 892 KB

20220109_115240
20220109_1152401944×2592 993 KB

dd4ea

3 Likes
#9

Wenn der Funker nicht schwimmen kann, dann liegt es an der Badehose.
If the radio operator can’t swim, it’s because of the swimming trunks.
:laughing:
73 Chris

2 Likes
#10

I’m one of those with a very dry skin and after trying one of those several years ago, I found these type of paddles don’t work for me, so I’ll keep using my Palm paddle or some of my homebrewed ones with metal-to-metal electrical contacts.
The use of saliva on my keying fingers is something I don’t want to do or depend on.
But I’m glad it works for you and others. I wish you a good success and lots of SOTA QSOs with it.
Thanks for sharing your project here.
73,

Guru

#11

The recent versions designed by VK3IL are based on detecting even very low levels of pressure on the paddle, not capacitance or conductance via moisture on the fingers. I have my kit waiting to be built and will let you know how it goes.

73 Andrew VK1DA

2 Likes
#12

I understand this very well and it’s definitely odd.
Hope to hear you today, All the best, Guru
73 Chris

1 Like
#13

Thanks for the pictures of your prototype. What contact buttons have you used?

1 Like
#14

I have also been using the VK3IL version (V1) for a few years now…Flawless…in any WX.
Tim - K5DEZ

1 Like
#15

I use allen screws (Inbusschraube) 3mm with a nut outside.
73 Chris

1 Like
#16

Hello DH5ST,
I used 3X 1 CENT- COINS and soldered a wire on the other side, see the pic’s
Please, the wire goes inside to the pcp.
73 Thomas

1 Like
#17

Thank you!
In the second set of pictures somehow it does not look like CENT coins.
Didn’t see the first set of pictures - sorry

73s
Ingo

#18

I was able to improve my contactless key with. A small lithium button cell has significantly improved the sensitivity. The current through the battery is in the range of 0.0001 mA and should last for decades.

Here is a size comparison. Sometimes I miss the cheat sheet on the PalmPaddle. :sweat_smile:
73 Chris

TinyTouchKey04
TinyTouchKey041097×693 70.7 KB

Tiny3keys
Tiny3keys800×635 55.9 KB

73 Chris

4 Likes
#19

Everything wonderful… but I can’t help myself…

I love the mechanics - and morse is still the most beautiful for me when you bring 2 contacts together mechanically.

I feel the same way about wristwatches… although it’s less accurate than a quartz watch, I love my automatics. :innocent: :blush:

73 Armin

3 Likes
#20

Ahhhhh the brilliance and creativity from the SOTA team
John VE3IPS

2 Likes