Webra Picco and 2.4 GHz conversion with original #1271 actuator.

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MaxZ
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Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

I am getting to convert a Webra Picco Tx to 2.4 GHz for a friend. That in itself I think I can manage, but it turns out he wants to operate the original actuator(s) with it. He has two #1271 actuators and a red cased one (#?).
I am guessing the GG converter described in other topics on this forum will not work with those actuators. Any advise on how to proceed? Frank (tiptipflyer) seems to have done it, Frank?

Cheers,
Max.
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tiptipflyer
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by tiptipflyer »

Yes Max, I am flying the Aeronaut Nova quite often using the Webra Picco transmitter converted with an Orange 2.4GHz module and a Spektrum receiver driving the original Webra Picco actuator by means of an early model Adams pulser module.
viewtopic.php?p=1286#p1286
The Adams pulser is built up from a programmed 12F683 PIC processor from Phil and a MIC4427 mosfet H-bridge instead of the MIC4428 H-bridge intended in the instructions. This MIC4427 non-inverting H-bridge is perfect for the Webra actuator.
Check document P7 in the Archive section of www.singlechannel.co.uk
I am using this setup for several years now without any problems. There was no reason to try the Webra actuator with one of the new GG setups.
"Never change a running system"
Everage flying times are 30min + per flight with power pod and it doesn´t even get warm.
SAM_4250.JPG
SAM_4249.JPG
Frank
MaxZ
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

I have read this topic: viewtopic.php?f=25&t=599&p=4343#p5660 , which seems to be the DIY version of Phil's PIC processor.
All doable I think, but can it be connected straight to the Webra #1271 ? And how, I see just two connecting wires in Frank's picture, is that the standard connection to the actuator?

Cheers,
Max.
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tiptipflyer
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by tiptipflyer »

Yes, the Webra actuator uses only two wires.
Unlike most other actuators, which are on neutral when not under power, the Webra is at full deflection to one side when no voltage is applied.
That makes driving it a little different than most other ones, but it should be possible with the newer DIY versions with a few changes to the sketch,
but I never tried it out.
The Webra actuator will be on neutral at 50% puls rate, full deflection to one side at 0% rate and full deflection to the other side at 100% puls rate.
Good luck with yours
Frank
MaxZ
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

tiptipflyer wrote: 19 Dec 2020, 06:49 Yes, the Webra actuator uses only two wires.
Unlike most other actuators, which are on neutral when not under power, the Webra is at full deflection to one side when no voltage is applied.
That makes driving it a little different than most other ones, but it should be possible with the newer DIY versions with a few changes to the sketch,
but I never tried it out.
The Webra actuator will be on neutral at 50% puls rate, full deflection to one side at 0% rate and full deflection to the other side at 100% puls rate.
Good luck with yours
Frank
Frank, that is exactly what I suspected, the Webra actuator is just like a big relay. Which is why I could not understand this (no critisism intended):
tiptipflyer wrote: 18 Dec 2020, 13:20This MIC4427 non-inverting H-bridge is perfect for the Webra actuator.
The MIC4427 is not a H-bridge, but a dual half-bridge that could be made into a H-bridge by inverting the input signal and connecting it to the second half-bridge (there seems to be a version where one bridge is non-inverting and the other inverting, so you would only have to connect the signal to both inputs). Being a "relay", I guess the Webra does not need a H-bridge. In fact, with a H-bridge it would be powered all the time, just with changing polarity.

I am not saying I am certain about all this, I am just trying to understand. Another thing I would like to know is what voltage is required to power the actuator.

Cheers,
Max.
MaxZ
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

I think I am getting the picture now. Phil's original PIC-based design used a MIC4428YN, which is a dual half-bridge with one non-inverted and one inverted half-bridge. Looking at Phil's instructions I noted that the PIC output is indeed connected to both inputs of the MIC4428YN, making it a full H-bridge.

Frank has chosen to use the MIC4427, two non-inverted half-bridges. By connecting them in the same way to the PIC, he has created dual non-inverted half-bridges in parallel. That suits the Webra actuator perfectly, so all is well. :D

So for the DIY version, I will have to replace the DV8838 full-H-bridge with a MIC 4427, and connect the output of the digispark with both inputs, and the same for the outputs of the MIC, right?

Cheers,
Max.
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tiptipflyer
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by tiptipflyer »

Max, you can explain it much better than I can do.
The Webra actuator is working really well with the MIC4427.
It requires about 9V to run. I used a the 2cell Lipo, which also drives the motor of the power pod, which is adequate.
Here is a little document in englisch regarding the Webra Picco:
WebraPicco1.pdf
(4.45 MiB) Downloaded 162 times
WebraPicco2.pdf
(3.12 MiB) Downloaded 157 times
WebraPicco3.pdf
(442.14 KiB) Downloaded 157 times
WebraPicco4.pdf
(1.27 MiB) Downloaded 165 times
WebraPicco-Schaltplan.pdf
(1.34 MiB) Downloaded 161 times
If there is any interest I do have more info in German language as well as the scematics.
I hope my amateurish explanations were of any help.
Cheers
Frank

Edit:
Das ist alles, was ich über die Webra Picco habe.
That´s all I have about Webra Picco
Last edited by tiptipflyer on 19 Dec 2020, 18:01, edited 2 times in total.
MaxZ
Posts: 330
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Location: Boskoop, Netherlands

Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

Hey Frank,

Thanks for the confirmation and the document. Yes, I would be interested in your German language documents, and so would be my Dutch friends on Modelbouwforum.nl . Reading German is no problem for me and my friends, so please post them here.

Holm- und Rippenbruch,
Max.
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F2B
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Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by F2B »

Bitte, zähl' mich ein. Uhhm, count me in, please. :mrgreen:

Möchte auch sehr gerne diese deutschsprachige Dokumentation einsehen.
Alte Schaltbilder werden ebenfalls immer geschätzt.

Alles Gute,
Bruno
F2B or not to be....
MaxZ
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Location: Boskoop, Netherlands

Re: Webra Picco and 2.4 GHz conversion with original #1271 actuator.

Post by MaxZ »

Hallo Frank,
Ich danke dich für die zusätzliche Deutschsprachige Dokumente und Schaltpläne. Irgendwo sagt es da dass 9V nicht genügt um das Servo ganz zum Spulbekräftigtes Wegende zu bringen wegen Gegenwirkung der kräftige Permanentmagnet , hasst du das auch erfahren?

Gruss,
Max.
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