Frequency Hopping experiments on the NRF24 & full tx/rx

[PaulJ]

That takes the biscuit!

Paul

[Spike S]

"... mentioned that tins were used in the 50's and early 60's for homebuilt radios the most chosen tin being an OXO."

I do remember a feature in RCM&E (?) that described a 6 channel reeds Tx built into a tobacco tin. The 27MHz aerial was slightly 'out of scale' ! No doubt someone will produce a pic from that article and an NRF24 could make a great repro.

[James]

Finally I have a 4 channel NRF24 biscuit tin system that works. Tx straightforward although I found header pins are quick but unreliable. Rx was a big problem I used RF NANO code 1913CL set ce9 csn 10 which didn't work so changed to 10, 9 and vice versa 6 times to no avail. After hour here and there over three days I gave up. Today I wired up another RF NANO one with the u.fl aerial addition and connected two New Power XL-9HMB servos and of course jitters and no control. Then connected up a Dynam, Etronix micro to ch 1 & 2 all went well so connected up 2 Futaba 148's to 3 & 4 and they went jitterbugging. After cursing and messing with connections they worked, fantastic.
The New Power servos I tried again but no luck, anyone any ideas?
In meantime my thanks to all who have developed the system and especially Phil G.
What's next.

[James]

I meant to include, in last post, details of the sticks I bought for use in the biscuit tin also note regarding VAT from Aliexpress:-

Radiolink AT9S AT10II Replacement Switch Rod Seat Direction Auto Return Middle Pole / Throttle Non Return Components Accessory|Parts & Accessories| - AliExpress

From 11PM 31 December 2020, AliExpress is required by law to collect UK Value-Added Tax (VAT) at the applicable rate and remit to the UK tax authority when goods are sold to UK customers (i) where the goods are located outside the UK at the point of sale with a consignment value of GBP135 or less, or (ii) where the goods are in the UK at the point of sale, but sold by an overseas seller. For more information, please visit: https://www.gov.uk/guidance/vat-and-ove ... nuary-2021

I bought two sets of sticks a few minutes ago and yes they did add 20% VAT. Things are now more expensive.

[bluejets]

20% wow that's a killer....here in Aus currently 11% but that is certain to change.
Especially now with any recovery from the virus.
Possibly too early just now but, give it a year or two....

[James]

I'm back again. I had a think about the receiver, RF NANO board and all the connections for battery, UBEC, servos etc etc and came up with the idea of adding a piece of veriboard to the NANO. The system works although I only connected up one servo and yet to include the two capacitors. There may be short comings that I'm unaware of due to lack of electrickery knowledge. Photos show what I've done.

[WernerL]

The system works although I only connected up one servo and yet to include the two capacitors. There may be short comings that I'm unaware of due to lack of electrickery knowledge.

That looks perfectly alright! What you have done with the Veriboard is exactly what is going on in a commercial receiver: + and - are routed through all the servo connections, and are tapped-off to feed the electronics.

cheers, Werner

[James]

RF nano aerial any explanations please.
I won't bother with details of how I found this out but suffice to say I didn't switch the biscuit tin on.
Anyway point is I built another RF NANO receiver moved the 0 resistor to 90 degrees, see photo, picked up Tx and connected battery to the NANO twiddled the stick and nothing happened. I removed the aerial picked up Tx and again nothing happened this is when I realised my error fundamental mistake hadn't switched the Tx biscuit tin on. I switched on and with no co axial ufl aerial I still twiddled the stick and the servo responded perfectly. Next day I tried again at about 30m range and all worked (still no ufl aerial plugged in) I couldn't get any more distant but did walk around the front of my house (brick built) and everything still worked despite there being said house between me and the Rx.
I assumed that on re-positioning the resistor the "on board" aerial would not work. Is it perhaps a case that it does and when resistor is biased towards the ufl there are in fact two functioning aerials?

[Phil_G]

Hi James, the track leading from the NRF chip to the empty u.fl socket is sufficient to pick up a signal,
plus 2.4 is such a high frequency that even the tiniest capacitance across a open area of PCB will pass some RF.
Even the NRF chip itself, in its epoxy moulding, will accept RF at close range. Nothing wrong here
Cheers
Phil

[Tobe]

My NRF24-systems, as you might see I have left conversions behind for a full scratch built and yes, I fly with everyone of them w/o any problems also when flying on a frozen lake with temperature of -15 degC.
Top of the line we have my 1+1 - rudder & throttle

Second my GG set 3+1, rudder, elevator with the option of sequential or proportional throttle

Last for the moment my full house set dual stik .

I have included also a few of my actuators and Rx.