Go Down

Topic: RF Signal 40.6835MHz (Read 176 times) previous topic - next topic

quiddi

Hi everybod,

I want to read and send 40.6835MHz signals with an Arduino. Has someone done it before?

My first idea was to buy a send receive kit for 433MHz and switch the crystal to a 40.6835 one on the sending unit. Do you think that's possible? The second problem is then, how to receive the packages.

Any ideas?


jremington

Possible, but it probably won't work.

Why do you want to send on that frequency? Is it legal to do so in your country?

Geek Emeritus

RF circuits use a thing called a tank. a tank passes a certain frequency and eliminates all others. a tank is composed of a coil and a capacitor.

changing the crystal will just move your RF oscillator to a frequency rejected by the tank
All PMs will be deleted unopened due to arrogant argumentative pot stirring Malfoys.
 If you have not read "How to use this forum - please read", in particular: "7. If you are posting code or error messages, use "code" tags":  expect rude responses

Grumpy_Mike

Quote
I want to read and send 40.6835MHz signals with an Arduino. Has someone done it before?
No. That is a really odd frequency.

Quote
My first idea was to buy a send receive kit for 433MHz and switch the crystal to a 40.6835 one on the sending unit. Do you think that's possible?
No. The other component values you will have to use ensures that you will need a total redesign. And some expensive test kit to test it.


slipstick

The only thing I know of operating around that frequency is Radio Control in some countries (including the UK for surface models only). But whatever it is you're doing you're going to need to know a lot more about the RF signal than just the carrier frequency.

Steve

Paul__B

In short you need to purchase the ready-built transmitter for that frequency.  This has little or nothing to do with an Arduino but should be self-evident.

Yet another example of  the simple-minded "you can do anything with an Arduino" meme.  Too much time spent on "instructables" perhaps?  :smiley-roll:

MarkT

#6
Apr 21, 2019, 02:22 pm Last Edit: Apr 21, 2019, 02:23 pm by MarkT
Hi everybod,

I want to read and send 40.6835MHz signals with an Arduino. Has someone done it before?
Do you mean 40.685MHz garage door opener?   If so get a garage door sender and receiver
and hack into them?
Quote
My first idea was to buy a send receive kit for 433MHz and switch the crystal to a 40.6835 one on the sending unit. Do you think that's possible?
Not in the slightest, completely different band, radio circuits are narrow-band tuned circuits that have a
small amount of frequency flexibility only.  Not to mention the SAW filter.
Quote
The second problem is then, how to receive the packages.

Any ideas?
There's always SDR of course...
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

Go Up