Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?

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Hi there,

i use at moment for 433Mhz the Arduino Nano and “Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver” (http://www.ebay.de/itm/Geeetech-433Mhz-Superheterodyne-3400RF-Transmitter-and-Receiver-Link-Kit-Arduino-/381199588108?hash=item58c1441b0c:g:x-kAAOSwWxNYtjbZ) with 5V over the Arduino Nano.

In the description there say:

TX Technical Specifications:
Working voltage: 3V~12V
Working current: max40mA (12V), min9mA(3V)
Resonance mode: sound wave resonance (SAW)
Modulation mode: ASK /OOK
Working frequency: 433.92MHz
Frequency error: +150kHz (max)
Velocity: 10Kbps
Self-owned codes: negative
Aerial Length: 18cm(433.92MHz)

RX Technical Specifications:
Working voltage: 5.0VDC +0.5V
Working current:2.5mA (5.0VDC)
Working principle: superheterodyne
Working method: OOK/ASK
Operating frequency: 433.92MHz,
Sensitivity: excel –105dBm (50)
Velocity:
Output signal: TTL electric level signal entire transmit

Package Included:
1 x 433Mhz 3400 RF Transmitter & Receiver Kit

So i buy also this: http://www.ebay.de/itm/152329539855?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

And a 23A Batteriy with 12V…

Then i soldered “jumper Kabels” on the Battery holder (I had isolated it but after its not worked i checkt the connection again)

(i had testet my Battery holder with a Remotecontrol of one of my 433Mhz Sockets… the Remotecontrol work with it)

Then i switch of the Cables with 5V from the Arduino and plugin my 12V Battery but the Transmitter will not work with it. if i switch it back to 5V it works well … has anyone tried this before?

My Test (working Build) at the Moment:

(its same the cabling like here https://forum.pimatic.org/topic/202/4-homeduino-433-mhz-sending-receiving-and-even-more )

Noboby a idea?

@tehmilcho said in Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?:

Noboby a idea?

Could depand on the type of battery you use. It might say 12v, but it can output 13,5v!

In that case, dont be surprised if you fry your transmitter. Why not use 5v?

@Gleno0h

hey want to use 12V for more Range… and i use a “Duracell MN21 V12”(https://www.amazon.de/dp/B002NRQO2Q?psc=1) its the same like in the standard 433Mhz Remote Controllers.I tried also a battery of my 433mhz Remote controller without success.

@tehmilcho said in Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?:

@Gleno0h

hey want to use 12V for more Range… and i use a “Duracell MN21 V12”(https://www.amazon.de/dp/B002NRQO2Q?psc=1) its the same like in the standard 433Mhz Remote Controllers.I tried also a battery of my 433mhz Remote controller without success.

Its a Alkaline battery, which still can give a bit more current then 12v.

I am by no means an expert on using battery’s so maybe someone else knows the answer.

Is it possible to try a lower voltage battery?
This way you are sure the batteryholder is not the problem.

As an alternative for range extending you might want to look into using “ESPimaticRF”.

For that you would need minimal 2 NodeMCU’s and 1 send/receive kit.

ESPimaticRF sends RF through your wifi so you can place it anywhere you want.

The great thing is that you can add another NodeMCU with an RF kit if the range isnt enough!

I have pimatic upstairs and 1 rf device in the livingroom and 1 in the backyard, works perfect.

@Gleno0h

mhh that can be a reason … i ordered today a 9V block and connectioncable for it… we will see if this will work!

Maybee it don’t work because the arduino can handle only signals up to 5V and the Sender wants 12V pegel if the power supply is also 12V?
If so you have to switch 12V with a transistor who is controlled by the arduino.

@V1per

Thats the normal build:

And thats what i tried:

So the Arduino has just to handle the Data… this should be work or im totally wrong?

If I’m right with my purpose the purple wire must also gives a 12V Signal when you power the transmitter with 12V.
If so you have to use a transistor (a BC457 or BC458 can do the job) and wire it like this:

• purpel wire to a 33KOhm resistor, the 33Ohm restistor to the base of the transmitter.

• also from the Base a 100KOhm resistor to ground
• the emiter goes to TX or RX on the transmitter
• and on the colector you wire a 1k5Ohm resistor
• at the 1K5Ohm tesistor you wire the +12V

But if you do this be sure that the transmitter can handle 12V on TX/RX.

Its similar to this the only change is that the emiter don’t go to ground but tu TX or RX.

mhh well i think @V1per must be right… i tested today with a 9V Block… same im not able to send. if i switch back to 5V, its worked fine! Or the Transmitter Details are wrong…

@tehmilcho the ground (black) from the 12v battery should also be connected to the arduino ground, now there is no potential difference for the signal wire (purple)

@sajo ahh… just that i understand it right… you mine like this?

Now its works… yippie … @sajo Thanks alot, you are awesome!

@tehmilcho That’s great. Please keep us posted about your results! In particular, I would like to know if transmission range has improved in your setup. I read controversary posts about the matter and there was no conclusion, really.

Did you also consider de-noising the power rail with capacitors? Just wondering as this improved the range in my setup.

@tehmilcho Yep, thasts correct!

@mwittig What type and values of capacitors did you use? Perhaps it is interesting for my setup as well. Is it for the transmitter or the receiver?

@tehmilcho Did the range increase with your modification?

Mhh i cant say how mutch better the performance / range now are because it have the same Problem. My Switches will sometimes not work proper… but there just 3-4m from the Transmitter away… so i thinked maybe is the signal to weak. But i if have the same Problems with 12V… i think now it must be a problem with the antenna or other sources of interference because i have the Raspberry, my NAS and my Fritzbox (router) in a small cabinet…

@rikki78 said in Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?:

What type and values of capacitors did you use? Perhaps it is interesting for my setup as well. Is it for the transmitter or the receiver?

I am using a 100nF ceramic and a 10uF electolytic capacitor on the power rail. The gain is on the receiver side, basically, but it may also improve the receiver side. See also the following diagram from http://www.nemcon.nl/blog2/wiring which suggested using three capcitors. I haven’t used the aliminium foil as my receiver is shielded.

@rikki78 said in Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?:

@tehmilcho Did the range increase with your modification?

little update… i removed my antenna now completely and it works perfect in my whole Apartment (64qm) with 12V.

@tehmilcho said in Geeetech 433Mhz Superheterodyne 3400RF Transmitter and Receiver - with 12V?:

little update… i removed my antenna now completely and it works perfect in my whole Apartment (64qm) with 12V.

What kind of antenna did you use? Did you keep the antenna on the receiver?