IR Jammer Circuit not working

[sneitzke38]

I am using the extech multimeter kit and just got it the other day so the batteries are new

 

[aliraza786]

and simulator...??

 

[sneitzke38]

What do you recommend that is good? Is ltSpice Good?

 

[tsvetelin_velkov]

did you tried to measure the components that you have on the board, just disconnect one leg and try to measure ( disconnect the power supply first! ). sometimes the markings can create confusion, sometimes when you have many components on the table you can pick up a wrong one ... such mistakes happen a lot ... make sure that all components are with the correct values, compare your schematic with those proposed by other people who try to help you - your schematic is very simple and strait forward, there should not be many possibilities for a mistake.
and last but not least - check you multimeter, frequency meter against a known frequency source - open an electronic watch, crystal driven - there is a crystal oscillator working there and it is 32 kHz. if your reading is much different ( more than 5%, ( I know - 5% error is too big, but this is just to give enough margin ) ), it is the measurement unit not the schematic.

 

[sneitzke38]

check you multimeter, frequency meter against a known frequency source - open an electronic watch, crystal driven - there is a crystal oscillator working there and it is 32 kHz. if your reading is much different ( more than 5%, ( I know - 5% error is too big, but this is just to give enough margin ) ), it is the measurement unit not the schematic.

Could i Use a TV remote with a known frequency?

---------- Post added at 22:00 ---------- Previous post was at 21:49 ----------

Just tested all of the components and it seems the only mix up was a 560-Ohm resistor in place of a 470-Ohm

 

[tsvetelin_velkov]

yes, you can try the remote also, the only thing is that you don't know what is actually the frequency. could be that it is one of the standard for IR remotes, but could be also that your remote is using some non standard parts. you never mentioned what kind of device you are trying to jam

 

[sneitzke38]

you never mentioned what kind of device you are trying to jam

Oh sorry forgot about that it's a Samsung TV

 

[tsvetelin_velkov]

ok, tv sets are common and it is easy to find service manuals for them, you can try to find the service manual / schematic in Internet, then try to locate the IR receiver in the schematic, then find the part in Internet, datasheet will give you information about the frequency and also other useful things. It could be a bit complex for you, and it will take some time, but as much you try to read and understand as easier it will become with time ...

 

[sneitzke38]

Hmm Samsung is incredibly secretive about their components but will still look

---------- Post added 06-09-11 at 00:03 ---------- Previous post was 05-09-11 at 23:46 ----------

But im still wondering what i should do with pin 7 and why im getting 100khz?

---------- Post added at 00:17 ---------- Previous post was at 00:03 ----------

I really cannot find it everything has led me to a dead end Ive taken the remote apart and the IC seems to be unlisted on the internet

 

[jpanhalt]

Hi Sneitzke38,

I assume this is not some new invention you are trying to make, but rather something fun to learn with. Perhaps also important, I am not an engineer, but simply a hobbyist. So, I tend to look for something simple -- even if old technology -- that works. In all honesty, after I designed and got the circuit in Post #34 to work, I said to myself, this is too complicated. Use a microprocessor. I switched to a PIC 12F508 and never actually incorporated a final version of that 555-based circuit in the device I was building.

Apparently, no one here has experience either with the simple, single-555 jammer that has been referenced (Posts #33, 48, and 55). In fact, FvM has given a good arguement why it may not work with modern systems (Post #9).

I think trying a 555-based solution has merit, and my suggestion was and still is, make a 555 oscillator. Pick a simple, and standard design. The design you pick really doesn't matter that much. The one in the datasheet is fine. You really don't need exactly a 50% duty cycle. The one I suggested is anther example. Paisley (**broken link removed** ) has other designs. Personally, I would stay away from those that couple the output to the timing resistor/capacitor. That is not to say they won't work, but they are less validated in this application and introduce another variable. Pick a validated design and stick with it. Resist the temptation to get pulled in multiple directions by other designs. You will end up going in circles.

First, build an oscillator. Calculate the values you need for the resistors and capacitor for 38-39 KHz carrier. Get it to work. If your values are way off from what you calculated, let's figure out why. Then make another oscillator for the 1 KHz modulation. Now, combine the modulator output at 1 KHz to the reset pin of the carrier modulator. When that is working, add the output transistor and IRED's and see if it blocks the TV remote like you want it to do.

Searching for schematics of IR controls from various manufacturers, such as Samsung, will be fruitless. They are probably microcontroller based. If the engineers used a 555 chip, they were overpaid.

Best regards,

John

 

[sneitzke38]

OK thanks for the response im going to make a reliable Astable Oscillator and then connect to Reset on my existing circuit.

---------- Post added at 03:06 ---------- Previous post was at 01:49 ----------

One oscillator with a steady 1Khz. On to the next one

 

[sneitzke38]

Ok well it is still not working dont know why? Heres what I have so far:

With this circuit im using everything like it is in the schematic.


In the same circuit im using it with a 10k pot instead of a resistor the output from the last circuit is connected to pin 4 of this circuit


And this is how I have the transistor configured

 

[aliraza786]

just change your 555 it may b burnet......

---------- Post added at 07:41 ---------- Previous post was at 07:23 ----------

final solution of your problem try this circuit ...

 

[sneitzke38]

I will try that circuit later today but I just found out my 10k pot is affecting both 555 so I am not getting a 1khz on one of the 555 but it is mirroring the other circuit. I am going to try to put some diodes in here.

Thanks for the schematic!

 

[Raza]

Hi sneitzke38,
How you checked the working of the circuit?
TV REMOTE CONTROL JAMMER Circuit
You said it is not working either, I checked both the circuits and they work without any problem. The set frequency varies between 25.4 KHz to 60.0 KHz. My suggestion if you want to see visually whether it is working or not, replace the LEDs from IR to normal RED ones and replace temporarily 10n capacitor from pin s2+6 to Ground. Power on the circuit and adjust the 10K pot to get a minimum frequency (it will be arround 5.0 Hz) and you will see the clear flicker on the LEDS.
In your case the only possibility I can guess is improper connections of BC557. See the datasheet for identifying the proper Emitter-Collector-Base terminals.
BC557 pdf, BC557 description, BC557 datasheets, BC557 view ::: ALLDATASHEET :::

Any further question is welcomed.
Goo Luck

 

[jpanhalt]

What are you using for your power supply? Do you have decoupling capacitors at each IC and at the power supply? What size capacitors are you using for that? It is common to use 10 uF at the power supply and 0.1 uF ceramic at each chip as close as practical to the power pin and ground.

John

Edit: I just built the oscillator sections of the circuit as shown and described in Post #72 using fixed resistors on a conventional breadboard. Power supply was an Agilent (HP)3630A at 9V. It worked well, and the decoupling capacitors were absolutely essential. I used 0.1 uF ceramics across Pins 8 and 1 of each IC and a 100 uF across the power rails, which probably wasn't needed. When I loaded the output with a 10 mA LED, duty cycle of the 38 KHz increased a little, as expected (See: Paisley, loc.cit.).

 

[sneitzke38]

Thats good news but how do i get the decoupling capacitors in the circuit (where)? I do not know what that term means thanks.

---------- Post added at 03:47 ---------- Previous post was at 03:45 ----------

Is this supposed to make the 10k pot only affect one circuit?

 

[jpanhalt]

Thats good news but how do i get the decoupling capacitors in the circuit (where)? I do not know what that term means thanks.

Here are some recent threads and posts. #2 is a very good post that pretty much sums it up. #4 is a more theoretical thread.

1) https://www.edaboard.com/threads/222856/
2) https://www.edaboard.com/threads/223754/#post953571
3) https://www.edaboard.com/threads/214249/
4) https://www.edaboard.com/threads/212775/

Here is a nice tutorial from Analog Devices: https://www.analog.com/static/imported-files/tutorials/MT-101.pdf

As I said in Post#76, " I used 0.1 uF ceramics across Pins 8 and 1 of each IC and a 100 uF across the power rails, which probably wasn't needed."

John

 

[sneitzke38]

Those are great! Will try them soon. Would a value like 0.01uF be to low? Thats what I'm thinking but just going to check
Thanks for all of that info!!

 

[sneitzke38]

OK never mind that question I just bought a 0.1uF