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Re: crude TV TX

Post by Admin on Sat Jun 23, 2018 4:06 pm

Absolutely no problems, Ivan.
I will see if I have the time to do one myself, but I really must thank you for letting us know about this product.

BR Harry

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Re: crude TV TX

Post by Ivan on Fri Jun 22, 2018 1:55 pm

Hi Harry,
I am sorry, but I have no opportunity to deal with the PA now. It looks exactly as it is depicted on the banggood pages, but I cannot run it and measure its parameters. Probably later (manana Smile ).

VBR from Ivan

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Re: crude TV TX

Post by Admin on Wed Jun 20, 2018 7:43 pm

Hi Ivan,
Thanks for the info. That was quick!
The last stuff I ordered from China took about 5 to 6 weeks.

You must share a pic r 2 and give a short review, if you have got the time.
I would be really interested to read your thoughts and findings about it.
That would be really appreciated by me, and many others, I am sure.

BR Harry

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Re: crude TV TX

Post by Ivan on Tue Jun 19, 2018 7:50 am

Hi,
the PA module just arrived. It is complete with the heatsink (56 mm of course).

BR from Ivan

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Re: crude TV TX

Post by Ivan on Sun Jun 17, 2018 7:00 am

Hi all,
if you do not mind less upper frequency limit, there is another module here. It is even cheaper.
The banggood.com seems to protect buyers quite well: it keeps your payment until you
confirm you got the goods in good condition (maximum for two months if I remember correctly).
If not, you can open a dispute and you have a chance to get another piece or refund your
money.

BR from Ivan

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Re: crude TV TX

Post by Admin on Sat Jun 16, 2018 9:34 pm

I think that there is a lot of stuff coming out of China that does not meet quality standards. I am still a bit upset about the 2000 pieces 78L05 and 78L12 that I bought and not a single one of them worked. It is easy to get fobbed of with factory rejects.

About 4 years ago bought a few 8GB micro-SD cards, and they started to function great, and fast. Then I found out that if you write more than 4GB of data to them it over-writes data: 4GB chips re-formatted and labelled as 8GB.

But I cannot complain on the whole, as I have had a lot of good stuff from China, if one accepts some leeway with the product descriptions.

Ok on your antics in your younger days. I think that most RF and technical guys have such stories to tell. But your was interesting reading :-)

BR Harry

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Re: crude TV TX

Post by Ruud on Sat Jun 16, 2018 7:15 pm

Keep in mind that 'Chinese 3 Watt' probably means 1,5 Watt or even 1 Watt.
But even then, it is a good module for the price!

By the way: in my 'naughty years' I used a Motorola amplifier module for a studio-transmitter link on 882 MHz. for a couple of my friends who were running a pirate radio station. This module had a tremendous gain! 1 mW input was good for 6 Watts output!
You could only use them in class C, but that was no problem since the signal was FM anyway.
(With the encoded MPX signal to the main transmitter.)
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Re: crude TV TX

Post by Admin on Sat Jun 16, 2018 5:47 pm

Hi Ruud,
I may well do just that, use the Spanish address.
Ok on the heat-sink. I have loads of them kicking around.

Since my massage, I found a PCB in the shack. I was too mean to throw it away because it has 2x 10-Watt wideband amplifiers. It was intended for a police repeater system using leaky-feeders in underground railway stations. It has a gain of about 50dB.

I used it once to repeat the VHF FM band inside our house (using Biltema TV coax - leaks like a seive :-)
I had full coverage of the FM band, even in the basement, but I did use a 20dB preamp at the FM Yagi antenna on the roof. But the 3W module does look nice and is very small. I will probably get one anyway for future projects.

BR Harry

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Re: crude TV TX

Post by Ruud on Mon Jun 11, 2018 10:07 am

Size is only 37 x 56 mm. So a relative small heatsink.
(If is unlikely that they really mean 56 CM!)
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Re: crude TV TX

Post by Ivan on Mon Jun 11, 2018 5:38 am

Hi Harry,
use your address in Spain. Parcels priced below EUR 22 (goods plus postage) should be delivered free of tax and duty into the EU. Wait until the price drops a bit (now it is EUR 22,11) or redeem your discount points at banggood.com.
BTW I am unsure whether the heatsink is a part of the kit. But the price would be fair even without the heatsink (includes PCB, SMA connectors etc).

VBR from Ivan

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Re: crude TV TX

Post by Admin on Sun Jun 10, 2018 9:45 pm

Ivan wrote:Hi,
what about making use of a module like this ?

BR from Ivan

Hi Ivan,
Now THAT is a nice module Very Happy  That would certainly do the job :-)

USD 25 seems a bit unbelievable for something like this. It would cost me more to buy just the heatsink locally!

(If I bought from China then the new SWE rules would double the price due to Post office "China surcharge", customs handling, customs duty, etc).

BR Harry - SM0VPO

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Re: crude TV TX

Post by zsolt on Thu Jun 07, 2018 5:49 am

hi , i'm working on it .Should this be in the antenna housing (see picture) or at the modulator housing ? 
PCB or ugly design in a metallic box ?

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Re: crude TV TX

Post by Ivan on Thu Jun 07, 2018 5:36 am

Hi,
what about making use of a module like this ?

BR from Ivan

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Re: crude TV TX

Post by joy444444 on Wed Jun 06, 2018 2:46 pm

Hi, if your transmit frequency is 300-450 MHz then you can build a simple one transistor amplifier with BFG135 transistor. They are available on ebay from China. They should give about 15 dB gain.. 1 mW input should give you 20 mW output .. this should cover your 50 meter range requirements.

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Re: crude TV TX

Post by zsolt on Tue Jun 05, 2018 11:47 am

Admin wrote:Ok, I understand. Whjat sort of distance are you trying to cover?

The output of a normal "commercial" TV-modulator/mixer (from a VCR, video game etc.) is usually in the region of something like 10uW (-20dBm), which will give you a range of just a couple of metres. But if you open the can you will find a resistive attenuator at the output.

The modulator will give an output of about 0dBm (1mW) and the resistive attenuator is to prevent overloading the input to a TV. You can simply bridge the attenuator and run it full power into your amplifier.

The amplifier you may need could be quite a high demand, but if you look at previous posts you will find info for a DC-1GHz 20dB amplifier chip.

A commercial wide-band TV antenna should do the job, if it is designed for the bands you want, and you don't have to do any building :-)

BR Harry - SM0VPO

HI,
the distance is about 30 to 50 m , open field , except the walls of the house. It's about the modulator i built together with the arduino . I  can try with simple V antennas . Do those have ferite core & coil inside ? Can't find them in any shop 
I do have a comercial amplifier .It says that it's for cable tv.
The signals should be strong . The main RF source comes from a modem which has TV output . The audio and video comes from the sat receiver which is also strong signal .
Can i use the antenna below to transmit?

I know it's for receiving since i bought it years ago for that . I just wonder what would happen if i apply the signal from the modulator to it and point it to the house

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Re: crude TV TX

Post by Admin on Mon Jun 04, 2018 4:01 pm

Ok, I understand. Whjat sort of distance are you trying to cover?

The output of a normal "commercial" TV-modulator/mixer (from a VCR, video game etc.) is usually in the region of something like 10uW (-20dBm), which will give you a range of just a couple of metres. But if you open the can you will find a resistive attenuator at the output.

The modulator will give an output of about 0dBm (1mW) and the resistive attenuator is to prevent overloading the input to a TV. You can simply bridge the attenuator and run it full power into your amplifier.

The amplifier you may need could be quite a high demand, but if you look at previous posts you will find info for a DC-1GHz 20dB amplifier chip.

A commercial wide-band TV antenna should do the job, if it is designed for the bands you want, and you don't have to do any building :-)

BR Harry - SM0VPO

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Re: crude TV TX

Post by zsolt on Mon Jun 04, 2018 5:06 am

hi,
I think that only a wide band antenna would work because i have ~120 channels in total . And the programs of interest are in the higher region . I think if i do a manual scan on the tv i can get the frequencies .
Here s an update of my dilema 

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Re: crude TV TX

Post by Admin on Mon Jun 04, 2018 1:52 am

The absolute easiest antenna for local use is to take a bit of coaxial cable, remove the outer insulation, then draw the screen back over the cable.
Here is the concept:

To calculate the length, 150/frequency(MHz) = total length (in metres).
This will give you an omni-directional antenna.

If you want a directional antenna then you can use a TV antenna that is suitable for the frequency you want.

BR Harry

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Re: crude TV TX

Post by zsolt on Sun Jun 03, 2018 5:31 am

Hi,
this is what i have by now 

T think all i need now is antennas . For the tv i can purchase several types of indoor antennas like this https://www.dedeman.ro/cluj-napoca/antena-camera-cu-amplificator-fz-3/p/1018504
What antenna do i need to put at the modulators output ?

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Re: crude TV TX

Post by Admin on Mon Apr 23, 2018 5:21 pm

I have a little experience that may be of interest.

I used to work with FM repeaters, "Talk-Trough" and such things (RF -> AF -> RF). Usually dual frequency simplex.

In one installation I installed an "on-frequency repeater". We had to get the output and input isolated by something like 80dB for short-range comms.
The TX and RX both used directional antennas; the receiver antenna was a very narrow beam Yagi.
The antennas were then installed on either side of a company building (huge building, about 8 floors high).

More recently I worked with RF repeaters that simply amplified the RF from a "donor antenna", mounted outside tunnels, and a leaky feeder inside the tunnel so that GSM, GSM-R, UMTS and WCDMA were re-radiated. Again the isolation has to be good. Before installing the radio, one test is to stuff a CW generator into the donor-antenna and then use an analyser to measure the tunnel antenna. Then you can measure the isolation. For tunnels the isolation has to be really good, better than 110dB, if you intend to amplify a received signal so it can stuff a couple of watts out the other end.

In Lunda, Maj-Lis complained that there was no "Radio Vinyl 107" coverage in the house. So I climbed to the roof and mounted a 107MHz antenna on the roof and measured the signal. I was getting about -80dBm , so I used a 60db amplifier and stuffed the -20dBm into some cheap TV coax in the basement and bottom floor of the house. It worked a treet :-)

Interestingly I have here by my side a pair of 10W wideband VHF amplifiers (to 150MHz) for exactly this purpose. The idea is to fiddle with filters and circulators to build my own bi-directional repeater. But that is a retirement project. Even though I am 66 I stillhave not retired.

In other words, physical distance and directional antennas can give you really good RF separation.

BR Harry


Last edited by Admin on Mon Apr 23, 2018 5:26 pm; edited 1 time in total (Reason for editing : 66 year old brain keeps miss-spoling werdz.)

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Re: crude TV TX

Post by Ivan on Tue Apr 10, 2018 6:02 am

zsolt wrote:
What if i connect a terrestrial antenna  and the signal  from a sat receiver to this . Will this oscillate? 
If all is installed properly, it should not oscillate.

I believe that this way the output would not get back to the input. 
Depends on RF separation (directivity + distance) between the antennas. I expect the path between RF IN and RF OUT is slightly lossy, so it should be OK.

The tv sender is ~ 20km away , interesting is that the signal is present only in certain spots in the yard. 
With the phone is happening the same thing , for example i have good signal exactly in the middle of the street , and in the back yard , but absolutely no signal in the house .
Looks like there is an obstacle between you and the TV/mobile tower. The direct path is blocked an you are inside the scatter interference pattern. BTW, what material is your house from? Steel reinforced concrete is an almost perfect RF shielding...

The wifi would go directly in air  because the manufacturer guaranties high range (it has 2 stick like antennas)
The two antennas are used for better radiation pattern. Yes. it increases the gain in the horizontal plane a bit.

BR from Ivan

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Re: crude TV TX

Post by zsolt on Mon Apr 09, 2018 6:51 pm

Hello ,
to the subject like always  Wink
So this little box is a mixer also.. 
What if i connect a terrestrial antenna  and the signal  from a sat receiver to this . Will this oscillate? 
The antenna is very directional i believe (will make picture) i don't know how it's called also, has no amp in it but i can buy one for it . The output of the modulator would feed a similar directional antenna just that this one points to the house . I believe that this way the output would not get back to the input. 
The tv sender is ~ 20km away , interesting is that the signal is present only in certain spots in the yard. 
With the phone is happening the same thing , for example i have good signal exactly in the middle of the street , and in the back yard , but absolutely no signal in the house .
The setup i would like to have is something like : a pillar in one end of the yard containing parabolic antenna and all that goes with it, tv antenna ,and the wifi modem . From this pillar i would take a 20 ... 25 m  coax for the tv signal , preferably underground , to the first wall of the house . There i would somehow use an antenna to cover about 15 m radius around. In the underground section , beside the coax i would also put the ac 220V supply and an IR repeater for the sat receiver in a plastic tube , here is called copex tube (its used for underground and in wall installations) 
The wifi would go directly in air  because the manufacturer guaranties high range (it has 2 stick like antennas)
I would try all this because i hate to see wires in the house   tongue

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Re: crude TV TX

Post by Ivan on Thu Apr 05, 2018 11:52 am

Hi,
"What does mean CH xx  in tv ? is that a label for certain frequency to avoid using real numbers like "492. 034" ? "
Exactly so. The pairs of carrier frequencies (video and sound) are called "TV channels" and numbered with integers.

"Why does the module have RF in input ?"
It can mix signals from an antenna or cable TV with its own signal. If the RF input is unused, it should be terminated
by a 75 ohm resistor.

"How does a  nonsymmetric antenna  look like ?"
It is e.g. a vertical over a groundplane.

BR from Ivan

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Re: crude TV TX

Post by zsolt on Mon Apr 02, 2018 2:24 pm

Hi,
You can bet it looks ok  Cool

I took the code from the net , and modified it a little for a Joystck and an I2C backpacked LCD
Still have tot test if it works with the tv  lol!
What does mean CH xx  in tv ? is that a label for certain frequency to avoid using real numbers like "492. 034" ? 
Why does the module have RF in input ?
How does a  nonsymmetric antenna  look like ?
For indoor antennas i can find V shape telescopic antennas . Or some classy antennas  that look like some art objects , probably they have a wire inside and amp . Those also have power supply

Oh and here's the code 

/*
 *  this tv modulator program is originally taken from http://www.onetransistor.eu/2018/01/i2c-analog-tv-modulator-arduino-lcd.html
 *  Changes :
 *  JoyStick instead of pushbuttons : URX- A1; URY - A0 ; SW - pin12;
 *  I2C backpack LCD (PCFxxx) (addr: 0x3F)
 *  LCD backlight switches off after ~5 sec. of no Joystick activity
 *  Modulator :  SAMSUNG RMUP74055AD 
 */
#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
#include <EEPROM.h>

LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);  //(addr, en,rw,rs,d4,d5,d6,d7,bl,blpol); // master

#define MOD_ADDRESS (0xCA >> 1)

// 4.5MHz, 5.5MHz, 6MHz, 6.5MHz
const byte mod_sound[4] = { 0x00, 0x08, 0x10, 0x18 };
byte eChannel, eSoundIdx, eOn, eTest;

#define btnRIGHT  0
#define btnUP     1
#define btnDOWN   2
#define btnLEFT   3
#define btnSELECT 4
#define btnNONE   5

unsigned long keyTime = 0;
char cnt=0;

/****** Keypad functions *****/
byte readKeypad() 
{
   
  int URX = analogRead(A0);    // left = 1023 ; liber = 508; right = 0
  int URY = analogRead(A1);    // down =0; liber = 530 ; up=1023

  
 
  if (URY > 600) { cnt=0; lcd.backlight(); return btnUP;}
  if (URY < 400) { cnt=0; lcd.backlight();return btnDOWN;}
  
  if (URX > 600) { cnt=0; lcd.backlight();return btnLEFT;}
  if (URX < 400) { cnt=0; lcd.backlight();return btnRIGHT;}
  
  if (!digitalRead(12)){cnt=0; lcd.backlight(); return btnSELECT;}

  if(cnt<10)cnt++;
  if(cnt==10)lcd.noBacklight(); 
  return btnNONE;
}

void keypadAction() {
  unsigned long currentTime = millis();
  if (currentTime - keyTime < 300) return; // less than 100 ms passed; quit

  byte key = readKeypad();
  keyTime = currentTime; // store last call time

  // perform actions
  if (key == btnNONE) return; // no key is pressed; quit
  switch (key)
  {
    case btnRIGHT:
      {
        if (eChannel < 69) eChannel++;
        EEPROM.update(0, eChannel);

        if (eOn) mod_changeChannel(eChannel, eTest);
        break;
      }
    case btnLEFT:
      {
        if (eChannel > 21) eChannel--;
        EEPROM.update(0, eChannel);

        if (eOn) mod_changeChannel(eChannel, eTest);
        break;
      }
    case btnUP:
      {
        if (eOn) eOn = 0;
        else eOn = 1;
        EEPROM.update(2, eOn);

        if (eOn) {
          mod_start(eChannel, eSoundIdx, eTest);
          lcd.setCursor(0, 0);
          lcd.print("  << ON AIR >>  ");
        }
        else {
          mod_sleep();
          lcd.setCursor(0, 0);
          lcd.print("   << OFF >>    ");
        }
        break;
      }
    case btnDOWN:
      {
        if (eTest) eTest = 0;
        else eTest = 1;

        if (eOn) mod_changeChannel(eChannel, eTest);
        break;
      }
    case btnSELECT:
      {
        eSoundIdx++;
        eSoundIdx &= 3;
        EEPROM.update(1, eSoundIdx);

        if (eOn) mod_setSoundCarrier(eSoundIdx);
        break;
      }
  }
  lcdUpdate(eChannel, eSoundIdx, eTest);

  delay(100);
  mod_getStatus();
}

/***** Modulator functions *****/
void mod_setFreqBytes(byte &fm, byte &fl, byte channel, boolean testMode) {
  if ((channel < 21) || (channel > 69)) channel = 21;

  uint16_t freq = 32 * channel + 1213;
  fm = freq >> 6;
  if (testMode) fm |= 0x40;
  fl = (freq & 0x3F) << 2;
}

void mod_start(byte channel, byte soundIdx, boolean testMode) {
  byte fm, fl;

  mod_setFreqBytes(fm, fl, channel, testMode);

  if (soundIdx > 3) soundIdx = 1;

  Wire.beginTransmission(MOD_ADDRESS);
  Wire.write(0x88);
  Wire.write(0x40 | mod_sound[soundIdx]);
  Wire.write(fm);
  Wire.write(fl);
  Wire.endTransmission();
}

void mod_sleep() {
  Wire.beginTransmission(MOD_ADDRESS);
  Wire.write(0xA8);
  Wire.write(0x20);
  Wire.endTransmission();
}

void mod_changeChannel(byte channel, boolean testMode) {
  byte fm, fl;

  mod_setFreqBytes(fm, fl, channel, testMode);

  Wire.beginTransmission(MOD_ADDRESS);
  Wire.write(fm);
  Wire.write(fl);
  Wire.endTransmission();
}

void mod_setSoundCarrier(byte idx) {
  if (idx > 3) idx = 1;

  Wire.beginTransmission(MOD_ADDRESS);
  Wire.write(0x88);
  Wire.write(0x40 | mod_sound[idx]);
  Wire.endTransmission();
}

void mod_getStatus() {
  if (!eOn) return;
  byte s = 1;
  int c = Wire.requestFrom(MOD_ADDRESS, 1);
  if (c == 1) s = Wire.read();

  if (s & 0x01) {
    lcd.setCursor(0, 0);
    lcd.print("  << ERROR !! >>  ");
  }
}

void lcdUpdate(byte channel, byte soundIdx, boolean testMode) {
  lcd.setCursor(0, 1);
  lcd.print("CH");
  lcd.print(channel);

  lcd.setCursor(6, 1);
  if (testMode) lcd.print("TEST");
  else lcd.print("    ");

  lcd.setCursor(12, 1);
  switch (soundIdx) {
    case 0: lcd.print("4.5M"); break;
    case 1: lcd.print("5.5M"); break;
    case 2: lcd.print("6.0M"); break;
    case 3: lcd.print("6.5M"); break;
  }
}

void setup() {
  //pinMode(10, INPUT); // for LCD shield

  Wire.begin();
  lcd.begin(16,2);
  pinMode(12,INPUT);
  lcd.print("  TV Modulator  ");
  delay(1000);
  lcd.clear();

  // get/set initial EEPROM parameters
  eChannel = EEPROM.read(0);
  if ((eChannel < 21) || (eChannel > 69)) eChannel = 21;
  EEPROM.update(0, eChannel);

  eSoundIdx = EEPROM.read(1);
  if (eSoundIdx > 3) eSoundIdx = 1;
  EEPROM.update(1, eSoundIdx);

  eTest = 0;

  eOn = EEPROM.read(2);
  if (eOn) {
    lcd.setCursor(0, 0);
    lcd.print("  << ON AIR >>  ");

    mod_start(eChannel, eSoundIdx, eTest);
  }
  else {
    lcd.setCursor(0, 0);
    lcd.print("   << OFF >>    ");
  }

  lcdUpdate(eChannel, eSoundIdx, eTest);
}

void loop() {
  delay(500);
  keypadAction();
}

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Re: crude TV TX

Post by Ivan on Mon Apr 02, 2018 9:58 am

Hi, congrats. It looks perfect!

BR from Ivan

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Re: crude TV TX

Post by zsolt on Sun Apr 01, 2018 8:54 am

HI,
been to the flea market  Very Happy   , that's an experience ... anyway i found out that our flea market is very "up to date" . Fortunately i found an old sat receiver with that module 

After a quick search i found that i can connect this to an arduino (http://www.onetransistor.eu/2018/01/i2c-analog-tv-modulator-arduino-lcd.html) and i have same modulator like that from the shop

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Re: crude TV TX

Post by Ivan on Sun Apr 01, 2018 7:44 am

Hi Jalex,
I am fine, thanks.
There is no schematic. I talk generally about the features needed and about ready-made types, see links in the text.

VBR from Ivan

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Re: crude TV TX

Post by Jalex2 on Sat Mar 31, 2018 2:02 pm

Ivan wrote:Hi Zsolt,
this modulator is similar to that I have posted its URI to you. It generates PAL video and mono audio on a selected channel and can add the RF signal to other ones. You can try to connect a 75 ohm nonsymmetric antenna tuned to the selected channel right on the RF OUT connector and check the range. The LCD TV should show something in direct vicinity of the antenna at least.

BR from Ivan
Hi
Ivan How have you been? it's been a while.
I build one of these a long time ago but I had trouble getting the audio 
I was using 4.5 and NTSC  as I am in The USA and never was able to get it tuned.
Where is the schematic  you are talking about here.
Jim

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Re: crude TV TX

Post by Ivan on Thu Mar 29, 2018 6:43 am

Hi Zsolt,
this modulator is similar to that I have posted its URI to you. It generates PAL video and mono audio on a selected channel and can add the RF signal to other ones. You can try to connect a 75 ohm nonsymmetric antenna tuned to the selected channel right on the RF OUT connector and check the range. The LCD TV should show something in direct vicinity of the antenna at least.

BR from Ivan

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Re: crude TV TX

Post by zsolt on Wed Mar 28, 2018 6:21 pm

hi , i will try this soon as i got my hands on one module , I forgot to mention that the tv is a simple lcd tv , now it's getting digital channels  from cable tv provider , browsing through the tv's menu i found that i can make a scan for digital channels and analog channels also . So i believe it could work with a modulator . 
Oh and i found also radio stations , but i believe that those are also digital  because i can't catch them with my pocket radio if i touch it's telescopic antenna to the coax cable (live wire ).

I can also purchase a modulator like this . It has no indication that it could work like aerial transmitter . In description it's said that it can be inserted in the tv providers network ....

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Re: crude TV TX

Post by Ivan on Wed Mar 28, 2018 9:27 am

Hi,
check the modulator using a coaxial cable to the TV. Then I would try connecting a dipole directly to the RF modulator output. If the power is not enough, consider a simple amplifier.

Maybe this is the solution for you.


BR from Ivan

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Re: crude TV TX

Post by zsolt on Wed Mar 28, 2018 8:22 am

hi , i  have seen such a module in 2010, that has an output for coaxial cable . Can i put a tranzistor something to that to make it  send in the air ? 10 m range would make me happy
I will visit the flea market on sunday , maybe i'll find such ting

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Re: crude TV TX

Post by Ivan on Tue Mar 27, 2018 6:04 am

Hi Zsolt,
the video TX is a VSB wideband TX. If you do not spread the RF outside your house, an AM TX should do, too. The video detector in the TV set often is a single diode for B/W. I suppose you will feed the TX with composite full color video in the proper standard (NTSC/PAL/SECAM). Then you need a FM TX for sound, 4,5/5,5/6,5 MHz (depends on the standard of your TV set) apart from the video carrier.
You can grab all this from an old VCR or DVD player with RF output. It usually is a screened module with RF antenna connector. Maybe it will require some amplification and a transmitting antenna.

BR from Ivan

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crude TV TX

Post by zsolt on Mon Mar 26, 2018 9:12 am

Hi ,
does the crude TV tx work in the end ? 
i would like to use that to transmit AV signal from a satellite receiver to a TV, without cables  . The tv still has analog RF input (the classic coax input ) I would use the smallest indoor antenna that i could hide in the back side of the tv . So no wires can be seen (except the 220 v power supply of the tv )

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