ФМ предавателче

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This
FM transmitter attaches in series to one of your phone lines. When
there is a signal on the line (that is, when you pick up the handset)
the circuit will transmit the conversation. In particular it will
radiate from the phone line itself. It is a passive device - there is
no battery. It uses the signal on the phone line for power. No aerial
is needed - it feeds back the RF signal into the phone line which
radiates it in the FM band. The frequency of transmission may be
adjusted by the trimcap. L1 is 6 turns of enamelled wire, L2 is 8 turns
and L3 is 6 turns. Spread out L3 coil about 1 mm apart. The coils
should not touch. a solder connection (or tap) is required from the top
of the first turn in the L3 coil to the pad next to the coil. Solder a
piece of wire to the top of the first turn as shown on the overlay.
Then solder the other end to the pad immediately next to the L3 coil.
R1 & C4 act as a low pass filter. C3 is a high frequency shunt. L2
is a RFC (radio frequency shunt.) It decouples the power and audio from
the transmitter amplifier circuit. L1 and C6 should be adjusted to
match a frequency on your FM receiver. With C1 at 27p you will find
that the kit tunes into the FM band in the 86 - 95 MHz area. With C1 at
22p the band is raised to about 90-95mhz (depending in the coil
spacing.) If you want to move this tunable area still higher to over
100MHz range then replace C1 by a 15pF or 10pF capacitor. You can
experiment to get greater transmission range away from the phone line
by adding an aerial (about 150 cm of 26 gauge wire) to the collector of
T2.

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The
important part of the circuit is formed of the Colpitts type
oscillator. C3,C4,C5,C6,CD1-CD2 and L1 determines the frequency. BF982
and dual gate MOSFET are active parts in oscillator. When the input
impedance of the MOSFET gate inputs are high, LC tank is not affected.
However transistors force the LC tank and cause phase shift. Two driver
stages are added to isolate the antenna from oscillator. First stage
(BF199) ampifies the low signal of the oscillator and works as a
constant load. The second stage (BFR90) amplifies the signal going
through the antenna some more. A short copper wire can be used as an
antenna here. Attaching a large antenna to this circuit is unnecessary
because the output power is low. Notes: 1. Coil 1: Winding wire must be
1 mm thick and isolated. Number of turns: 3.5 . 5mm core must be used
and the distance between each turn must be 1mm. 2. You can use BF199
instead of BFR90. 3. If you can't find the varicap diode, you can use
MV104 instead.

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This
RF Amplifier is used for boosting small fm transmiters and bugs. It use
two Philips 2N4427 and its power is about 1Watt. At the output you can
drive any linear with BGY133 or BLY87 and so on. Its power supply has
to give 500mA current at 12 Volts. More voltage can boost the distance
but the transistors will be burned much earlier than usual.! In any
case do not exceed the 15Volts. The Amp offers 15 dB in the area of
80Mhz to 110 Mhz. L4, L5, and L6 are 5mm diameter air coils, 8 turns,
with wire 1mm wire diameter.An easy project, with great results.

MiniRDS
Encoder





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It's not important if you use this RDS
encoder with one transistor FM bug or 1 kW transmitter. It will give your station all
common RDS features: Program service name, dynamic PS, Radiotext, Program Type
identification, Traffic Program, Traffic Announcement and Music/Speech flags, Alternative
Frequencies list and some more. This unit is ideal for mounting into a small transmitter.
Modern concept is based on new [You must be registered and logged in to see this link.] chip which processes and
stores the data and generates output signal. Analogue part is very simple due to fully
digital generated RDS signal.

Features

• Small dimensions
  
• Very low power consumption
  
• Operates stand-alone
  
• Unlimited reprogramming
  
• Wide control possibilities
  
• EEPROM memory for data storage during power-off
  
• Broadcast quality output signal
  
• Continuous RDS transmission during all operations
  
• 4 modes for dynamic/scrolling PS incl. word alignment
  and one-by-one character scrolling
  

RDS services directly supported

[You must be registered and logged in to see this image.]PS (Program Service), PI (Program
Identification), PTY (Program Type), TP (Traffic
Program), TA (Traffic Announcement), DI (Decoder
Identification), M/S (Music/speech), AF (Alternative
Frequencies), RT (Radiotext), User Defined
Groups.
(The RDS services are described in Support)

[You must be registered and logged in to see this link.] For more information download the MRDS192
datasheet.

Technical specifications

Dimensions:	4.2 x 2.7 cm
Supply voltage:	7-25 V
Supply current:	9 mA
Output RDS signal voltage:	adjustable 0-1.2 V p-p
RDS signal bandwidth:	+/- 2.4 kHz (43 dB)
Output impedance:	<400 Ohm (DC-100 kHz)
Communication interface:	synchronous, IIC

The unit layout

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Supply - Power supply connector
1: + 7-25 V
2: ground
Check the right polarity before connecting the power supply!!!

Out - RDS output
1: output
2: ground

LPT - PC port interface
1: SDA (serial data)
2: SCL (serial clock)
3: ground

Level - Output RDS signal level
adjust

How to connect the unit to a PC computer?

For control purposes, the unit can be connected
either to LPT or COM port of the PC, each in unidirectional or bidirectional mode. The
control software supports all these connections.
In unidirectional mode you will not be able to read any data from the unit back to
the PC and you will not be able to detect if the data were sent successfully, but the
cable is easier to make. In standard situations any of the following diagrams will work.

• MiniRDS to LPT port connection cable
  (unidirectional):
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  The 680R resistor may be replaced by a diode as
  in following case.
  Direct connection between pins SDA and 6 is not recommended.
  
• MiniRDS to LPT port connection cable
  (bidirectional):
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• MiniRDS to COM port connection cable
  (unidirectional):
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• MiniRDS to COM port connection cable
  (bidirectional):
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  The R9 resistor on the board should be 2k or
  less in this case (default value is 4k7).
  

Some important notes:

• The communication interface meets the IIC serial
  synchronous bus standard with the clock rate limited to 600 Hz. So the unit can be also
  controlled from almost any microcontroller.
  
• The PC control software emulates the IIC bus on a LPT
  (parallel) or COM (serial) port.
  
• You must be logged under administrator laws in
  Windows to access parallel port. Serial port can be accessed in all cases.
  
• Some low cost USB-to-COM adapters don't handle all
  port pins required by the unit. You may use Port Access TEST built in the control
  application to check it.
  
• In some cases bidirectional COM connection may not
  work if non-standard port is used (USB adapter, laptop PC) - use any other connection.
  
• The RDS unit must be powered when sending any data.
  
• We do not supply any cables or adapters with this
  unit.
  

As you can see, cable soldering and some basic
electronics knowledges are required. If you prefer complete plug-and-go solution rather,
look at the [You must be registered and logged in to see this link.].

Control software for Windows

Download: [You must be registered and logged in to see this link.]
(420 kB)

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How to connect the unit to a transmitter?

Answer to this question depends on the transmitter
you use:

Mono transmitter with audio or MPX input
connector (may used with stereo encoder plugged to this input)
Audio/MPX and RDS signal must be mixed together and pluged to the transmitter
input. There exist many ways to do this. You may use simple schematics provided below. The
resistor values are chosen approximately, but these values might be right.

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Mono or stereo transmitter with RDS input
connector
It's the simplest situation. Connect the encoder to this input.

Stereo transmitter with audio left and audio
right connectors and no more inputs
An encroachment to the transmitter is necassary here. Find a varicap (capacitive
diode) in oscillator and connect the RDS input connector by the following diagram. Then
fix the connector in front panel of the transmitter.

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(C) 1999-2008 Pira CZ.
All rights reserved.

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Kijk hoe het niet moet: Teveel ruimte tussen de windingen van de spoeltjes, en lijm gebruikt.

Aan de slag


Hierboven
zie je m'n eerste poging tot FM bug. Ik heb zorgvuldig het schema
bekeken, en alles aan elkaar geknoopt. Gelukkig is het schema niet zo
ingewikkeld, dus kon ik alles heel klein houden. Bij HF schakelingen
moet je de draadeinden zo kort mogelijk houden om zo min mogelijk
storingen te krijgen en dat is zoals je hierboven ziet goed gelukt... [You must be registered and logged in to see this image.]
Het schema voor een eenvoudige FM bug
Boodschappenlijstje

• 3 x 4.7 KOhm
  
• 1 x 100 KOhm
  
• 1 x 10 KOhm
  
• 1 x 270 Ohm
  
• 2 x 10 uF
  
• 1 x 1 nF
  
• 1 x 5.6 pF
  
• 1 x 2-18 pF trimmer (groen)
  
• 2 x luchtspoeltje 5 wikkelingen op 4 mm diameter
  
• 2 x BC 547 Transistor
  
• 1 x condensator microfoontje
  

Doet het niet


Helaas,
hoe ik ook aan de instelcap draaide, ik hoorde geen plop of stilte op
de radio zoals ik dat zou mogen verwachten. Dus maar eens langs gegaan
bij circuits online en de diverse forums erop nagelezen. Wat blijkt, ik
had heel die instelcap verkeerd aangesloten! Bovendien had ik de
spoeltjes niet zorgvuldig genoeg gewikkeld en die lijm die ik gebruikt
heb zou wel eens voor een load in de spoeltjes kunnen zorgen... Dus een nieuwe poging ondernomen en de instelcap losgemaakt
en opnieuw gesoldeerd, nu met de juiste aansluitingen. Bovendien had ik
nu echt gelakt 0.8mm koperdraad gebruikt om de luchtspoeltjes te
wikkelen. Maar helaas, er was nog steeds niks op de FM band te horen.
Zou ik dan toch de cap met het solderen naar z'n grootje geholpen
hebben? Tweede poging: Protobord


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Dit
is al veel beter. Versterker (links rondom beide elco's en transistor)
keurig gescheiden van HF trap (rechts rondom de instelcap en
spoeltjes), en goed gewikkelde spoeltjes van gelakt koperdraad, zonder
lijm.

Nieuwe poging


Na nog meer gelezen te
hebben over HF schakelingen besloot ik om het schema eens zorgvuldig op
een protobordje te maken. Op een bordje met eilandjes (geen baantjes,
want die pikken signaal op) plaatste ik alle componeneten zo veel
mogelijk het schema volgend. Bovendien gebruik ik voor het instellen
van de trimmer geen (metalen) schroevendraaiertje meer maar een stukje
printbord dat ik wat dunner heb geslepen. Hierdoor voorkom ik dat de
capaciteit veranderd doordat ik met een metalen schroevendraaier
contact maak met de trimmer. Hij doet het (een beetje)


Het resultaat is er
ook naar, want bij het draaien aan de cap hoor ik inderdaad een plots
hevig gekraak op de FM band. En met het instellen van de cap bepaal ik
ook nog eens waar precies tussen de 88 en de 108 MHz het gekraak
hoorbaar is. Wel verloopt de frequentie nogal sterk als ik met m'n hand
in de richting van de bug beweeg. Maar goed, het doet het dus. Alleen
hoor ik nog steeds geen geluiden die opgepikt worden door het
microfoontje. Ik vermoed dat de versterkertrap nogal sterk overstuurt.
Dus begeef ik me opnieuw op de diverse forums om eens uit te zoeken hoe
ik het ingangssignaal moet bewerken... Misschien moet ik de versterking verlagen door R2 te
verlagen van 100k naar bv 47k of 22k. Of zal ik gewoon een potmetertje
nemen? Derde poging, nieuw schema


Op de site van [You must be registered and logged in to see this link.]
kwam ik een iets andere schakeling tegen. Omdat mijn eerdere twee
pogingen niet het succes hadden dat ik ervan had verwacht besloot ik
verder te zoeken... ...wordt vervolgd...

HIGH POWER FM MIC
by Harry Lythall - SM0VPO



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My FM Wireless Microphone has been a very popular project with
beginners and experienced constructors alike. It has been used
inside guitars and as the basis of a remote control system. I
do however, receive many requests for a higher powered circuit
and better microphone sensitivity. Now I can introduce the new
FM Wireless Microphone (v5), which also has a better frequency
stability, over 1Km range (under ideal conditions) and is good
on microphone sensitivity. This has been achieved by adding an
RF amplifier buffer (with 10dB gain) and an AF preamplifier to
boost the modulation a little.


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Construction is quite simple. L1 is 3.25 turns in spiral form
and is an integral part of the PCB foil pattern. The two BC547
transistors can be replaced with (almost) any small-signal NPN
transistor, such as the 2N2222. The final stage is a BC557 PNP
general purpose device. If you use different devices then you
should select the 1M0 resistor for 5-volts DC at the collector
of the the first transistor. Select the 47K resistor for 3 - 4
volts on the collector of the third transistor. Here is the V5
component overlay drawing. Note that there is a modification:


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There used to be a 1n0 5mm cap for supply decoupling, but after
a cange of component supplier (manufacturer?) there developed
some form of RF instability when the gain of the PA transistor
was a little above normal. Replacing the 1n0 to an electrolytic
capacitor of 22uf cured this problem totally. Any "radial" (the
leads both come out of the same end) type electrolytic capacitor
from 0.47uf upwards cures the problem. The finished unit draws
about 30mA which should vary as you touch the tuned circuit, a
good test that the unit is oscillating. You should remove the
4K7 resistor if you use a dynamic microphone.


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The PCB is 50mm x 25mm, a little larger than the first version
but there are three stages instead of just the one. The first
prototype is shown above, beside the battery powering it. The
output power is about +10dBm which is about 10dB more than the
first FM Wireless Microphone. This would theoretically give it
3.12 times the range (1.6Km) but I have only tested it using a
handheld receiver with the TX laying on the bench indoors. But
I got a comfortable 700 meters (and a few funny looks from our
neighbours).


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Above you can see the addition of a "gimmick" capacitor added
across the 12p tuning capacitor to lower the frequency of the
transmitter. Make the capacitor by twisting two lengths of
single core insulated hook-up wire, about 2cm long. This will
reduce the frequency to the bottom end of the band. Cut short
the capacitor to increase the frequency to the desired final
frequency. If you cut it a few KHz too high then just twist
the gimmick a little tighter.


The PCB foil pattern and layout will be placed in the download
section of my homepages. Have fun and please be aware that the
higher power of this project may render it ILLEGAL in your own
country. I can accept no responsibility and it is up to you to
check that you may legally use it. I will accept NO complaints
from any country/state correctional facility.


Very best regards from Harry Lythall


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батка ти си најдобар до сега еден куп мини предајници стави за симињање јавно те пофалувам продолжи така ако можеш дај најди ми некој плл шема комплетна со делови кои можат да се најдат и да не е по можност со епром.поздрав само продолжи така.

A дали овие ФМ буби реално би работеле? Оти се што се врти на
интернет не е проверено.

половината се со машни за филинг малку да се изнервираш ама ако си умешен у сето тоа само што ја гледаш шемата пред себе ке знаеш отприлика каде може да е грешката и дали е исправна шемата.

последните две мислам дека на последната и фали блок кондензатор променлив на самиот калем на 6 нано хенри а на другиот има машна на калемот паралелно со калемот има блок 12 пико што ако баш фреквенцијата се поклопи со некоја радио дифузна станица ни ти ке се слушаш ни тоа ке се слуша таму треба да се стави променлив кондензатор а за другите тек ке ги разгледам

Према тебе кои шеми се ОК ?

последните две се малку повеке шљапави со машни другите мислам дека се ок

50MHz-Fan напиша:
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А оваа добра е?

да работи супер само е слаба ја има во емитер и е под ознака ADR01 има 200метри домет на 12волти

Kade e oscilatorot, modulatorot i koj del ja dava taa snaga?

модулаторот е мокрофонот а осцилаторот е составен од BD138 транзисторот,c1,c2,c3,c4,R1кој ја одредува струјата натечење на емитерот на транзисторот, разделникот на напон R2 и R3 кои ја одредувааат работната точкана транзисторот калемите L1 И L2 снагаташто ја дава е само осцилаторот ама таасила е многу мала.

sakam da napravam pll ama kristal nemam kaj mozam da go najdam za veronikata 6,4megaherci ako nekoj znae neka pise ili ako go ima neka kaze jas sakam da kupam

batka od kade ja najde slikava ja slikase li ili ja simna odlicna e

браво димце, 3 поста един след друг

Гарант е симната од нетот

daj nekoj ako ima plocka od veronikata 2 ili 4wpllpro neka ja stavi na forumov da ja simnam sakam da ja pravam.

kaj ste luge ajde da napraime edno zvere od 10vati na am predavatel

како можам и јас да закачам некоја шема комплетна слика со склопен модул и шема со комплетна плочка се заедно?