[Transistor]

i have two questions to ask you

1,  Your transmitter`s  oscillator and rf amp works on 2.5 volts?

2,  what is the output of LM2931A on 2.5 volts?

thanks

[Good radio]

which brand contain sensitive and good selectivity receiver?
from above

[Good radio]

Hi,
today i went to market, for buying a good FM radio.

but i found many radios, thay have also old japnese brands.
like National, Panasonic, Sony, Aiwa, Victor, sanyo

i didnt understand which brand to buy.

plz help

thanks

[Transistor]

sorry i forgot to mention that

I m using this preamp with your transmitter
http://www.uoguelph.ca/~antoon/circ/preamp.htm

and your transmitter is worked when my battery voltage goes down to 2.5 volts

It means its oscillator which is connected with voltage regulator IC, and rf amp transistor which is connected directly, will also work on 2.5 volts ?

[Transistor]

Hi Audioguru

I m using ur FM transmitter you said it will not work on less then 5 volts.

it also worked on 2.5volts? why?

I m using transistor shaped voltage regulator IC like yours.

[Transistor]

i didnt found  NTE123AP transistor in my city.
what transistor i will use in the place of this transistor.

thanks

[FM frequency]

I Want to change my FM radio frequency 109-120 MHZ.
because i want to tune my FM transmitter in between 109-120 MHZ.
this is my question from first to last.

[FM frequency]

http://www.gatago.com/rec/radio/swap/23839865.html

[FM frequency]

i have four turns of coil in my radio receiver.
by removing one turn it will happen?

[FM frequency]

I want to tune FM transmitter on that frequency.
i think by adjusting coil or variable cap we move FM radio frequency for some MHZ.

[FM frequency]

Plz Reply

[FM frequency]

HI all
I want to change my FM radio frequency 109-120 MHZ,
will it happen by changing the coil or variable capacitor?

and i also want to change my other FM radio frequency to air band 118-136 MHZ
what can i do?

thanks in advance:)

[Audioguru FM Tx]

hi AN920 and Audioguru :)
hi AN920 i like your circuit :)
thanks :)
but still i have a question....
it will drift its frequency, can i use Audioguru`s circuit in the place of
your 100mW circuit.

and also i m thinking about using good RF transistors in the place of 2N3904.
i think it will do the job.
both of you plz think and any body who is reading this, and tell me about good transistors for using in the place of 2N3904.
thanks..

[Audioguru FM Tx]

i found many high power transmitter on net but they are all drift fequency or very big circuits (a lot of parts and coils), high voltage and very complicated.
i want small & stable circuit like yours but incease power like 500mW or 1W.
thanks.
plz think about mod-5 ;)

[Audioguru FM Tx]

The 2N3904 is a general purpose audio transitor, therefore its gain at 100MHz is a max of only about 3. A real RF transistor would have much more gain, give a much higher output power, require an emitter resistor to limit the power and require a heatsink.

you know any transistor which i use in the place of 2N3904 which will increse the power?

[Audioguru FM Tx]

Hi Audioguru
i want to use your FM Mod-4 on 11 Volts.
will it incease the output power to 500mW?

thanks:)

[Audioguru FM Tx]

Link

http://www.ajpotts.fsnet.co.uk/Circuits.html

[Audioguru FM Tx]

250mW is probably its input power, not its output power.

input power??
this is written on its web
"This Narrow Band FM VHF transmitter will output approximately 250mW of RF power using a 2N2222 and can operate between 75 and 146MHz"

[Audioguru FM Tx]

circuit

[Audioguru FM Tx]

Hi Sir Audioguru
what do you think about this transmitter it is good transmitter or not.
its out put is written on its web is 250mW is it right?
thanks in advance.

[AJP's Transmitter]

here is the circuit diagram

[AJP's Transmitter]

circuit diagram

[AJP's Transmitter]

Hi All,
I want to built this transmitter, plz give your suggestions about this transmitter.
http://www.ajpotts.fsnet.co.uk/Circuits.html

[Audioguru FM Tx]

Also lowering the value of the 47k to around 33k it is possible to get up to 20mW while still keeping harmonics low. That is a 100% increase in RF power with much lower noise and harmonics as the original circuit.

20mW or 250mW?

[audioguru fm transmitter]

The RF cops use their van with a directional antenna on top and their receivers to find the transmitter causing the interference

this is the only(directional antenna) technique, or other military or other secret sevices use different  techniques and equipments?