I built a fm big from a kit back in 90’s, an organisation called “talking electronics “ magazine released kits monthly, I remember this thing had a range of nearly a kilometre on 2 AA batteries, loved it.
Harika imiş keşke semasi olsa veya anlatsanizda yapardik bobin ve transistör baglantilarini veya entegre mi kullanılmış idi ve kondanstorler en önemlisi de çok iyi icat olurdu su 500 metre bile çok sasirtici olurdu O zamanlarda uzay montaj verici yapardim hem emitere hemde kollektore bobin attigim bir verici yapmistim hazir kitler alıyordum hazir olmayan kitler aliyordum öyle cok hoşuma giderdi
@kumarsizhayat-r7y il y a 2 mois It was great, I wish there was a diagram or you could explain it, we could do the coil and transistor connections or was it integrated and the capacitors, most importantly, it would be a very good invention, even 500 meters would be very surprising At that time, I used to make a space assembly transmitter, I made a transmitter where I put coils on both the emitter and the collector, I was buying ready-made kits, I was buying kits that were not ready-made, I liked it that much. @kumarsizhayat-r7y. il y a 2 mois There are still open circuits there, I am thinking of trying it soon but I will try it in a very distant time, thank you very much for your suggestion. _translation by_ 🐾 _Montréal 🇨🇦_
In the US, these are legal with 100mw or less power and 1 meter or less antenna. They are very popular in AM for people to use their restored antique radios to play old music or drama.
Brings back memories of me and my mate's when we where about 11 building a Hartley Oscillator and Transmitting am with it, we also found we could do Morse code on it and that increased the range to about 10 Times...Great fun using bits from old broken Transistor radio's.
UK 🇬🇧 broadcast frequencies are 87.5 - 108MHz my friend. Japan if I remember correctly, is 73 - 92MHz 🤔 Too many years developing prototype car radio. It's frazzled my brain 😂
Interesting video to use as spy device use around 110 mhz off fm band and receive on cheap scanner build into something maybe mains power with short covert range bigger the item longer the aerial with in reason no need for batts
Hello. I 've also bought several pcb modules of this kind but the compensator screw goes out and then moreover I don't have optimal listening performance. Annoying burns during 'listening. I have decided to buy a F-908 but have not been able to use it yet since I am not interested in applying headphones but instead a 'speaker so that I can record via smartphones, digital recorders, etc. But I am just now getting a 3.5 to 2.5 adapter for the jack. That's all for now.
What a nice young fella me lad you are. Bought 2 of these and 2 cheap transistor radios. Idea is that I'm fed up with pushing buttons on a walkie talkie and hopefully the old dragon and I can argue about who's going to have a headache tonight whilst I mess about outside and she's cutting her toenails with my new wire cutters. Do you think 9V would be better and what length aerial would be best ? Just finished a quad bench power supply 2 x 9A 0V - 38V linear (can be paired to give 18 A), 1 X LT1083's 8A?(4 off in parallel) linear and a big buck. Weighs a ton. Why? no idea but it's fun init.
The transmitter should run on a 9 volt battery without issue. I found (on my other bug video) that a 1-1.5 meter antenna wire gave me about 200 feet range.
CBOT wrote me on your channel but I don't see it (I only got the email notification. here is his message : "The spy ones usually operate on lower frequencies so they can't be picked up by a typical radio channels. I think you can go on Amazon and find them." My response : Okay, but I can't place them anywhere (since I can't get into other people's houses and don't have someone who can...) and I have to look for some solution, maybe a directional microphone with a dish and a trivial class D amplifier would be enough. I can hear by "naked" ear and I can hear my neighbors plotting against each other and sometimes I can understand some dialogue. Could you advise me on how to build a properly made wall microphone ....? I just don't want to dwell too much on this topic. Thank you very much. Hi.
Hi. I personally do not know how to make a conductive microphone but i did review a product which can hear through thin walls. See here. th-cam.com/video/58-HIUDDnoY/w-d-xo.html
Hey bro! Thnx for a cool chanal. Mayby it will work with the radio on the smart phone, there is it possible to tune in on any station. See you. Mic from Denmark.
I wanted to ask if it is possible to detect the fm frequency of a nearby bug? I live in a two-family house and I am afraid that my neighbors use one pcb of these for ex. in the living room and the fm radio in another room ... . I intuit that they are talking about me (in the distance, very low volume ...) but unless I have tangible evidence to record I can't nail them!!! Clearly this is an environmental version (it detects voices, noises from a particular room, office, etc.) I hope to be able to detect the empty frequency (I choose an empty freq., move the pcb closer to the small radio, adjust the variable pF and then I want to test all the empty freqs) to see if I get what I have in mind. For the time being thank you very much.
Hi Fred! Thank you for this interesting video report. Could you please advise the specs for a proper antenna (kind of wire, its length, etc...) to be coupled to this device? Many thanks in advance. Have a great day.
Hi it will depend what freq you tune the transmitter. There proper antenna length calculators on line. As a rough guide it will need to be as long as a standard FM radio
Could you please give me a hint at how not to have the batteries draining in the Tecsun, even without it working, just by the virtue of them sitting in it??!
What frequency did you tune it to? Can you measure it? My variable pf broke and I would like to replace it with a fixed value. Let me know. Thank you very much.
You can replace the trimmer capacitor with any small value capacitor. Start at 47p for lower frequencies somewhere at 85 to 90 MHz. Use an even smaller value capacitor for higher desired frequency.
@fredintheshed1 how could I build an FM transmitter with an older 1999 KOSS radio with its old parts please help me I live in Texas and am really interested in building my own FM transmitter I can't seem to find anyone to help me maybe you can please :)
Why would you look like a wally with a radio in hand? people stare at their phones all day long walking down the street...dont mind what others think man !
These cheap transmitters have not got the power. I guess you could try and mod a powerful PMR 446 radio like the Beofeng UV5R. That would give you the range.
I built a fm big from a kit back in 90’s, an organisation called “talking electronics “ magazine released kits monthly, I remember this thing had a range of nearly a kilometre on 2 AA batteries, loved it.
Harika imiş keşke semasi olsa veya anlatsanizda yapardik bobin ve transistör baglantilarini veya entegre mi kullanılmış idi ve kondanstorler en önemlisi de çok iyi icat olurdu su 500 metre bile çok sasirtici olurdu
O zamanlarda uzay montaj verici yapardim hem emitere hemde kollektore bobin attigim bir verici yapmistim hazir kitler alıyordum hazir olmayan kitler aliyordum öyle cok hoşuma giderdi
Orasi hala açık devreler var denemeyi düşünüyorum yakin ama cok uzak bir zamanda deneyecegim önerin icin cok tankyou
@kumarsizhayat-r7y il y a 2 mois
It was great, I wish there was a diagram or you could explain it, we could do the coil and transistor connections or was it integrated and the capacitors, most importantly, it would be a very good invention, even 500 meters would be very surprising
At that time, I used to make a space assembly transmitter, I made a transmitter where I put coils on both the emitter and the collector, I was buying ready-made kits, I was buying kits that were not ready-made, I liked it that much.
@kumarsizhayat-r7y. il y a 2 mois
There are still open circuits there, I am thinking of trying it soon but I will try it in a very distant time, thank you very much for your suggestion.
_translation by_
🐾 _Montréal 🇨🇦_
In the US, these are legal with 100mw or less power and 1 meter or less antenna. They are very popular in AM for people to use their restored antique radios to play old music or drama.
That makes sense on the AM radios. Cheers
why would it be illegal other wise? i dont know the laws?
Brings back memories of me and my mate's when we where about 11 building a Hartley Oscillator and Transmitting am with it, we also found we could do Morse code on it and that increased the range to about 10 Times...Great fun using bits from old broken Transistor radio's.
Sounds like you had some fun Steve
How did using Morse code increase the range ?
I think the FM broadcast band doesn't start until 88 MHz, that's why you couldn't hear any other stations around there
UK 🇬🇧 broadcast frequencies are 87.5 - 108MHz my friend.
Japan if I remember correctly, is 73 - 92MHz 🤔
Too many years developing prototype car radio. It's frazzled my brain 😂
Well fred what a great spy kit me and my next door neighbour talk to each other with our listing device p.s I've just ordered a camera pen
I have a different one, from Amazon. Mine was also tuned for ~96Mhz out of the box. Using them for a spy workshop.
can you post a link please
Can we use it to hear the phone calls in nearby mobiles.
Interesting video to use as spy device use around 110 mhz off fm band and receive on cheap scanner build into something maybe mains power with short covert range bigger the item longer the aerial with in reason no need for batts
Hello. I 've also bought several pcb modules of this kind but the compensator screw goes out and then moreover I don't have optimal listening performance. Annoying burns during 'listening. I have decided to buy a F-908 but have not been able to use it yet since I am not interested in applying headphones but instead a 'speaker so that I can record via smartphones, digital recorders, etc. But I am just now getting a 3.5 to 2.5 adapter for the jack. That's all for now.
Hmm nice one seems the range is comparable with those low power legal FM transmitter devices
Yes i recon about the same but smaller footprint. Ive got another to try when i get the time.
There's no filtering on these things. I tried one, and it's just pumping out harmonics all over the place.
That's what you get for dodgy illegal stuff from China ;)
@@digitalmediafan It's not illegal. lol
The tecsun tried to Feel Collins at one point 😛🤪 Nice review vid👍👍👍
Just waiting for him to ask the dog - ‘What’s the frequency Kenneth?’
"is your Benzedrine, uh-huh"
lol, you could have taken the radio in the car! Liked and subbed :)
What a nice young fella me lad you are. Bought 2 of these and 2 cheap transistor radios. Idea is that I'm fed up with pushing buttons on a walkie talkie and hopefully the old dragon and I can argue about who's going to have a headache tonight whilst I mess about outside and she's cutting her toenails with my new wire cutters. Do you think 9V would be better and what length aerial would be best ? Just finished a quad bench power supply 2 x 9A 0V - 38V linear (can be paired to give 18 A), 1 X LT1083's 8A?(4 off in parallel) linear and a big buck. Weighs a ton. Why? no idea but it's fun init.
The transmitter should run on a 9 volt battery without issue. I found (on my other bug video) that a 1-1.5 meter antenna wire gave me about 200 feet range.
I like the way you pause for a second to enjoy the D&B on the radio, old skool raver by any chance? :)
LOL no idea what station it was. Could have been a pirate.
CBOT wrote me on your channel but I don't see it (I only got the email notification. here is his message : "The spy ones usually operate on lower frequencies so they can't be picked up by a typical radio channels. I think you can go on Amazon and find them." My response : Okay, but I can't place them anywhere (since I can't get into other people's houses and don't have someone who can...) and I have to look for some solution, maybe a directional microphone with a dish and a trivial class D amplifier would be enough. I can hear by "naked" ear and I can hear my neighbors plotting against each other and sometimes I can understand some dialogue. Could you advise me on how to build a properly made wall microphone ....? I just don't want to dwell too much on this topic. Thank you very much. Hi.
Hi. I personally do not know how to make a conductive microphone but i did review a product which can hear through thin walls. See here. th-cam.com/video/58-HIUDDnoY/w-d-xo.html
LOL "for a bit of a crack" those of us in the US:
Uh... wut?
LOL. means "a bit of a laugh" :-)
You could build it into a USB charger.
Yes 5 volts would work.
Hey bro! Thnx for a cool chanal. Mayby it will work with the radio on the smart phone, there is it possible to tune in on any station. See you. Mic from Denmark.
I wanted to ask if it is possible to detect the fm frequency of a nearby bug? I live in a two-family house and I am afraid that my neighbors use one pcb of these for ex. in the living room and the fm radio in another room ... . I intuit that they are talking about me (in the distance, very low volume ...) but unless I have tangible evidence to record I can't nail them!!! Clearly this is an environmental version (it detects voices, noises from a particular room, office, etc.) I hope to be able to detect the empty frequency (I choose an empty freq., move the pcb closer to the small radio, adjust the variable pF and then I want to test all the empty freqs) to see if I get what I have in mind. For the time being thank you very much.
Best bet to find a FM bug's freq would be a used hand radio scanner which also covered the broadcast band that would pick up any FM radio signal.
@@CB-RADIO-UK Which radio scanner do you recommend? Thank you very much.
Test it with 9v and a calculated antenna 😉
If you turn the little pot right, does that mean you need to tune closer to 108 or 88?
I think it went high towards 108
Thanks!
Hi Fred! Thank you for this interesting video report. Could you please advise the specs for a proper antenna (kind of wire, its length, etc...) to be coupled to this device? Many thanks in advance. Have a great day.
Hi it will depend what freq you tune the transmitter. There proper antenna length calculators on line. As a rough guide it will need to be as long as a standard FM radio
Thanks!
I couldn't help myself lol. Link works :)
Good to hear they are still active :-)
@@CB-RADIO-UK While I'm on Fred, the reciever you use, is it okay for picking up morse frequencies and/or HAM radio? Cheers in advance?
Yes it covers the HAM band and has SSB. It wont cover 11 meters though.
@@CB-RADIO-UK Thanks Fred.
Could you please give me a hint at how not to have the batteries draining in the Tecsun, even without it working, just by the virtue of them sitting in it??!
My batteries last for over a month on stanby. Not really sure why yours would drain ?
What frequency did you tune it to? Can you measure it? My variable pf broke and I would like to replace it with a fixed value. Let me know. Thank you very much.
Mine would tune to just outside the broadcast band on FM. As for replacing the tuning cap with a fixed crystal ive no idea.
Very interesting mate, ordered a load!
Ive bought another design to play with. :-)
bro can you help me?
I have the same module, but the trimpot is broken. is there another way to replace that component?
You can replace the trimmer capacitor with any small value capacitor. Start at 47p for lower frequencies somewhere at 85 to 90 MHz. Use an even smaller value capacitor for higher desired frequency.
Hi what wire do you use for the antenna
Just some plain single core wire
fred approved :)
Can you do one of them bluetooth ones?
how do u adjust the transmitter broadcasting frequency?
If you look on the board there is the tiny white screw pot next to the microphone.
Hi how near doe's the pick up mike need to be to the sound, could it hear your voice if you were other end of your living room say 6 meters away.
Its quite sensitive. If someone was speaking loud at 6 meters i think the mic would pick it up.
In the uk, what bandwidth is it legal to use this on?
I am not sure this transmitter is legal at all.
🤣
@fredintheshed1
how could I build an FM transmitter with an older 1999 KOSS radio with its old parts please help me I live in Texas and am really interested in building my own FM transmitter I can't seem to find anyone to help me maybe you can please :)
Not sure how to build one with the older parts. Iam sure there would be a a project somewhere out on the web which could be adapted.
How long does it last on a 9v battery non stop?
I did not run my battery totally down but i did 90 mins testing and it was still going.
Why would you look like a wally with a radio in hand? people stare at their phones all day long walking down the street...dont mind what others think man !
Yeah thats true
If I want,you can Send to Indonesia
how is the real test meters
?
Depends how long you can make the wire antenna.
need one for longer distance like 1 to 3 miles. How?
These cheap transmitters have not got the power. I guess you could try and mod a powerful PMR 446 radio like the Beofeng UV5R. That would give you the range.
can it pick up conversations?
Yes if spoken in a normal voice. the mic is very sensitive.
HOW STABLE IS THE FREQUENCY? DOES IT HAVE AFC
Freq seemed ok. Quite wideband. Doubt it had AFC
@@CB-RADIO-UK I had the very cheap one transistor version and its useless.just harmonics all over the place.
@@esecallum Think the quality varies. This one was not as good as the first. th-cam.com/video/30ylAskcO1k/w-d-xo.html
YOU BRITS ARE SOOOOOOOOOOOOOOOOOOOOOO FUNNY
How much
Will it work with 9v battery
Yes it should do.
@@CB-RADIO-UK great thanks for your quick reply :)
How long would those batteries last on this setup?
Mine went a good couple of hours making the video without issue. . Prob twice that if left on maybe longer. .
I from Indonesia Jakarta
69TH COMMENT
How much
Sorry bud cannot help.