The video sender you show here looks very familiar to the "UT66" series. Basically these transmitters (the one´s that I´ve tested) work on half frequency. So if you´d transmitt for example on 500MHz the oscillator wil runn at about 250Mhz. The frequency gets doubled in the first transistor stage - and - via the filters (L+C) the intended frequency is picked out. I´ve tested lots of these video transmitters (other brand) and they all have the same problem - the antenna is missmatched. If you pull out the telescopic antenna to it´s full length, the range usually isn´t that good and often I also had it that the 1/2 Frequency from the "intended" frequency is also broadcasted (weakened but still strong). It helps to use some kind of communications receiver, take off the antenna from the receiver (BNC or SMA) and put it on "W-FM" on the video transmitter´s Frequency (usually these drift so use W-FM). Then place the receiver in some distance untill you hear static, and align the antenna (length) on the transmitter for best performance. UT66 usually I pull in the telescopic antenna and just put out the "thinnest" part (the upper one) a little bit... maybe 1 inch out from the "big antenna" and I get a strong resonance on the intended frequency (on other video transmitters I´ve tested the perfect resonance spot varies). With the antenne "in resonance" the range increases dramatically (still no big range) and the harmonics / unwanted signals are quite well supressed. The output power of such a device is in the range of 10...15mW ... if it were 100mW you´d get more range. The UT66 series (optically very similar to the UT66) is very simple designed. The final amp is just modulated in the emitter (the 1k potentiometer for video level). It has FM problems (which the TV ignores) and some units have problems with the linearity (probably a final amp bias issue) meaning if there´s to much white in the picture the picture goes nuts / distors and other problems. I´ve tested a few brands (via ebay) and the best unit is the one from "reflect" called "Reflect RF280" - it also uses an oscillator at the 1/2 frequency but with the antenna proper aligned, the output is quite clear. It´s stronger than the UT66 and has a good picture / audio. Sad that they don´t allow these ... still... I mean in Germany - after my knowledge - they weren´t ever allowed (still people used them as it seems) You´re... were... really ahead there in your great country :) Circuits of these transmitters can be found using google picture search but basically you can even built a dirt-cheap 2 transistor video transmitter (colpitts oscillator in the TV band. Feed in the 4,5MHz signal on base and feed in the video on emitter). Did that... it... works but it´s really "dirty". Hope I could bring some light into this topic, I´ve really spent a lot of time with these. The range varies very much on the environment. With the transmitter in the house it´s about 100 feet as it was said, but if there´s nothing between the transmitter and the receiver it´s more like 300 feet before the picture starts to get bad. More range can be archeived with a different transmitter modell.
My neighbour had one of those way back in the early 90s, he liked playing tricks on some of the older Neighbors who still had analog TV, we lived in a rural community in Ontario Canada we had cable readily available but a lot of the older people had analog still.
I do have a BT modulator. Channel 12 MTS stereo. Has a +60 dB output and yes connected to an antenna it goes about as far as this thing. I use it in my home analog cable distribution and have it playing music videos off a hard drive 24/7. Have many, as in hundreds of concert performances that I just let play in random and listen to more than watch. That's why the stereo modulator.
I recently discovered that you can run an rf signal through a signal booster and achieve the same goal. I found this out while I was looking for a signal sender that doesn't require me to have a bunch of clunky crap connected to the receiving TV just so that I can use it and had a very difficult time for whatever reason. With the amp you just need to supply power to the booster at the transmitting end. You can also get the same result using a VCR
Very interesting video. I didn't know that you should run TVs occassionally to keep them working well. I have about 8 vintage 12" black and white sets that have not been turned on for about a year or so. How often should I dig them out and operate them? Also have a 20" Zenith that I'm in the process of repairing but not sure on how to disconnect the picture tube. i will make a video of the TV soon so you can see what I'm referring to.
I have one called a 'TV Genie' but the picture looks scrambled. There are 4 trim pots inside in addition to the 2 audio and video gain adjustment pots along with 7 caps. Anything I could adjust or replace to fix the picture?
Looks pretty simple, I wonder if there is a schematic kicking around... not much use to me though I don't have any TV's with a tuner anymore. I would be a fun project though for someone that works on TVs. I wonder if _bandersontv_ has one (VHF type that is). Cheers,
Speaking of the Transmitter, when I look around at the yard sale, I scored the iPod FM Transmitter for a dollar where I can play the music right through the USB, auxiliary, or iPod to play a music, plus I can transmit on 87.5 MHz to 107.9 MHz on stereo, and I can't believe that someone really don't want them anymore where they want nothing to do with that because, they don't have an iPod or auxiliary jack to connect to the transmitter while play the music at the same time. So I went ahead and buy the transmitter from the owner and take home with me. What's funny how I can get the audio from 87.7 MHz on FM, I get a blank picture with an audio right where I receive on Ch. 6, and it's really weird that how did it work.
I still like the novelty of small tv sets :-). I have never heard of curtis ones but there were plenty of other manufacturers making T.v Senders. (as they were called at the time). A few oscillators being modulated and mixed together, not much but very very handy :-D. I've always loved minimal circuits that perform amazingly well.
I have 2 of those Curtis mono units I've used over the years but recently found a stereo video sender with no brand name, it's about the same size as the older ones and works great. Have you seen the stereo model?
I had one of those 2.4 GHZ video transmitters made by a company called Terk. But the power supply units for one of the units died. But it was 2.4 GHZ Analog and the video was frequency modulated instead of amplitude modulated. It used to get interference though from nearby wireless routers in the neighborhood and would also cause inteference to them. If it was set to the right (or should I say "wrong") channel I would completely lose my wireless internet. Because of the 2.4 GHZ microwave frequency. Which is what wireless routers also operate on.
The Wavecom jr and sr was the same. The difference was the sr version had an IR return channel. We used to use them for ham TV use because the 2.4 band is shared with amateur radio. They were FM video 20MHz deviation and would do a wonderful job on 2.4 cordless phones and wireless routers. When we operated it caused hell for the neighbors wifi. I could never hit the repeater from my house, so I used to pack up my gear and drive up the hill and set up remote with my camera, transmitter on 2.4 with a high gain antenna, and a 1.2ghz receiver to receive the signal back from the repeater. There would typically be 4 of us on the air at once. We had a quad screen, so we could see all 4 input frequencies at once. Would go on the air for hours, either just talking to each other, or showing live pictures or play tapes we made. Every time I set up I would get the a couple people pay me a visit on the hill because their internet got really slow or their phones cut out wondering what was up. I would say, too bad so sad, I was operating in a legal, licensed band. A few even called the industry Canada folks that informed them that their devices were not protected from interference as they operated on the ISM or industrial, scientific and medical band as a secondary use, and ham radio was a primary user for us to experiment on. The "scientific" portion. It pissed them off but there was nothing they could do. I would say to them, hey I am only here for a few hours, be glad one of your neighbours isn't a ham, because he could operate all day and there is nothing you could do. I think a few thought I was doing it to annoy them but in fact it was the only location I could get a clear shot to the repeater from my location as I was about 50KM away and that is a long way to shoot a 1 watt microwave signal. Those days are long gone though. All the guys that I used to do ATV work with are all 6 feet under now. Many died of cancer. Can't help thinking it was probably all those microwaves they played with over the years as many of them tinkered with transmitters and antennas and really big power for years, and 2.4GHz is not good to be around.
@@RadioSpectrumDXer1217 That's right ISM, Industrial, scientific and medical band. Home cordless phones and wifi is secondary users. Amateurs on 2.4 can run up to 200 watts I belive. I only operated with 1 wayy into a 33db gain parabolic reflector. That would give the ERP in the focal point of the beam of 2048 watts. Yup that was cooking. Speaking of cooking, on a field dat we set up the transmitter, and pointed the antenna into a glass of water, and it eventually brought the water up to a boil. Don't stand in front of that antenna when it is on. One of the guys in our group that was always playing with 2.4GHz and didn't bother much with safety, walking in front of antennas when transmitter was on ect wasn't feeling well. Finially went to a doctor and got the bad news that he was full of cancer. Likely brought on by years of smoking like a chimney and his excessive exposure to microwaves.
@@12voltvids iv'e had my bluetooth earbuds in listening to music. They will play just fine until the second i turn my microwave oven on to heat up my food to eat, then they start breaking up. But the second the microwave stops they start playing fine again. especially if im closer to the microwave than my phone. Microwave oven is just a "glorified" version of what you were doing. Just shoot the microwave beam into a cooking chamber, add a timer to the transmitter and there you now have an oven. I remember back when I was a kid before fiber optics became a thing (due to its greater bandwidth), before cell towers really dotted the landscape, you would see these microwave relay towers with the parabolic reflectors but they also had these funny looking horns that were shaped like a wedge of pizza or pie wedge. Used for relaying long distance telephone and network (ABC, NBC, CBS) television programing across the country to their local affiliate stations. Many were owned by AT&T A.K.A "ma bell". So obviously this was even before the days of satellites. I know many radio, tv stations though still use microwave relay to remotely send programming from their studios say in one part of town to their transmitter site located in another part of town or even totally different area.
@@RadioSpectrumDXer1217 Microwave ovens operate on 2.45 ghz, which is the top end of the 2.4 wifi band. Bluetooth shares the same frequencies. Once upon a time the phone companies used microwave to link distant communities. Now most is backhauked by fiber, but Roger's still uses microwave links for their cell sites. Many radio stations here used uhf STL but that was a backup because the transmitters had audio delivered by isdn or t1 phone lines as the primary link and the radio link was a backup.
I bought this in a store many years ago in Canada. I am a ham also. Just wondering if this can be tuned or modded to the 430 MHz range to be used in the ham band?
I got a UT-66 which seems to be almost identical to this one. It's allegedly operating at channel 31 but the one I got, has a "homemade" label next to the unmarked hole above the sound control hole, here it says CH-29. I can't find anything on either tho but if I seek with the device I'm trying to play back the channel on, I can sometimes get a quite crappy signal. If I tune the video knob, I can take it from no signal to a very shitty signal. How do I bring it back to the default channel?
i have CASIO SY-20, color it's look like that Sony but the problem on it, the picture not clear and i can't see only some moving out of the range , what problem is going on that?
I had a wavecom jr unit on 2.4ghz FM video and audio modulation. Still have it modified for amateur tv. Mine is programmable from 2.36 to 2.45 GHz and puts out 1 watt. Into a parabolic reflector antenna the distance I have transmitted is point to point 50 km.
The one from Canada, the transvid? Did you find it? I am in Canada and have an old one put away somewhere. I could broadcast to neighbours 5-6 houses away, easily with clear picture and audio. Do you know if these will work with modern tv’s? I would like to see your Canadian brand one.
couldn't you hook up the output from a converter box or modulator to an amp to get a similar effect? we still have channel 28 within range so that's cool.
@@Raptor50aus how much was it Need one for a low power setup for my party to beam a signal to a CRT projector that has the red, green and blue lights. That projector has an rf UHF/VHF tuner in it like the ones in regular old TVs.
I have a similar modulator, think it's a Radio Shack, UHF on Ch35 approx 534Mhz from vague memory. I have a large box with three crystal locked VHF modulators on Ch 0 (46.25Mhz), 5a(136Mhz) and ch 11 (225Mhz). I recently got a 2 channel UHF unit has the Ring Grip name (Ring Grip is an Australian manufacturer of electrical fittings). It can be set to any channel in the UHF band.
I have 3 wacom agile units that can go from a-7 to a-1 covers 2 -83 VHF /UHF and 14-22 CATV, 23 to 135 CATV including the channels in the FM band 95 - 99. I use VHF channels for distribution on my home system. Channel 4 stereo Channel 5, 7, 9, and 12 in stereo, and CATV 17. I dont use any UHF because I receive the OTA digital signals with an antenna and mix that in with my analog channels, so TVs throughout the house can get SD material I insert on the analog channels and HDTV. The analog modulators are used for things like my media players, security cameras ect.
Plenty of signals for your TVs then. Correction: the 2 channel modulator has Clipsal (another Aussie electrical supplier) on the case. I did have a look inside it and noticed the board accommodates up to four modulator modules. It’s actually made by Zytec despite the name on the case
quick question I was considering creating a small diy transmitter for personal use but I'm having trouble finding licensing and legality information, would you be able to point me in the direction of resources on this? Thanks!
Well you don't need a license if the power is low. How low depends on where you are. It is based on field strength a certain distance from the radiator (antenna) which varies depending on your country. There was a pirate that operated for years and years. Probably 20 years and payed nothing but music on the low end of the band. Then one day a high power station was set up on the same frequency and I cont hear it any longer but it was there for many many years.
5 лет назад+1
How do the 'authorities' really 'crack down' on transmitting video or audio ? What's the myth vs reality..did they really drive around in a Van in the early 80s to target 'pirate' video broadcasts? That would be so pathetic.
There was a local pirate that was broadcasting on FM out here pretty much non stop for over 20 years that just one day went off the air. Actually there were 2 or 3 for awhile but they were shut down by industry Canada. I have tapes of one of them, that I have shown on 6he channel.
Nice design. Nowadays they would throw some connectors and a chip on a board and shove it in a cheap plastic case and sell it and it would fail in a week. At least this you can fix. Any ICs on the other side?
Big deal. We aren't talking about LCD TVs. Making a 1.6" LCD is nothing. LCD is very simple technology. Have had them on watches for years. This is a 3 gun 1.5" color picture tube and that is a very complex device when it gets that small. Big picture tubes were easier to make. Small ones not so easy because you have to cram all the same elements into a very small space in the jug, suck out all the air and apply some very high voltages. The tolerances are in the microns. Oh and they are built by hand too. LCD you take a piece of glass put a photo resist on it , put a film mask over it, hit it with UV light to expose the photo resist, devoloped it and wash the glass with acid to create your conductor paths. Apply the transparent electrodes, fuse the glass pieces and stuck on drive electronics on the flexible boards around the edges. A couple of polarizing filters and color for filter over the pixels and a light source. Done. A machine stamps out hundreds of them an hour.
I remember getting portable crt tv in 1999 and broke it and late 2003 had vintage 80s crt portable tv from sisters friend crt was on its way out finally in 2005 crt died and also had red clock radio portable tv combo but bad power cord fried everything
The ones that operated on 900mhz, 2.4 and 5.0 GHz and came with a receiver that hooked to the tv were fine. VCR rabbit, waveform jr (and Sr) and a few others were fine. It was just the ones that operated on uhf tv channel 15 that they stopped selling after a few years. I got that info from a store that was selling them off cheap. Said they couldn't get any more because they banned them due to possible interference with broadcast stations and all future ones would be on a different band.
@@12voltvids These things were always illegal here in the UK, but that didn't stop people getting hold of them of course :) Very useful devices indeed. As for that offset-angle CRT tube, Sinclair Research (yeah the same company that made the ZX series computers) made a small TV over here that used the same technology back in the day. It was called the TV80 (also known as the FTV1). was released in 1983 and was a commercial failure, mainly because it was monochrome and at that time, Sharp had already started developing small colour LCD panels. A cool and fascinating device though, and not too expensive on ebay compared to many tech products of that era
@@countzero1136 The sinclair device used a similar technology. They were using an electrostatic deflection tube, and Sony used a magnetic deflection tube which found itself in wide spread use in door intercom systems. I see them in homes all the time. At the front door a camera and speaker, and in the house a 4" flat CRT monitor. Of course now they are all LCD, but back in the 80s and 90s and as recent as early 2000s companies such as enterphone, used these Sony tubes in their intercom systems because they were flat and could be built into a wall mountable unit. There are still thousands of them out there in service.
Hi, I watch your great channel for quite a long time, thanks for share all the procedures. Would you let me know where can I find (or DIY) this TV transmitter? Is that there still having existing product? Thanks.
You will have to check second hand stores, Facebook marketplace, eBay ect. I haven't seen them in over 30 years for sale. If you can find a made in Canada "transvid" grab it. They were fantastic and had a relatively long range. I had one once upon a time but have no idea where it is. Will probably find it some day when i am not looking for it and that will be happy times.
Did you know that with you modulator setup and a 15 dollar (American) antenna booster and a antenna you can have a lot of analog tv channels of your own making
Well they would transmit but not go more than a few feet. I have a 100 watt transmitter set to 434.6 and 439.25 MHz in the ham radio 70cm band. This translates to channel 59 and 60 on the CATV band. With that i could get a few miles to a buddy's place with directional antennas on each side. Am tv signals take a fair bit of power to go any distance.
@@GaryTheRCcar No analog tv here was vesiduial side band. Look that up for an explanation. Think of it as AM but the lower sigeband only went to something like 600khz and the upper on ntsc went to about 4.2 or 3mhz. The color was transmitter as a bandwidth limited double sideband carrier using 2 suppressed carriers at 3.579545 MHz. This frequency was chosen as it is at an odd harmonic. The sound was an fm carrier centered 4.5 MHz above the video and had its own dedicated transmitter. The output was multiplexed at the antenna. The limit on lower sideband was so it wouldn't interfere with the audio of the next channel down. It was a very complex system, far more than pal because the broadcasters had to satisfy the FCC by producing a system that was compatable with the millions of already installed monochrome system. Europe just said fux b/w we will simucast for a few years snd then shut down b/w transmitters. So they had the ability to use more bandwidth which resulted in a better picture with a much simpler system. Now FM video is used in analog as well for microwave links and satellite transmission where having a channel bandwidth or 30 or 40mhz no big deal and it looked fantastic. These little VCR senders uses 2.4ghz FM. Lots of ham radio tv guys including me modified them to run in the ham bands.
Analog TV was transmitted by amplitude modulation. Actually vestigial side band, so a broadcast transmitter would have additionally filtering, but it is still AM, just with the lower sideband reduced. To make an AM signal you generate a carrier (1 transistor oscillator) Mix in the modulating signal, in this case the video. 1 transistor will do that too. Generate a second carrier at 4.5MHz and input the audio signal to a varactor diode in the oscilator. This will create an FM signal, which is mixed with the carrier and video mixed signal. (1 more transistor) and then a final output amplifier (1 transistor) so 4 transistors is all that is needed. Really quite simple. Add a few more amplifier stages for more power.
Well this little transmitter transmits on uhf channel 15 which is fine if none of the local channels are broadcasting on 15. All my TV's still have analog capable tuners.
The transmitter is not generating color or demodulating color. All it is doing is taking the incoming video signal, which would already have the color encoded on it and AM modulating it onto a UHF carrier and then amplifying it slightly and sending it to an antenna. Its a very simple process.
@@MikinessAnalog A modulator is no different. It takes an existing VBCS (video, blanking, chroma, sync) composite video signal and modulates it on a carrier. Most modulators will have a crystal for the carrier generation so they remain stable. This one doe not, so it has a tendency to drift, but the AFC on the TV takes care of that.
@@12voltvids As i understand it from university, the higher the frequency the less power needed to go the same distance, so I'm assuming being UHF it is probably in the 200mW range? I made a 1 watt FM radio transmitter when I was 19 (77.3 Mhz FM with a 19Khz pilot tone crystal for stereo) and it traveled about 3km.
The tv band here now ends at channel 59. Frequencies starting at 60 is now in the cellular band and with all the antennas the cell companies have it wouldn't take long to find someone jamming their frequencies.
Cause I have a show that I really like and it only ever gets posted on RUclips or other social media platforms for example, like a a Instagram Facebook no I think they only have announcements on Facebook. I have to get permission from them first. If they don’t respond I’ll try and email the people that make the show.
Look on eBay they do come up once in awhile. I'm hanging onto mi e obviously because just like my am stereo and FM stereo transmitters use them to play with my old radios and TV's.
Oh fuck yeh mine need a repair mine PAL I think 😄 Needs a fresh build... Can use sky slx link through aerial ....maybe could boost signal from it Mine got 2 shields inside containing few components But looks similar
@@12voltvids Okay, I don't see any contact info on your RUclips or donation pages. If anyone can point me in the right direction I would appreciate it!
There is just something cool about crt. I love the x-y scope I just got for my vector clock board. My main tv is a 63 plasma I have been enjoying now for 10 years.
Can someone help me understand because I'm new to this, why does everyone say this is illegal? This information is available from the FCC directly. My understanding is that as long as you're under 3 KW of power and your antenna is less than 200 ft then you're completely legal.
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The video sender you show here looks very familiar to the "UT66" series. Basically these transmitters (the one´s that I´ve tested) work on half frequency. So if you´d transmitt for example on 500MHz the oscillator wil runn at about 250Mhz. The frequency gets doubled in the first transistor stage - and - via the filters (L+C) the intended frequency is picked out. I´ve tested lots of these video transmitters (other brand) and they all have the same problem - the antenna is missmatched. If you pull out the telescopic antenna to it´s full length, the range usually isn´t that good and often I also had it that the 1/2 Frequency from the "intended" frequency is also broadcasted (weakened but still strong). It helps to use some kind of communications receiver, take off the antenna from the receiver (BNC or SMA) and put it on "W-FM" on the video transmitter´s Frequency (usually these drift so use W-FM). Then place the receiver in some distance untill you hear static, and align the antenna (length) on the transmitter for best performance. UT66 usually I pull in the telescopic antenna and just put out the "thinnest" part (the upper one) a little bit... maybe 1 inch out from the "big antenna" and I get a strong resonance on the intended frequency (on other video transmitters I´ve tested the perfect resonance spot varies). With the antenne "in resonance" the range increases dramatically (still no big range) and the harmonics / unwanted signals are quite well supressed.
The output power of such a device is in the range of 10...15mW ... if it were 100mW you´d get more range. The UT66 series (optically very similar to the UT66) is very simple designed. The final amp is just modulated in the emitter (the 1k potentiometer for video level). It has FM problems (which the TV ignores) and some units have problems with the linearity (probably a final amp bias issue) meaning if there´s to much white in the picture the picture goes nuts / distors and other problems.
I´ve tested a few brands (via ebay) and the best unit is the one from "reflect" called "Reflect RF280" - it also uses an oscillator at the 1/2 frequency but with the antenna proper aligned, the output is quite clear. It´s stronger than the UT66 and has a good picture / audio.
Sad that they don´t allow these ... still... I mean in Germany - after my knowledge - they weren´t ever allowed (still people used them as it seems) You´re... were... really ahead there in your great country :)
Circuits of these transmitters can be found using google picture search but basically you can even built a dirt-cheap 2 transistor video transmitter (colpitts oscillator in the TV band. Feed in the 4,5MHz signal on base and feed in the video on emitter). Did that... it... works but it´s really "dirty".
Hope I could bring some light into this topic, I´ve really spent a lot of time with these.
The range varies very much on the environment. With the transmitter in the house it´s about 100 feet as it was said, but if there´s nothing between the transmitter and the receiver it´s more like 300 feet before the picture starts to get bad. More range can be archeived with a different transmitter modell.
My neighbour had one of those way back in the early 90s, he liked playing tricks on some of the older Neighbors who still had analog TV, we lived in a rural community in Ontario Canada we had cable readily available but a lot of the older people had analog still.
the others had digital tv in the early 90s? ;)
@@prebenjaeger I didn’t say anything about digital TV, I said some people had cable while others still had analogue over the air.
I have an unbranded one of these. I used to wonder if it was ever legal in the first place. Thanks for the video!
Yes they fall under part 95, yes they are.
Got just the same videdo sender. A Blonder Tongue Agile Mod is what you need for decent signal indoors! Thanks Dave.
I do have a BT modulator. Channel 12 MTS stereo. Has a +60 dB output and yes connected to an antenna it goes about as far as this thing. I use it in my home analog cable distribution and have it playing music videos off a hard drive 24/7. Have many, as in hundreds of concert performances that I just let play in random and listen to more than watch. That's why the stereo modulator.
I cleared out a bunch of my old tvs along with my uhf transmitter years ago, when I was moving.. and I'm still kicking myself for getting rid of it.
Yes old tvs are collector items now. I have a nice Toshiba with a VHS and dvd player built in.
I recently discovered that you can run an rf signal through a signal booster and achieve the same goal.
I found this out while I was looking for a signal sender that doesn't require me to have a bunch of clunky crap connected to the receiving TV just so that I can use it and had a very difficult time for whatever reason.
With the amp you just need to supply power to the booster at the transmitting end.
You can also get the same result using a VCR
Most consumer signal boosters don't provide much signal but a commercial modulator with a 60db amplifier will certainly transmit a few feet.
Also works in Japanese pocket TVs (Casio NTSC-J) on UHF channel 14.
Very interesting video. I didn't know that you should run TVs occassionally to keep them working well. I have about 8 vintage 12" black and white sets that have not been turned on for about a year or so. How often should I dig them out and operate them? Also have a 20" Zenith that I'm in the process of repairing but not sure on how to disconnect the picture tube. i will make a video of the TV soon so you can see what I'm referring to.
I have one called a 'TV Genie' but the picture looks scrambled. There are 4 trim pots inside in addition to the 2 audio and video gain adjustment pots along with 7 caps. Anything I could adjust or replace to fix the picture?
Looks pretty simple, I wonder if there is a schematic kicking around... not much use to me though I don't have any TV's with a tuner anymore. I would be a fun project though for someone that works on TVs. I wonder if _bandersontv_ has one (VHF type that is).
Cheers,
Speaking of the Transmitter, when I look around at the yard sale, I scored the iPod FM Transmitter for a dollar where I can play the music right through the USB, auxiliary, or iPod to play a music, plus I can transmit on 87.5 MHz to 107.9 MHz on stereo, and I can't believe that someone really don't want them anymore where they want nothing to do with that because, they don't have an iPod or auxiliary jack to connect to the transmitter while play the music at the same time. So I went ahead and buy the transmitter from the owner and take home with me.
What's funny how I can get the audio from 87.7 MHz on FM, I get a blank picture with an audio right where I receive on Ch. 6, and it's really weird that how did it work.
The Gemini VCR Rabbit was a popular 2.4 GHz sender/receiver system in the 90's.
I still like the novelty of small tv sets :-).
I have never heard of curtis ones but there were plenty of other manufacturers making T.v Senders. (as they were called at the time).
A few oscillators being modulated and mixed together, not much but very very handy :-D.
I've always loved minimal circuits that perform amazingly well.
Most were am, a few FM. The fn models looked better and went further but required an fm tuner at the other end.
That must have been the reason most people used the AM senders, cheaper.
Fm would require a more expensive device.
@@zx8401ztv well it required a seperate receiver whereas the am senders you just turned your tv to channel 15
Any way to boost the power on this unit.
I am running my analog TV’s with the digital converter, however would like to have one of these
I have 2 of those Curtis mono units I've used over the years but recently found a stereo video sender with no brand name, it's about the same size as the older ones and works great. Have you seen the stereo model?
No, wish I had one. I have 2 stereo modulators.
I had one of those 2.4 GHZ video transmitters made by a company called Terk. But the power supply units for one of the units died. But it was 2.4 GHZ Analog and the video was frequency modulated instead of amplitude modulated. It used to get interference though from nearby wireless routers in the neighborhood and would also cause inteference to them. If it was set to the right (or should I say "wrong") channel I would completely lose my wireless internet. Because of the 2.4 GHZ microwave frequency. Which is what wireless routers also operate on.
The Wavecom jr and sr was the same. The difference was the sr version had an IR return channel.
We used to use them for ham TV use because the 2.4 band is shared with amateur radio.
They were FM video 20MHz deviation and would do a wonderful job on 2.4 cordless phones and wireless routers. When we operated it caused hell for the neighbors wifi. I could never hit the repeater from my house, so I used to pack up my gear and drive up the hill and set up remote with my camera, transmitter on 2.4 with a high gain antenna, and a 1.2ghz receiver to receive the signal back from the repeater. There would typically be 4 of us on the air at once. We had a quad screen, so we could see all 4 input frequencies at once. Would go on the air for hours, either just talking to each other, or showing live pictures or play tapes we made. Every time I set up I would get the a couple people pay me a visit on the hill because their internet got really slow or their phones cut out wondering what was up. I would say, too bad so sad, I was operating in a legal, licensed band. A few even called the industry Canada folks that informed them that their devices were not protected from interference as they operated on the ISM or industrial, scientific and medical band as a secondary use, and ham radio was a primary user for us to experiment on. The "scientific" portion. It pissed them off but there was nothing they could do. I would say to them, hey I am only here for a few hours, be glad one of your neighbours isn't a ham, because he could operate all day and there is nothing you could do. I think a few thought I was doing it to annoy them but in fact it was the only location I could get a clear shot to the repeater from my location as I was about 50KM away and that is a long way to shoot a 1 watt microwave signal. Those days are long gone though. All the guys that I used to do ATV work with are all 6 feet under now. Many died of cancer. Can't help thinking it was probably all those microwaves they played with over the years as many of them tinkered with transmitters and antennas and really big power for years, and 2.4GHz is not good to be around.
@@12voltvids even here in u.s f.c.c rules part 15 says that this device must accept ANY interference that may cause undesired operation.
@@RadioSpectrumDXer1217 That's right ISM, Industrial, scientific and medical band. Home cordless phones and wifi is secondary users. Amateurs on 2.4 can run up to 200 watts I belive. I only operated with 1 wayy into a 33db gain parabolic reflector. That would give the ERP in the focal point of the beam of 2048 watts. Yup that was cooking.
Speaking of cooking, on a field dat we set up the transmitter, and pointed the antenna into a glass of water, and it eventually brought the water up to a boil. Don't stand in front of that antenna when it is on. One of the guys in our group that was always playing with 2.4GHz and didn't bother much with safety, walking in front of antennas when transmitter was on ect wasn't feeling well. Finially went to a doctor and got the bad news that he was full of cancer. Likely brought on by years of smoking like a chimney and his excessive exposure to microwaves.
@@12voltvids iv'e had my bluetooth earbuds in listening to music. They will play just fine until the second i turn my microwave oven on to heat up my food to eat, then they start breaking up. But the second the microwave stops they start playing fine again. especially if im closer to the microwave than my phone. Microwave oven is just a "glorified" version of what you were doing. Just shoot the microwave beam into a cooking chamber, add a timer to the transmitter and there you now have an oven. I remember back when I was a kid before fiber optics became a thing (due to its greater bandwidth), before cell towers really dotted the landscape, you would see these microwave relay towers with the parabolic reflectors but they also had these funny looking horns that were shaped like a wedge of pizza or pie wedge. Used for relaying long distance telephone and network (ABC, NBC, CBS) television programing across the country to their local affiliate stations. Many were owned by AT&T A.K.A "ma bell". So obviously this was even before the days of satellites. I know many radio, tv stations though still use microwave relay to remotely send programming from their studios say in one part of town to their transmitter site located in another part of town or even totally different area.
@@RadioSpectrumDXer1217
Microwave ovens operate on 2.45 ghz, which is the top end of the 2.4 wifi band. Bluetooth shares the same frequencies.
Once upon a time the phone companies used microwave to link distant communities. Now most is backhauked by fiber, but Roger's still uses microwave links for their cell sites. Many radio stations here used uhf STL but that was a backup because the transmitters had audio delivered by isdn or t1 phone lines as the primary link and the radio link was a backup.
I bought this in a store many years ago in Canada. I am a ham also. Just wondering if this can be tuned or modded to the 430 MHz range to be used in the ham band?
Another title that deserves a immediate like even before the video is watched!
I got a UT-66 which seems to be almost identical to this one. It's allegedly operating at channel 31 but the one I got, has a "homemade" label next to the unmarked hole above the sound control hole, here it says CH-29. I can't find anything on either tho but if I seek with the device I'm trying to play back the channel on, I can sometimes get a quite crappy signal. If I tune the video knob, I can take it from no signal to a very shitty signal. How do I bring it back to the default channel?
i have CASIO SY-20, color it's look like that Sony but the problem on it, the picture not clear and i can't see only some moving out of the range , what problem is going on that?
I have a curtis video sender. But, for some reason i can’t seem to get a good enough picture from it.
Very cool. Do you know of anything like this that does VHF?
Get your hands on an old wavecom commercial modulator. They can tune any frequency.
Wonder if they are similar to the Rabbit Boxes they used to sell to extend video through the house via wireless. Never had one, so I can't say.
I had a wavecom jr unit on 2.4ghz FM video and audio modulation. Still have it modified for amateur tv. Mine is programmable from 2.36 to 2.45 GHz and puts out 1 watt. Into a parabolic reflector antenna the distance I have transmitted is point to point 50 km.
The one from Canada, the transvid? Did you find it? I am in Canada and have an old one put away somewhere. I could broadcast to neighbours 5-6 houses away, easily with clear picture and audio. Do you know if these will work with modern tv’s?
I would like to see your Canadian brand one.
No, it's around somewhere but i haven't found it or have been looking for it.
Put the TV on to analog
You can get the TV to scan for analog channels
couldn't you hook up the output from a converter box or modulator to an amp to get a similar effect? we still have channel 28 within range so that's cool.
Yes. You would need a fairly high gain amp. Of course hook this to an amp and get a few miles range.
I hope you use the meter in the frequency measurement of integrators to know the method of measurement and thank you from the heart
I picked one up on Ebay from China that has a digital display and I simply key in the video and audio freq for VHF and UHF and supports NTSC and PAL.
Which one did you buy? Can I get a link to it, please?
@@daMoMenTum www.hllyradio.com/low-power-tv-transmitter-c-2/hlly-05w-tvx50m-tv-transmitter-av-transmitter-vhf-uhf-black-p-31.html
@@Raptor50aus thanks! Wonder why they're so expensive
@@daMoMenTum I got mine on ebay a little cheaper but it works excellent with all tv analogue tv standards
@@Raptor50aus how much was it
Need one for a low power setup for my party to beam a signal to a CRT projector that has the red, green and blue lights.
That projector has an rf UHF/VHF tuner in it like the ones in regular old TVs.
I have a similar modulator, think it's a Radio Shack, UHF on Ch35 approx 534Mhz from vague memory. I have a large box with three crystal locked VHF modulators on Ch 0 (46.25Mhz), 5a(136Mhz) and ch 11 (225Mhz). I recently got a 2 channel UHF unit has the Ring Grip name (Ring Grip is an Australian manufacturer of electrical fittings). It can be set to any channel in the UHF band.
I have 3 wacom agile units that can go from a-7 to a-1 covers 2 -83 VHF /UHF and 14-22 CATV, 23 to 135 CATV including the channels in the FM band 95 - 99. I use VHF channels for distribution on my home system. Channel 4 stereo Channel 5, 7, 9, and 12 in stereo, and CATV 17. I dont use any UHF because I receive the OTA digital signals with an antenna and mix that in with my analog channels, so TVs throughout the house can get SD material I insert on the analog channels and HDTV. The analog modulators are used for things like my media players, security cameras ect.
Plenty of signals for your TVs then. Correction: the 2 channel modulator has Clipsal (another Aussie electrical supplier) on the case. I did have a look inside it and noticed the board accommodates up to four modulator modules. It’s actually made by Zytec despite the name on the case
@@Wenlocktvdx I have a couple of channel plus units. One is a 2 channel and the other a 3.
quick question I was considering creating a small diy transmitter for personal use but I'm having trouble finding licensing and legality information, would you be able to point me in the direction of resources on this? Thanks!
Well you don't need a license if the power is low. How low depends on where you are. It is based on field strength a certain distance from the radiator (antenna) which varies depending on your country.
There was a pirate that operated for years and years. Probably 20 years and payed nothing but music on the low end of the band. Then one day a high power station was set up on the same frequency and I cont hear it any longer but it was there for many many years.
How do the 'authorities' really 'crack down' on transmitting video or audio ? What's the myth vs reality..did they really drive around in a Van in the early 80s to target 'pirate' video broadcasts? That would be so pathetic.
There was a local pirate that was broadcasting on FM out here pretty much non stop for over 20 years that just one day went off the air. Actually there were 2 or 3 for awhile but they were shut down by industry Canada. I have tapes of one of them, that I have shown on 6he channel.
Nice video Dave, mni tnx.
Nice design. Nowadays they would throw some connectors and a chip on a board and shove it in a cheap plastic case and sell it and it would fail in a week. At least this you can fix. Any ICs on the other side?
Nope. What you see is all there is. 4 little transistors.
Casio made a 1.6" color LCD set, the TV-100.
Big deal. We aren't talking about LCD TVs. Making a 1.6" LCD is nothing. LCD is very simple technology. Have had them on watches for years. This is a 3 gun 1.5" color picture tube and that is a very complex device when it gets that small. Big picture tubes were easier to make. Small ones not so easy because you have to cram all the same elements into a very small space in the jug, suck out all the air and apply some very high voltages. The tolerances are in the microns. Oh and they are built by hand too. LCD you take a piece of glass put a photo resist on it , put a film mask over it, hit it with UV light to expose the photo resist, devoloped it and wash the glass with acid to create your conductor paths. Apply the transparent electrodes, fuse the glass pieces and stuck on drive electronics on the flexible boards around the edges. A couple of polarizing filters and color for filter over the pixels and a light source. Done. A machine stamps out hundreds of them an hour.
Good evening fromm Greece. I have the same HITACHI tv
They don't build em like they used to.
I would like one but seem really hard to get in UK can only see 2.4 ghz ones on ebay
Just saw a VHF-UHF transmitter on eBay for 188 sovs, which is TTP.
just like communicators in space 1999 i think they were sony though
...... "Helena, .....Helena this is Koenig."
"I'm spending the night with Maya"
Would it be possible to recreate this? The circuit seems simple enough.
Of course it would be possible to build one of these. Of just tape a small tunable modulator and add a small amplifier stage.
What’s the range on the video sender?
About 100 feet.
Is there anyway to get something like this? I tried with the amplifier but it didn’t really work well with the straight antenna
I remember getting portable crt tv in 1999 and broke it and late 2003 had vintage 80s crt portable tv from sisters friend crt was on its way out finally in 2005 crt died and also had red clock radio portable tv combo but bad power cord fried everything
Apair of 2n3866 work great.
I don't recall them being illegal in the U.S. I had heard of one brand called VCR Rabbit.
Hitachi, Hibachi
The ones that operated on 900mhz, 2.4 and 5.0 GHz and came with a receiver that hooked to the tv were fine. VCR rabbit, waveform jr (and Sr) and a few others were fine. It was just the ones that operated on uhf tv channel 15 that they stopped selling after a few years. I got that info from a store that was selling them off cheap. Said they couldn't get any more because they banned them due to possible interference with broadcast stations and all future ones would be on a different band.
@@12voltvids These things were always illegal here in the UK, but that didn't stop people getting hold of them of course :) Very useful devices indeed. As for that offset-angle CRT tube, Sinclair Research (yeah the same company that made the ZX series computers) made a small TV over here that used the same technology back in the day. It was called the TV80 (also known as the FTV1). was released in 1983 and was a commercial failure, mainly because it was monochrome and at that time, Sharp had already started developing small colour LCD panels. A cool and fascinating device though, and not too expensive on ebay compared to many tech products of that era
@@countzero1136
The sinclair device used a similar technology. They were using an electrostatic deflection tube, and Sony used a magnetic deflection tube which found itself in wide spread use in door intercom systems. I see them in homes all the time. At the front door a camera and speaker, and in the house a 4" flat CRT monitor. Of course now they are all LCD, but back in the 80s and 90s and as recent as early 2000s companies such as enterphone, used these Sony tubes in their intercom systems because they were flat and could be built into a wall mountable unit. There are still thousands of them out there in service.
Where can we buy this transmitter ?
Hi, I watch your great channel for quite a long time, thanks for share all the procedures. Would you let me know where can I find (or DIY) this TV transmitter? Is that there still having existing product? Thanks.
You will have to check second hand stores, Facebook marketplace, eBay ect. I haven't seen them in over 30 years for sale. If you can find a made in Canada "transvid" grab it. They were fantastic and had a relatively long range. I had one once upon a time but have no idea where it is. Will probably find it some day when i am not looking for it and that will be happy times.
The circuit this transmitter
Did you know that with you modulator setup and a 15 dollar (American) antenna booster and a antenna you can have a lot of analog tv channels of your own making
Well they would transmit but not go more than a few feet. I have a 100 watt transmitter set to 434.6 and 439.25 MHz in the ham radio 70cm band. This translates to channel 59 and 60 on the CATV band. With that i could get a few miles to a buddy's place with directional antennas on each side. Am tv signals take a fair bit of power to go any distance.
Sorry but isn't analog tv FM?@@12voltvids
@@GaryTheRCcar
No analog tv here was vesiduial side band. Look that up for an explanation. Think of it as AM but the lower sigeband only went to something like 600khz and the upper on ntsc went to about 4.2 or 3mhz. The color was transmitter as a bandwidth limited double sideband carrier using 2 suppressed carriers at 3.579545 MHz. This frequency was chosen as it is at an odd harmonic. The sound was an fm carrier centered 4.5 MHz above the video and had its own dedicated transmitter. The output was multiplexed at the antenna. The limit on lower sideband was so it wouldn't interfere with the audio of the next channel down. It was a very complex system, far more than pal because the broadcasters had to satisfy the FCC by producing a system that was compatable with the millions of already installed monochrome system. Europe just said fux b/w we will simucast for a few years snd then shut down b/w transmitters. So they had the ability to use more bandwidth which resulted in a better picture with a much simpler system.
Now FM video is used in analog as well for microwave links and satellite transmission where having a channel bandwidth or 30 or 40mhz no big deal and it looked fantastic. These little VCR senders uses 2.4ghz FM. Lots of ham radio tv guys including me modified them to run in the ham bands.
I am suprised how little their is in there. would would think transmitting video would require more electrnics.
Analog TV was transmitted by amplitude modulation. Actually vestigial side band, so a broadcast transmitter would have additionally filtering, but it is still AM, just with the lower sideband reduced.
To make an AM signal you generate a carrier (1 transistor oscillator) Mix in the modulating signal, in this case the video. 1 transistor will do that too. Generate a second carrier at 4.5MHz and input the audio signal to a varactor diode in the oscilator. This will create an FM signal, which is mixed with the carrier and video mixed signal. (1 more transistor) and then a final output amplifier (1 transistor) so 4 transistors is all that is needed. Really quite simple. Add a few more amplifier stages for more power.
How you send signal to tvs ?
Well this little transmitter transmits on uhf channel 15 which is fine if none of the local channels are broadcasting on 15. All my TV's still have analog capable tuners.
@@12voltvids thanks for info
Why did it not have a 3.579545 Mhz crystal for colour?
The transmitter is not generating color or demodulating color. All it is doing is taking the incoming video signal, which would already have the color encoded on it and AM modulating it onto a UHF carrier and then amplifying it slightly and sending it to an antenna. Its a very simple process.
@@12voltvids Sorry, I still had the modulator mindset LMAO my bad.
@@MikinessAnalog
A modulator is no different. It takes an existing VBCS (video, blanking, chroma, sync) composite video signal and modulates it on a carrier. Most modulators will have a crystal for the carrier generation so they remain stable. This one doe not, so it has a tendency to drift, but the AFC on the TV takes care of that.
@@12voltvids As i understand it from university, the higher the frequency the less power needed to go the same distance, so I'm assuming being UHF it is probably in the 200mW range? I made a 1 watt FM radio transmitter when I was 19 (77.3 Mhz FM with a 19Khz pilot tone crystal for stereo) and it traveled about 3km.
I actually found one of these at a thirft store
Lucky
actually, now see a china one that is 0.5 watts for £88 seems ok price and it would be best to use channel 60 or above here
The tv band here now ends at channel 59. Frequencies starting at 60 is now in the cellular band and with all the antennas the cell companies have it wouldn't take long to find someone jamming their frequencies.
Do you have the schematic _?
No
I can make one for cheep and I can transmit on channel 3 4 and 6 channel 6 I can pick up on fm 87.7
Just picked up 2 of these on ebay for $20 for both
Can you send me one of these? I want to find one that’s sold on Amazon
I really want to broadcast a channel that can be accessed by all people that can only transmit by analog so you can use the old tube TVs
Cause I have a show that I really like and it only ever gets posted on RUclips or other social media platforms for example, like a a Instagram Facebook no I think they only have announcements on Facebook. I have to get permission from them first. If they don’t respond I’ll try and email the people that make the show.
No. I only have 1 and I use it.
I make my own
give that tv a little percussive maintinance
i need one
Look on eBay they do come up once in awhile. I'm hanging onto mi e obviously because just like my am stereo and FM stereo transmitters use them to play with my old radios and TV's.
LibreELEC
Oh fuck yeh mine need a repair mine PAL I think 😄
Needs a fresh build... Can use sky slx link through aerial ....maybe could boost signal from it
Mine got 2 shields inside containing few components
But looks similar
the shadow mask and dot pattern are delta but the gun is still inline, same as on the GE portacolor and most computer monitors
I believe I covered that in the tear down of the little 1.5" panasonic. An online gun allows for static convergence.
Hello! How does one go about sending things in to the channel?
Contact me by email.
@@12voltvids Okay, I don't see any contact info on your RUclips or donation pages. If anyone can point me in the right direction I would appreciate it!
@@deanrauch1061 It is on the main page but here it is for you. volt@telus.net
Does your wife knows about your thn girl friend and this gift?
There's an idea.
Cool watch too..😊
Very much enjoyed this. I have that mini panasonic unit somewhere. I love crt. My main tv is a huge sharp flatscreen.
There is just something cool about crt. I love the x-y scope I just got for my vector clock board.
My main tv is a 63 plasma I have been enjoying now for 10 years.
I have a Sony watchman
Can someone help me understand because I'm new to this, why does everyone say this is illegal? This information is available from the FCC directly. My understanding is that as long as you're under 3 KW of power and your antenna is less than 200 ft then you're completely legal.