Random Video - Viewer Question - Using A function Generator for RF Work (Poor Audio Quality) :((
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- čas přidán 25. 07. 2024
- I didn't realize until I began to edit this that there was an issue with the microphone. As a result, the audio quality is not up to par.
I'm posting this video to answer some questions about using one of the common function generators to do RF and radio work. Function generators are very versatile, but not the best for RF work. Hopefully, we can cover a few techniques that can help with using them for basic radio service. I also cover carrier signals and modulation (both AM and FM). - Zábava
This has got to be the best video about signal generators and oscilloscopes I've seen yet. Thanks so much.
great job on explaining the usage of a function generator, I know this video was made quite a while ago but the information was so informative. Just a great job.
This is an excellent video that needs to be saved to a playlist combined with your other videos for connecting the equipment to a radio.
Tony, you are the best. I get it. You erased 50 years of ignorance in less than 45 minutes. Very very grateful.
This is exactly the kind of explanation that I've been looking for, for years now. Most ppl wont have thousands to spend on gear to tinker around with old radios. I just gave up on trying to figure this out cuz of the lack of info out there. Bravo Tony!
Thank you so much. I have been trying to understand this for a while now and I had a pretty good idea of how it worked but you just laid it all out perfectly. I totally get it now. Again, I can't thank you enough.
Excellent video! Been looking for a video on this....thanks!
I got used to the audio after about 30 seconds, so it didn't distract from the huge amount of great information, thank you!
Excellent videos like this are much need it. you see videos of radio repair, but no one talk about the
equipment, what is the right staff or how to hook it up. Thanks
Great information that I had always wondered about. Thank you for your videos. Paul
As a very economical and versatile unit for the hobbyist, I recommend the "TinySA". It's a handheld spectrum analyzer and signal generator from a few kHz up to 960MHz (and up to +16dBm output). The generator part can me modulated by selectable frequency, and AM/FM-modulated. Sweep-function is also available. Compared to the abilities, this device is "dirt cheap". 73's.
Have you tried it Yet and did it work? The newer one is the Tinysa Ultra? is better and bigger screen
Thank you so much Tony! awesome video!.
Great explanation of how AM works! I'm new to radio stuff and you made it look so simple. It would be great if You could do another video about FM. Keep up the good work!
He has, czcams.com/video/olKIbmWFGIY/video.html it takes a bit of
digging but he has a few. I've given up nagging him to
create some playlists and made my own called
'xraytonyb fun lessons', if you want to copy it
go to my channel, playlists and save it.
It's not complete, but there's a fair bit.
Thanks Tony! Enjoyed watching.
You are an amazing teacher!!!!!!!
Brilliant Tony - thank you. 👌
Very interesting, need to learn more!
Thank you! Most information about this subject I have ever seen. 73, Ray AA4EZ
Thanks Tony that really helped a lot!
Nice one. Sounds like you had to fiddle with audio to get it usable,
I bet the wave looked fine until you came to edit. Well done
and thanks for ssssssssssssharing : )
Fantastic video, thank you
One of my favorite videos. Learn so much here. Been looking for an affordable way for me to offer this service. Problem is I don’t get enough requests to make the investment yet. Sure would be nice to build a kit for it. It’s out there just haven’t found it yet.
Came for the viewer question ... stayed for the poor audio! D; xD
Nice information thank you
Please do the " DB thing " video ! very informative......cheers.
awesome video... I have a yamaha cr-2020 that has no FM at all just static and I'm trying figure out why. AM and all other inputs work fine. I would like to see a video on hooking up the signal gen to the radio and where to take readings and what to expect.
I have shown this in many of my previous videos. The problem is that I didn't categorize these videos to make it easy to find. I never thought anyone would be that interested in this stuff, so I just ran the camera and posted the videos. Hindsight is always 20/20 !
@@xraytonyb awe..... you don't happen to remember the names of the videos do ya?
My signal generator goes to 20 Mhz., and I'm trying to troubleshoot my vintage Pioneer receiver, but don't have access to a 100 Mhz generator. Can I start injecting a signal into an FM radio starting with the IF stage at 19-38 Khz. and of course continue signal injecting along into the audio stages?
Great explanation of AM & FM modulation. Would be great to see one on FM discrimination and how a FM radio does this. I know how it does it, but could I explain it to someone? Doubtful.
I wouldn't have thought of using a 1 Hz modulation. That was interesting.
Wh is it that some radios specify a 30 % modulated signal, and others as high as 50% for alignment ? I would think using 30 % would end up with a more sensitive radio - or maybe better selectivity.
Thanks.
Question: In the absence of a precision RF signal generator, like your HP, what about the possibility of using one of the better quality FM Stereo home transmitters for calibrating, or at least "peaking", our hi-fi FM tuners/receivers, using an audio signal generator to provide the modulation input? The better units have selectable broadcast frequency and PLL stability. Of course, the output out need some serious attenuation to inject directly, and it would only be at first stage, but seems like it would be better than nothing?
I've heard of others using them, but you would be limited with what you can do. Different tuners require different signals during the alignment process. Some need just a pilot signal for the MPX circuit, and then a full composite MPX signal. You also need to be able to produce an RF carrier signal at very specific amplitudes. This is difficult, if you don't have the correct signal generator and the correct impedance matching. Using one of those stereo transmitters will allow you to possibly peak and center the various stages, but setting the pilot detect or measuring sensitivity will be difficult. You also need to inject a stand-alone composite MPX signal into the stereo MPX section on some tuners.
Hope that helps.
@@xraytonyb Good points, thanks, Tony. So, short of the mega-bucks HP machine, is there a mid-level piece of test gear that you would recommend for FM tuner work?
Do you have to do the modulation on a separate channel on the waveform generator than the carrier? If so How do you combine the two channels so you can put the mixed signal to the radio IF?
Tony, would love to see you do a quick video review of TinySA. It sounds too good to be true for RF hobbyists. Is it?
will it work the TinySA Ultra?
Similar specs to my Marconi 2019, but the green HP display for tge WIN !!
This has been a big question for me. I can't believe we need to resort to multi 1000's of gear just to inject a S9 signal and trace a fault. Give me -73dB and a mod tone and all happy. Is it really that hard? Thanks for making this video. It clears a lot of questions.
Deals are still out there, bought an HP 8656B for little over $200 and it works perfectly, off of ebay not even two weeks ago.
I can't believe that I sat through all of that lol. The presentation was good but I don't know the last time that I have listened to the radio! Even back in the 80's I would only use it to source new music from some obscure FM station and it was cassette tape after that! I always unplugged the antenna from all my car stereos just in case someone new asked to listen to it, you only got to listen to what I had recorded lol.
Come to think of it, I haven't watched TV in the last 5 year's! This is a dying format, could have been better if someone designed an add and talk blocker for the radio!..
One strange phenomenon that I do remember finding by accident is that while my brother was listening to an FM station at one end of the scale and I was tuning up around the other end, I could find a spot that would cancel out his station that he was receiving in the other room! He couldn't work out why his radio would randomly just go silent LoL... Yeah I was a mean older brother 😂... I'm thinking that the two different stations were creating some sort of third harmonic that caused one station to cancel out! Who knows!
Hi Tony, after a lot of work, it's a shame I really couldn't hear, or understand what you are saying. Hearing aids are just that, an aid, not a complete rejuvination of my hearing.
Have you given up on the CT F1250 tape deck?
I think that Keysight is the test equipment brand name of Agilent.
Just to make it more confusing, the medical division kept the Agilent name and the test equipment changed to Keysight!
@@xraytonyb My lab at work replaced all of the Agilent branded function generators with Keysight ones a few years before I got there. The Agilent ones were much better as they were in a much more durable case and they dual channel. I found some of the old ones in the store room when I got there 3 years ago and wondered why they stopped using them and replaced them with the current single channel Keysight ones. Evidently someone before me thought these were upgrades they also ordered some much needed DPSO 4-channel Tektronix o-scopes right before I got there. They came in about 2 months after I started. They were the 2 -channel versions, but when you looked them up on the GSA Advantage catalog online there was a stock picture of a 4channel o-scope. They must have thought they were getting a great deal and saving a couple thousand dollars apiece.
If the function generator can't go high enough for the FM band, couldn't you put it into square wave output so that a harmonic of a frequency it can do lands in the FM band?
You can do that. czcams.com/video/F66rsJAhAF0/video.html
This is precisely how the old signal generators worked. This is why generators like the EICO 324 and those types did not output a pure sine wave. The distorted shape of the sine wave would produce harmonics, which would be the two upper frequency ranges. A square wave would produce a bunch of harmonics and might interfere with your alignment. The slightly distorted sine wave in these old signal generators only produced one or two harmonics before the amplitude would drop way off. Pretty smart of those folks back then! It always amazes me how engineers back in the 1930's to the 1960's came up with innovative solutions like this! That's why I am such a fan of vintage electronics!
@@xraytonyb Now everything makes sense.
I have one of these: www.radiomuseum.org/r/conrad_signalgenerator_sg25sg_2.html
And I've always wondered, why it wasn't possible to get a nice clean signal out of it. One half of a cycle is always cut off at half of the amplitude.
Sounds like you're over driving the microphone turn it down a bit and turn it up in post production and will get rid of any background noise
That was not background noise, that was interference. :(
The new camera has selectable microphone response curves for external microphones. I was using a lapel mic with a low gain preamp, but the curve was set to a high gain shotgun type mic. It took me a while to figure it out, once I noticed the issue with tis video. Too damn many settings on this camera!
What is the signal generator THD at 1 khz?
0.1%. As far as I know the HP / Agilent 33120A has the best THD in this price range:
The advertised spec for the DG4162 is
Hi, can a waveform generator cause tinnitus behind a wall? My neighbor is a radiology technician and she does not like my motorcycles and she has an attitude towards me. Out of nowhere I started getting ringing in my ears and clogging my ears. And it's only when I'm home.
sorry.. the sound is just grrrrrrrrrrrrrrrrrrrr............. ill wait for the book..
Tony another Great Video! I have a lot to learning, you explained that you need the Maximum SG to be over 110mhz for Fm but not the minimum for AM would be 540k? if looking for one will they go that to the low Spec? and does this have RF output? ( needed for Pioneer sx- aliment / tuning ?)