Another great video Mike, thank you very much for doing them! I'll be building one of these very soon. One thing that works testing Icom (or other brand) HF radios, is to use a mobile mic from VHF/UHF that has a touch tone keypad on the back. The touch tones are two harmonically unrelated tones. So just press the PTT and press/hold one of the touch tone keys. If you want a single tone, press two keys at the same time in any row or any column. Both buttons must be in the same row or column. Most 8 pin mic plugs from Icom are wired the same but I always check the schematic of both the radio and mic before plugging it in. This is no where near as nice or as powerful and versatile as your project, but in a pinch and one needs something fast...
Nice elegant simple circuit. Built one of these using 741 op amps. Was WAY more complicated. Now my HP service monitor supplies the two tone for me. Nice Video.
Figured I would use one of the super simple design's for ease of locating parts. This circuit could use NTE123AP or 2N2222 transistors in place of the ones I used. Most people that have even the most basic components on hand can probably build this without having to order anything.
@@mikesradiorepair, you mean I won't have to dig through my torroid and MMIC collection to build this? :) Thank you for this video. I could use my service monitor for 2-tone testing, but it weighs 65 pounds, and I find myself doing more each day on site with my 'toys', my NanoVNA, TinySA, and hand-held Tek scope. It saves a lot of hassle having a 'little black bag' of tech tools so I can go do house-calls instead of dragging gear back to the shop. A small, self-contained 2-tone generator was something I lacked. But I won't for long. Thank you.
At 20:00 the tone on the left is the highest frequency audio tone and on the right the lowest audio frequency signal because with LSB modulation the RF spectrum is inverted compared to audio spectrum. Otherwise, thanks for the informative video! de YL3GU
fantastic video Mike., This is why I keep my broken Sencore CB42 on the bench. Audio generator still works. Has a "SSB tone", 400 and 1 k tone. I also have a Kenwood SM-220 with a built in tone generator that puts out 1k 1575 and dual tone. Thanks for sharing.
I just received a TRanse Transalyzer Mark III (no letter) that has a built in 2 tone generator. Can't find a schematic anywhere for it, but this video will help me at least calibrate/balance the generator. Only problem is that absolutely nothing is labeled on the board. But I did manage to figure out that the three blue VRs are for the tone generator. Now I just have to figure out which VR does what.You two have solved a lot of mysteries for me.
Awesome video, one of your best, it complements a video that Peter did over on the TRX Bench a few months back very nicely. Not sure if you hear this enough but, thank you for taking the time to make these video, they are appreciated, at least by me and I am positive by many many others. You should take joy knowing that you are adding to the common good, Keep up the great work!!! 73
It's a good idea, because it stops possible problems before they have a chance to start. But it's not really necessary if you aren't pushing out 1,500 watts, and are running a good dummy load and coax cable to keep your RF from leaking.
Hello. Nice video and quick question: could ceramic caps be used where you are using the green ones? Unfortunately, I don't have any of the green ones handy but I do have plenty of ceramics. Thanks.
I had never seen the Vishay-Spectrol pot adapters before; have a good selection of the pots and should get a couple just to have on hand, but boy they're a little pricey considering what they are!
Mike, I notice that most guys in their repair videos use some sort of lead insulators, for capacitors, etc with long leads. Can this be accomplished just as well with heat shrink tubing? Thanks. Mike
Never mind; the schematic looked like it said BC5479, but it was BC547B - couldn't find me a BC5479! That's what I get for watching RU-vid videos late at night!
hi mike, i have been looking all over for those trim pot handle extensions, so you can use a knob on them..where do you get them ? kevin rea lancaster, calif.
Mike, Very timely. I built a 4 channel generator 30 or so years ago and haven't located it yet. If you didn't want to wire into the mic jack, you could take the output of the generator to a speaker and put the mic up to the speaker. Here's a link to the circuit. radiotransmitter.wordpress.com/2016/01/07/a-simple-2-tone-generator-for-testing-the-linearity-of-ssb-transmitters/ WB3BJU
Basically like my B&K 1040. It has a built in speaker with (for a lack of better words) a foam cup to hold a microphone on. If you wanted to make a speaker box like this you could salvage a "foam cup" off of a set of headphones.
Hi Mike.I built your two tone generator twice.I trashed the first one and started over again.I'm pissed because I still don't think its working.I get some signal on my dso138 and some on my 465b'but its not right.I would like to send it to you so you can tell me what I did wrong.Send address to send it to and I will send money along for return postage.Tnx Ronnie
OK this is for Mike, but anyone else that might be able to help!, I have built my 2 tone generator, I have looked at audio tones on my spectrum analyzer, and they are both at same amplitude, but when I run it on radio it is so far out on amplitude, can anyone shed some light for me please? Thanks.
Most of what I saw was OK but during the presentation I became lost because more detail on what was going on was not given. When I was going to College I had a Professor who was from Peru who was good but should have been teaching at a University or at a Graduate University as He was that good but he could not come to OUR Level to teach those just beginning their higher education, he would write on the blackboard a problem then turn to the Class and ask "RIGHT or WRONG"??? We would look at one another and shake Our heads because We did not know what to say and many of the students were lost in what was going on. I learned that over 75% of the Students he taught failed his classes no matter if it was Algebra to Calculus. I learned from another Math Professor to give every step needed in detail how a problems was solved and stopped to ask if anyone was lost in any of the classes He taught. He was voted best Professor at that College because of the high average of Students who passed His Classes. In this Presentation was OK but lacked many of the details needed to explain what was going on I wanted to know more but got lost because of the lack of detail. I learned from that Professor to give as much Detail when I teach anyone something so the next time they do what I taught them, they know what to without MY Help.
