Band spread, that is a good idea ! Haven't thought of that. For some more explanation of the working of that band spread condenser shown here: if you put two capacitors in series, the calculated outcome value is (C1 X C2)/(C1 + C2). Let say C1 is the variable capacitor, and it is set on 5 pF, and the fixed cap is 10 pF, then the total value will be (5x10)/(5+10) = 50/15 = 3,3 pF 10 pF, and the fixed cap is 10 pF, then the total value will be (10x10)/(10+10) = 100/20 = 5 pF 20 pF, and the fixed cap is 10 pF, then the total value will be (20x10)/(20+10) = 200/30 = 6,6 pF 50 pF, and the fixed cap is 10 pF, then the total value will be (50x10)/(50+10) = 500/60 = 8,3 pF 100 pF, and the fixed cap is 10 pF, then the total value will be (100x10)/(100+10) = 1000/110 = 9,1 pF 250 pF, and the fixed cap is 10 pF, then the total value will be (250x10)/(250+10) = 2500/260 = 9,6 pF 500 pF, and the fixed cap is 10 pF, then the total value will be (500x10)/(500+10) = 5000/510 = 9,8 pF Here you see clearly that with a large variable capacitor you can adjust a value much smaller, but it is NOT lineair.
Neat! My Hammarlund HQ120-X HF receiver has a huge bandspread dial and capacitor right next to the equally large VFO dial and cap. They were once common in multi-band HF receivers but the newer transistor radios are so easy to tune they seem to have taken most of the joy out of all that manual tuning people did back in the day. However, with videos like these the mysteries of how old tube radios worked are finally revealing themselves. Thanks for the lesson on how bandspread works - I'm sure I will find it useful.
I've used band-spreading on many of my homemade shortwave radios, mainly using small value tuning capacitors. I quite like the switch idea, because even 5MHz to 30MHz over 3 bands, the band-spreading range is quite noticeable between band 1 and band 3. My latest 3 Band shortwave radio has band-spreading, but here I'm using electronic tuning, with a varactor diode, in fact i'm using a 1N4007 diode, which does the job well and with a 100k resister into a 10k control pot, stabilised with a 5.6v zener, I'm very happy with the result. Frequency drift can always a problem, but the 5.6v zener, dropping down from 9v works fine. Great video for those getting into radio projects.
I am glad to see and hear you are well and were not affected by the storm. The band spread function is a lot of fun to play with. I have it on my Hallicrafters and it works remarkably well. Take good care.
Very interesting. Until I got into the Satellit-type radios I didn't pay much attention to shortwave. I was more interested in the FM sound quality of valve radios. Shortwave, Bandspread, BFO and SSB got me into a new territory of curiosity. Having looked at how the 'Lupe' part works on some of the radios I have it had occured to me that it wasn't that complicated in terms of functionality. What you have done is put that idea into reality. I've always been interested in radio in general and this has opened up that interest again. This experiment you have done is great and a lot of fun for sure! Love it!!
I too wondered just how difficult it would be, and found it was actually quite easy. My interest in shortwave is more technical than really as a listener, but that’s what the hobby is for.
I had a radio that had a band spread for Radio Luxenbourg. I was interested to see how they did this as it could be fine tuned. When you looked for Radio Luxenbourg you found it, but it was very week and there and gone in a slight turn of the dial and was almost impossible to tune on most radios up here. On a small transistor radio it would drift or the slightest touch of the dial, even just picking up the radio was enough to knock it off the station. Flicking the "Fine tune" as they called it spread the station and it was a lot easier to tune. All I found was that they had fitted a capacitor across the tuner capacitor. So I changed the switch the a two or three way (can't remember it was so long ago) but I fitted another small tunable capacitor across it when I flicked the switch. This made it much better to tune all the stations, get them so you could hear them, hit the switch and turn the new capacitor to tune it in better. It was just an experiment and it appeared to work, the factory just had the band spread only for Luxenbourg. It was an old radio with battery power so there was no danger, I was still at school (primary) and it also helped with Radio Nordsee/Northsea, Caroline, Big "L" and a couple of others. Those were the days, listening under the blankets and my parents and school teacher wondering why I was so tired during the day. I just thought that if a fixed capacitor worked a variable one might work as well. Some stations for some reason it didn't work on, but I didn't care, they were quite strong anyway. I think this was my first ever dive into anything like a radio. I was very young and surprised I was allowed to do it. I learned to solder very quickly and that soldering irons were very hot! I borrowed my fathers soldering iron and solder, it was no use to him anyway, his idea of a fix was to twist wires together and use sellotape! 8-l The TV repair man first words when he walked through the door was "What has he done this time to upset it?" lol
I knew from your facial expression this was going to be an informative, as well as a fun video. From there, it certainly lived up to expectation. I thoroughly enjoyed seeing, and listening to your experimentation. Being an apprentice trained “telly and audio” repair man (now retired), the syllabus did not include the type of electronics seen in this video, consequently It was after achieving my Amateur Radio Licence I began to learn about this stuff 🙂 Thank you very much my friend, Phil
The in-person view really helped when you were explaining band-spread, good show :D You have more guts than I do :) Cheers and have a good new year now.
Ok. Let’s correct that: Muito obrigado. now you can say you speak a little Portuguese 😊 As for the video, I really enjoyed playing around with this. A lot more can be done with varactor diodes, but I’ll have to wait for the inspiration to kick in.
Great idea, for a more permanent haçk you could put some variactor diodes in and have a potentiometer with a battery on a cable so the case isn't touched.
Seems to work very well Manuel. First I thought you were talikng about a sort AFC like in FM band. You brouhjt me to an idea. For now A happy new year, hope it will be a better one.
Ha great fun indeed. Can use a 1N4148 diode biased in reverse as a varactor. This will be a much smaller capacitance variation and thus will be more linear when put in series with a small cap. Happy New Year!
The intro is like a tv talkshow. Two things missing, a suit and perhaps an old Grundig mikrofon in one hand. Lol Great work sir, I will continue trying to understand the theory.👍
Manuel, A fun experiment with junk box parts, it's nice that your introducing us into experimenting, certainly Band Spread and selectivity are features generally only found on communications gear. Suggestion: see if you can find a WW-II era shortwave radio to restore.
@@electronicsoldandnew Well as long as your “volksempfanger” an interesting collectible, the idea of a government subsidizing receivers that only can receive its propaganda, maybe governments can develop Internet systems that only hear their side of the story, oh yes there is one of those is there.
You know, some tube sets from the late 50's / early 60's used FM tuning circuitry as a bandspread for AM. No BFO in them, though, so you could not decode CW/SSB signals but tuning AM broadcasts was easier.
After watching that had to try it . Now my Philips 170a is now sporting a b.n.c connector at the rear of the chassis .screened cable to the oscillator stage. Allso I've had for years a nice art deco bakelite box dont know what it was used for .but you dont need to be a rocket scientist to guess what's going in it now .allso I've had for years a slow motion drive unit that's going to drive the tuning condenser .and a period selector switch for the caps .(waffling on a bit) lol a print off a tuning scale .a nice brass pointer glass front and Bob's yer Uncle. B f o next going to fit it all in the same Bakelite box .quite exciting really ps had a lovely holiday in Madeira in Funchal's outstanding gardens
Seems I really got you going 😊 Be careful, however, with the effect of stray capacitances on the total value of the “extra capacitance” that you will be adding to the oscillator tuning cap. Just a short piece of extra coax can easily add another 10pF or so, which means you can’t get down near zero.
@@electronicsoldandnew yes just getting started on old radios about 6 months ago I recaped my old vox Ac30 ( i brought it in 1974 ) I got my inspiration and confidence by watching a TH-cam channel called( Uncle Doug's ) restorations on guitar amplifiers. He goes in to great detail .on breaking down all the different stages. That's why I find your videos so inspiring allso I built a smaller version of your current limiter with a isolating transformer which works fine .by watching his and your videos over and over again it all starts to make sense .its quite addictive and exciting to learn something new.
I've done the same thing as you to add a BFO to a non-BFO radio by simply putting a heterodyne radio close to the prime radio and tuning it to decode SSB. Of course yours woks better! I think I'll play around with the bandspread idea. I like that. I have a lot of 30's radios to apply those two ideas to. BTW: Can you give a link to the BFO that you have? Just a schematic would be fine too. I lLiked this video and I also like experimenting around here as well.. It was off the beaten path. Happy New Year as well!
Mr Caldeira you could use a varicap with the same results. The advantage is that you use a voltage and a potenziometer that you can position anywhere. As per stability it will be a little less but these type of radios are not very stable anyway
This has given me an idea. I have a tecsu. R9012 and its dial cord appears to have a round wound outer covering (like guitar strings) as tuning ssb can be a hit/miss proposition. Just one creaky bump takes the tuning past the station ans unfortunately, the case is so small that I have to use my home made bfo. Now im thinking maybe if i can find room to install a small headphone plug, I can make another bfo and bandspread in one unit, wired to a stereo plug that can just be added anytime and like Manuel, not permanently install it so it can be interchanged with other non bfo containing radios.
You’ve me thinking Manuel. My FRG-7 is quite easy to tune but not so much for SSB. The fine tune knob is still rather coarse, so I wonder if putting a cap in series with the fine tune cap would help. I’d like to get a bfo for my Digitech AR-1748 (which is identical to the Grundig S450DLX filed radio. Just a rearranged front panel. It has a I.f. out socket which could be used for the bfo.
I'm not sure that your maths is correct. 250pf in series with 10pf is not 5pf. So the capacitor has more effect on the frequency on its lower setting than on its higher settings. Worked well regardless though.
@@electronicsoldandnew Yes but it is not a linear variation like you imply. The mid point of the capacitor doesn't correspond to half of 10pf. Using the formula for capacitors in series, I find the following totals for various settings of the capacitor in series with 10pf: (100pf, 9.09pf) (200pf, 9.52pf) (300pf, 9.68pf) (400pf, 9.76pf) (500pf, 9.80pf)
Hello there I have been trying to understand how it works for side tones I have watched many TH-cam videos but are to difficult to figure it out I came across your site and now I have an idea how to rig it together
Hello Maual , Happy new year to you and may you and your family stay healthy.! I have a question that has nothing to do with this item, but maybe you can give me some directions to a problem that I have; I just restored a KY566 radio, changed all the bad resitors , capacitors etc. after that aligned it again. Now somehow a nasty squeeking osscilation is introduced when I play the radio at FM at a low volume. When I turn it up it dissapears again. I swapped the tubes but no results. It is not the amplifier; the PU input works fine. I know seeing all the reaction you replay to you might not be waiting for my problems , but I give it a try anyway. What I learned so far I mostly learned from you, thanks a lot.
Could be in need of decoupling capacitor to ground in one of two places: Try the point where the B+ goes into the FM unit, or the heater line to the FM front end tube. Be careful of the cap voltage rating. best to use a high voltage one. the value can be small (1nF or so). this may work.
Off-topic: The word 'condenser' -- although Wikipedia says it's the same thing -- sounds a little weird to me. I mean there is nothing to 'condense'. what do you folks think? ;)
The almighty Romanian radio again. But it is good to hear Serbian language on their service. The guy in German is mearly talking about the new strain in the UK. Nothing rude.
People converse about topics of mutual interest..those who share no interest in the topic being discussed find the subject tedious.. radio amateurs are no different,,amateur radio is a fairly narrow aspect of life..antennas interest me much more than does the sex life of reindeer☻ Such is life, in the past, in the present and it will be so in the future..
@@electronicsoldandnew around 37 mins into this interview is the funniest bigfoot incident ever heard Duke id a good man Guy that does this channel from Montana th-cam.com/video/GMV0tq5H1H4/w-d-xo.html
Band spread, that is a good idea ! Haven't thought of that.
For some more explanation of the working of that band spread condenser shown here: if you put two capacitors in series, the calculated outcome value is (C1 X C2)/(C1 + C2). Let say C1 is the variable capacitor, and it is set on
5 pF, and the fixed cap is 10 pF, then the total value will be (5x10)/(5+10) = 50/15 = 3,3 pF
10 pF, and the fixed cap is 10 pF, then the total value will be (10x10)/(10+10) = 100/20 = 5 pF
20 pF, and the fixed cap is 10 pF, then the total value will be (20x10)/(20+10) = 200/30 = 6,6 pF
50 pF, and the fixed cap is 10 pF, then the total value will be (50x10)/(50+10) = 500/60 = 8,3 pF
100 pF, and the fixed cap is 10 pF, then the total value will be (100x10)/(100+10) = 1000/110 = 9,1 pF
250 pF, and the fixed cap is 10 pF, then the total value will be (250x10)/(250+10) = 2500/260 = 9,6 pF
500 pF, and the fixed cap is 10 pF, then the total value will be (500x10)/(500+10) = 5000/510 = 9,8 pF
Here you see clearly that with a large variable capacitor you can adjust a value much smaller, but it is NOT lineair.
Finally, we all can see you! Thank you for great work!
Pleasure.
Neat! My Hammarlund HQ120-X HF receiver has a huge bandspread dial and capacitor right next to the equally large VFO dial and cap. They were once common in multi-band HF receivers but the newer transistor radios are so easy to tune they seem to have taken most of the joy out of all that manual tuning people did back in the day. However, with videos like these the mysteries of how old tube radios worked are finally revealing themselves. Thanks for the lesson on how bandspread works - I'm sure I will find it useful.
Glad it helps.
I've used band-spreading on many of my homemade shortwave radios, mainly using small value tuning capacitors. I quite like the switch idea, because even 5MHz to 30MHz over 3 bands, the band-spreading range is quite noticeable between band 1 and band 3. My latest 3 Band shortwave radio has band-spreading, but here I'm using electronic tuning, with a varactor diode, in fact i'm using a 1N4007 diode, which does the job well and with a 100k resister into a 10k control pot, stabilised with a 5.6v zener, I'm very happy with the result. Frequency drift can always a problem, but the 5.6v zener, dropping down from 9v works fine. Great video for those getting into radio projects.
The varicap works well. I don’t want to add this as a permanent feature, or i’d definitely go that route.
I am glad to see and hear you are well and were not affected by the storm. The band spread function is a lot of fun to play with. I have it on my Hallicrafters and it works remarkably well. Take good care.
thanks 😊
Very interesting. Until I got into the Satellit-type radios I didn't pay much attention to shortwave. I was more interested in the FM sound quality of valve radios. Shortwave, Bandspread, BFO and SSB got me into a new territory of curiosity. Having looked at how the 'Lupe' part works on some of the radios I have it had occured to me that it wasn't that complicated in terms of functionality. What you have done is put that idea into reality. I've always been interested in radio in general and this has opened up that interest again. This experiment you have done is great and a lot of fun for sure! Love it!!
I too wondered just how difficult it would be, and found it was actually quite easy. My interest in shortwave is more technical than really as a listener, but that’s what the hobby is for.
Excellent description.Thanks.
Pleasure
I had a radio that had a band spread for Radio Luxenbourg. I was interested to see how they did this as it could be fine tuned. When you looked for Radio Luxenbourg you found it, but it was very week and there and gone in a slight turn of the dial and was almost impossible to tune on most radios up here. On a small transistor radio it would drift or the slightest touch of the dial, even just picking up the radio was enough to knock it off the station. Flicking the "Fine tune" as they called it spread the station and it was a lot easier to tune. All I found was that they had fitted a capacitor across the tuner capacitor. So I changed the switch the a two or three way (can't remember it was so long ago) but I fitted another small tunable capacitor across it when I flicked the switch.
This made it much better to tune all the stations, get them so you could hear them, hit the switch and turn the new capacitor to tune it in better. It was just an experiment and it appeared to work, the factory just had the band spread only for Luxenbourg. It was an old radio with battery power so there was no danger, I was still at school (primary) and it also helped with Radio Nordsee/Northsea, Caroline, Big "L" and a couple of others.
Those were the days, listening under the blankets and my parents and school teacher wondering why I was so tired during the day. I just thought that if a fixed capacitor worked a variable one might work as well. Some stations for some reason it didn't work on, but I didn't care, they were quite strong anyway.
I think this was my first ever dive into anything like a radio. I was very young and surprised I was allowed to do it. I learned to solder very quickly and that soldering irons were very hot!
I borrowed my fathers soldering iron and solder, it was no use to him anyway, his idea of a fix was to twist wires together and use sellotape! 8-l The TV repair man first words when he walked through the door was "What has he done this time to upset it?" lol
I can understand that perfectly. I used to tinker with electronics until the early hours of the morning, then almost fall asleep in school 😊
"Broadsword calling Danny Boy". 16kilos. Think I heard "English problem".lol. Thanks Mr C for a great channel. ATB for the New Year.
Thanks, and the same to you for 2021.
I knew from your facial expression this was going to be an informative, as well as a fun video. From there, it certainly lived up to expectation. I thoroughly enjoyed seeing, and listening to your experimentation.
Being an apprentice trained “telly and audio” repair man (now retired), the syllabus did not include the type of electronics seen in this video, consequently It was after achieving my Amateur Radio Licence I began to learn about this stuff 🙂
Thank you very much my friend, Phil
Thank you Phil. Glad you enjoyed it. Happy new year
It appears to work extremely well, Manuel, great. Happy New Year.
Happy New Year
Fantastic idea. I am off to build one of these. Excellent idea.
Have fun.
The in-person view really helped when you were explaining band-spread, good show :D
You have more guts than I do :)
Cheers and have a good new year now.
Now i see the face of Electronic Magic thank you , May you and yours have a Happy new year good health to all you on the Island of Madeira .
thanks. and happy new year to you and yours
Muchas gracias Manual, excellent demonstration of bandspread and the BFO, very well done. I speak a little Spanish... well that's it really, Cheers 😉
Ok. Let’s correct that: Muito obrigado.
now you can say you speak a little Portuguese 😊
As for the video, I really enjoyed playing around with this. A lot more can be done with varactor diodes, but I’ll have to wait for the inspiration to kick in.
Mr. Caldeira, there is an amazing difference in the perception of a movie when you are seen. I hope you keep this style ;) Happy New Year :D
I just might. I actually like it.
Happy new year
Much more engaging now you're doing your piece to camera. Happy New Year :)
😊 Happy New Year
Haha you picked up the robots from star wars! Well done :D
True.
Now that was really fun!
👍
Most interesting. Happy new year.
Happy New Year
Great idea, for a more permanent haçk you could put some variactor diodes in and have a potentiometer with a battery on a cable so the case isn't touched.
I actually started looking into that, but time became scarce.
Damn, I was going to suggest the same thing. Love your channel. Wishing you and yours a Happy New Year!
👍
Great experimenting!
👍
Seems to work very well Manuel. First I thought you were talikng about a sort AFC like in FM band. You brouhjt me to an idea. For now A happy new year, hope it will be a better one.
You probably mean using the “error” voltage drop to drive a varicap diode ? It’s a good concept and should be able to work with some experimentation.
Ha great fun indeed. Can use a 1N4148 diode biased in reverse as a varactor. This will be a much smaller capacitance variation and thus will be more linear when put in series with a small cap. Happy New Year!
Thanks. Happy new year.
Well that is impressive!
👍
The intro is like a tv talkshow. Two things missing, a suit and perhaps an old Grundig mikrofon in one hand. Lol
Great work sir, I will continue trying to understand the theory.👍
thanks 😊
Another good video. Hope you were affected by all the recent flooding
No, not affected at all.
@@electronicsoldandnew pleased to hear it, looked pretty bad, rocks and mud etc all over the place..
true. scared the hell out of us.
Hope you’re safe from the floods ?
Keep up the good work on the videos, highly entertaining and informative too 👍🏻
Yep, no problem, and thanks
bravo
thanks Dan
Manuel, A fun experiment with junk box parts, it's nice that your introducing us into experimenting, certainly Band Spread and selectivity are features generally only found on communications gear. Suggestion: see if you can find a WW-II era shortwave radio to restore.
I actually have someone trying to get me a “volksempfanger” which is even older than that. We’ll see.
@@electronicsoldandnew Well as long as your “volksempfanger” an interesting collectible, the idea of a government subsidizing receivers that only can receive its propaganda, maybe governments can develop Internet systems that only hear their side of the story, oh yes there is one of those is there.
There certainly is 😊
Incredible usefull.
👍
I use a modified Hustler 27 TD 5/8 Vertical for 40 m with 3 radials. Awesome.Thanks for asking.
😊
You know, some tube sets from the late 50's / early 60's used FM tuning circuitry as a bandspread for AM. No BFO in them, though, so you could not decode CW/SSB signals but tuning AM broadcasts was easier.
👍
After watching that had to try it . Now my Philips 170a is now sporting a b.n.c connector at the rear of the chassis .screened cable to the oscillator stage. Allso I've had for years a nice art deco bakelite box dont know what it was used for .but you dont need to be a rocket scientist to guess what's going in it now .allso I've had for years a slow motion drive unit that's going to drive the tuning condenser .and a period selector switch for the caps .(waffling on a bit) lol a print off a tuning scale .a nice brass pointer glass front and Bob's yer Uncle. B f o next going to fit it all in the same Bakelite box .quite exciting really ps had a lovely holiday in Madeira in Funchal's outstanding gardens
Seems I really got you going 😊
Be careful, however, with the effect of stray capacitances on the total value of the “extra capacitance” that you will be adding to the oscillator tuning cap. Just a short piece of extra coax can easily add another 10pF or so, which means you can’t get down near zero.
@@electronicsoldandnew yes just getting started on old radios about 6 months ago I recaped my old vox Ac30 ( i brought it in 1974 ) I got my inspiration and confidence by watching a TH-cam channel called( Uncle Doug's ) restorations on guitar amplifiers. He goes in to great detail .on breaking down all the different stages. That's why I find your videos so inspiring allso I built a smaller version of your current limiter with a isolating transformer which works fine .by watching his and your videos over and over again it all starts to make sense .its quite addictive and exciting to learn something new.
I’m honoured to be on the same menu as Uncle Doug. He was one of my inspirations when I started getting more into this hobby.
Thank you - i like foundations
👍
I've done the same thing as you to add a BFO to a non-BFO radio by simply putting a heterodyne radio close to the prime radio and tuning it to decode SSB. Of course yours woks better! I think I'll play around with the bandspread idea. I like that. I have a lot of 30's radios to apply those two ideas to.
BTW: Can you give a link to the BFO that you have? Just a schematic would be fine too.
I lLiked this video and I also like experimenting around here as well.. It was off the beaten path.
Happy New Year as well!
This is the last video in the BFO project.
th-cam.com/video/YLHVP_WaM_U/w-d-xo.html
Mr Caldeira you could use a varicap with the same results. The advantage is that you use a voltage and a potenziometer that you can position anywhere. As per stability it will be a little less but these type of radios are not very stable anyway
True. However, this was just a little experiment, as I don’t intend to add this as a permanent feature.
This has given me an idea. I have a tecsu. R9012 and its dial cord appears to have a round wound outer covering (like guitar strings) as tuning ssb can be a hit/miss proposition. Just one creaky bump takes the tuning past the station ans unfortunately, the case is so small that I have to use my home made bfo. Now im thinking maybe if i can find room to install a small headphone plug, I can make another bfo and bandspread in one unit, wired to a stereo plug that can just be added anytime and like Manuel, not permanently install it so it can be interchanged with other non bfo containing radios.
👍
You’ve me thinking Manuel. My FRG-7 is quite easy to tune but not so much for SSB. The fine tune knob is still rather coarse, so I wonder if putting a cap in series with the fine tune cap would help. I’d like to get a bfo for my Digitech AR-1748 (which is identical to the Grundig S450DLX filed radio. Just a rearranged front panel. It has a I.f. out socket which could be used for the bfo.
Any cap in series with the fine tune cap will reduce its effect, which could work for you.
Manuel, did you do a video of your BFO?
Yes, three actually. Just see the last one for the demo.
Correction. The 1N400x series will make a better varactor than the 1N4148
Yes, the 1n4148 has very low capacitance due to its small inter-layer surface area.
The german radio amateurs don't talk about their antennas, they discuss about the new Covid variant in the UK 😊 Happy new year 💥🍾
😊 happy new year
I'm not sure that your maths is correct. 250pf in series with 10pf is not 5pf. So the capacitor has more effect on the frequency on its lower setting than on its higher settings. Worked well regardless though.
No, 5pf is when the tuning cap is reduced from its maximum. It will vary all the way from near zero to near the max of the small cap.
@@electronicsoldandnew Yes but it is not a linear variation like you imply. The mid point of the capacitor doesn't correspond to half of 10pf. Using the formula for capacitors in series, I find the following totals for various settings of the capacitor in series with 10pf: (100pf, 9.09pf) (200pf, 9.52pf) (300pf, 9.68pf) (400pf, 9.76pf) (500pf, 9.80pf)
😍
Hello there I have been trying to understand how it works for side tones I have watched many TH-cam videos but are to difficult to figure it out I came across your site and now I have an idea how to rig it together
👍
Hello Maual , Happy new year to you and may you and your family stay healthy.!
I have a question that has nothing to do with this item, but maybe you can give me some directions to a problem that I have;
I just restored a KY566 radio, changed all the bad resitors , capacitors etc. after that aligned it again.
Now somehow a nasty squeeking osscilation is introduced when I play the radio at FM at a low volume. When I turn it up it dissapears again.
I swapped the tubes but no results. It is not the amplifier; the PU input works fine.
I know seeing all the reaction you replay to you might not be waiting for my problems , but I give it a try anyway.
What I learned so far I mostly learned from you, thanks a lot.
Could be in need of decoupling capacitor to ground in one of two places: Try the point where the B+ goes into the FM unit, or the heater line to the FM front end tube. Be careful of the cap voltage rating. best to use a high voltage one. the value can be small (1nF or so). this may work.
20:00 min is about corona the virus mutation in german and that they had hear there olso something from it
👍
Great idea. The title says SSD, I think you meant SSB? Happy new year to you.
Ha! Didn’t notice that mistake. Thanks.
So interesting. Just out of curiosity, what is the frequency for those SSB transmissions?
The 40m band is around 7 MHz, and the 20m around 14 MHz.
@@electronicsoldandnew Thanks!
I just remember: lambda = 300 / F, where F is in MHz and lambda is in meters...
close enough :)
Cheers,
😊
Off-topic: The word 'condenser' -- although Wikipedia says it's the same thing -- sounds a little weird to me. I mean there is nothing to 'condense'. what do you folks think? ;)
It’s the older term used.
hams discuss antennas.. Yup. pilots talk about what is the best 2 cycle oil to use in their engines for most life and best cooling properties.
👍
The almighty Romanian radio again. But it is good to hear Serbian language on their service. The guy in German is mearly talking about the new strain in the UK. Nothing rude.
Good. 😊
Q multiplier
People converse about topics of mutual interest..those who share no interest in the topic being discussed find the subject tedious.. radio amateurs are no different,,amateur radio is a fairly narrow aspect of life..antennas interest me much more than does the sex life of reindeer☻
Such is life, in the past, in the present and it will be so in the future..
I fully understand that, as it obviously applies to me on the topic of tube radios 😊
Have a great new year.
B.F.O ?Bigfoot organization lol
Don’t be silly, there’s no such thing as a bigfoot. Now the yeti ... hmm
@@electronicsoldandnew around 37 mins into this interview is the funniest bigfoot incident ever heard Duke id a good man Guy that does this channel from Montana th-cam.com/video/GMV0tq5H1H4/w-d-xo.html
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73 n4jrs
Interesting. Happy New Year!
Happy New Year