I'm really speechless, this is an absolutely brilliant idea! Even though it looks simple in retrospect, I think this solution is really well thought out. I'm sure the developers at Saba or Braun etc. came up with inventions in the same way back then. Unfortunately there aren't enough thumbs up up there, but I've given away the one I could give you. 😉😉
I still can't believe how many SW stations you can get across the pond!! Never ceases to amaze me. His SW dial was filled with activity. The only stations I can get in Utah is WBCQ Maine, USA on 9330 KHz and WWV at 5000 KHZ and both are barely listenable. And I have several SW antennas. All grounded well. I might also get some Cuban stations at times but they are buried in the noise.
That’s a useable effective addition, where I have externally connected bulk hook ups. MFJ-956 with a rotating loop antenna makes it interesting. AOR LA400 has a lot of potential and flexibility too but the technology costs a fortune and is difficult to source these days. I was the only AOR radio distributor in Australia just over 10 years ago. I couldn’t see it lasting so I stocked up on distributor pricing purchases, before business ceased. Keep up the interesting tech ideas. I am still watching now and then between busy times. 👍
I've made many shortwave fine tuning add-ons, from varicap diodes, to adding a small capacitor tuning condenser and adding a small capacitor in series with a large tuning condenser, like your experiment. All of these had to have a knob fitted to the front panel to control the bandspread. Your method certainly gets around that problem. Great job.
Brilliant!!! Doing this to my Grundig without a doubt. You could even fit another 10, 15 or 20pF cap in series, between the main tuning capacitor and that new variable capacitor, with a switch somewhere on the back that shorts it out for lower frequencies and is open for the higher frequency range to reduce it's capacitance accordingly.
The bulgarian veneer furniture of my parents I'm still keeping has two concentric tuning knobs and the inscription on the dial glass says "tuning" and something that translates, i.e. into German as in this radio "UKW und KW Lupe" and works exactly this way (in fact, in Bulgarian magnifying glass sounds and spells in Cyrillic exactly as in Spanish and Portuguese).
Extremely clever and non intrusive. Maybe place a adhesive label on the top of the upper plate if anybody ever wants to remove it? I don't see why they would if they know what it does. This is great work.
I love the simplicity of this solution and as a Saba radio fan, bandspread was not something high on their agenda. I am going to take a peek at how this could be implemented on a Meersburg or Freiburg. I am guessing you had to work through some formulas to determine the right 3D print plate size (and gap too) to hit the capacitance range you achieved (and at the same time get it to fit within the contraints of the radio too). I am wonderig if that took a few kicks of the can to get right?!!! Without a doubt, a very impressive result!
Actually, the first challenge was the fit, with no calculations at all. The separation was achieved by trial and error - the closer the plates, the higher the C. You really only need a small capacitance so it’s not difficult.
A very elegant and reversible solution Manuel. With hindsight it's surprising that the manufacturers didn't do something similar as standard when they had a "rotatable ferret" in the cabinet. 🤣 But with the additional capacitance now controlled by the ferrite rotation (unless you can find a pair of spare contacts on the SW pushbutton switch to only add it for SW) are you seeing an unacceptable interaction between the ferrite rotation and MW and LW station tuning? Not that we have much on either band these days worth listening to so only an issue for those not using an external antenna maybe?
@@electronicsoldandnew Fantastic. If it had been an issue then just connect the capacitor controlled by the ferret to the SW oscillator coil padder capacitor instead as I assume that's switched out when SW isn't in use?
Some radios allow you to fine tune the SW by turning the FM knob, called “short wave log” on my Opus 7. Have you ever explained how that works in any of your videos? If not, perhaps you can describe how that functions in a future video. Thanks
also connect this fine condenser circuit not to main tuning condenser, but to KW coil, so it will work only on KW, otherwise it will influence the turning of MW when rotating FA!
@@electronicsoldandnew In some tube sets with split AM/FM tuning, FM tuning was used for this. In transistor radio maybe varicap controlled by voltage from tone control potentiometer should be added.
I really enjoy saying to myself after watching your videos..”so that’s how it works”. Great idea, great video. Thanks
Pleasure
A very neat solution Manuel.
I'm really speechless, this is an absolutely brilliant idea! Even though it looks simple in retrospect, I think this solution is really well thought out. I'm sure the developers at Saba or Braun etc. came up with inventions in the same way back then.
Unfortunately there aren't enough thumbs up up there, but I've given away the one I could give you. 😉😉
Thank you 👍
I still can't believe how many SW stations you can get across the pond!! Never ceases to amaze me. His SW dial was filled with activity. The only stations I can get in Utah is WBCQ Maine, USA on 9330 KHz and WWV at 5000 KHZ and both are barely listenable. And I have several SW antennas. All grounded well. I might also get some Cuban stations at times but they are buried in the noise.
Many of these stations are from Eastern Europe and Asia, so I can understand why you don’t get much at your end of the world.
Absolutely ingenious!
a much cleaner solution than I first had imagined.
Me too 😊
Manuel carefully your engineering prowess is showing, from concept to fulfillment, a simple elegant solution.
Thanks 😊 got there with a little help from my friends
That’s a useable effective addition, where I have externally connected bulk hook ups.
MFJ-956 with a rotating loop antenna makes it interesting.
AOR LA400 has a lot of potential and flexibility too but the technology costs a fortune and is difficult to source these days.
I was the only AOR radio distributor in Australia just over 10 years ago. I couldn’t see it lasting so I stocked up on distributor pricing purchases, before business ceased.
Keep up the interesting tech ideas. I am still watching now and then between busy times.
👍
👍
What an excellent idea. I would have like to see how it actually works at the higher frequencies.
Genius, yet simple! 👌
Thanks
It's amazing what you can do with some imagination and a 3-d printer. Nice job!
Especially the printer 😊
I've made many shortwave fine tuning add-ons, from varicap diodes, to adding a small capacitor tuning condenser and adding a small capacitor in series with a large tuning condenser, like your experiment. All of these had to have a knob fitted to the front panel to control the bandspread. Your method certainly gets around that problem. Great job.
Thanks
Very clever solution, Manuel!
Thanks
That's clever!
Well Mr. C, that is just bonkers brilliant. I take my hat off to you. All the best mate.
Thank you
Brilliant!!! Doing this to my Grundig without a doubt. You could even fit another 10, 15 or 20pF cap in series, between the main tuning capacitor and that new variable capacitor, with a switch somewhere on the back that shorts it out for lower frequencies and is open for the higher frequency range to reduce it's capacitance accordingly.
👍
wonderful, 20pf is too much, place 5pf serial and you will squeeze the fine adjustment 😉👍
The bulgarian veneer furniture of my parents I'm still keeping has two concentric tuning knobs and the inscription on the dial glass says "tuning" and something that translates, i.e. into German as in this radio "UKW und KW Lupe" and works exactly this way (in fact, in Bulgarian magnifying glass sounds and spells in Cyrillic exactly as in Spanish and Portuguese).
That’s great to have the function already built in 👍
Nice work around 👍
👍
I was thinking of going Bluetooth to control a servo connected to a cap.
But your way will work as well 🙂
Yes, I first started thinking high-tech too
Extremely clever and non intrusive. Maybe place a adhesive label on the top of the upper plate if anybody ever wants to remove it? I don't see why they would if they know what it does. This is great work.
Thank you
I love the simplicity of this solution and as a Saba radio fan, bandspread was not something high on their agenda. I am going to take a peek at how this could be implemented on a Meersburg or Freiburg. I am guessing you had to work through some formulas to determine the right 3D print plate size (and gap too) to hit the capacitance range you achieved (and at the same time get it to fit within the contraints of the radio too). I am wonderig if that took a few kicks of the can to get right?!!! Without a doubt, a very impressive result!
Actually, the first challenge was the fit, with no calculations at all. The separation was achieved by trial and error - the closer the plates, the higher the C. You really only need a small capacitance so it’s not difficult.
@@electronicsoldandnew Interesting! Thank you for that insight. Very helpful to know. Much appreciated! 🙂
Pleasure
Genius 👏👏👏😀
Thanks 👍
A very elegant and reversible solution Manuel. With hindsight it's surprising that the manufacturers didn't do something similar as standard when they had a "rotatable ferret" in the cabinet. 🤣 But with the additional capacitance now controlled by the ferrite rotation (unless you can find a pair of spare contacts on the SW pushbutton switch to only add it for SW) are you seeing an unacceptable interaction between the ferrite rotation and MW and LW station tuning? Not that we have much on either band these days worth listening to so only an issue for those not using an external antenna maybe?
The small amount of extra capacitance won’t have any noticeable effect on MW or LW. I’ve tested it and it really negligible
@@electronicsoldandnew Fantastic. If it had been an issue then just connect the capacitor controlled by the ferret to the SW oscillator coil padder capacitor instead as I assume that's switched out when SW isn't in use?
True😀
Some radios allow you to fine tune the SW by turning the FM knob, called “short wave log” on my Opus 7. Have you ever explained how that works in any of your videos? If not, perhaps you can describe how that functions in a future video. Thanks
I have, but can’t remember in which one 😊
also connect this fine condenser circuit not to main tuning condenser, but to KW coil, so it will work only on KW, otherwise it will influence the turning of MW when rotating FA!
Yes, that would be best. However, the effect on MW and LW is negligible, I tested it.
Who would think of a thing like that? Only M. Caldeira!!
This is common problem with many radios where SW is in one band in range 6-12 or even 6-16 MHz. But only few radios have this ferrite rod seting.
True. This is definitely only applicable for some sets. I’m sure alternative solutions are just waiting to be found for the others.
@@electronicsoldandnew In some tube sets with split AM/FM tuning, FM tuning was used for this.
In transistor radio maybe varicap controlled by voltage from tone control potentiometer should be added.
👍