Thanks, good to hear that. I will draw the schematic asap. Can take some time, anyway. 3 June 2024.

Zeer bedankt voor je reactie! Kijk vaak naar je video's, ze zijn voor mij heel leerzaam. Ben zelf niet met zulke hoge spanningen en stromen in de weer... Enfin, het is (ook) je werk...zo heb ik begrepen. Ja, de zomer komt er hier aan. De lente was hier vrij koud en nat, afgezien van een paar mooie dagen. Ik ga ervan uit dat het gaat doorschieten, de komende maanden. Groet, Ko, bedankt. 2 juni 2024.

Thanks Ron and also thanks about the older gardening video's that I posted. 2 June 2024.

Thanks for your reaction, much appreciated. Obrigado pela sua reação, muito apreciada.

Thanks, good to hear that. Gardening is always an "adventure", every year.

Hi I don't know exactly what you mean. What is SAQ? Where (on which frequency) does it transmit and/or in which country or countries? What is the modulation: AM/FM/SSB or SSB derivates? What is the energy sent out on (a) or that VLF frequency? And: what is the way via which you want to receive that frequency: TRF, Superhet or heterodyne? Thanks. 2 June 2024.

Thanks Ron, yes I took a deep dive into radio coils, now and in the past, say during the past 20 years. Thanks that you could use these insights, hope everyone interested in "the radio" can use them too. 2 June 2024.

Thanks, took some time say more time.

Thanks, good to hear that. And I will surely go on. Obrigado, é bom ouvir isso. E certamente continuarei. 2 june 2024.

Thanks, good to hear that.

That is an idea....

Great advice and thankyou for sharing.

@@radiofun232definitely could sell them.

Thanks, good to hear that 😁

Thanks & yes, it is more or less the common way to get good results.

Thanks! best regards 27 May 2024

Please read my reaction to tonychristoph1063 where everything is explained.

You can try it.

I want to make a superhet for frequencies between 150 KC and 300 KC with a 465 KC IF frequency. And of course: it is the pleasure of experimenting. 😁

OK, thanks, no problem. I am always interested in electronic circuits from radio amateurs or anyone publishing something on KZbin in the field of electronics, as broad as it is: audio, digital, radio, etc. 25 May 2024.

Why don't you do that and show it on your YT channel? Everyone can take profit of that.

thanks, good to hear that.

thanks

Thanks Barry, yes, you saw that OK. It is always a (kind of, not really) problem where and how to mount these (or any) VLF coil(s) inside these simple 1 transistor oscillator(s). The good thing is that long ("long"?) wiring is no issue here, because we are on VLF, say between 100 KC and 600 KC. Thus, indeed, connecting/changing/interchanging all kinds of VLF coils in this way is very easy and good to do (!). 24 May 2024.

Thanks Ron. Yes the idea now is to use/make a Local Oscillator in a superhet circuit via up-mixing, when receiving frequencies on VLF/Long Wave. That principle (up mixing frequency transformation) worked always in all my SW radios, say 2 MC-14 MC that I made in the past.The down-mixing idea for VLF did not work so well, though the radio theory shows that it is/was/could be possible. I did not elaborate that to its depth, b.t.w. Above 2 MC the making of a superhet radio is easy, below 1 MC I am struggling. Has of course to do with the problems related to LW, say the properties of these long wave frequencies. Anyway: it is always interesting and it is a hobby (!). 24 May 2024.

That is/was a very interesting issue! Could also have been an effect on the ferrite antenna or one of the coils, by the way. Anyway, thanks, this is very important info for everyone.

Hi Glasslinger, it means NanoFarad. It is more or less common in Dutch electronics magazines. So 1 N = 1000 PF.

Good idea!

Inter-plate distance would be too great to make anything of more than few pF I would guess. And there's the inner foil to worry about. I'd be curios to see if that has much effect actually. Unless you made the dielectric of something very thin and put a layer of aluminium on as the conductor. Greaseproof paper would work, saran wrap/cling film would be fantastic. Or go all old school and make it out of PCB! Oh I wish I was young and rich. Then I wouldn't waste all my time learning this stuff and I'd move somewhere hot with lots of alchol.

@@marcdraco2189 My idea is to encase the CD in tape so both sides are electrically one surface. Then sandwich several CDs like an old school variable capacitor found in tuners. One set of CDs on a shaft. Another set as fixed vanes.

@@acestudioscouk-Ace-G0ACE gotcha. Just keep in mind the distance between the conductors (the thickness of the dielectric makes a huge difference. Air gap capacitors use multiple plates with minute spacing between each to manage just a few 10s of picofarads. The perfect dialectic would have infinite resistance and be infinitely thin. I’m fond of air gap caps but the modern nasty plastic ones pack as much capacitance into a tiny plastic box and don’t break down when they pick up the inevitable dust and dirt offer years of us. Remember the charge is due to negative charge carriers one plate and positive ones on the other. The weak force pulls them together so they get “stuck”. The larger the distance the weaker the attention. The large area is required to give more area for the charges to spread across. But If the gap is too large the charge has nothing to keep it in place. Tiny capacitors can’t hold change for very long but at radio frequencies they don’t have to. It’s impressive to think that a modem capacitor can hold a surprisingly large amount of energy on its plates, when the same amount of energy stored in a magnet field takes fairly chunky inductor. And, of course the field collapses as soon as the power is removed.

@@marcdraco2189 Thanks for your reply and information. It's an experiment I'll get round to one day when time permits. At present my time is taken up with antenna and shack building. 73

As far as I know: no. But when you study old school radio books, the way that the capacitor changes its capacitance when the knob is turned can differ substantially. Has to do with the way the plates are made, thus say making a linear change of the capacitance or a non-linear change. Has to do with the frequency band for which they are/were made (in the past) and say the "spread" of the received radio signals on the tuning scale, given a certain frequency band. 22 May 2024.

Hope that it could help.

@@radiofun232 sure Ko....try to present a type of oscillator using those caps

@@SeAfasia Yes, I have the schematic already, also in other video's on my YT Channel btw. But there will surely be a new experiment for a VLF oscillator in the coming days. 22 May 2024.

Yes & true, these old school ones.

Old tubes radio have this types tunning capacitor . Plastic ones come with transistor radio with Japan made one . Good job

You mean the geared air-gap ones? Like rocking horse droppings mixed with unicorn hair. The plastic nasties are still widely available.

@@marcdraco2189 Yes, though there are/could be quality plastics, though (of course) never used in these old school tuning capacitors of the 1940's-1970's, early 1980's, like I show here, where the isolation material was HQ porcelain.

I posted a first comment on your reaction, though could not see it afterwards. As far as I know, where porcelain is used to insulate the capacitor plates, we have to do with (quite) high quality tuning capacitors, in general made for tube circuits or anyway. In (say) "modern" tuning caps (say the small ones for transistor radio's) we have to do with certain plastics that insulate the capacitor plates, going from say 10 to 150 pF or 10 to 470 pF (in general). These plastics insulate quite good and thus they were able to make a small tuning capacitor in a very small size, like you see them here. That is what I wanted to tell when making this video. 24 May 2024.

Hi, thanks for your comment. Though the issue is more or less the same, I had no computer circuits or digital IC's in mind when making this video, only audio and radio circuits. And yes, computer chips are often decoupled directly from their V pin to ground. The setup with a series resistor to the voltage pin of IC's is not often seen there. The decoupling setup between computer chips and radio or audio circuits differs, because digital chips manage digital signals, say squarewaves. Digital signals/squarewaves have a lot of harmonics, that is why they use such a heavy way of decoupling (often each chip gets its own decoupling capacitor). Other thing is that computer chips must switch quick, a R-C combi in their power leads can make them sly. They must be able to switch sharp pulses with (say) current peaks. The idea of this video with a focus on audio and radio is this: a hum free (regulated or not) power supply (via a transistor or a chip from the 78XX family) supplies each electronic unit via a resistor (value depends on the current that the unit needs), and each unit gets its own electrolytic capacitor (minimum 10 uF), bridged by a non-polar cap (say 100N) and a high value resistor (say 470 K). That is the idea that always works nice for audio and HF pre-amps, IF amplifiers, etc. In general not the way that digital chips are decoupled. 21 May 2024.

@@radiofun232 Thank you, for your excellent explanation and reply. This video contains very good information. Bravo!

You are welcome. It is one of the keys to success in home brew electronics.

OK, thanks.

Thanks Ron, good to hear that.

Yes, the understanding of principles first. It's hard to calculate the capacity if one has no clue about the basics.

Yes, surely, always. Much more info in tens of other video's on my YT Channel. You can search there via my channel trailer "Radiofun232 on KZbin", via the looking glass (search option) when you type there keywords like "IF, IF amplifier, radio, radio technology, shortwave, filter, wobbulator", etc. What you adress is a common comment of viewers when they are looking at my filter schematics, both for audio and HF (radio applications). The input-and output impedance and the effects of that on the bandwidth, here say 10 KC or 8 KC in a radio application (superhet). I have payed, many times, attention to the question that you propose and that is a right question, by the way. But, anyway, this video is also OK in this regard. It shows if a ceramic filter in the 455 KC order is healthy, thus usable in a IF amplifier, of whatever kind (FET, BJT). Of course, in all cases, all IF filters amplifiers in a superhet. radio IF amp. must be tuned, so that the IF amp. has a proper bandwidth. More info in the video's on my YT Channel. Thanks 20 May 2024.

Look at his test circuit. Its output goes to a frequency counter of 50 ohm input.

Yes, I know that issue. Like you know, you told it, I have, once, published a schematic of a simple FM radio with the TBA 120 IF amplifier and FM detector chip. Video link kzbin.info/www/bejne/fGbamaClesiVpJI I think that is all that I can say about making a simple FM radio between (say) 88 MC and 110 MC. Of course it needs a ratio detector (FM detector), but everything is showed in that video. Thanks. Many video's about how a FM detector works are on YT. 20 May 2024.

All info is (earlier video's about FM/TBA 120 etc) is in links in the description of the named vid. Its video link is here kzbin.info/www/bejne/fGbamaClesiVpJI 20 May 2024

Hi, many thanks! Very informative for me.

Thanks Steve!

Thanks, and yes that is an issue. After every experiment I clean up the workbench and all the components go back on stock.

True. Thanks Barry.

Thanks Ron.

Yes, it is possible, when you connect the ceramic filter (say 455 KC) at the output of the test oscillator, at the same time connect a 455 KC coil filter at the input of the test oscillator. Scope + counter to the output. When the coil filter is tuned (by moving the core in-out) you can see where the best resonance peak is. Thanks. 19 May 2024.

More info here kzbin.info/www/bejne/hmTdq6icbtVrnqssi=5nr39s1gdRC893M1