The Beast

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Re: The Beast

Postby Harry Dalek » Sun Jul 25, 2021 3:39 pm

BTW i know i have gone at little off track on this topic but it has its reason brain storm a way to feed higher video bandwidths to your multi system monitor or record from camera i suppose as well .
I was wondering how it would go looking into some thing like this ?

https://duino4projects.com/arduino-proj ... -recorder/

What would its top range be if you pushed the idea ?
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Sun Jul 25, 2021 6:04 pm

OK...lift up one end of R12 (22k), set POT1 to mid-way, set POT2 such that the wiper is at the end connected to pin 7 of IC2B, All being well you should have a nice sine-wave on pin 1 of the TL082 (IC2A) across the frequency range. Make sure the scope input is in DC-coupled mode (x10 on the probe as well) and the trace should move up and down the screen as you move POT1 from one end to the other. Set it so the waveform is equal pos and neg.

If all OK so far re-fit R12, don't touch POT1 again. Don't touch the scope at all, move probe to pin 7, disconnect any wires connected to this output...only the PCB, POT2 and the probe. Power-up and slowly rotate POT2. At first you'll see almost nothing, slowly a sine-wave should appear. If you can set it to 5V peak-to-peak...and leave it there. Check how it is over the frequency range.

If all OK add a 47 Ohm resistor on the board between pin 7 of the TL082 and pin1 of the connector labelled 'DDS', i.e. cut the track. Let's see if that helps...

I'm assuming you've already fitted the 100nF disc-ceramic caps I mentioned earlier, preferably right on the IC socket pins on the underside.

Steve A.

Not impressed by that recorder...forget it. Dismissive, yep, and I'm not going to explain why...except even more crap! Why not use the sound-card already in the PC - it's light-years better...

You could say much the same of my NBTV recorder, except in one respect that makes a difference with NBTV...sound-cards aren't DC-coupled and their LF point is somewhere between 10-30Hz. Really you could look at it as an application specific data logger...
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Re: The Beast

Postby Harry Dalek » Sun Jul 25, 2021 7:13 pm

Steve Anderson wrote:OK...lift up one end of R12 (22k), set POT1 to mid-way, set POT2 such that the wiper is at the end connected to pin 7 of IC2B, All being well you should have a nice sine-wave on pin 1 of the TL082 (IC2A) across the frequency range. Make sure the scope input is in DC-coupled mode (x10 on the probe as well) and the trace should move up and down the screen as you move POT1 from one end to the other. Set it so the waveform is equal pos and neg.

If all OK so far re-fit R12, don't touch POT1 again. Don't touch the scope at all, move probe to pin 7, disconnect any wires connected to this output...only the PCB, POT2 and the probe. Power-up and slowly rotate POT2. At first you'll see almost nothing, slowly a sine-wave should appear. If you can set it to 5V peak-to-peak...and leave it there. Check how it is over the frequency range.

If all OK add a 47 Ohm resistor on the board between pin 7 of the TL082 and pin1 of the connector labelled 'DDS', i.e. cut the track. Let's see if that helps...

I'm assuming you've already fitted the 100nF disc-ceramic caps I mentioned earlier, preferably right on the IC socket pins on the underside.

Steve A.


Thanks for the redesign Steve ! I am stuck with work next few days but i will take that one later in the week Thursday or Friday it would of be much easier if they designed this thing correctly in the first place ,Yes all the decoupling caps are under the board apart from one .
The pots in the design are shown as panel size they seem to be better once set to be left alone so better as trimmer size



Not impressed by that recorder...forget it. Dismissive, yep, and I'm not going to explain why...except even more crap! Why not use the sound-card already in the PC - it's light-years better...



Hahaaha :lol: i could see that one was no better or perhaps a touch worse than a pc sound card but never know unless you ask .Sounds like and external sound card is still a touch better so far .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Sun Jul 25, 2021 8:26 pm

Ah! I wasn't aware (or missed) the fact you'd extended the pots to off-board - that will not help either, that's adds stray capacitance just where it's not needed! Put the board back to original, though keep the 100n caps, the 47 ohm resistor and the TL082. Test it works as advertised.

I'll add suggestions to make it a bit more versatile later....

That audio 'thing' (recorder) is like a 20 year old mini compared to a brand new Jaguar...

Steve A.
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Re: The Beast

Postby Harry Dalek » Mon Jul 26, 2021 10:13 pm

Steve Anderson wrote:Ah! I wasn't aware (or missed) the fact you'd extended the pots to off-board - that will not help either, that's adds stray capacitance just where it's not needed! Put the board back to original, though keep the 100n caps, the 47 ohm resistor and the TL082. Test it works as advertised.


I did do that with pots via cables when i first cased it up now i just have some trimmers right on the board .it used normal sized pots but i have misplace the 50k pot so used trimmers
Ok i will not do that again with cabling .

'll add suggestions to make itI a bit more versatile later....


Thanks Steve see how i go later in the with with the instructions ...think i will draw it down to your changes so i have a little schematic before i hit the board .

That audio 'thing' (recorder) is like a 20 year old mini compared to a brand new Jaguar...

Steve A.

[/quote]

Yes i see what you mean .

Remember the last analogue tv recording device the DVR ? i think i still have one but without a remote ,i can only think that's a similar at least idea as computer recording to a Hard drive .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Harry Dalek » Thu Jul 29, 2021 10:42 am

Steve Anderson wrote:OK...lift up one end of R12 (22k), set POT1 to mid-way, set POT2 such that the wiper is at the end connected to pin 7 of IC2B, All being well you should have a nice sine-wave on pin 1 of the TL082 (IC2A) across the frequency range. Make sure the scope input is in DC-coupled mode (x10 on the probe as well) and the trace should move up and down the screen as you move POT1 from one end to the other.


Hi Steve i tried the above instructions getting a triangle wave out out of pin 1 no way near a sine wave at the higher frequency range .
probe on 10 x and Dc coupled .
And pot 1 the 1k pot moves the wave form up and down but right at one end of the wiper causes the scope to loose lock if that's any thing .

Set it so the waveform is equal pos and neg.
[/quote]

This i didn't understand Steve Sorry waveform looks equal

MMMMMMMMM not much to the circuit here perhaps the 2 100k resistor R21 R3 wrong values ?
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Harry Dalek » Thu Jul 29, 2021 4:51 pm

Ok putting aside the signal generator till further orders ; 0 ) i went onto finishing off The Beast today .
Once Upon a Time the case was a PC its very thick aluminium, the CRT a mid 60s oscilloscope the transformer from a 80s video disc player and various circuits boards i had used before for past projects laying around came in handy for this .
So its ended up another Vertical scanning monitor with a large syncing range from 18 line to 240 line range with 12.5 hz framing or 240 line with 1.5hz framing ran out of panel space for any other changes to the framing side so left this as is .
i can also via the panel switch in Steve's DA ramp generator here crystal generated so i have 3 frame rates 12.5 12 and 50 hz and line rates 16 line 32 64 128 256 512 1024 on 12.5hz framing which of cause drops the top line rate by half on 25hz framing half again on 50 hz so on
A slow drift on crystal sync only .

DSCN6471.JPG



The real Beast me !


Well as they say its never finished till the lids on and its on 8)
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DSCN6472.JPG
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Fri Jul 30, 2021 11:49 am

Harry Dalek wrote:....not much to the circuit here perhaps the 2 100k resistor R21 R3 wrong values ?

Nope, they're fine at 100k, they could both be 10k, it wouldn't matter, as long as roughly equal. I'm not sure what's going on here, there's something we're missing...though it could be hidden in the code...

Steve A.

Thinking on this a bit more...if the upper frequency is 65,000Hz or so, and the sine-wave is constructed from a look-up table of 256 values (a reasonable figure as it's an 8-bit D-A), that requires an update rate of over 16MHz, the crystal frequency is about the same (16MHz), I think the thing is running out of steam - all VERY rough figures...

It's probably good enough for rough checks up to around 10kHz, after that, you're on your own...

Steve A.
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Re: The Beast

Postby Harry Dalek » Fri Jul 30, 2021 3:07 pm

Steve Anderson wrote:Nope, they're fine at 100k, they could both be 10k, it wouldn't matter, as long as roughly equal. I'm not sure what's going on here, there's something we're missing...though it could be hidden in the code...


I did notice Steve it was fine giving a correct waveform on sinewave into that opamp all of its range as i showed a while back but not so for the other waveforms when on the higher range ,so that must be a problem with its programming ? i was only interested in the sinewave side of it at the higher range any way so that didn't bother me .

I could see swapping the crystal but what you are saying below it is what it is .

Thinking on this a bit more...if the upper frequency is 65,000Hz or so, and the sine-wave is constructed from a look-up table of 256 values (a reasonable figure as it's an 8-bit D-A), that requires an update rate of over 16MHz, the crystal frequency is about the same (16MHz), I think the thing is running out of steam - all VERY rough figures...

It's probably good enough for rough checks up to around 10kHz, after that, you're on your own...

Steve A.
[/quote]

If it were code i would think we would have a triangle waveform before the opamp so crap in crap out but its fine here so must be the opamp circuit or the coupling to the circuit well at the higher frequencies at least .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Fri Jul 30, 2021 6:34 pm

I simply think they're pushing things too far. Sure, 65-odd kHz no problem, but a sine-wave? Little chance, not absolute zero, but unlikely with what they're using here..

I'll work on my version that I started a while back over the next few days, it IS a sine-wave, up to 12.5MHz and down to a fraction of a Hertz. It doesn't have the fancy display, but do you need that when you have an oscilloscope? No, not really...nice, but not essential...though there's no reason you couldn't add what is essentially a frequency counter to it...which could be useful in its own right...

Steve A.

Jeez, more rain. it's been a wet year so far, I'm getting fed up with it! The joys of living in the tropics!!
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Re: The Beast

Postby Harry Dalek » Fri Jul 30, 2021 10:54 pm

Steve Anderson wrote:I simply think they're pushing things too far. Sure, 65-odd kHz no problem, but a sine-wave? Little chance, not absolute zero, but unlikely with what they're using here..

I'll work on my version that I started a while back over the next few days, it IS a sine-wave, up to 12.5MHz and down to a fraction of a Hertz. It doesn't have the fancy display, but do you need that when you have an oscilloscope? No, not really...nice, but not essential...though there's no reason you couldn't add what is essentially a frequency counter to it...which could be useful in its own right...

Steve A.

Jeez, more rain. it's been a wet year so far, I'm getting fed up with it! The joys of living in the tropics!!



I do have a pretty easy one but only Square wave i have used a bit .
download (1).png
download (1).png (74.16 KiB) Viewed 538 times

Yes display isn't necessary you have frequency meter on the digital scope .
Yes be good to see what you come up with it would be interesting to know how various sound cards act .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Sat Jul 31, 2021 12:07 pm

The oscillator I was thinking of is in the Off-Topic section, "A Useful General Purpose Oscillator.". It perhaps could do with some simplification...skip ahead to the last few posts...

That LTC1799 version is also ideal, except only square-wave output and 1kHz minimum frequency. add 2x74H390-type dividers to get down to 0.1Hz, but still only square-wave. For sine add an EEPROM, counter and a few other bits...actually there is another way to generate sine-waves..but it may require a filter on the output...a bit of a pain...it depends on how 'clean' you wish your sine-waves to be...

Steve A.
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Re: The Beast

Postby Harry Dalek » Sat Jul 31, 2021 4:16 pm

Steve Anderson wrote:The oscillator I was thinking of is in the Off-Topic section, "A Useful General Purpose Oscillator.". It perhaps could do with some simplification...skip ahead to the last few posts...

That LTC1799 version is also ideal, except only square-wave output and 1kHz minimum frequency. add 2x74H390-type dividers to get down to 0.1Hz, but still only square-wave. For sine add an EEPROM, counter and a few other bits...actually there is another way to generate sine-waves..but it may require a filter on the output...a bit of a pain...it depends on how 'clean' you wish your sine-waves to be...

Steve A.


Yes i had a look at the Oscillator your working on looks like a lot of thought went into this it is complex but no more really than that single generator i have .
I just did a software Test software oscillator to 20 khz and i can see the sine wave out of that lap top sound card up to 20khz on the scope so that's good does the minimum using that for the Beast monitor :wink:
Another ideas
https://www.amazon.com.au/Cubilux-Exter ... s9dHJ1ZQ==
I mentioned a while ago about the now old idea of dvd or HDD video recorders forgetting about the Video side as it seems these things can play back cds such so if you made say a 70 line video which would not play well via a pc sound card but it you recorded the wav video file to a cd or dvd and played it back on some thing like this device in the pdf it with play back 48 or 96khz video via its sound device ,well best i can work out... ? I Have this model but haven't used it for some time and no remote so no idea if it still works but looked up what it could do . But can most cd players or SD card players work at the higher sample rates these days ? or still behind some thing like this ?
I see it uses MP3 files WMA files not wav would it be a problem converting to those formats ?
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The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: The Beast

Postby Steve Anderson » Sat Jul 31, 2021 8:22 pm

Harry Dalek wrote:
Steve Anderson wrote:The oscillator I was thinking of is in the Off-Topic section, "A Useful General Purpose Oscillator.". It perhaps could do with some simplification...skip ahead to the last few posts...Steve A.


Yep, if you only need sine-waves It could be simplified significantly. After all, square waves are generally easy to generate. It's also all the peripheral stuff that makes it somewhat complex for what it is...as well as the PC interface...

Steve A.

There are also many on-line tone generators which generally will suffice for all we need here unless you need absolute frequency, levels and the lowest distortion...I can't see why for NBTV...sine. square, triangle, sawtooth....though generally only at audio frequencies your 'sound-card' can handle...

an example...https://onlinetonegenerator.com/

...also has 'maybe' useful other stuff too...
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Re: The Beast

Postby Harry Dalek » Sun Aug 01, 2021 11:24 am

Steve Anderson wrote:
Harry Dalek wrote:
Steve Anderson wrote:The oscillator I was thinking of is in the Off-Topic section, "A Useful General Purpose Oscillator.". It perhaps could do with some simplification...skip ahead to the last few posts...Steve A.


Yep, if you only need sine-waves It could be simplified significantly. After all, square waves are generally easy to generate. It's also all the peripheral stuff that makes it somewhat complex for what it is...as well as the PC interface...

Steve A.

There are also many on-line tone generators which generally will suffice for all we need here unless you need absolute frequency, levels and the lowest distortion...I can't see why for NBTV...sine. square, triangle, sawtooth....though generally only at audio frequencies your 'sound-card' can handle...

an example...https://onlinetonegenerator.com/

...also has 'maybe' useful other stuff too...


Yes the software is great up to 20 khz ,i was thinking this software VLF reciever can show at least what the sound card input can do
viewtopic.php?f=8&t=2329&hilit=vlf
down load at the top link gives various bandwidths you don't tend to get with a pc spectrum analyzer least would show what your sound card can handle in to it .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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