The PMT in control of the Devil

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Re: The PMT in control of the Devil

Postby Steve Anderson » Fri Jul 21, 2017 1:55 pm

Yes, they look generic copies of the DAC-08 and the other flavours of it, so they should work fine.

Well done finding the datasheets, even in Russian you usually can 'decode' them, it's not a novel.

I'll PM my address...

Steve A.
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Re: The PMT in control of the Devil

Postby Harry Dalek » Fri Jul 21, 2017 2:28 pm

Steve Anderson wrote:Yes, they look generic copies of the DAC-08 and the other flavours of it, so they should work fine.

Well done finding the datasheets, even in Russian you usually can 'decode' them, it's not a novel.

I'll PM my address...

Steve A.


OK thats out of the way just have to wait for them to turn up ! have Pm you .
data sheet had schematics and i noticed the internal resistors that looked good to me !
Looking again at the idea here the 4060 still has to go 4040 direct to the DAC input pins thats me speculating ! if theres a better idea for the clock ic or in between ic connecting to the ADC chip do mention it as i can get what ever now .
So if i am keeping the 4060 need to increase the 4060 clock frequency ...now we can still go R/C but is a crystal oscillator version of this circuit now more logical ? either way comes down to what the clock frequency has to be and give a number of different line rates at the ADC sawtooth circuit if i have got it right .
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 PMT in control of the Devil

Postby Steve Anderson » Fri Jul 21, 2017 3:52 pm

The problem with the 4060 is that it doesn't have eight adjacent flip-flop outputs available because Q10 is missing. Also the oscillator needs to run at much higher frequency due to Q0, Q1 and Q2 also being missing. The 'HC4040 is a much better bet having all 12 outputs available. It of course needs a separate oscillator but that's easy with a good old 555.

A note on the DAC-08 (or whatever), although you may run it off +/-12V supplies, the inputs are 5/3.3V compatible. Pin 1 determines what voltage the internal logic switches at. With pin 1 grounded it switches at 1.4V (two diode drops), so it interfaces perfectly with 5/3.3V logic. If you were using 12V logic you would apply about 4.6V to pin 1 making the switching voltage 6V. A very useful feature. Here you just ground pin 1 (as I have done).

I need to sketch up the changes for this timebase use so don't go building anything yet.

Steve A.

Forget the 555 idea...I may have a simpler and more flexible solution. Be aware that here I'm still thinking in terms of powers of 2, i.e. 32/64/128/256 lines. Anything else adds complexity.
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Re: The PMT in control of the Devil

Postby Harry Dalek » Fri Jul 21, 2017 7:22 pm

Steve Anderson wrote:The problem with the 4060 is that it doesn't have eight adjacent flip-flop outputs available because Q10 is missing. Also the oscillator needs to run at much higher frequency due to Q0, Q1 and Q2 also being missing. The 'HC4040 is a much better bet having all 12 outputs available. It of course needs a separate oscillator but that's easy with a good old 555.


Thanks there it points me to what i should use here in this reboot ..i like the 555 apart for frequency drift if the voltage isn't regulated just about make a good VCO .
So OK the 4060 out 555 back in .


A note on the DAC-08 (or whatever), although you may run it off +/-12V supplies, the inputs are 5/3.3V compatible. Pin 1 determines what voltage the internal logic switches at. With pin 1 grounded it switches at 1.4V (two diode drops), so it interfaces perfectly with 5/3.3V logic. If you were using 12V logic you would apply about 4.6V to pin 1 making the switching voltage 6V. A very useful feature. Here you just ground pin 1 (as I have done).


Dual 12 volt supply is fine then looking at your schematic i looked pin 1 is grounded so the DAC are all about the same here ...that reminds me have to order some 7812 7912 regulators always run out of those .

I need to sketch up the changes for this timebase use so don't go building anything yet.

Steve A.


OK 3rd time lucky i will wait :wink:

Forget the 555 idea...I may have a simpler and more flexible solution. Be aware that here I'm still thinking in terms of powers of 2, i.e. 32/64/128/256 lines. Anything else adds complexity.


OH alright ...i will see what you come up with ..power of 2 is fine ! very happy with that idea .
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Re: The PMT in control of the Devil

Postby Steve Anderson » Fri Jul 21, 2017 9:01 pm

With the combinations of line quantity and frame rate you'll be needing the slowest, i.e. 32-lines at 12.5Hz, 400Hz line-rate, up to 256-lines at 50Hz, 12.8kHz...and all those e in between. Not a huge amount and quite do-able. 12.8kHz, 6.4kHz, 3.2kHz, 1.6kHz, 800Hz and 400Hz. You've generated them all already! Plus the three frame rates of 12.5. 25 and 50Hz.

What we're doing here is taking on a suitable and consistent ramp generator whose amplitude remains the same whatever the combinations are. So no twiddling of knobs or flicking switches to fill the screen. Being potentially a mechanical source of video I've shied away from the crystal idea as you will need the the ability to match the slight 'off'' rates sometimes encountered.

Now 256-bits at 12.8kHz requires a clock rate of 3.3MHz approximately, a 555 isn't really up to that. So I'm considering the VCO section of a 4046 for this, such you can adjust the clock say +/-10%, maybe +/-20%. The rest of the 4046 would be unused.

This obviously is not locked to the incoming video, that's where the MR line(s) come in.

More as I think on this....

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Re: The PMT in control of the Devil

Postby Harry Dalek » Fri Jul 21, 2017 10:16 pm

Steve Anderson wrote:With the combinations of line quantity and frame rate you'll be needing the slowest, i.e. 32-lines at 12.5Hz, 400Hz line-rate, up to 256-lines at 50Hz, 12.8kHz...and all those e in between. Not a huge amount and quite do-able. 12.8kHz, 6.4kHz, 3.2kHz, 1.6kHz, 800Hz and 400Hz. You've generated them all already! Plus the three frame rates of 12.5. 25 and 50Hz.


Yes all that looks familiar for sure .


What we're doing here is taking on a suitable and consistent ramp generator whose amplitude remains the same whatever the combinations are. So no twiddling of knobs or flicking switches to fill the screen. Being potentially a mechanical source of video I've shied away from the crystal idea as you will need the the ability to match the slight 'off'' rates sometimes encountered.


OK i can understand that with the crystal idea it does have the stability but not the flexibility .

Now 256-bits at 12.8kHz requires a clock rate of 3.3MHz approximately, a 555 isn't really up to that. So I'm considering the VCO section of a 4046 for this, such you can adjust the clock say +/-10%, maybe +/-20%. The rest of the 4046 would be unused.


OH The 4046 can go that high is there a version that chip that is better or any is fine ? bit like using it for SSTV to swing between black and white frequencies but one high fixed frequency i think your meaning to use it for .

This obviously is not locked to the incoming video, that's where the MR line(s) come in.

More as I think on this....

Steve A.
[/quote]

MR lines Sorry Steve ?
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Re: The PMT in control of the Devil

Postby Steve Anderson » Sat Jul 22, 2017 12:02 pm

Harry Dalek wrote:MR lines Sorry Steve ?

MR - Master Reset input to the 4040(s), pin 11. At first just to test the whole thing out these will be at 0V, later they'll be driven by sync pulses resetting the counters to start of line/frame.

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Re: The PMT in control of the Devil

Postby Harry Dalek » Sat Jul 22, 2017 12:50 pm

Steve Anderson wrote:
Harry Dalek wrote:MR lines Sorry Steve ?

MR - Master Reset input to the 4040(s), pin 11. At first just to test the whole thing out these will be at 0V, later they'll be driven by sync pulses resetting the counters to start of line/frame.

Steve A.


OH yes it was the main reason i went with a 4060 so i didn't have to worry about the framing problem i can see here it needs to be worked out ... have to remember as well to order another 4040 unless i have another one handy .
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 PMT in control of the Devil

Postby Steve Anderson » Sat Jul 22, 2017 6:47 pm

You might be needing more than one additional 4040, I suggest you order 4, they're always useful to have around. I think this will require a total of three 4040s.

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Re: The PMT in control of the Devil

Postby Harry Dalek » Sat Jul 22, 2017 7:42 pm

Steve Anderson wrote:You might be needing more than one additional 4040, I suggest you order 4, they're always useful to have around. I think this will require a total of three 4040s.

Steve A.


Thats good to know thanks i will put those on the list and get some spares...I was also looking at the top range of the VCO in the 4046 the cd version is just over a 1mhz and 15MHz in the 74HC4046 i think i just have the first version just in case ..
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 PMT in control of the Devil

Postby Steve Anderson » Sat Jul 22, 2017 8:01 pm

Because of the speeds involved this all has to be HC, CD/HEF is way too slow even when used at 12V, at 5V it's positively sloth-like. I really don't understand why people still use it.

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Re: The PMT in control of the Devil

Postby Harry Dalek » Sat Jul 22, 2017 8:47 pm

Steve Anderson wrote:Because of the speeds involved this all has to be HC, CD/HEF is way too slow even when used at 12V, at 5V it's positively sloth-like. I really don't understand why people still use it.

Steve A.


I grabbed i think the CD type cheap they were but i had nothing but trouble with them again i will have to double check if i have the HC ..glad i looked !
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 PMT in control of the Devil

Postby ppppenguin » Sun Jul 23, 2017 3:55 am

A warning that different makes of of 74HC/74HCT logic can give different results. Ordinary logic is generally OK but anything vaguely analogue is not. Such as the 74HC4046 phaselock and 74HC221 monostables. It's some years since I did the experiments but the best I've found are Philips. Their HC4046 and HCT4046 will work reliably up to 27MHz. Other makes are lucky to get to 20MHz. Philips '221 monostables are also the most consistent I've found, especially for short delays. By contrast LS221 monostables are pretty consistent across all makes.

Much less difference than with 4046 and 221 but again Philips analogue switches (HC4053 etc) are the best for low crosstalk and flat frequency response.

Original 4000 series CMOS still has its uses for low speed work, especially as it will work up to at least 15V for those occasions where this is useful.

If your design needs more than a minimal amount of logic then you should probably be using programmable logic of some kind. Much easier than soldering together a load of CMOS or TTL. It also makes it easy to design decent synchronous logic that you can guarantee will work as designed.
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Re: The PMT in control of the Devil

Postby Steve Anderson » Sun Jul 23, 2017 1:12 pm

I have found the same in terms of speed variations between manufacturers, including HC logic. I have two bunches of 74HC4046s here, one batch from Philips/NXP, the other Fairchild. The Philips/NXP versions with work quite happily up to 25 or so MHz, the Fairchild versions, you're lucky to get 10MHz.

The interesting thing is this agrees with their respective datasheets, the implication is that not all chips of a certain species are created equal.

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Re: The PMT in control of the Devil

Postby Harry Dalek » Sun Jul 23, 2017 1:40 pm

Steve Anderson wrote:I have found the same in terms of speed variations between manufacturers, including HC logic. I have two bunches of 74HC4046s here, one batch from Philips/NXP, the other Fairchild. The Philips/NXP versions with work quite happily up to 25 or so MHz, the Fairchild versions, you're lucky to get 10MHz.

The interesting thing is this agrees with their respective datasheets, the implication is that not all chips of a certain species are created equal.

Steve A.

Thanks jeff and Steve here for the info .
Steve this sounds like its worth it
NXP HEF4046BP purchased in error.
This listing is for 10 pcs.
CMOS phase locked loop, voltage controlled oscillator, DIP16 package.
Free shipping.
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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