In my receiver, I am at the moment, using a CMOS 4024 IC.

After research, I think that switching to a counter in a 74HCT IC is better, provided that I change my voltage.

I don't know the best class to use.

What I have learned from experience is that the 74LS series tend to burn out easier.

so can someone list me in order of maximum voltage, followed by maximum speed which IC family I should use?

I'm willing to buy another counter IC. I would like the receiver to run on 9V as well, so any IC that works with 9V will be great.

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-=: The best low-priced components to troubleshoot with are the speaker and the LED :=-

 

maybe this would be helpful to you

http://www.electro-tech-online.com/v...?p=95492#95492

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Beginner's Guide to Microcontrollers

 

I thought it was a transmitter that you were trying to tune with the counter.

The problem of using a counter in your circuit will continue with any other logic family. A counter's outputs have logic level voltage changes, not switches.
When a counter output is high, its "tuning capacitor" is connected across your inductor, if the wires are short enough.
When the same counter output is low, then its tuning capacitor is still across your inductor because the supply has a low impedance filter cap to ground.
Therefore the capacitance across the inductor doesn't change when the counter's outputs change. Threrefore the tuning doesn't change.

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Uncle $crooge

 

All chips beginning with 74 have 5V supply voltage except 74HC series which can be supplied with 6V.
CMOS 4000 series can be supplied with maximum of 15V.
I think you know it.
Once I met high voltage TTL chips that had 15V supply but it was some 30 years ago.

 

74HC series ICs are guaranteed to work with a supply voltage as low as 2.0V so I used them in my 3V Ultra-bright Chaser project where the battery voltage drops to 2V over its long life.

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Uncle $crooge

 

You and with hte added noise margin of HC logic they are always my first choice

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Nothing is impossible.
Once a problem is realised, the rest is just details

 

huh... :lol:

 

It's actually both transmitter and receiver. One of these days, I'll turn it into a self-tuning packet radio modem :idea:

Does this apply to all IC families? because some of them require inputs to be either tied to a pull-up resistor or a pull-down resistor. and what IC family requires outputs to be tied to pull-up or pull down resistors? because that's the family I want to try to avoid.

Here's my theory

Attached Images

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-=: The best low-priced components to troubleshoot with are the speaker and the LED :=-

 

The 74Cxxx series, like the 4000-series, can be operated as high as 15v on the power supply rails. TTL for 15v power supply? I don't think so. The "high voltage" operation you may be thinking of was for display drivers and open-collector logic where you could use higher voltages, sometimes even driving Nixie tubes in some cases.

74LS "burns out" so easily? TTL and ECL is probably the most durable of all the logic families. You want easy to destroy? Try using the old 4000A series vs. the 4000B series. Wow. Look at it cross-eyed and ESD zapped it because it had no internal protection.

The BEST logic family? By far, it's 74xxx, 74Lxxx, 74Sxxx, 74LSxxx and 74Hxxx. Why? Because it's what I have the most of. Probably on the order of 2000-4000 chips available. So, it's the best because I can build nearly anything for next to zero cost. I don't have to run out and buy the latest PIC or µP or odd-ball logic family to build a circuit. Yes, the digital stopwatch, digital clock, frequency counter or other logic circuit I build will require a lot more chips, use more power, take up more space, be more difficult to build, etc., but it won't likely cost me a dime for parts. And I'll also know the circuitry a lot more intimately that I would with an LSI equivalent.

Dean

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Dean Huster, Electronics Curmudgeon
Contributing Editor emeritus, "Q & A", of the former "Poptronics" magazine (formerly "Popular Electronics" and "Electronics Now" magazines).

R.I.P.

 

No counter has output on-off switches. Transistors can be used as switches but their output capacitance might be equal to the capacitors you want to switch off.

The capacitor and inductor are never in series because the positive supply and ground are at the same RF potential. The capacitor is always connected in parallel with the coil.
We wish you would understand this.

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Uncle $crooge

 

Each logic family has some good point and suffers somewhere else.

For speed to power dessipation LS is the optimum.

Often speed and (power dessipation and voltage levels) are inversely proportional.

The datasheet of CMOS ICs specify the maximum switching speed with a Vcc specification. If the Vcc is kept at maximum allowed voltage, the speed the max.

And the power desipation is specified at minimum voltage. :?

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Bharath Bhushan Lohray.
M.Sc. Electronics.

 

I've been seeing this go on in so many threads, I feel I need to chime in too.

Audioguru is right. one of the first thing they teach you in dealing with AC signal analysis is that DC VOLTAGE SOURCES ARE AC GROUNDS! when you look at a circuit in terms of AC signals (like radio signals), VCC and ground are considered the same point, because VCC is a DC voltage, and has no AC content. so literally, take your little diagram, cross out VCC, and draw a ground symbol there, and maybe then you can see why the capacitor is in parallel with the inductor in both cases!

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EEgeek.net

 

I hate to break the bad news to you, but I never learned AC circuitry in school, yet I am able to pull off several working circuits.

I have a problem with that. If I make VCC equal to ground, AC or DC, then I'm creating a hot, and possibly exploding battery.

To me, AC means alternating current. where the two rails consistantly change polarity. The capacitor is useful for holding the voltage, and I think it is what is actually causing VCC and ground to be equal.

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-=: The best low-priced components to troubleshoot with are the speaker and the LED :=-

 

Don't connect VCC to ground in your circuit with a wire, connect them on paper and LOOK at it. The supply bypass cap does it at the RF frequency that has low power, and makes the tuning cap in parallel with the inductor so their small RF current can alternate between them.

Mains rails alternate the polarities of the voltage and current. But most electronic circuits use a single supply so their rails are a fixed DC voltage (without any signal) and ground. Oscillation in a single supply circuit is AC voltage and current that don't alternate polarities, they just increase and decrease in level.

The supply bypass capacitor, correct. That's what it is for.

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Uncle $crooge

 

LMAO. :lol: :lol: :lol:

I didn't say I was going to do it. I'm sure an electronics novice knows not to do that, right?

Looks like I found an answer to my question: no supply cap!

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-=: The best low-priced components to troubleshoot with are the speaker and the LED :=-