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The HT9170 DTMF has a voltage range from 2.5V-5.5V its a cmos version of the 8870.Its a clone,with a wider voltage range.
Plus i use single AA cells that are 3.6-3.7 volts for my projects.I don't need to buy whole bunch of batteries for 5V.
And they last alot long.At 2400mAH at 100mA or less.I...
I have chaged the 10K to a 20K pot for variable gain
increased the biasing values to 100K.Is that enough.
Added the 10uf cap on the supply pins.
For CC1 isn't 100uf to big what if i use 1000pf. would the larger cap filter out
the lower FQ.
Enclosed changed circuit.
Do i need to add a cap or...
Left click this image.
Enclosed is the amp.
Do i have this amp design correctly.If not.what do i need to omit or add
to the circuit. for this to work correctly for my project.
Then how do i connect it to the HT9170.In post #1,image.:-?
The reason for the non-inverting the mic has a high impedance.And if it in the inverting configuration which has a low inpedence of 1K
it will attenuate.This is what i found out.
The crystal is a 3.5795mhz I'm using it is the correct one.
Can you help.
The attachment open for me click on the...
Hi all
Having trouble configuring this op-amp in my project.And get it to work correctly.
**broken link removed**
Using op-amp LMV796 from TI.
In a Non-inverting configuration.And it must be in the Non-inverting configuration
So the signal does not attenuate from the electret Mic.
The...
ljcox
I'm still not understanding the 4520 ics.
I'm ordering the parts.
once i start building the circuit i will need to put an LED at each stage
maybe this will make sence on the functioning of each stage as i go.
I will contact you when i start constucting the circuit.
I do appreciate...
ljcox
Ok. I took another look at the waveform. as you suggested.
Yes! I understand Q19 has a total waveform of 16sec period. 8secs (on) 8secs (0ff).
So the LED will come (on) for 8secs high,and then go's (off) for 8secs low.Right! This i understand.
What i do not know :-?. Is the 524288bit...
So. If i were to put an LED on Q19 it will take about (4 hours) for 262144 pulses high and another (4 hours) for 262144 low before the LED gos high and turns on at 524288bit. Is this right!
kerim
I'm Ebonic...Not Len. Isn't Len ljcox? His first name is Len.Im assuming.Away.
I wrote post # 43 for ljcox who is. Len!
I wrote in post # 51. Then i reposted post #43 in a reply But? It some how posted in #51.Sorry.
Did you write post #50 for me. If you did.Then my answer is. No! I...
Kerim
Should i use all diodes on the output and one resistor
or use 4 doides and one resistor as to what Len suggested.
It should be 9Hours ON 15Hours OFF. Turning on 8:30AM thur 5:30PM. Then OFF 5:30PM thur 8:30AM.
You have it 15Hours ON 9Hours OFF.Or did you write it backwards.
Can you...
KerimF
It should be 9Hours ON 15Hours OFF. Turning on 8:30AM thur 5:30PM. Then OFF 5:30PM thur 8:30AM.
You have it 15Hours ON 9Hours OFF.Or did you write it backwards.
Can you please! Explain to me. How your circuit is to function.
Thanks
KerimF
Thanks for you input and circuit
I will look into try this out.
I will get back to you.
Appreciate your help.
I still work on the circuit and try to understand what ljcox make for me.
I'm waiting to here from Len to respond to post #43
ljcox
This is what i think? How this timer circiut is functioning. But? I still may, not be right.
The crystal resonates at 32.768khz. It pluses 8secs on 8sec off. For a period wavefrom of 16sec total.
With an output FQ of 0.00625Hz. So. U1 is the timing clock for the circuit.
If you take...
ljcox
I need to ask you about the block diagram in post # 23
I really need to understand this diagram before i begin
to construct the circuit. Please Help?
The 32.768khz crystal. Is that the FQ its resonating at
And the passive compoenets are calculated for this crystal.So it can work at that...
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