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You're close with this hardware solution. Don't give up now!
QuoteThat is correctly wired, but you need to use your 'scope on TP11 and TP12 and then touch the wire on TP13 to B+ to get the pulses. Vary the pot and touch TP13 to B+ again for a new pulse.You are looking for varying delays between the pulses on the two traces.Well I am at a dead stop! I have checked the wiring and switched out lm393's and still no readings that should be there.
That is correctly wired, but you need to use your 'scope on TP11 and TP12 and then touch the wire on TP13 to B+ to get the pulses. Vary the pot and touch TP13 to B+ again for a new pulse.You are looking for varying delays between the pulses on the two traces.
My fault entirely!Sorry about that, but I forgot to note down R8 as one of the resistors to include (from TP12 to B+).It has to be there, since the comparator, LM393, has got an open collector output, so it only pulls towards ground and need the pull up to show anything but low. Very sorry
Tell me whats next.
Next step is IC3 and surrounding components, up to (and including) TP15, but keep out R10 an onwards for now
Dual trace of TP12 and TP15 and still Using TP13 to B+ to make TP12 go low. And when I do this TP15 goes high at the same time.There is no lag time that I can see, both trace rise and fall at equal speeds.I know at some point a real signal has to be added, but just did this to see how the circuit was reacting!
There was a logical error, which your description, of TP15 going low when TP12 is (as it should go low when Reset), revealed to me
Dual trace of TP12 and TP15 and still Using TP13 to B+ to make TP12 go low. And when I do this TP15 goes high at the same time.
Here is what I am doing. Dual trace of TP12 and TP15 and still Using TP13 to B+ to make TP12 go low. And when I do this TP15 goes high at the same time.There is no lag time that I can see, both trace rise and fall at equal speeds.
So after you read this post please Tell me to continue with VER-2.0 or move along and update to Ver2.2
And Cussing was herd far and wide Well at least in my head
As at this point I am lost, SO what's New There is no inverting or time offset. and signal is strange @ SET and no signal @ RESET
I went back and checked the TP12 and it responded HIGH and low as TP13 was @ B+ and GND. Also I checked TP11 and it was making it 2ms rise signal /also when TP13 is @ B+ and removed from B+.
I wish I understood Transistors better, as I think that is where I lose the action of the circuit. I know that they are acting as switches as the gate voltage or current changes .
So let me ask and no laughing Here we go, Pin 10 of the mono-flop is going HIGH- LOW thats switching Q2 HIGH- LOW onto the base ofQ1. Q1 sends a high low pulse to IC1B pin6. IC1B has a ref voltage at pin5 that can fluctuate and when pin 6 of the IC1b starts going high. When it reaches a voltage level just above pin 5 of IC1b PIN 7 it in turn makes the signal High at TP12 to the pin 6 IC3B of the Flip-Flop? I just wanted you to hear where some of my confusion when trying to trace why the circuit is acting strange.
If you had only Flip and no Flop (sort of speaking), it would stay in the Flipped position
But!!!!!!! the circuit is so sensitive that anything applied to RESET pin 6 will trigger it and it will stay running. Tp12 does not have to be connected to the RESET for it to run. If I touch and leave a open wire to pin 6 of the IC3B it runs while it is connected. It is like the smallest bit of capacitance or inductance I don't know if it is either,triggers it and keeps it setting and resetting.
I hope I am making this clear enough. There is something wrong here I just don't know how to say it, correctly.I am very sorry!
It was working as I adjusted VRx1 making the Servo arm move back and forth. How happy was I ? PRICELESS
Just so you know. I am using a Computer power supply and the servo is steady as a rock and moves smoothly. But the 7805 VR is getting smoking hot fast cant leave on more than 30 seconds. HEAT SINK?
Then I hooked up a older heathkit 0-15 volt supply and it began to have a very short jerky action continuously, it does respond to pulse change but shaky while doing it.The reason I mention this is how filtered is a B+ supply from a car battery
Just so you know, I am 51y/o and I must say I felt like a little kid at Christmas when that Servo Started to respond.
R1 that you changed to 1k5, you really should replace with the stated value (1k2), as this is calculated for minimum temperature drift.
Don't forget that we still have to get the timing values tuned correctly (not a big deal, but it has to be done).
I don't happen to have a 1.2k resistor, local or from my parts store as a tried to get them. If I add a 1k+220ohm in series will that be close enough to hold the temp drift?
in the video you see the Proto board. All 3 circuits are there, Signal Gen, Freq to voltage circuit and final Servo control section.And I did try tying it all together and it did work as I increased and decreased frequency the Servo responded ~pretty much as it should. There was a couple issues but like you said there are other things to be finished. Before we discuss this stuff.
Well I am off to shopping also, my G/F is taking me to a tool store for me to pick my goodies I like it that way I get just what I want from Santa
Then off to her house and I will be kept captive for the evening.
That depends on what these issues are, so please do tell.
Another possibility is that there is a slight jitter in the signal (but again, this is most likely from the servo taking power thereby lowering the supply slightly, which then makes it a command to go the other way, back and forth).
I measured two 3003's (used) with virtually identicle results.Idle current = 26maUnloaded transit current = 105maStall current = 430maat 5.1 volts. I have no 6.0 volt packswith which to test.
This is the case I believe as you stated. If I restrict the servo slightly with my finger and the torque increases the small signal time also increases as it is unable to switch the motor direction as easy. And the taking of power is extended before switching the servo to the other direction
I was searching for some info on the 3003 servo and came across a few people that were test current draw for this motor. here are there results,Re: Futaba S3003 servo current draw? QuoteI measured two 3003's (used) with virtually identicle results.Idle current = 26maUnloaded transit current = 105maStall current = 430maat 5.1 volts. I have no 6.0 volt packswith which to test.I added up to 44uf in parallel with the supply right at the plug going to the Servo. But no luck on dampening it. I am going to buy a couple larger Caps to day up around 100uf or a little bigger as I believe this is where the problem is . AS you have said.
You know when you said it had been over 3 months of work on this I thought I would fall over It is really a wonderful thing that 2 people half way around the world never speaking a spoken word can do this.When I was 10y/o if you had told me that some day I would be building a electronic circuit with another man thousands of miles away on a key board typing. I would have just had a good laugh
Hope your holiday is going well? I have not replied in a while as you were needing R&R and I was not wanting to interrupt for a while.
I see you have stop by the forum a couple times now, so I guess I wont be rude by dragging you back to this circuit
Today I will be making the the changes on the direct wire setup from the PSU to the Voltage supply to the 7805 and applying the caps as suggested. Then I will update you. how that goes.