PDA

View Full Version : Are caps still necessary with 2.4 GHz Cars?


Traveler
2012.02.10, 08:37 PM
Rebuilding some older mod motors and wondering if I can remove the caps. All my cars are 2.4 MR-03s. Thanks

EMU
2012.02.10, 09:09 PM
I dont think they are necessary for 2.4ghz.

NoBrainer
2012.02.11, 05:44 AM
I think you are right EMU, but caps are there to reduce noice from the motor to other electronics.
So I would keep them. Nothings more irritating than interferance that you just can't understand why.
Just my point of view.

nicov
2012.02.11, 08:13 AM
If you talk about the caps on the motor connection, they are also here to reduce the sparkles on the collector, avoiding to burn the collector.

Bodom
2012.02.11, 04:44 PM
EMU is not right here :) Caps are needed.

Traveler
2012.02.14, 08:46 AM
Thanks for the input guys! I was hoping for a unanimous position, but guess I'll have to resolve for myself by trying with and without. If I learn anything fascinating, I'll post it here :)

color01
2012.02.14, 08:52 AM
EMU is not right here :) Caps are needed.
Curious why you say this. I've been running all sorts of motors in my Mod 03 with and without caps and haven't ever noticed a difference. PN motors don't even come with caps anymore AFAIK, so if they are necessary then we would have to rush out and buy caps overnight. :eek:

Rune
2012.02.14, 09:14 AM
On ASF boards we have been running without caps for the last two years.
Never experienced any problems.

EMU
2012.02.14, 12:31 PM
The caps on the motors reduce noise for the 27mhz AM band. On 2.4ghz, I have not seen any difference with or without them. On AM, if a cap was loose, you would feel it in glitches.

oXYnary
2012.02.14, 05:10 PM
The caps on the motors reduce noise for the 27mhz AM band. On 2.4ghz, I have not seen any difference with or without them. On AM, if a cap was loose, you would feel it in glitches.

More than just AM. We used them for decades with FM as well. Nicov has the best answer. They also reduce the spikes in the motor use to reduce motor wear on the commutator.

You may not be noticing any difference because the ASF hides most of it. BUT. It still exists. The 2.4 band is still a form of EM, while the motor without caps puts out EM energy. As well as your electronics.

Really? Is it that hard to put on the caps? If nothing else you get longer brush/commutator life.

Traveler
2012.02.14, 07:43 PM
Really? Is it that hard to put on the caps? If nothing else you get longer brush/commutator life.

Actually, I've found it quite difficult to solder the cap to a new can (which I will have to do with a few motors). I've roughed up the can with a file, used flux and still had difficulty making a nice joint. Plus, with the 94-98mm mounts, where you solder to the can and how much solder you get on that joint can interfere with the diff shaft, so no, I don't think its easy. But now we are getting off topic, so lets get back to the subject.

color01
2012.02.14, 08:10 PM
More than just AM. We used them for decades with FM as well. Nicov has the best answer. They also reduce the spikes in the motor use to reduce motor wear on the commutator.

You may not be noticing any difference because the ASF hides most of it. BUT. It still exists. The 2.4 band is still a form of EM, while the motor without caps puts out EM energy. As well as your electronics.

Really? Is it that hard to put on the caps? If nothing else you get longer brush/commutator life.

One part you're neglecting I think is the fact that the newer ASF boards have several capacitors inside the board itself that serve the same function as the caps on the motor. On the MR03 at the very least we know there's a cap right between the motor terminals. If you care enough about this, we can take a look at that cap's value and you'll most likely see that it filters out noise in the 2.4GHz band, just as the add-on caps used to do for our AM 27MHz.

In my experience the caps' effect on brush/comm life is nearly negligible compared to the starting quality of the brushes and comms themselves. PN and Kyosho comms last eons compared to Tamiya Mini-4WD comms, and the brushes... well, every batch I've bought lasted a very different amount of time thanks to different driving conditions. It would be nice to have a scientific test for brush life with and without motor caps, but I replace brushes less than once a year so I'll admit I don't really care. :o

NoBrainer
2012.02.15, 02:16 AM
On the MR03 at the very least we know there's a cap right between the motor terminals. If you care enough about this, we can take a look at that cap's value and you'll most likely see that it filters out noise in the 2.4GHz band, just as the add-on caps used to do for our AM 27MHz.

Does this apply to the MR-02? with 2.4GHz that is.

pomme de terre
2012.02.15, 08:28 AM
Does this apply to the MR-02? with 2.4GHz that is.

Yes. It's just oriented laterally between the motor terminals rather than longitudinally like the MR03 board.

Bodom
2012.02.15, 08:29 AM
Curious why you say this. I've been running all sorts of motors in my Mod 03 with and without caps and haven't ever noticed a difference. PN motors don't even come with caps anymore AFAIK, so if they are necessary then we would have to rush out and buy caps overnight. :eek:

I say this because of this (http://mini-zracer.com/forums/showthread.php?t=37440) thread, which proves me that a motor CAN cause glitching on 2.4 board.
As you already said the board itself has a capacitor between the motor terminals.
I am curious - have you tried KT-18 + car without motor caps?

color01
2012.02.15, 04:09 PM
Ah, I see what you mean. I'm inclined to say that a bad motor is a bad motor, though -- mugler had an F1 car with a serious steering glitch even though there were caps properly soldered onto the motor. I swapped out that faulty 70t with a new 80t (no caps) and the glitching instantly went away. I imagine this could be a current drain issue so we're going to try a 50t (no caps) next outing and see if the glitching comes back. If it doesn't, then we have one control data point indicating that a crappy motor is going to cause glitching whether you put caps on it or not. And that just makes this question more difficult to answer, lol...

oXYnary
2012.02.15, 04:33 PM
Ah, I see what you mean. I'm inclined to say that a bad motor is a bad motor, though -- mugler had an F1 car with a serious steering glitch even though there were caps properly soldered onto the motor. I swapped out that faulty 70t with a new 80t (no caps) and the glitching instantly went away. I imagine this could be a current drain issue so we're going to try a 50t (no caps) next outing and see if the glitching comes back. If it doesn't, then we have one control data point indicating that a crappy motor is going to cause glitching whether you put caps on it or not. And that just makes this question more difficult to answer, lol...

Unless the caps on that motor were faulty...

Try without any caps on that glitching motor. Then try with a new set of caps for a better theory.

LuckyDuc
2015.03.03, 06:55 PM
Just wondering if any conclusions have been made in regards to NOT needing to solder caps on the motors for 2.4ghz cars.

I have a Mini Z optima and purchased a PNWC 70 Turn Stock Motor to use with it, and noticed that there were no caps included.

I do not want to order caps separately and solder them on if they are not necessary with the ASF cars.

cowboysir
2015.03.03, 07:33 PM
Ive found no need for caps. All my ASF cars run the same whether thay have a motor with caps or without.;)

Pierro
2015.03.04, 03:12 PM
Hi!

I used to personnaly think the caps weren't useful anymore since the age of 2.4Ghz but two years ago I had to change my mind.

We were running kyosho stock motors in the stock category and i had a really annoying glitch problem on my chassis. The car was running perfectly fine but sometimes, all of a sudden, I had a big glitch that sent my steering all way left. Making the car pretty unpredictable to drive. I tried many things, re solder other etc until someone told me to resolder the caps on the motor. Once done, I never had the problem again.

So for me, YES, the caps are still necessary on a motor despite 2.4Ghz.

DMALMAD
2015.03.04, 03:29 PM
It really depends on the motor and the situation. For me personally I have never used capacitors.

379
2015.03.12, 10:42 PM
I would vote no. I am using two pn racing 70t motors in a 1/35th rc KV-2 tank with no caps and no interference issues. I am using spektrum radio gear, not the perfex stuff in a mini-z, but on the other hand one of the two antennas on my ar6110e is less than an inch from the brushes of one of those motors. Both motots are right next to each other, too, pretty cramped vehicle.

I would wholeheartedly say that, barring unusual circumstances or part failure, 2.4ghz radios just dont care about the interference produced by a brushed motor. If they, as a rule, did, my tank would have problems with it.

byebye
2015.03.13, 05:24 AM
Without schematics I cant say positively that caps are built into the board but from the looks there is more small stuff added than what you see on the AM stuff.

The 2.4 boards are just not as susceptible as the older AM boards.

Jshwaa
2015.03.13, 07:46 AM
Without schematics I cant say positively that caps are built into the board but from the looks there is more small stuff added than what you see on the AM stuff.

The 2.4 boards are just not as susceptible as the older AM boards.

The caps on the motor have nothing to do with the frequency of the radio. They are there to absorb some of the inductive spike that occurs when your motor switches poles on the commutator. One thing you should notice with the addition of the caps is that the blue plasma arc between the brushes and the commutator should not be as intense. The stock motor on my MR-03S went one step further and put a MOV (metal oxide varactor) between the elecs and the motor. This is to absorb even more of that energy, so that the motor is harmless to the FET's.

The hotter the motor you run, and the higher current it draws, the more dramatic the arcing is and it becomes more possible for your FET's to take damage. Especially when doing a quick forward to reverse, or vice versa. That creates the biggest arcs possible.

As far as caps on the 'board', yes there are several of them. The most obvious are the big yellow/orange ones on the top side of the board.

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/DSCN2508.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/DSCN2508.jpg.html)

Those are there to help stabilize voltage on the board, so that the digital components aren't affected by noise.

There's also caps clustered around the square shaped receiver IC, for filtering the radio transmission. All three of those parts on the bottom left of the board are capacitors. All the little 'brownish' and 'greyish' looking parts are capacitors. The little black ones(two legged, not 3 legged) are resistors. There's a couple inductors in there too, which you couldn't tell they were without using a meter. Inductors are shorts to DC current. Caps will give you a varied resistance reading as they charge or discharge when you measure them, and resistors should give you a static resistance reading when you measure them.

Jshwaa
2015.03.13, 09:08 AM
http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/Cs%20and%20Rs.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/Cs%20and%20Rs.jpg.html)

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/Cs%20and%20Rs%202.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/Cs%20and%20Rs%202.jpg.html)

The black three-legged parts are transistors (NPN bipolar junction transistors to be specific)

The large round part, semi-covered in white goo, is a relatively large inductor for stabilizing the current output of the board's power conditioning stage. Your battery voltage varies quite a bit during run-time, and this little power station assures that the voltages seen by the digital components is the same all the way up until your cells start to die out, so that your elecs stay responsive throughout all voltage variations.

The little silver cylindrical part is a crystal oscillator for the receiver IC's clock and radio receiver demodulation.

So, to answer the question as to whether or not the motor capacitors are necessary with the 2.4GHz cars...

The answer does not involve a relationship between the radio frequency and the motor capacitors. If you guys notice any differences in how robust the 'newer' elecs are compared to older models, then this difference is more than likely embedded in the FET's used, which house a protective diode in them for protecting the FET from the previously mentioned inductive voltage spikes produced by the motor.

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/NchanPchan.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/NchanPchan.jpg.html)

Are the caps necessary? In my experience, so far, no... I've ran a 32T with a 14T pinion and Li-Fe's, and although the arcing is substantial, my FET's are still running like a champ. I can't speak for the long run though, however I can't think of a more harsh set-up from my FET's perspective. Of course I could simply 'stall' the motor, but this does not produce arcing(peak voltage condition), it produces a peak current condition.

Jshwaa
2015.03.13, 10:38 AM
If we look across the motor connections with a scope as we throttle from reverse to forward quickly, we can capture the phenomenon that can be a FET killer...

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/DSCN2570.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/DSCN2570.jpg.html)

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/motor%20spikes.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/motor%20spikes.jpg.html)

This was done with 4-cell eneloop pros and a 32T motor with no caps.

I set the trigger so that it would catch the exact moment that I broke a voltage threshold. I switched from reverse to forward very quickly, and you can see the change in the voltage pattern as I did. If you take into account the negative swing with respect to the abrupt positive swing, you can see that there is a 15.4V peak to peak voltage spike.

Referring to the Si4562DY data sheet...

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/4562_stats.jpeg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/4562_stats.jpeg.html)

As an absolute maximum, the FET can only handle a 20V potential between its drain and source pins, which is what your motor is across during run-time. If, in the event that these spike magnitudes exceed this maximum, the FET degrades. This does not necessarily happen immediately, but can happen over time, and then the FET fails. And keep in mind that the above analysis was done while the wheels were free spinning. Your motor experiences more load and the spikes can be even bigger when running on the ground. And as far as the motor caps are concerned, these voltage spike magnitudes are reduced because the energy is being absorbed by the cap instead of being able to peak as shown in the pic.

TheSteve
2015.03.13, 03:21 PM
Are you able to perform the scope measurements with and without capacitors across the motor and see a difference?

379
2015.03.13, 04:55 PM
Your motor experiences more load and the spikes can be even bigger when running on the ground.

Almost makes me wish I could somehow put a scope across the terminals of both motors in my tank, then thrash the living hell out of it. Abrupt turns, abrupt stops, steep climbs, soft surfaces, the works. It seems logical that, if anything on this scale is gonna produce the biggest spikes, it'd be something heavy and hard to maneuver.

byebye
2015.03.13, 06:12 PM
The caps reduce noise traveling up and off the motor wires. This causes interference. I don't believe the 2.4 ghz boards are affected by this because of the caps in between the positive and negative contacts on the board. . I can only speculate that PN doesn't include them on their motors because they know this already seeing as they've made they're own 2.4 board...

Jshwaa
2015.03.13, 10:56 PM
Are you able to perform the scope measurements with and without capacitors across the motor and see a difference?

Will do that when time allows. I didn't want to mess around with soldering caps back on my motor when I may need to get back into it. When time allows, I will do up the same analysis with a motor that has the caps on it, and then take them off and do it again.

Jshwaa
2015.03.18, 08:14 AM
The caps reduce noise traveling up and off the motor wires. This causes interference. I don't believe the 2.4 ghz boards are affected by this because of the caps in between the positive and negative contacts on the board. . I can only speculate that PN doesn't include them on their motors because they know this already seeing as they've made they're own 2.4 board...

This is true too. If you are next to sensitive equipment (AM radio), you may hear a click in the audio if your motor is close enough to the antenna. May even hear a high-pitch whine kind of like a poorly installed car stereo where you can hear the alternator through the audio.

As a matter of fact, this 'back EMF' produced by the motor is causing problems with my dynamometer project. I am experiencing the main CPU reset itself in the even that I coil the motor wiring and place that coil close to the wiring to the tachometer input. The tachometer wiring is coupling in the noise and delivering it right to an input on the CPU board. The spike interferes with VCC of the CPU and actually disrupts the supply, and induces a power cycle effect like turning the power switch off then on really fast.

I will need to be careful how I route the power cabling with respect to the tachometer cabling to prevent this. It's amazing how much noise motors can produce.

The motor caps 'could possibly' be just a hoop that Kyosho had to jump through to satisfy the FCC too, because any electronic device has to conform to rules to ensure that it only can produce a certain level of interference to other electronic devices. Without the caps, the mini-z may float into a category of interference that would make it illegal to mass produce.

Just a couple other ideas about the motor caps...

LED
2015.03.18, 11:25 AM
Question, why are the caps on the motor and not on the board? Do they need to be a close as possible to the source of the noise?

byebye
2015.03.18, 03:09 PM
Question, why are the caps on the motor and not on the board? Do they need to be a close as possible to the source of the noise?

Yes to the second question.

379
2015.03.18, 04:20 PM
Yes to the second question.

Wouldn't they also need to vary their capacitance to account for minor differences in the motors that change the noise put out by said motor? I can't imagine the PN 70ts I'm using in my tank put out the same level or type of RFI that the stock Kyosho motor does, that a bog-standard Maibuchi 130 from the 50 cent bin does, that a 20t bonkers bonneville special motor would.

Jshwaa
2015.03.18, 06:45 PM
Wouldn't they also need to vary their capacitance to account for minor differences in the motors that change the noise put out by said motor? I can't imagine the PN 70ts I'm using in my tank put out the same level or type of RFI that the stock Kyosho motor does, that a bog-standard Maibuchi 130 from the 50 cent bin does, that a 20t bonkers bonneville special motor would.

The EMF is at the frequency of the motor's rotation, so you should not see a difference in the 'frequency' of the noise if any two motors were running at the same speed, no matter what the differences in the motor's composition may be. However, I did notice a ringing effect with the motor without caps that did not seem to exist with a capped motor. These harmonics(like octaves on a piano) occur at multiples of the main fundamental frequency, and could reach frequencies and amplitudes that could disrupt nearby electronic devices.

I'm starting to lean on this as being the main reason for the caps in the first place. It is easy for all of us to assume that it is to protect the mini-z, when it could in fact be to protect everything else 'from' the mini-z. Anything that relies on a consistent clock cycle that is within the same frequency as one of the EMF spikes could get jammed and cause a failed transmission or an audible click, or in some cases a resetting of a microcontroller.

At any rate, as long as you have a cap value that produces the filtration needed for all frequencies that correspond to an entire motor's range of rotational velocity, that cap value should be good for any other motor that operates within that same band of velocities, as all of the fundamental frequencies produced by the motor's should be within the same range.

It would take some pretty extensive theory testing to nail down the exact values that would optimize the filtration of each and every singular motor, which isn't worth it in my opinion. I usually wait until noise is a problem, and try to filter until it isn't. The motor spikes have not caused any issue with the operation of my mini-z, but they are causing issues with some of my other devices....

TheSteve
2015.03.18, 07:55 PM
I think the simple answer is that they are not strictly required with a 2.4 GHz car but you're still better off with them.

Jshwaa
2015.03.19, 08:12 PM
So here's a little experiment I did with my scope and a motor with caps and motor without. Yea, I know it's not apples to apples if it's not the same motor, but bear with me... the cap effect is still obvious...

If I grab a wire with my scope probe and hold it just above the motor, I can get a view of the electric field produced by the motor.

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/DSCN2616.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/DSCN2616.jpg.html)

Here's the same motor, and a view of the amplitude of the electric field vs. time at the wire above that motor.

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/DSCN2617.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/DSCN2617.jpg.html)

Here's a 'different' motor, which does 'not' have caps...

http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/DSCN2618.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/DSCN2618.jpg.html)

And then here's a snapshot of the scope screens of each motor, with the amplitude jacked up a little bit on each so the harmonic spikes are a little more clear...

With caps...
http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/with%20caps.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/with%20caps.jpg.html)

Without caps...
http://i83.photobucket.com/albums/j314/Jshwaa/Mini-Z/without%20caps.jpg (http://s83.photobucket.com/user/Jshwaa/media/Mini-Z/without%20caps.jpg.html)

If the caps would allow for easy access to the armature, I wouldn't have a problem with having them for cleaning out that noise, but as long as that noise is not causing my mini-z any harm, and I want to work on my motor, the caps are going to have to go...

cowboysir
2015.03.19, 09:11 PM
If the caps would allow for easy access to the armature, I wouldn't have a problem with having them for cleaning out that noise, but as long as that noise is not causing my mini-z any harm, and I want to work on my motor, the caps are going to have to go...

I really don't understand this statement (that you've made a couple times)...you have all this techy motor BS and take the time to show us different "noise" graphs but you find that caps are impeding you working on your motor? Is de-soldering one connection point on each side that difficult or time consuming?:D

very cool info....totally beyond what's needed to discuss the thread but gotta love them props.:D

Jshwaa
2015.03.20, 12:17 AM
I really don't understand this statement (that you've made a couple times)...you have all this techy motor BS and take the time to show us different "noise" graphs but you find that caps are impeding you working on your motor? Is de-soldering one connection point on each side that difficult or time consuming?:D

very cool info....totally beyond what's needed to discuss the thread but gotta love them props.:D

Yea, well, whatever... Thanks, I guess. Now to get this scope, 'er meter, 'er power supply to desolder caps for me... pfff...

arch2b
2015.03.20, 03:29 PM
i for one love seeing the science behind the technology :D it's over my head but love pouring over all the tech talk, pictures, diagrams, etc.

TheSteve
2015.03.20, 04:20 PM
I appreciate your time to connect up the scope and attempt to see what is going on but I am not sure how valid it is. A floating scope probe rarely gives any kind of result you can trust. I think a much better test would be to connect the scope probes properly to the motor terminals and then look at the AC signals that are being generated. If you want to look at the true spectral(RF) noise that is being generated then you need to use a proper tool for that - a spectrum analyzer.

Jshwaa
2015.03.20, 08:27 PM
TheSteve, I understand your thought process with that...'no circuit without the ground connection', right? Well that is how electro-magnetic fields work. The magnetic field produces an electric field, where the potential is still there because it is disrupting the normal state around it. It can exist because it is periodic, with periods that are very small, but can have magnitudes that can be relatively high.

As far as the validity of the test, well that would be more apparent with a video, as you can see the amplitude of the periodic signal go up and down in proportion to the distance the wire was from the motor. The wire is acting like an antenna, picking up the electric field from the motor, just as a radio would pick up the signal from a radio station. Of course as you get closer to the radio station, your reception improves, just as the wire does in picking up noise by being closer to the motor.

And by the way...Thanks to all of you that can read one of my posts and either take it or leave it. I like the opportunity to use the public domain to not only share what I've learned over the years, but to reaffirm it for myself. Integrating something you've learned is important, otherwise the knowledge is useless. I'll try not to fill up the internet in the process, and hopefully I can get by some of the funny particulars of the natives in the process...

TheSteve
2015.03.20, 09:59 PM
TheSteve, I understand your thought process with that...'no circuit without the ground connection', right? Well that is how electro-magnetic fields work. The magnetic field produces an electric field, where the potential is still there because it is disrupting the normal state around it. It can exist because it is periodic, with periods that are very small, but can have magnitudes that can be relatively high.

As far as the validity of the test, well that would be more apparent with a video, as you can see the amplitude of the periodic signal go up and down in proportion to the distance the wire was from the motor. The wire is acting like an antenna, picking up the electric field from the motor, just as a radio would pick up the signal from a radio station. Of course as you get closer to the radio station, your reception improves, just as the wire does in picking up noise by being closer to the motor.

And by the way...Thanks to all of you that can read one of my posts and either take it or leave it. I like the opportunity to use the public domain to not only share what I've learned over the years, but to reaffirm it for myself. Integrating something you've learned is important, otherwise the knowledge is useless. I'll try not to fill up the internet in the process, and hopefully I can get by some of the funny particulars of the natives in the process...

Yes, I know exactly how electromagnetic fields work. Believe it or not you're not the only one here that might be educated.
Anyway, you clearly have no interest in learning from others, only saying what you think you already know.
There are lots of people here that do appreciate you sharing your knowledge but you may also want to realize you might also be able to learn something.

KWT
2015.03.20, 10:14 PM
yes, i know exactly how electromagnetic fields work. Believe it or not you're not the only one here that might be educated.
Anyway, you clearly have no interest in learning from others, only saying what you think you already know.
There are lots of people here that do appreciate you sharing your knowledge but you may also want to realize you might also be able to learn something.

+1 :) :) :)

Jshwaa
2015.03.20, 11:40 PM
Yes, I know exactly how electromagnetic fields work. Believe it or not you're not the only one here that might be educated.
Anyway, you clearly have no interest in learning from others, only saying what you think you already know.
There are lots of people here that do appreciate you sharing your knowledge but you may also want to realize you might also be able to learn something.

Well, my apologies. I was trying to have a discussion with 'you' and address something 'else' at the same time and it came out bad. However, in your effort to challenge the validity of an experiment I would have thought you might want to back up your stance on that. Regardless of our educations, if the pictures aren't proof enough of what I'm saying is true, do you expect me to concede to a couple of your sentences of mere nay-say? By all means Steve, suggest something to me that could further bring us closer to an understanding. I love learning. However if all you got is your thumbing of your nose at ideas, I don't know what else you want from me.