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Discussion Starter · #1 ·
Hi all,

I have a basic understanding of manual transmission and can drive fine most of the time without stalling, generally smoothly.

however, I have never really been taught how to drive in a sporting fashion, or how to match revs, or how to downshift other than just move from a higher gear to a lower gear.

so, a few questions if I may to the more knowledgeable here…

1) when shifting into first there is a balance between gas an letting go of the clutch. I usually do this pretty slowly and the slower I let out the clutch, the better it seems to be. Should I practice letting out the clutch quickly once I find the bite point?

1a) am I supposed to increase throttle as I release clutch from bite point, or hold throttle steady?

1b) if I get on the throttle a bit when I hit the bite point coming into first from a stop, can I release the clutch quickly as I increase the throttle relatively quickly… or is this called dumping the clutch, is this bad?

2) when shifting gears up if I am above say… 3k rpm, am I supposed to wait until I am fully clear of the clutch before I get back on the throttle or am I supposed to initiate throttle before fully letting go of the clutch as you do in 1st?
(I usually start to accelerate just before I’m fully clear of the clutch.)

3) occasionally I have perfectly smooth shifts that are done as if it was an automatic transmission, they are perfect. I don’t know why this happens and I’d like to have those every time. Can anyone tell me why some shifts (up shifts in particular) are perfect and how to achieve those

4) when downshifting I do not use any throttle and I let the clutch out slowly from the bite point to avoid bucking… am I doing this right?

5) what does it mean to “heel to toe”?
I have read a lot and heard a lot about rev matching and heel to toe, but I don’t actually know what it is.

thank you so much to anyone who can answer these basic manual questions, I can drive a manual OK and I don’t think that anyone except very good drivers would notice my shortcomings, but I want to learn to drive the correct way and I’d love to be able to perfectly upshift and downshift so that there is no bucking at all.

there are a few threads here on manual trans, but nothing that exactly answers these questions. Please feel free to be as technical as you like as I’m interested in not just the practical aspects but also what the engine/transmission are doing.

alternatively if there is a good book or video then feel free to link!

I did watch the smoking tire video and it was helpful, but didn’t cover everything.
 

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Sorry but you almost need someone riding next to you in the car to help with all this. Many of the answers to your questions I find hard to put into words in this forum.
I agree. Spend a couple of hours with a good instructor.
Regarding "heel and toe", it's actually a misnomer. The technique is to brake with the left side of the foot while depressing the throttle pedal with the right side of the foot, during downshifts. This enables a smooth downshift while braking for a bend.
 

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It's sometimes very useful to throttle and brake at the same time. If you're braking into a corner near the limits of grip and need to downshift, it's best to put a little throttle on to avoid engine braking when the clutch is released, otherwise the car will end up doing a handbrake turn (effectively). As Viv says, I'd personally do this with my pinky toe by twisting my foot. Not necessary most of the time, but if you're at 9/10ths it's advised.

 

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👍🏻

I’ll look for an instructor.
I never got more than a very basic manual trans introduction from an uncle who is no longer with us.

brake and throttle at the same time?
I never knew that was ok to do!

thanks for the vid, let me watch that…
The object of "heel toe" is during the downshift, you want to get the revs up to what they will be when the lower gear begins engaging. So, simply speaking, you clutch, downshift, pop the revs to the approximate higher revs, while smoothly releasing the clutch. No brake needed in this scenario. However, sometimes you will need to do this going into a corner. You will find in your Porsche, that with your brake on, the gas pedal is pretty darn close to the same height as your depressed brake pedal. So, going into the corner at speed, you brake with the ball of your right foot, clutch with your left foot, down shift the shifter and roll your right foot onto the gas pedal increasing the revs while releasing the clutch. The coordination takes practice. Actually, in Sport or Sport+, it should do the rev matching for you.
 
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Well, @DM5PAV, if you aren't trolling :) we can try to answer your questions. Much of what you ask is learned by doing and being sensitive to how the car behaves. A basic knowledge of how a gearbox works will help.

The ratio of engine speed to car speed is determined by the gear selection. The output shaft of the gearbox. manual or auto, is directly connected to the car. The input shaft is connected to the engine via the clutch. Between them is a secondary shaft which carries pairs of gear with different ratios between input and output. Only one of those pairs can be engaged at a time. Actually they are all meshed but only one can be active. A gear pair is made active by a set of special teeth, sometimes called dogs, which lock one and only one pair to the secondary shaft. The other pairs are free to spin on the shaft. To select a gear with a different output/input ratio from what the car and engine are doing at that time, two things have to happen.

First (and this is a simplistic explanation with a few details technically incorrect), the input shaft and all the gear pairs must be made to spin at a new rate to match the new gear choice. This is so that the drive dogs which engage the new gear don't grind when trying to mesh. All modern gearboxes have a lockout mechanism called a synchronizer or synchro (invented by Porsche, BTW) which prevents the dogs from meshing until they are spinning at the same speed. That synchro also provides friction between the input and output dogs to force them to the same speed until their speeds match. Manual "double clutching" (not to be confused with "double-clutch" as a gearbox type such as the PDK) is a way to "help" the synchro. Instead of de-clutching then pushing on the shift knob until it slips into gear, you de-clutch, shift into neutral, engage the clutch, rev the engine until it is right for the car's speed with the desired new gear, de-clutch, push the shift knob, then engage the clutch. You rarely need to double-clutch when upshifting because friction and oil viscosity in the gearbox make the input shaft slow down on its own, which is what the synchro would be doing. Downshifting however means the input shaft has to spin faster, so if you help it out you may be able to shift quicker. (Double-clutch gearboxes like the PDK actually have two secondary shafts, one with the odd numbered gears, one with the even numbered gears. Each has its own clutch but only one is engaged at a time. A computer pre-selects the gear on the disengaged shaft based on how you are driving, then it executes a shift simply by releasing one clutch and engaging the other. It's fast, smooth, and expensive.)

Second, even with effective synchros to make the gearbox internals work smoothly, the engine must be made to spin at the correct speed for the new selection or else when the clutch engages the car will lurch forward or backward and some amount of clutch slip will occur. That is what rev-matching does. And if you double-clutch as described above, you end up with the engine at the correct engine speed so rev-matching is implicit. The engine doesn't have to be spinning at exactly the correct speed for the car, and when starting from a stop a perfect match between car and engine speeds is impossible of course. But less clutch slip means it will last longer, and smooth shifting is always good for car stability (and for passenger state of mind). As with helping the synchro, rev-matching is more important for downshifting because you are usually braking as well as needing the engine to spin faster. When you are upshifting you simply lift off the gas pedal and the engine slows on its own.

Heel/toeing is a way to operate both brake and gas pedals simultaneously with the same foot. It lets you brake while rev'ing the engine for either rev-matching or the complete double-clutch operation. When I first learned it, I put my toe on the brake pedal because it fit the car's pedal layout and I could modulate the brake with ankle movement. Magazine articles described is as heel on the brake, which meant modulating the brake with knee flex, not a good idea IMHO at the time. As @Viv said, it is often done with toe and the side of the foot. Whatever. With modern gearboxes, especially with automatic rev-matching, it is unnecessary.

After all that, it should be obvious how to shift. You want to release the clutch with as little slip and with as little lurching as possible. The slower you release the clutch, the more time it spends slipping but the more gently the engine and car come to terms. So release the clutch quickly with the engine already as close to the correct speed for the new gear as you can get it. Clutch slip is unavoidable when starting out from a stop. Otherwise you try to make the engine spin at the right speed for any new gear, and then release the clutch as quickly as is compatible with smoothness. You learn by feel what works. The goal is to be smooth but also quick.
 

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Please don't take this the wrong way.

It is expected that people on here are offering advice from a performance perspective - sharing videos of pedal boxes with people on tracks etc. This is a Porsche forum.

But if you are struggling to set off smoothly and just get regular changes good regularly, those sort of instructions are not going to be helpful.

Jim's post on how the car is working is useful, if you use that to translate to what you are doing.

But overall, at this stage, put performance out of your mind. Just get in tune with how your actions relate to the mechanics of the car. Once you can trundle around normally, smoothly and without too much active thought, that is when you can look to advanced techniques.

Driving a manual OK isn't hard, don't make it hard to start with. Don't build it up as a big thing. There is a lot of scope to bring advanced techniques into it later. But your first few thousand miles is not it.

This is a much more useful level for the questions you're asking:
 

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1) when shifting into first there is a balance between gas an letting go of the clutch. I usually do this pretty slowly and the slower I let out the clutch, the better it seems to be. Should I practice letting out the clutch quickly once I find the bite point?

I used to let the clutch out relatively quickly. This resulted in never having to replace a clutch but did not at all result in Dynaflow smoothness. My GF likes smooth shifts so now I let the clutch out a little slower with a little more control however I recognize the clutch may not now last beyond when I trade for a new car.

1a) am I supposed to increase throttle as I release clutch from bite point, or hold throttle steady?

Usually one is accelerating to one degree or another once the clutch is engaged so, yes, give it the amount of throttle appropriate for the acceleration you want.

1b) if I get on the throttle a bit when I hit the bite point coming into first from a stop, can I release the clutch quickly as I increase the throttle relatively quickly… or is this called dumping the clutch, is this bad?

Actually, I am stoping trying to respond to the questions now as I don't know of any Betty Crocker answers to your questions. You just have to drive a manual shift car and get the feel for it. There is no right and no wrong, you just have to do what feels right for you. I suggest you learn and get experience with a car easy to shift and, IMO, that is not a Boxster. Back when I learned it was a VW Beetle and I dont have a clue if anything else is available now. Manual transmissions are almost impossible to find now. So just takle your Boxster out on a quiet Sunday morning and just practice stopping, going, up shifting, and down shifting and practice more.
...

5) what does it mean to “heel to toe”?
I have read a lot and heard a lot about rev matching and heel to toe, but I don’t actually know what it is.


Don't even think of this now. No need to. Also, my Boxster matches downshift RPMs in Sport mode automatically and that really makes me look like I know what I am doing.
 

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So I'm getting a PDK but used to drive a manual for the first 10-15 years of driving as I couldn't afford an automatic (+$1-$2K) when starting out in the job market. These videos made it clearer than any written description, so thank you. I performed those functions all the time, yet never knew that's what heel and toe really was. Foot wear affects performance a lot especially boots or old school sneakers.
 

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Discussion Starter · #13 ·
1) when shifting into first there is a balance between gas an letting go of the clutch. I usually do this pretty slowly and the slower I let out the clutch, the better it seems to be. Should I practice letting out the clutch quickly once I find the bite point?

I used to let the clutch out relatively quickly. This resulted in never having to replace a clutch but did not at all result in Dynaflow smoothness. My GF likes smooth shifts so now I let the clutch out a little slower with a little more control however I recognize the clutch may not now last beyond when I trade for a new car.

1a) am I supposed to increase throttle as I release clutch from bite point, or hold throttle steady?

Usually one is accelerating to one degree or another once the clutch is engaged so, yes, give it the amount of throttle appropriate for the acceleration you want.

1b) if I get on the throttle a bit when I hit the bite point coming into first from a stop, can I release the clutch quickly as I increase the throttle relatively quickly… or is this called dumping the clutch, is this bad?

Actually, I am stoping trying to respond to the questions now as I don't know of any Betty Crocker answers to your questions. You just have to drive a manual shift car and get the feel for it. There is no right and no wrong, you just have to do what feels right for you. I suggest you learn and get experience with a car easy to shift and, IMO, that is not a Boxster. Back when I learned it was a VW Beetle and I dont have a clue if anything else is available now. Manual transmissions are almost impossible to find now. So just takle your Boxster out on a quiet Sunday morning and just practice stopping, going, up shifting, and down shifting and practice more.
...

5) what does it mean to “heel to toe”?
I have read a lot and heard a lot about rev matching and heel to toe, but I don’t actually know what it is.


Don't even think of this now. No need to. Also, my Boxster matches downshift RPMs in Sport mode automatically and that really makes me look like I know what I am doing.
hey, I appreciate the responses. It’s not information that I was ever really given and again on a day to day drive… no one has ever complained about my driving. I got about a 25min introduction to manual cars and that was it. I drive for quite a few years but after coming back to manuals for the fun of it with this car, I realized… I have no real knowledge of anything to do with driving an manual transmission. It’s all just muscle memory, and I’d like to actually understand the workings of the car and be able to get those perfectly smooth shifts every time by knowing the what and why. Please forgive me if that sounds too academic, or formulaic, which is what I think you meant by Betty Crocker.

heel to toe is just a phrase I’ve heard and again realized I don’t even know really what that means. But it looks like there is a nice video there which I will shortly watch when I have the time.

thanks much!
Happy driving!
 

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Discussion Starter · #14 ·
Please don't take this the wrong way.

It is expected that people on here are offering advice from a performance perspective - sharing videos of pedal boxes with people on tracks etc. This is a Porsche forum.

But if you are struggling to set off smoothly and just get regular changes good regularly, those sort of instructions are not going to be helpful.

Jim's post on how the car is working is useful, if you use that to translate to what you are doing.

But overall, at this stage, put performance out of your mind. Just get in tune with how your actions relate to the mechanics of the car. Once you can trundle around normally, smoothly and without too much active thought, that is when you can look to advanced techniques.

Driving a manual OK isn't hard, don't make it hard to start with. Don't build it up as a big thing. There is a lot of scope to bring advanced techniques into it later. But your first few thousand miles is not it.

This is a much more useful level for the questions you're asking:
Awesome, thank you very much.
Thank you to all who have replied. I do appreciate it very much!
 

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Discussion Starter · #15 ·
Well, @DM5PAV, if you aren't trolling :) we can try to answer your questions. Much of what you ask is learned by doing and being sensitive to how the car behaves. A basic knowledge of how a gearbox works will help.

The ratio of engine speed to car speed is determined by the gear selection. The output shaft of the gearbox. manual or auto, is directly connected to the car. The input shaft is connected to the engine via the clutch. Between them is a secondary shaft which carries pairs of gear with different ratios between input and output. Only one of those pairs can be engaged at a time. Actually they are all meshed but only one can be active. A gear pair is made active by a set of special teeth, sometimes called dogs, which lock one and only one pair to the secondary shaft. The other pairs are free to spin on the shaft. To select a gear with a different output/input ratio from what the car and engine are doing at that time, two things have to happen.

First (and this is a simplistic explanation with a few details technically incorrect), the input shaft and all the gear pairs must be made to spin at a new rate to match the new gear choice. This is so that the drive dogs which engage the new gear don't grind when trying to mesh. All modern gearboxes have a lockout mechanism called a synchronizer or synchro (invented by Porsche, BTW) which prevents the dogs from meshing until they are spinning at the same speed. That synchro also provides friction between the input and output dogs to force them to the same speed until their speeds match. Manual "double clutching" (not to be confused with "double-clutch" as a gearbox type such as the PDK) is a way to "help" the synchro. Instead of de-clutching then pushing on the shift knob until it slips into gear, you de-clutch, shift into neutral, engage the clutch, rev the engine until it is right for the car's speed with the desired new gear, de-clutch, push the shift knob, then engage the clutch. You rarely need to double-clutch when upshifting because friction and oil viscosity in the gearbox make the input shaft slow down on its own, which is what the synchro would be doing. Downshifting however means the input shaft has to spin faster, so if you help it out you may be able to shift quicker. (Double-clutch gearboxes like the PDK actually have two secondary shafts, one with the odd numbered gears, one with the even numbered gears. Each has its own clutch but only one is engaged at a time. A computer pre-selects the gear on the disengaged shaft based on how you are driving, then it executes a shift simply by releasing one clutch and engaging the other. It's fast, smooth, and expensive.)

Second, even with effective synchros to make the gearbox internals work smoothly, the engine must be made to spin at the correct speed for the new selection or else when the clutch engages the car will lurch forward or backward and some amount of clutch slip will occur. That is what rev-matching does. And if you double-clutch as described above, you end up with the engine at the correct engine speed so rev-matching is implicit. The engine doesn't have to be spinning at exactly the correct speed for the car, and when starting from a stop a perfect match between car and engine speeds is impossible of course. But less clutch slip means it will last longer, and smooth shifting is always good for car stability (and for passenger state of mind). As with helping the synchro, rev-matching is more important for downshifting because you are usually braking as well as needing the engine to spin faster. When you are upshifting you simply lift off the gas pedal and the engine slows on its own.

Heel/toeing is a way to operate both brake and gas pedals simultaneously with the same foot. It lets you brake while rev'ing the engine for either rev-matching or the complete double-clutch operation. When I first learned it, I put my toe on the brake pedal because it fit the car's pedal layout and I could modulate the brake with ankle movement. Magazine articles described is as heel on the brake, which meant modulating the brake with knee flex, not a good idea IMHO at the time. As @Viv said, it is often done with toe and the side of the foot. Whatever. With modern gearboxes, especially with automatic rev-matching, it is unnecessary.

After all that, it should be obvious how to shift. You want to release the clutch with as little slip and with as little lurching as possible. The slower you release the clutch, the more time it spends slipping but the more gently the engine and car come to terms. So release the clutch quickly with the engine already as close to the correct speed for the new gear as you can get it. Clutch slip is unavoidable when starting out from a stop. Otherwise you try to make the engine spin at the right speed for any new gear, and then release the clutch as quickly as is compatible with smoothness. You learn by feel what works. The goal is to be smooth but also quick.
Definitely not trolling and I understand why you’d think that. I actually have a lot of enjoyment when I get a perfect up shift and realized that if I learned more about this I could probably do that every time and that would be really cool.

that led me to thinking, hey maybe there is more to downshifting than just slipping it into the lower gear, which is what I do.

watching a lot of videos on older race cars and how the gearboxes would grind like a mofo if you didn’t “heel to toe” and then again realized… what the heck is “heel to toe”?

anyway, I am going to thoroughly watch all these videos and I appreciate the responses here. Not trolling at all. Just someone having a bit too much time on their hands and having a lot of fun in their new car, getting a bit geeky is all lol!

👍🏻
 

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Well, @DM5PAV, if you aren't trolling :) we can try to answer your questions. Much of what you ask is learned by doing and being sensitive to how the car behaves. A basic knowledge of how a gearbox works will help.

The ratio of engine speed to car speed is determined by the gear selection. The output shaft of the gearbox. manual or auto, is directly connected to the car. The input shaft is connected to the engine via the clutch. Between them is a secondary shaft which carries pairs of gear with different ratios between input and output. Only one of those pairs can be engaged at a time. Actually they are all meshed but only one can be active. A gear pair is made active by a set of special teeth, sometimes called dogs, which lock one and only one pair to the secondary shaft. The other pairs are free to spin on the shaft. To select a gear with a different output/input ratio from what the car and engine are doing at that time, two things have to happen.

First (and this is a simplistic explanation with a few details technically incorrect), the input shaft and all the gear pairs must be made to spin at a new rate to match the new gear choice. This is so that the drive dogs which engage the new gear don't grind when trying to mesh. All modern gearboxes have a lockout mechanism called a synchronizer or synchro (invented by Porsche, BTW) which prevents the dogs from meshing until they are spinning at the same speed. That synchro also provides friction between the input and output dogs to force them to the same speed until their speeds match. Manual "double clutching" (not to be confused with "double-clutch" as a gearbox type such as the PDK) is a way to "help" the synchro. Instead of de-clutching then pushing on the shift knob until it slips into gear, you de-clutch, shift into neutral, engage the clutch, rev the engine until it is right for the car's speed with the desired new gear, de-clutch, push the shift knob, then engage the clutch. You rarely need to double-clutch when upshifting because friction and oil viscosity in the gearbox make the input shaft slow down on its own, which is what the synchro would be doing. Downshifting however means the input shaft has to spin faster, so if you help it out you may be able to shift quicker. (Double-clutch gearboxes like the PDK actually have two secondary shafts, one with the odd numbered gears, one with the even numbered gears. Each has its own clutch but only one is engaged at a time. A computer pre-selects the gear on the disengaged shaft based on how you are driving, then it executes a shift simply by releasing one clutch and engaging the other. It's fast, smooth, and expensive.)

Second, even with effective synchros to make the gearbox internals work smoothly, the engine must be made to spin at the correct speed for the new selection or else when the clutch engages the car will lurch forward or backward and some amount of clutch slip will occur. That is what rev-matching does. And if you double-clutch as described above, you end up with the engine at the correct engine speed so rev-matching is implicit. The engine doesn't have to be spinning at exactly the correct speed for the car, and when starting from a stop a perfect match between car and engine speeds is impossible of course. But less clutch slip means it will last longer, and smooth shifting is always good for car stability (and for passenger state of mind). As with helping the synchro, rev-matching is more important for downshifting because you are usually braking as well as needing the engine to spin faster. When you are upshifting you simply lift off the gas pedal and the engine slows on its own.

Heel/toeing is a way to operate both brake and gas pedals simultaneously with the same foot. It lets you brake while rev'ing the engine for either rev-matching or the complete double-clutch operation. When I first learned it, I put my toe on the brake pedal because it fit the car's pedal layout and I could modulate the brake with ankle movement. Magazine articles described is as heel on the brake, which meant modulating the brake with knee flex, not a good idea IMHO at the time. As @Viv said, it is often done with toe and the side of the foot. Whatever. With modern gearboxes, especially with automatic rev-matching, it is unnecessary.

After all that, it should be obvious how to shift. You want to release the clutch with as little slip and with as little lurching as possible. The slower you release the clutch, the more time it spends slipping but the more gently the engine and car come to terms. So release the clutch quickly with the engine already as close to the correct speed for the new gear as you can get it. Clutch slip is unavoidable when starting out from a stop. Otherwise you try to make the engine spin at the right speed for any new gear, and then release the clutch as quickly as is compatible with smoothness. You learn by feel what works. The goal is to be smooth but also quick.
omgosh jim so many words cant
 

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Definitely not trolling ... Not trolling at all. Just someone having a bit too much time on their hands and having a lot of fun in their new car, getting a bit geeky is all lol!
I didn't think you were trolling. I was just pulling your chain. And if you are feeling geeky then it is definitely worth knowing how a gearbox works.

(I rebuilt my GT6 and Spitfire gearboxes several times. You learn stuff when you get to see up close how one works. I've never seen the insides of a PDK but I did see a video about the VW double-clutch automatic. I imagine the PDK is similar. It's a marvel of mechanical engineering. Very clever.)
 

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I found @jimmuller post above excellent, well written, very informative, and I certainly enjoyed reading it. For a nerdy/geeky retired engineer like myself, understanding what makes things work always considerably helps me do things better. An example I cannot forget was in the summer of 1964 when I just could not dive off a diving board and do a roll even with the slightest indication of it being obvious what I was trying to do. 1964-1965 was my freshman year and that included two semesters, each with a 4 credit hour mechanics course. Second semester was dynamics and I learned all about a concept called conservation of momentum and I suddenly intuitively understood why tucking arms and legs in tight will cause a skater to spin faster, etc. In June of 1965, with this concept clearly in mind, I was able dive off the board and roll on the first try without it looking too shabby. Extending this concept to shifting gears, it does help me shift more appropriately visualizing in my head what is going on inside the machinery. But that is me and, I perceive, mostly not others that were not born with a slide rule sticking out their ass. My late wife was truly brilliant but she would have thought I was talking offensively dirty (not good dirty) if I tried to explain gear ratios, torque curves etc. She just intuitively knew when to shift and did a really good job of it, actually more gracefully than me. Same for my GF that frequently tells me to just tell her the time and not how to build the G-Ddamn watch. So, for some, like myself, knowing how the gearbox and other machinery work is necessary to work it correctly, for others (Like most people IMO) they not only could care less, they do not want to know.
 

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I found @jimmuller post above excellent, well written, very informative, and I certainly enjoyed reading it. For a nerdy/geeky retired engineer like myself, understanding what makes things work always considerably helps me do things better.
Thank you, @Barryng.
 
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