We have volt-meters, ammeters, and ohm-meters, but none that I’m aware of for inductors or capacitors….
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Thx for the website info. I still have LOTS to learn!
Here is a cheap one listed on EBay: Digital meter
It's not mine. I don't have one and have never used one. Didn't know they existed until just now.
There are quite a few listed on EBay
I may have to buy one 
Search on "LCR Meter" and you see lots of them. They have been around longer than I have been doing this stuff and thats coming up on 50 years.
Pete
An ammeter is a coulomb meter. One amp equal a flow of one coulomb per second.
Obviously, you'll want to know how many electrons are in a coulomb: "The elementary charge is 1.6021766208(98)×10−19 C. One statcoulomb (statC), the obsolete CGS electrostatic unit of charge (esu), is approximately 3.3356×10−10 C or about one-third of a nanocoulomb. One coulomb is the magnitude (absolute value) of electrical charge in 6.24150934(14)×1018 protons or electrons."
From answers.yahoo.com.
You should adjust the gizwakometer on a Lionel loco to take this into account.
Also the basic unit of capacitance is Farad, not Coulomb. lemme see, q = CV, so C = q/V, so 1 Farad is 1 Coulomb per Volt. So you weren't too far off.
Just curious, what are you going to use the henry meter for? Worked in elec development many years and they are not that common. The only use I had for a capacitance meter was to match some capacitors. Not that the meter could tell me the ultimate accurate reading, but only that it gave the same reading for two different capacitors which was what I needed. I always found the hfe function much more useful in home projects.
One of the Radio Shack multi-meters I had in the mid 90's measured capacitance (though if I recall, the range wasn't terribly wide).
It also measured frequency, but only up to a few kHz, IIRC.
-Dave
First off, I see no relevance of either type of meter in Model railroading. Both would give you pretty accurate reading for each type. A "Henry" meter is used to measure induction coils, and the primary uses would fall into two areas. These two are "Amateur Radio" - and secondly in the old Copper wire side of Telephone cables. I have had experience in both, and have used an expensive HP 'LCR' bridge in the past.
The obvious answer for the capacitance meter is to get an accurate value, and also good when trying to match capacitors. Today's technology and design have made the prices of 'modern' LCR meters very affordable. The advancement into the digital world with fiber optics, have made the old equipment obsolete.
Either type of meter in the modeling world of toy trains is zero, in my opinion.
I have a pretty high IQ and am well-educated, but I swear I wondered if these posts were in English for most of them.
I have found that I have never been able to 'get' reading music and understanding what it means, as well as electricity and anything other than pos/neg/ground. God knows people have tried to explain it to me, and it's crazy simple for some folks*, but I just don't get it.
*people always think that whatever comes easy for them, must be equally easy for anyone else. There are plenty of things I got right away and seem second nature that plenty of other people will never be able to grasp... I guess we all have that one thing that doesn't make sense to us, but makes sense to most others.
P51, I can understand where you are coming from. Some people become proficient in various subjects, and can't grasp other ideas as easily. I spent 41 years with Ma Bell (Verizon) as a Cable splicer, in the Maintenance side as a troubleshooter. I went to whole gamut from (POTS) plain old telephone service of the old copper cables, all the way through to building, maintaining, and installing fiber optics, which take you from an Old Analog world to the Digital World. POTS lines using copper cables were manufactured to specific designs, and were fairly standard as far as electrical characteristics. The typical copper cables measured .083 Microfarads per mile of cable (26, 24, 22, gauge wires). A set from 19 ga. was in the range of .062-.066. These constants were necessary for good Voice communications. The typical voice range of the human voice is from 300hz-4000hz. A cable that was too long with strictly a capacity value, would affect the high range.
I used to ask other guys I worked with, what a Load Coil was, and how was it used. The 'Load Coil' is an inductor, or coil of wire wrapped around a ferrite core, and in telephone use, they all measured .88 millihenries. The majority of answers were that it amplified the voice. NO, NO, not at all. I would explain it with an analogy actually using Railroad Tracks, in the explanation. POTS service used a pair of wires called Tip & Ring. If a cable exceeded 18000 feet in length, it needed to have "COILS' added in specific spots. The railroad tracks were one rail was the TIP, the other rail was the RING, and if you stood between the two rails, on flat level even ground, what do the rails look like at the far end. Your range of eyesight makes it look like the rails are coming together. So effectively a cable too long "SHORTS" out the circuit. Excess Capacitive reactance, which can only be balanced or cancelled out by placing Inductance into the length. Once the analogy was used, they understood the basics of good old POTS service.
Bring on Fiber Optics, and the digital world, and it is a whole different ball game, but the underlying concept is 1 & 0, which is also known as ON or OFF state, and it goes into Binary Progressions, or multiples. (1-0-1-0-1 and then 11-00-11-00, 111-000-111-000, and so on.
p51 posted:I have a pretty high IQ and am well-educated, but I swear I wondered if these posts were in English for most of them.
If you don't want to talk electricity, you're in the wrong sub-forum. 
gunrunnerjohn posted:p51 posted:I have a pretty high IQ and am well-educated, but I swear I wondered if these posts were in English for most of them.
If you don't want to talk electricity, you're in the wrong sub-forum.
Fair enough. I read the new posts from the right-side of the site, so I rarely know what sub-forum they're originally coming from. Most of the time, I never notice it at all unless it's something like this...
Michael T: Thx for correcting my 'boo-boo' !
Dave: I HAVE one of those meters....And it DOES measure milli & micro farads! I just never noticed that until today!
I used to use a capacitance and megohm meter at work for testing high voltage capacitors. That thing was crazy expensive and would give you an insane jolt if you weren't careful . I've got a fluke meter and a craftsman clamp meter that both measure capacitance and I never use em for testing capacitors, so I don't see the need to buy an expensive piece of equipment I would never use. If I question the quality or functionality of a capacitor in my choo choo I just replace it cuz they're cheap. Now if your looking for a piece of electrical equipment you'll use, buy a scope
"Just curious, what are you going to use the henry meter for? Worked in elec development many years and they are not that common. The only use I had for a capacitance meter was to match some capacitors. Not that the meter could tell me the ultimate accurate reading, but only that it gave the same reading for two different capacitors which was what I needed. I always found the hfe function much more useful in home projects."
Well, AUSSTEVE, I'm running up the EE learning curve. That's the general answer. In this particular case, I'm trying to understand the 4 ckts in a Lionel 167C Whistle Controller....a real interesting PW gadget. After I've solved all the eqns that describe, quantitatively, the ckts, I want to know what approximations I can make to better-understand what's going on....So, in parallel, I'm trying to FIND a 167C to make some measurements. The KEY component is the "choke coil", whose inductance I'd like to measure.....AND whose function I'd like to understand!
BTW, What's the "hfe function"?
This thread is a stitch. Maybe we should start a forum on power factor correction and add capacitors to reduce volt-amps reactive? Remember X=2*pi*f*L if you get the henries measured. And don't forget inductive is a lagging power factor!
Just curious, what are you going to use the henry meter for?
A toy, just like all those trains.
Couldn't a henry meter be used to determine the inductance of just about anything, from a light bulb to an AC motor?
Almost all of my knowledge of electricity, beyond basic schooling is self-taught. I thought inductance could be thought of as the equivalent of resistance in an AC circuit. I understand that the formulas are more complicated than Ohm's law. Is that so?
I use my LCR meter to read small ceramic caps (<100 pf) where the lettering is worn off or hard to read. Also to read inductors when I am too lazy to look up the color code. We have researchers who use it to select caps when building finely tuned circuits. Not something that gets much use.
I don't think I have ever used it for train related projects though.
Pete
I use my inductance meter for unmarked choke coils, makes it handy to figure out what I have.
Interesting bringing up those formulas that I have forgotten. Once I went into digital design things like inductance, capacitance and resistance went by the wayside for the most part. It did come into play as processor speeds got higher the we dealt with propagation delays due to the above factors, so had to watch trace layouts to insure buss signals arrived simultaneously or didn't "jump" to adjacent traces and cause interference. At higher speeds things begin looking like RF signals.
And working in telco right after college I dealt with loading coils etc but didn't really understand them until going back and getting engineering degree and the professor briefly talked about loading coils before jumping to the math of why they worked. Nice to see a practical use rather than dry abstract math of inductors. Ditto of why high tension 3 phase lines are periodically transposed to minimize capacitance as I recall.
Surprised no one has brought up ELI the ICE man yet.
Would a Smith chart scare people away?
-Dave
I bought an O'Henry meter recently, it's great for finding candy bars.
Just sayin'... 
Here is a very nice unit very cheap. I will test transistors, read capacitance and inductance, resistance etc.. I have one and it woks great!
<Bring on Fiber Optics, and the digital world, and it is a whole different ball game, but the underlying concept is 1 & 0, which is also known as ON or OFF state,.>
50 years ago and in a galaxy far, far away while working at Bell Labs I was involved with the development of digital telephony. Those digital 'ONES' are actually analog. You can't just turn 'ON' for a 'ONE'. Due to capacitance and inductance you don't know what the heck will come out at the other end. So the transmitted 'ONE' is specifically shaped by a DAC (digital to analog convertor) so it will be received as and recognized as a 'ONE'.
