ASTM 201 304 Stainless steel coiled tubing suppliers

Acquiring an oscilloscope used to be a rite of passage for hardware hackers. Until recently, new tools were rarely within the average person’s budget, so you’re probably stuck with an old oscilloscope. There are plenty of inexpensive options these days, especially if you include inexpensive computer oscilloscopes and “oscilloscopes”. Digital meters are also cheap these days (they are often free in some large stores), as are signal generators, frequency counters, and even logic analyzers.

ASTM 201 304 Stainless steel coiled tubing suppliers

But there is one piece of test equipment that isn’t seen as often as it used to be, and that’s a shame because it’s a very versatile piece of kit. Admittedly, if you don’t work with wireless, it probably won’t be on your wish list, but if you do anything with RF, it’s not only a versatile tool, but also very valuable. what is it called It depends. Historically they were called “Grid Dip Oscillator” or GDO. You may sometimes hear it referred to as a “grid tilt meter”. However, modern versions don’t have tubes (and therefore grates), which is why you’ll sometimes hear them now referred to as inclinometers, or maybe just buckets.
Whatever you call them, the principle of operation is the same, and it is very simple. The instrument is nothing more than a very broadband oscillator with the output connected to an external circuit. There are also ways to control how much power the generator is using. This is usually done by looking at the peak amplitude of the oscillator.
The reason for the drop has to do with how the inductor and capacitor behave at different frequencies. There are three sources of impedance in almost any circuit or component: resistance, which should not change with frequency, capacitive reactance, due of course to capacitance, and inductive reactance of inductive components. In some cases, you have a lot of them. For example, carbon resistors should not have too much reactance of any type. Capacitors should be mostly capacitive.
For a given capacitor, the reactance is very large at low frequencies and very small at high frequencies. Inductance does the opposite: low frequencies produce less reactance than higher frequencies. This is easy to remember if you think of direct current as a wave with zero hertz frequency. An inductor (coil) will obviously carry DC (low reactance), while a capacitor (two parallel plates) will obviously not carry DC (high reactance).
Although the total resistance of the circuit depends on these three elements, it is not as simple as adding up the values. This is because resistance and reactance are not the same quantity. If you have a 1V signal going into a 2 ohm load with 3 ohm reactance, you want to know that it behaves the same as 1V going into a regular resistor. If resistance and reactance are connected in series, the value of this effective resistance is equal to the impedance, which is the vector sum of resistance and reactance.
So in this example 22+32=13. The square root of 13 is exactly 3.6, so the impedance is 3.6 ohms. To further complicate matters, inductive and capacitive reactance tend to cancel each other out. Capacitive reactance is usually considered negative, although since we’re squaring it, it doesn’t matter what kind of negative resistance you take into account for this particular calculation. For those who are mathematically inclined, you really think of resistance as the real part and reactance as the imaginary part of a complex number. Converting to polar form gives magnitude and phase angle.
The parallel connection is about the same, but the reactance increases in the same way as the parallel resistors. But the fact is that at certain frequencies, inductive and capacitive reactance are equal. In a series circuit, this means that the reactance becomes zero and only the resistance remains. In a parallel circuit, zero ends up in the denominator of the fraction, so the effective reactance is infinite (and when a pure resistor is connected in parallel, it does not change the value of the resistor). In either case, the reactance cancels out, leaving a pure resistance.
The point at which reactances cancel each other out is called resonance. The inclinometer works because at the resonance point, the meter’s oscillator will see the maximum load (lowest impedance), so the voltage will drop (or drop). At any other frequency, some reactance will remain and the total impedance of the circuit under test will be higher than at resonance.
Obviously, the main function of the inclinometer is to measure the resonant frequency of the circuit. If that’s all it takes, it’s very helpful. But with a little extra effort, an inclinometer can do a lot more.
First, it can also measure other tuned circuits, not just component capacitors and inductors. For example, antennas, crystals, and transmission lines may have a specific resonance point, and a meter can measure them. For crystals, the frequency is the oscillation frequency of the crystal (with some error depending on the load capacitance and other factors). Antennas can resonate at multiple frequencies, not just the one you’re interested in, so some judgment is required. Anything that doesn’t have a coil (such as an antenna or a crystal) needs a small coil to transfer power from the meter to the circuit.
For power lines, you can measure this by making a small loop to connect the inclinometer (the smaller the better). Find the lowest dip and it will show 1/4 wavelength of the transmission line frequency. For example, if a cable resonates at 7.5 MHz (40 meters wavelength), the cable is about 10 meters long. However, do not forget to consider the transmission line speed factor. That is, a quarter-wave transmission line with a rate factor of 0.66 will be shorter than the theoretical length (in this case, it is only 66% of the theoretical length).
Of course, you can use the transmission line ratios however you like. That is, you can get the resonant frequency to measure the cable, or you can set the frequency and adjust the line for slope. In fact, using what you know to get what you don’t know is often a good principle for grid inclinometers. Want to measure an unknown capacitor? Make it resonant with a known inductor. Or start with a known capacitor and find the value for an unknown coil.
However, one of the main problems is a reasonably accurate frequency reading. Some modern sensors have digital displays (such as the DipIt shown on the right). However, the most common pressure gauges do not. On the other hand, you can easily connect them to a frequency meter or use a receiver to accurately determine the frequency.
More measurements are available if you don’t mind some estimation. Coils have a Q (Q factor) which indicates how much resistance they have in relation to their reactance. Use a good reference capacitor, form a resonant circuit and rotate the meter. Pay attention to frequency. Then turn down the inclinometer until you notice how often its reading is about 30% higher than when tilted. Now raise the tilt sensor and go down the slope again until you find the 30% mark again on the other side. Q is approximately equal to the lower frequency divided by the difference between the two 30% frequencies.
This may be obvious, but Ursa Major can also be used simply as a signal source. For example, to repair a radio, you must set the inclinometer to the frequency you want the radio to hear and track it through the circuit. Many inclinometers also have a mode where they turn off the oscillator and use the coil (and tuning capacitor) and diode as a wavelength meter. The meter then displays the RF energy level at the tuned frequency. Some sensors even have headphone jacks so you can listen to the signal (making it almost like a crystal radio).
One of the reasons many people don’t have inclinometers today is that they aren’t as readily available as they used to be. Heathkit is a very popular supplier of inclinometers of various models. Other popular vintage models (often seen on eBay) are Eico, Millen, Boonton, and Measurements Corporation (be careful, if you’re not a collector, tube models may not be very profitable). You can find a list of many GDO images on the [n4xy] site (the images are a few clicks away from the next button on the main page). On the left is a photo of my old GDO Measurements (and yes, it uses tubes).
You can still find new inclinometers from MFJ (they sell the MFJ-201 shown on the right and you can also convert some of their antenna analyzers into usable inclinometers). There are also many programs on the Internet. If you want a real tube mod (not recommended), [w4cwg] has plans. [SMOVPO] introduces a more modern FET design with a new jumper to help make the drop deeper.
On the other hand, it seems shameful to build a new unit without a digital display. Of course, you can add one, or use a built-in one like DipIt or ELM. There are many other items and even kits. Look around. The hardest part is usually winding the coils, although some will require variable capacitors that are hard to find. However, in practice, any oscillator that can be stabilized will do. In fact, I have two old Heathkit buckets that used negative resistance tunnel diodes as oscillators (one of which is pictured on the left).
If you need a video demonstration of using an inclinometer, I couldn’t do better than [w2aew], so you can find his video below.
One of them has been on my “wish list” since I got my radio amateur license in 2008. I haven’t found a price I can afford yet. Also, I’m curious what shops are giving away digital counters? I can use some super cheap DVOMs to display mains voltage (I would never trust a cheap meter for anything else).
Harbor Freight often produces very poor sensors. Sometimes I take them and put them on the table, because about once a week someone comes in and asks, “Do you have an ohmmeter?” I just give them one and don’t expect it to come back. The only problem is that I don’t have a buzzer. This is complete nonsense, but for distribution …
Thanks, I’ll take a look. I have a couple of Fluke meters and even an old HP 3457A that I rely on to get correct measurements, but it would be handy to have a couple of cheap meters as low voltage monitors in my various power supply projects.
I have found that automotive magazines such as Hot Rod, Car Craft, etc. often advertise Horror Fright next to the back cover. Their cheap counters usually come with a “free” coupon ($10 to purchase). I love them, I have about a dozen of them, one for each machine, one for my desk, one for my workbench and about 5 more in stock. For 5 or so years I “collected” them, if I noticed any problems, it was only this summer. Doing something (I can’t remember what) the reading (either DC voltage or resistance) would disappear after a second or so. “Blank” means the reading is reset and goes to 0.00 or OL. I tried replacing the battery with another 9V battery that I had lying around, but it gave me a Lo Batt warning. When I put in my own battery, it worked fine. Horror Fright also sells another DVM for about $25 (I bought mine for $20). I carry it in my backpack, but the tilt-adjustable LCD sometimes doesn’t work in the horizontal position. I also have 4 Flukes.
Off topic, this is not about multimeters at all, OL means overload, which is normal for resistors, not observed at all, called infinity and normal volts, which means too much voltage in the selected range, the instructions for your device cover this. TM in real time? Above is the inclinometer grid. only.
I checked out a couple of red Harbor Freight counters I got for free with coupons. Terrible design, I wouldn’t use them in high power circuits. Solder balls and threads are everywhere, and the fuse is just glass. There is no fuse at all on the 10A input, non-standard banana jacks, the wires are too thin for 10A, and the insulation is too thin for the claimed 600Vac/1000Vdc.
My friend didn’t look at his meter until he checked the dryer’s 240V outlet. He plugged in another 10A wire and the meter exploded. I mean literally a very loud bang, a flash, and the two halves flew apart. Luckily he wasn’t holding it, lucky the wire he was holding didn’t melt.
I think I bought mine for $15 at some humfest. If you google, there are also many projects on the internet that use FETs to build them.
You can buy a DMM for £5 from Maplin in the UK. Maplin is an electronics supplier with a good reputation for low prices! Previously, they mainly sold components. The nearest branch to me is in a shopping area outside the city, the Maplin area is probably half a football field, and it has no more than 2 transistors of each type. For example 2 transistors. Two, separate transistors, 2 bases, 2 collectors, another. The rest can be ordered at the branch.
It’s a little pitiful. The rest of the store is filled with Chinese stamps, you can get better and cheaper stuff from the right consumer goods places, as well as novelty gifts, Chinese toy quadcopters and the like. The quality of all is very cheap, but the retail price of Maplin is very expensive.
I think like Radio Shack before The Fall. Sad to love Maplin, their annual component catalog was like teenager porn. 500 pages or more, huge list of components! Now it’s all crappy PMR walkie-talkies and outdated PC motherboards for 60% more than you would pay from an independent vendor. But for some reason there is no mobile phone. This is still mostly the prerogative of specialty phone stores.
In any case, I would say that even such a bootleg title would sell multimeters for £5, except that Maplin killed my dreams. Elsewhere, it could be a chain of DIY stores. Or, of course, online. You can get a multimeter very cheaply. Sometimes they are called “household electrical testers” or something so that the more expensive meters do not look very expensive. I’ve had a few inexpensive ones over the years and have no complaints. Often a transistor tester is also built in. In fact, there are more expensive things. I don’t know what the difference is. I want a quality build. Mine never knocked, so for many years everything is in order.
Other than that, if you just want to mount something on your PSU, you can also get LED Voltmeters/Ammeters on Ebay for a very low price these days. Usually just a PCB without a case, whichever way you like to mount it. Color of the 7-segment LED of your choice (yes, you don’t have to choose blue!).
Not exactly free, but enough to afford. I figured if someone was giving them away for free, it would be one for every customer, and only if the purchase was correct.
Now you can do better. Arduino can scan the DDS pin. The AD9851 operates at up to 60 or 70 MHz. Higher frequencies can be achieved with frequency doublers and triplers. Logarithmic power detectors can measure signals over a very wide range of power and frequency. Intelligent LCD touch display to display the frequency response.
Here’s a video with great info, I think I’ve seen it before, just happened to stumble across duplexers/cavity filters through YT AI and I kind of… came up with this reticle angle meter:
gosh I’m obviously not a hacker at all. I don’t remember ever hearing about an inclinometer (I did my first electronics project over 50 years ago – it was a quartz receiver – no batteries, just a long wire sticking out of my bedroom window to turn the air) That’s why I I’m reading Hackaday, for new learning… luckily I don’t have to use it. Things like working with the ESP8266 IOT kept me busy and didn’t break into new territory. In any case, thanks for a very interesting post.
Well, I have a few, but if you’re just starting out and want a tool that actually works, you probably don’t want to deal with lamps and bulky internals when there are great solid state alternatives. Now, if you’re collecting, it’s different.
The tubes wear out over time and also, to my knowledge, behave erratically as they use filament wire and build up deposits. Combine that with having them on an older device and the result might not be what you want.
Your theory about the tube is largely wrong: the “filament wire” (correctly called filament) is not affected by deposits. This is a misconception, you are confusing the details anyway, the transfer tube suffers from cathodic stripping at high voltage, not delivering proper heater current in the first place. This does not affect the receiving tube. Secondly, if you use the meter, I welcome you, the lamps can last more than 5000 hours. I have test equipment from the 50s, universities and labs with primitive lamps. After all, there are no downsides to tube inclinometers, some argue that vacuum tubes are actually better at detecting tube tilt than minority or tunnel diodes due to tube cutoff characteristics. I suggest you go for a cheap tube with an analog gauge, and if you decide you need the bells and whistles with a digital display, go for it.
I have a Measurements 59 inclinometer that I recently restored to like new condition. I installed an SMA connector on one side of the oscillator case and a “sniffer” inside next to the 955 oscillator lamp. My StarTek digital meter accurately shows the resonant frequency of my trap antenna or any other inductor when a dip occurs; its original analog scale is still amazingly accurate. Not bad for a 70s instrument that is very easy and enjoyable to use…
The lamps make simple GDOs and I’ve never had a problem with external power supplies. If someone can dig up Nuvistor, it will make a small package.
Some of the problems with solid-state “GDOs” are that bipolar transistors are not the direct equivalent of tubes, and early transistors definitely lacked gain and higher frequency response. I don’t know how well the Heathkit Tunnel Bucket works, but it’s another piece of equipment. So many rear cameras use other methods to see the drop. FETs appear like low voltage tubes, the gate drops like a grid, MOSFETs appear, it should drop too, but you can often see an RF detector to see the drop. In late 1971, the guys at Millen described using MOSFETs to turn their famous GO into a salable state element. The same chassis, coils and trimmer capacitors. All of a sudden, the “simple” tube circuit required a lot of work, including multiple RF chokes, to get it set up without false dips.
I’ve never built, but the tubes seem to be simple and the ones for sale are more complex.
I think GDO disappeared due to other test devices. But the price has also gone up. Heathkit or Eico are cheap and the closest ones are in the hundred dollar or more category.
Maybe in hobbyist circles, but tubes are still very heavily used in high power TV/UHF and microwave/satellite applications… #NotAllTubes
You can view this statement. http://spectrum.ieee.org/semiconductors/devices/the-quest-for-the-ultimate-vacuum-tube
In my experience, vacuum tube spoons are *better* than solid spoons. My Eico is fine, as is Millen Dipper. Hit transistor ladles are just average, their tunnel ladles are bad. So as long as you find one that works (or one you can fix), age shouldn’t be a factor.
A good ladle can “feel” the resonant circuit from a few inches away… it doesn’t need to be connected directly to the coil as shown in the video. Also, the meter should be relatively stable as you tune from one end of the range to the other. Poor people tend to have a lot of false positives.
The Big Dipper helps to reveal what is *really* going on in the chain. Every capacitor has an inductance and every inductor has a capacitance. This means that they naturally vibrate at a certain frequency. Also, your bypass capacitor becomes an inductor, so it’s worse than useless! The Big Dipper can also show that your circuit has spurious oscillations at unexpected frequencies, or that it is unusually sensitive to RF at certain frequencies.