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matching
In electronics, impedance matching is the practice of designing the input impedance of an electrical load or the output impedance of its corresponding signal source to maximize the power transfer or minimize signal reflection from the load. A source of electric power such as a generator, amplifier or radio transmitter has a source impedance which is equivalent to an electrical resistance in series with a reactance. An electrical load, such as a light bulb, transmission line or antenna similarly has an impedance which is equivalent to a resistance in series with a reactance. The maximum power theorem says that maximum power is transferred from source to load when the load resistance equals the source resistance and the load reactance equals the negative of the source reactance. Another way of saying this is that the load impedance must equal the complex conjugate of the source impedance. If this condition is met the two parts of the circuit are said to be impedance matched.
In a direct current (DC) circuit, the condition is satisfied if the load resistance equals the source resistance. In an alternating current (AC) circuit the reactance depends on frequency, so circuits which are impedance matched at one frequency may not be impedance matched if the frequency is changed. Impedance matching over a wide band will generally require complex, filter-like structures with many components except in the trivial case of constant source and load resistances when a transformer can be used.
In the case of a complex source impedance ZS and load impedance ZL, maximum power transfer is obtained when
Z
S
=
Z
L
∗
{\displaystyle Z_{\mathrm {S} }=Z_{\mathrm {L} }^{*}\,}
where the asterisk indicates the complex conjugate of the variable. Where ZS represents the characteristic impedance of a transmission line, minimum reflection is obtained when
Z
S
=
Z
L
{\displaystyle Z_{\mathrm {S} }=Z_{\mathrm {L} }\,}
The concept of impedance matching found first applications in electrical engineering, but is relevant in other applications in which a form of energy, not necessarily electrical, is transferred between a source and a load. An alternative to impedance matching is impedance bridging, in which the load impedance is chosen to be much larger than the source impedance and maximizing voltage transfer, rather than power, is the goal.
I'm putting a feeler out there for my beautiful pre-war K98k. It's a 1937 manufactured i block S/147 (J.P. Sauer & Sohn). No import marks or duffle cut. The rifle is 100% matching down to the smallest screw, meaning it's EXACTLY as it was the day it came out of the factory. It's beautifully rust...
I picked this great Mosin up a while back along with a few others but decided to only keep the carbines. This is a desirable hex receiver Tula from 1936. Like most Mosins, it is a refurb but serials all match with the only force match being on the magazine plate. It has a mixture of Izhevsk...
I am selling my 1938 WWII era Mosin Nagant 91/30 PU Sniper rifle
Hi everyone, this here is a beautiful rifle! All serial numbers matching, tons of factory stamps, super clear glass, and a beautiful finish on the stock. This rifle is a beautiful piece of history.
1938 Mosin Nagant 91/30 Izhevsk...
AC44 P-38, no import marks and matching numbers. Has one 60’s P-1 mag.
P-38 album
$875, No trades unless a Ishapore 308 or M96 Swedish Mauser in very good condition and a little cash. Located mid valley, I can meet in Salem. I sometimes make it up to Portland area, like tomorrow 4-03-21...
So I got this in a deal with a friend, I don't think I'm going to get to use it at all. Originally thought I would use it for salmon.
https://www.sageflyfish.com/product/saltwater/salt-hd - retail $950
https://www.sageflyfish.com/product/core/spectrum-max - retail $500
Rod is the 990-4 model...
I have a typical Norinco SKS, in great shape, matching numbers and 100 rounds of ammo. This one does not have the bayonet. $599 and the fees are on you. Thanks for looking.
From the Halcyon days of hand-select Mosins is this all matching original numbered 1943 91/59. NO renumbered parts, as from the arsenal, excellent ++ exterior metal and wood and excellent bright sharp bore.
Not to be found in the wild $400 ,buyer pays tfer fee.
Selling two rifles to fund home projects, including a like new Marlin 1895 TSBL "Trapper" and a rare Russian 1955r Tula SKS which seems original and is matching (no obvious signs of refinishing, no bead blasted rear sight, great original bluing, couldn't find any refurb stamps, no force...
Hello all -
For sale here is a Series 7 Type 99 made by Nagoya. This factory produced through the entirety of WW2. The bolt handle and body both match to the receiver. This looks to be a later war rifle as evidenced by the simplified safety grooves. It shoots smoothly with Steinel 7.7 Jap...
For sale here is a CZ52 chambered in 7.62x25 Tokarev (7.62 Tokarev). It is matching with CAI Import Marks.
It is missing a rear sight but functions fine and the condition is in really good shape. The firing pin is not damaged but as with all CZ52s, you should avoid dry firing it with the...
Norinco MAK-90 (AK47) Sporter comes with two sets of furniture, two 30 round mags and one 5 round, pin on and threaded brakes(barrel is not threaded), front sight tool, B Square scope mount, everything pictured comes with it. This is a square receiver, and all numbers match. Finish is very...
I have a Yugo with matching numbers and a very nice bore. A great shooter. Has a bit of surface rust on the bolt cover and the rear sight block but overall is in really good condition. Has a Tech Site rear peep sight installed, which greatly improved the shooting accuracy, and i have the...
I have a Yugo with matching numbers and a very nice bore. A great shooter. Has a bit of surface rust on the receiver cover and the rear sight block but overall is in really good condition. Has a Tech Site rear peep sight installed, which greatly improved the shooting accuracy, and i have the...
Where are my salmon and steelhead guys at? How about the waterfowl crew? I'm 6'3" 365lbs and a bit heavier on the topside. These are Togg's largest wader sized set and they're a little bit snug up top for me. The quality is insanely good. The best waders I've had on and they are right up there...
Selling my 1945 German DOT 8mm mauser. This mauser was assembled by the Czechs post war using remaining and new German mauser parts. These new parts include the stamped winter trigger guard and stamped floor plate. This is a force matched/matched mauser. The rifles were built for Ethiopia by...
Selling my 1927 Schmidt Rubin 1911 Carbine (K11). It is all matching with its original muzzle cap and sling. The bore is nearly perfect. The stock shows typical dings, dents, handling marks, etc, but has no cracks or splits and is snug. The bluing/bolt is very good with some edge wear...
Selling three Yugo M48 mausers. Two are all matching with all milled parts and their sight hoods and cleaning rods, and the third is an M48 with a stamped magazine plate and trigger guard with no rod or hood. Two original leather yugo slings are included. Condition breakdown:
Rifle 1...
Selling my 1944r Izhevsk M44 Mosin Nagant. It is all matching, no force matching except on the buttplate. First year of production for this iconic mosin. Baltic birch non-laminate stock. It is in good shape; the stock has handling and compression marks, dings, scrapes, and a few areas of...
Parting with my 1955r Izhevsk SKS. It is in wonderful condition with very minor nicks and scrapes on the matching Baltic birch stock. The bluing is deep and in exceptional condition with minor rub marks in some areas and a ding here and there. The bolt shows little-to-no tarnish or wear...