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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.
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. 10 million serial number range, uncommon "p" suffex. This SKS is a Military issued Type 56, not a lower quality later commercial one. Light wear on the stock. Milled...
Putting this up to fund a different project.
Matching 12/48 ROF Fazakerley made No.4 Mk1 rifle that went to South Africa. One of the last Mk1 rifles, before Faz switched to No.4 Mk2 production. .303 British of course.
Receiver, bolt, magazine are all origunal matching. Buttstock original to...
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. 10 million serial number range, uncommon "p" suffex. This SKS is a Military issued Type 56, not a lower quality later commercial one. Light wear on the stock. Milled...
I have a JAKL FDE pistol lower with the matching FDE brace they no longer sell it on their site. I put 100 rounds through it ran excellent no hiccups.
$180 cash buyer pays transfer fee and BC.
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. 10 million serial number range, uncommon "p" suffex. This SKS is a Military issued Type 56, not a lower quality later commercial one. Light wear on the stock. Milled...
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. 10 million serial number range, uncommon "p" suffex. This SKS is a Military issued Type 56, not a lower quality later commercial one. Slight wear on the stock. Milled...
Up for sale we have a Serbian Police turn in SKS Rifle in 7.62x39. This one was refinished in Russian Blood by David at Soviet Stocks. Overall I would rate it as "Good" surplus condition with regular wear and tear for rifles of this period. This rifle was originally purchased from Calssic...
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. 10 million serial number range, uncommon "p" suffex. This SKS is a Military issued Type 56, not a lower quality later commercial one. Slight wear on the stock. Milled...
Hello All,
Up for sale is a really nice condition early pattern 1965 Norinco SKS. All serial numbers match including the stock. This SKS is a Military issued Type 56, not a lower quality later commercial one. Slight wear on the stock. Milled trigger guard, full lug early style barrel. This is...
Very nice Savage Model 10 in 243 with a matching Nikon Coyote scope 4.5-14x40. Also have 350 rounds of assorted factory ammo.
$950.00.
Trade for a Leupold VX-5HD 2-10x44 firedot scope.
I'll probably regret this, however, I can't bring myself to fire it, never mind carry it, it's too nice, so I'll let someone else deal with that dilemma. Knife complements it nicely.
$1400, no trades, no mags if it's staying in WA (I'd throw in 10rdrs but I don't have any, sorry)
Sound Loan...
I built a set of twins and still need to find two solid fixed rear sights. Anybody have a set of gently used ones they would sell or trade? Know of a good sale going on?
Thanks!
((All matching numbers)) no box . 24" Barrel no dings no scratches, bore bright and shiny. And is marked Keng's import. Manufactured at the 416 polytech factory. It's a pretty rare gun Keng's only imported a very small amount of the 223 version imported. Included are one 5.56 mag, no box. What...
I am selling my P320 setup minus the FCU. It includes the following:
-Sig P320 AXG Carry grip module with factory G10 grips and upgraded hex grip screws
-Sig P320 Compact slide with all factory internals, 3.9” barrel, recoil spring, factory suppressor height night sights, optic cut for RMR...
WW2 M1 Garand in good to great shape. Probably saw combat or training.
Parts:
Trigger and housing: WW2 Springfield
Bolt: WW2 Springfield
Op Rod: Springfield
Barrel Springfield
Receiver : WW2 Springfield
No Import marks!
$1195 Real Deal WW2
Here is a 1918 DWM Luger P08 with all visible numbers matching available for sale with the original wood base mag, extra mag and leather holster included for $2999.
This comes to us from a former collectors estate that kept his firearms in a climate controlled room and kept them in great...
Handguard sold. Adams Arms piston kit with front rail block, mid length short strike piston rod with Adam's Arms bolt Carrier (no bolt). This is a .750 gas block diameter. $80 $70 for the piston kit, rod, and carrier. Pickup in Puyallup or Sumner. Will ship for $20.
Trade for a quality weapon...
For sale is my Microtech Amphibian Automatic with a blade date of January 2002. Black anodized handle with stonewashed blade. The bladesteel is 14-4CrMo, which is the standard steel for Microtechs of this era. The knife is in 100% unused condition with no wear or signs of use or handling...