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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.
All new in box, never opened.
Nightforce ATACR
Model C661
$3k
Nightforce X-treme Duty 34mm Ultramount
1.5" Centerline
20MOA
Model A683
$225
Nightforce Tool Kit
Model A432
$200
I have a lot of stuff to sell, adding more daily on here. Guns, scopes, ammo, primers, powder, bullets, etc. I am making some big life changes right now so I'm liquidating a lot of stuff. NEVER thought I'd sell this stuff, but here I am!
I have 3 boxes of 500 ea for a total of 1500 bullets, all...
Selling my Bosch RA 1180 router table with matching Bosch RA1190 stationary stand. This ad is for the table and stand only. Router is NOT included. Table height with stand is 39" Comes with all these attachments included:
• Feather boards for the fence
• Clear plastic bit shield
• Aftermarket...
Just bought an AUG so I am looking to sell only, but if you have a trade in mind, I am open to offers. Worst I can say is no!
Transfer FTF ONLY at “A Cut Above Pawn” in Beaverton. You cover transfer/BG fees
This rifle has less than 600 rounds through it, do your research before buying.
Hello, got my hands on a different K98k and it is time to let this one go.
This is a bnz42 Steyr produced K98k. All metal matches including the stock and handguard which is serialized in the barrel channel(have not gotten a chance to get a pic of the stock serial yet). I am a guy who can really...
I have a very nice Yugo Mauser M48 (Caliber: 8mm Mauser) in its original configuration with all matching parts. This is definitely one of the nicest M48 rifles that one can find around. The rifle is also accurate for an old surplus military rifle. I was able to get sub MOA groups at 200 yards...
I have a set of Ruger Blackhawks with matching serial numbers. They come with a beautiful wood and glass display case as well as their respective storage cases with a lock/key(not for the cases) and original paperwork in each case. The glass isn't fixed into the case at the moment. You just need...
Hello All,
I'm selling a S&W Model 66 no dash 2 1/2" barrel, pinned and recessed, matching factory grips. One of the finest .357 revolvers to evre leave the Smaith and wesson factiory(in my opinion). Shoots like a dream. 1970s era classic that has become very difficult to find in good...
Hello All,
I have a gorgeous Finnish capture Tula 1940 Mosin Nagant 91/30 from WW2, blued bolt variation. Blued bolt Finnish Mosins are unusual and rare these days. The vast majority of Finnish captured Mosins do not have a blued bolt, it was not a common Finnish modification. According to what...
Sks Norinco with ammo
+matching numbers+
Choate traditional synthetic stock *installed (similar to original, very lightweight)
180 rds Wolf polyformance 123 grain HP steel case
20 rds Belom brass 123 gr
25 rds PPU soft point round 123 grain
10 OG stripper clips (the best)
9 reproduction stripper...
Shield RMS2, 4 MOA dot, glass lens with matching Dawson Precision Glock MOS serrated black iron sights. This optic mounts to Glock MOS plate #4 and is perfectly flush on doublestack Glocks. Original owner, excellent condition, zeroed once on a backup gun but has sat in the safe ever since...
In like-new/excellent condition. I'm also including a set of counterfeit Magpul MBUS sites. I didn't know they were fake when I bought them. They actually look and function great, but you can tell when you compare them side-by-side with real Magpul MBUS sights. Still great for a budget AR build...
I want to trade my Norinco SKS. Comes as shown plus one 30rd mag. 550 rounds ran through it. Functions flawlessly.
Looking for a .22 pump action rifle, we will split background checks
Also looking for completed AR uppers chambered in 5.56/300blk/9mm, I will pay for background check
For sale is a SKS I've had for awhile but only took it out once to shoot. It had some pitting on the top of the dust cover and on the top of the bolt carrier as seen in the photos, but the rest of the metal looks good.
I think it is all matching numbers, including the bolt which is not seen in...
Glock Store blue Aluminum Ext Mag Catch, unopened & weighted base pads. One of the pads has some marring on the front, the rest are in good shape.
Asking $40 for the lot, or trade for 9mm / 30-06 ammo.
FTF between Silverton & Canby, no shipping.
Purchased from a retired PPB LEO years ago and papered to me. Not a clunker, this is the famous high quality Stratford Conn first generation, pre 1975 production. Comes with the matching box, papers (registration cut out by original owner), aftermarket synthetic stocks (much nicer to shoot...
Selling two new/unused limited edition Opinels. These No. 08 and No. 10 models both sport matching INOX blades with a black oxide finish. The Wenge handles are a perfect match. It would be a shame to split them up. $SOLD
PayPal, Venmo, Zelle, and cash are all welcome. Willing to ship for...
Hello All,
For your consideration I have 1942 Lee-enfield No.1 Mk III GFI Rifle Grenade model (All matching serial numbers). This is the GFI (British controlled) India manufactured standard pattern Lee-Enfield No. 1 Mk III issued during WW2. The copper wire wrapping on the stock is in order to...
Had this in storage for a while. Great condition and reliable shooter, has tech sights TS200 adjustable aperture sight with adjustment tool, which turned the rifle from a fun plinker into a great iron sight deer rifle. Easily put back into original configuration with included parts (take down...