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Line Filter AC-7
|The NQN 7-amp AC line filter was developed for high-level RF
interference environments, where computer and monitor power-line noise causes a
sensitive receivers, as well as with critical listening and
recording environments such as high-end audio studios, home theaters, and
audiophile stereo systems.
The NQN AC line filter is especially effective in
eliminating the high-level AC line noise generated by the six or more
computer/monitor systems used by amateur radio operators during multi-multi
contesting. Also noise sources such as wall-wart generated RFI is a serious
station problem. To address this issue the AC-7 can be supplied with
an optional IEC-to-NEMA adapter so wall-warts and other equipment may be
plugged into it. See Price list to purchase this option.
The NQN AC line filter features the following:
- Line cord radiation is minimized by using a three-wire power line cord
having a foil shield and a drain wire.
- Nine (9) capacitors are used and are all AC-rated Class Y2 or Class X2.
- Four 52 uH Powdered iron toroidal cores (two per line) provide optimum
power-line differential-mode filtering and are rated for a maximum line
current of 7 amperes.
- The foil shields and third-wire ground are
maintained via the filter's aluminum case from the IEC female receptacle
to the NEMA three-prong male AC plug.
- The 115-VAC leakage current measured through a 1,500 ohm
resistor from the filter case to ground is less than 1.4 milli-ampere.
- The voltage drop between the filter input and output at a
load current of seven amperes is about 1 volt which is less than a 1% drop in the
115-VAC input line voltage.
- A three-prong female-to-two-prong-male adapter
"cheater" is included (with the AC-7 model only) if you need to break the shield ground at
your 115 VAC power receptacle to eliminate a ground loop via the shield.
- The cover is secured to the aluminum case with four 6-32 machine screws
into four 6-32 threaded holes in the cover that are provided by the
W3NQN AC Line filter - inside view.
|Compare this with a Brand "C" filter which only
handles common-mode interference problems. The NQN AC power-line filters
are optimized for
common-mode and differential-mode filtering and have about 3 times
the components of brand "C". Plus they are all rated for this
type of duty. If you compare the size of cores and windings of other
filters we think you will agree the NQN AC-7 power-line filters are of the highest quality.
Engineering that makes a difference in the
Several progressive contest stations have already converted to
the NQN AC power-line filters
to eliminate the computer generated noise. Shouldn't you? If you
have my SixPak which can isolate down to 85 db between stations, you will benefit
from getting rid of the PC and monitor trash. The next thing you need to
do is replace all your RF cables with double shielded RG142 to achieve that next
level of receiver "quietness".
Helpful for reducing background noise in your high-end audio system too.
According to Audio Expert Jim Smith,
system will love it".
(Click the image above to visit Jim's site)
February 2, 2012: Thanks to Jim Smith for recommending the AC7 Line Filter
in his "Quarter Notes" newsletter. The demand for these filters from audiophiles
is greatly appreciated, but as these filters are each custom-made with
hand-craftsmanship by Ed Wetherhold (the designer) himself, it may take a few
weeks to catch up with the order volume. We thank you and request that you would
be patient while your filter is built. - Array Solutions
Q: You have 4 different versions available, which model should I purchase?
A1: If you're outside the United States and will be filtering 200v to 220v or
so, the AC7-EU is for you. This filter has standard IEC connectors on it for
both input and output.
A2: If you're elsewhere, the decision comes down to whether or not your
equipment has an IEC connector on it, and if you want to replace the power cord
totally or place the filter at the equipment end of the power cord or at the
wall outlet end. The standard AC-7 (pictured above)
is designed to replace the entire power cord for your equipment that uses an IEC
A3: The AC-7B (shown here) is intended to install at the equipment end of
your power cord and has male and female IEC connectors/
|AC-7B with short
"pigtail" IEC cords
|| These are the IEC
connectors on the AC-7B
A4: The AC-7A is similar to the AC-7B with short pigtail leads but having a
"normal" (NEMA 5-15P) plug for your wall outlet and a similar "normal" socket (NEMA
|The AC-7A is outfitted with these connectors and would
install at the wall outlet end of your existing power cord.
At present, we do not offer filters with other connectors - e.g.; C5, C7.
Pricing and Ordering