Loop Current Booster+

  • Increases Loop Current to 27ma
  • Boosts on-hook talk battery by 24VDC
  • Polarity toggle switch
  • 1 Year Warranty
  • 30-Day Money Back Guarantee
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Unit Price
US$ 123.65
US$ 123.65
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The Loop Current Booster+ adds 24VDC to the on-hook talk battery. If the on-hook (hung-up) talk battery on a line is 24V, the Loop Current Booster+ will raise the on-hook voltage to 48VDC.

The off-hook DC voltage will be the same as any phone line with 27ma of loop current.

The Loop Current Booster+ will boost loop current from a CO line or station port providing as low as 15ma of loop current, at 20 to 48VDC.

The Loop Current Booster+ does not change the ringing voltage or current, and does not provide any audio gain. One Loop Current Booster+ is required per line.

Some phone companies no longer offer any conditioning for an OPX. They won't install repeaters or condition the line for you. The Loop Current Booster+ boosts the talk battery and loop current, so you can get many non-conditioned (or improperly conditioned) OPXs to work.

When used on an OPX (Off-Premise Extension), the Loop Current Booster+ is normally placed at the near-end of the circuit (where the dial tone originates). Modern phone system station ports typically have less than 48VDC talk battery, so placing the Loop Current Booster+ in-series between the station port and the telco OPX demarc will make the loop current and talk battery look more like a standard phone line to the phone company.

If there’s not enough loop current on a phone line or at the far-end of an OPX (below 23ma), phones will sometimes not work properly (they might have dialing and/or talking problems). When the Loop Current Booster+ is used in-series with the pair entering a premise, it increases the loop current and talk battery voltage. You may need a Loop Current Booster+ on each end of an OPX.

A Line In-Use LED indicator is located on the face of the Booster.

The CPE equipment (telephones) connected in-series with the Loop Current Booster+ will work without 110VAC power, but you will have no boost of the talk battery or loop current. It will simply pass the line through.

The Loop Current Booster+ has two switches. One switch (red button) is flipped on initial installation to match the polarity of the line. The second switch (white button) puts the Booster in either Loop Current Boost mode, or Battery Boost mode.

Use Battery Boost mode if the device supplying the dial tone/talk battery has internal current regulation. When in Battery Boost mode, the Loop Current Booster+ won't fight with the device's internal regulator (which would sound like distortion, motorboating, screeching or low volume).

The Loop Current Booster+ has modular connections for both the telephone line or station port, and the telephone equipment.

Includes 110VAC to 24VDC unregulated power cube. Do not substitute a different power transformer!

220VAC International Power Cube (#MON8M) is available.

Also available in a 25-Line Chassis version, contact us for current pricing and availability on the Chassis version.

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This product is shipped from our supplier's warehouse in Glendale Heights, IL, United States
Our guarantee
This product is brand new and includes the manufacturer's warranty, so you can buy with confidence.
A 25% handling charge is levied against all authorized returns except those due to our error. Unauthorized returns are subject to a 40% handling charge. Damages & defects must be reported to us within 14 days.
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