MFJ-834 RF Ammeter, 1.8 MHz to 30 MHz, Factory Display

MFJ-834 RF Ammeter, 1.8 MHz to 30 MHz, Factory Hamfest Display

MFJ has no more of these, but when they did, the price was $109.95.  Save 30% by buying this hamfest display model.

Here is how MFJ describes this ammeter:

Connect the MFJ-834 Coax In-Line RF Ammeter between your antenna and tuner/ transmitter/amplifier and measure antenna feedline current in 3 calibrated ranges. Use it for tuning your antenna tuner/ transmitter/amplifier for maximum radiated power, for determining antenna feedpoint impedance, for comparing antennas and tuners, for trouble shooting and for checking for changes.

Tuning for maximum feedline current for any given antenna always gives maximum radiated power! Any adjustment - transceiver or amplifier tuning/loading controls, antenna tuner settings, whatever - that increases feedline current improves power transfer and gives you a stronger radiated signal. Radiated power increases rapidly because power increases as the square of the current.

Minimum SWR does not always mean maximum radiated power,  your tuner or lossy coax may be dissipating power, and you may not get peak output power even if your tuner or amplifier is properly tuned. Use the MFJ-834 to determine best antenna tuner settings and to compare various tuners. Calculate your antenna feedpoint impedance by dividing your applied power by the square of the feedpoint current. Your antenna can change when you apply power as insulators break down, traps heat up, capacitors leak, and your feedpoint impedance may be drastically different from your SWR Analyzer measurements. MFJ RF ammeters are rugged, read accurately over 1-30MHz in three linear ranges (.3, 1, 3 Amps) and barely perturb the antenna.

Uses SO-239 connectors.

Measures 6" W x 3 ½"H x 4 ½"D

Large 3-inch lighted meter. Use 12 VDC or 110 VAC (DC power supply not included).

NOTE ABOUT FACTORY DISPLAY UNITS:

USED:  eBay requires items that have been used as retail displays to be listed as "used", even if they have never been sold. This item has never been sold or placed into service. This is a fully-functional unit that was used as a static display as part of MFJ's hamfest display booth. As such, it may have cosmetic scuffs or scrapes on the cabinet, it may have some extra, tiny holes (usually two at the most) in the cabinet from security brackets on the hamfest displays. Hamfest displays often had a "show sticker" applied to the cabinet. If so, those have been removed, and there may be some adhesive residue left where the sticker once was. Goo-Gone and rubbing with a thumbnail will usually remove all or most of the residue. The residue is a cosmetic thing only. Some case screws may be missing, or may be mismatched.

The photos here are of the actual item being sold, not "stock" photos. Please look closely at the photos, as those are the best guide to the cosmetic condition of the cabinet or case. If you'd like, you can always repaint the cabinet with readily available matte-finish black paint.

As a demo/display unit, there is no factory warranty, but there is a 30 day warranty from FatCat.Parts on items sold as Used. Warranty does not cover cosmetics, it covers only the functionality of the item. No factory packaging or paperwork is included.

On all demo/display units, what is being sold is what is seen in the photos. If it is not in the photos, it is not included, unless the listing specifies it is included.

The white strip that says "MFJ FACTORY DEMO/DISPLAY UNIT" peels off cleanly.

Ships safely and quickly from Mississippi.