NRM-2 Resonance Dip Meter

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National RF’s Resonance Dip Meter is a test instrument used to determine the resonant frequency of a tuned circuit or resonant network, such as an antenna system.  In addition, the unit may function as an RF detector, or a  secondary frequency source.  The instrument is analogous to the older vacuum tube “grid dip meter,” once popular in every electronic laboratory or radio station.  Unique to this updated version is a buffered output that may drive a digital frequency counter for exact measurement of resonant frequency, or connected to an oscilloscope to be  used as an RF detector and waveform/modulation  monitor.

The unit is hand-held and powered by a single replaceable 9-volt battery.  Battery lifetime is estimated to be over one year with average usage.   Plug-in coil sets are provided to provide a useful frequency range from under 1 Mhz to over 70 Mhz.  Each plug-in unit has its own separate analog scale which gives approximate RF frequency.  Exact frequency is determined by the use of an external frequency counter, not provided with this system. 

The instrument is offered in two configurations in order to meet your technical requirements as well as pocketbook considerations.  Type NRM-2D is the deluxe instrument set, including a ruggedized carrying and storage case (manufactured by Pelican Products) and the standard three coil sets, covering the 3.5 MHz to above 40 MHz frequency range.  Otherwise, the basic Type NRM-2 instument with one customer specified coil set is sold to the user.  The other coil sets may be purchased separately, as desired.  Additional coil sets are available to cover frequencies between 1 MHz and 3.5 MHz, as well as from 40 MHz to 70 MHz.  These sets are not provided with the deluxe instrument configuration, and sold separately upon request. 

                                                                   TECHNICAL SPECIFIACTIONS

                                                                    Type NRM-2  and  NRM-2D

 Size:   NRM-2 Mainframe Body   4 in. X  2.125 in. X  1.75 in.  (coil not installed)

            With coil assembly installed       6.75 inches, overall

            Frequency Range:         Coil Set A:   1 MHz to approximately 1.9 MHz

                    Coil Set B:            1.8 MHz   to  3.5 MHz

                    Coil Set C:            3.5 MHz  to  9 MHz

                    Coil Set D:            7.1 KHz to  19 MHz

                    Coil Set E:            17 MHz to 43 MHz

                    Coil Set F:            40 MHz to 70 MHz

             (Note:  Coil Sets C, D, and E are standard with the deluxe model)

              Power  Requirements:   Single 9-volt Alkaline battery

             Controls:   Main Tuning     RF output/power

            Interface: Buffered output via BNC female chassis jack to Frequency Counter  or   Oscilloscope, approximately  1/2 Vpp into 1000 ohms  

 Type NRM-2   (Main-frame plus one customer specified coil set)  $219.95

 Type NRM-2D (includes carrying case plus C,D,E coil sets)           $299.95

                                                                      Individual coil sets   $39.95

                               California Residents must add 7 3/4% sales tax.

                              Shipping and Handling extra, dependent on order.


Overseas Customers: Please note that an additional overseas shipping charge will be applied to your order. National RF will notify you of the exact amount of shipping to your country via e-mail, after your e-order is placed. The customer is responsible for all and any customs or tarrif charges applied to your order.


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