Meters: Frequency Determining
Frequency Meter
56 - 64 Hz
(EQP) JBT34-FP-9L
Antique JBT frequency meter. Reed type. 100v - 130v, 56 - 64 Hz. In original leather case. Excellent condition. Meter is enclosed in a black bakelite case. Looks to be unused.
$195
Frequency Meter
47 - 53 Hz / 57 - 63 Hz
(MTR) 30-FHXX-14
JBT reed type frequency meter indicates cycles per second both from 47 - 53 Hz and 57 - 63 Hz. 50/60 Hz. 3-1/2" diameter. Fits 2-3/4" hole. 2-7/8" deep. Perfect for monitoring the frequency of your 115v or 230v ac mains from your generator or power company. Maintaing exactly 60 Hz is important for efficiency on US mains. 50 Hz in most other countries.
$109 each - $95 (3+), $85 (12+)
Frequency Meter
39 - 41 Hz
(MTR) 15-FH56Y13R
JBTfrequency meter. 39 - 41 Hz. 10 vac. 1-1/2" hole required. 2" diameter bezel. 2" behind panel depth. Scaled.
$85 each
400 Hz Transducer
(MTR) 3188
400 Hz transducer. Converts @ 0 - 115 vac, 380 - 420 Hz input to a 0 - 1 madc output signal to drive a standard panel meter. 10 - 32 stud posts in / out. 2-5/8" diameter x 3" high. Useful for any avionic or other 400 Hz power user to monitor line voltage.
$15 each - $13 (3+)
Frequency Meter
"Reed Type"
(MTR) FRAHM
Frahm frequency meter. "Reed type". Scale reads 58 - 62 CPS. 100 - 150 volts. 3-1/2" diameter bezel. Requires 2.8" hole. 3" behind panel depth.  LAST ONE! Chipped flange at screw mount. NEW.
$195
Reed Type Frequency Meter
50 Hz Only
(MTR) 31-FX50
JBT reed type frequency meter indicates cycles/sec from 48-52 Hz in 1 Hz steps. 3-1/2" diameter face.
$90 each - $82 (3+)
Frequency Meter
55 - 65 Hz
(MTR) MMI-10628
General Electric giant nuclear electronic frequency meter indicates 55 - 65 Hz. 4-3/4" wide x 4-3/8" high face. 4" behind panel. Fits 4" hole.
$345 each
AC Frequency Meter
340 - 440 Hz / 390 - 404 Hz
(MTR) 410-05498
Varo AC frequency panel meter scale reads 340 - 440 Hz / 390 - 404 Hz. 4-1/2" diameter face. Fits 3-1/2" hole.
$225 each
Frequency Meter
388 - 412 Hz
(MTR) 13217E3785
A&M sealed meter for use with external transducer. Scale: "388 - 412 Hz". Actual full scale = 100 ľa. 3-1/2" diameter face. Fits 2-3/4" hole.
$45 each
Panel Meter
30 - 0 - 30 Cycles Per Second
(MTR) 632-0712
JBT reed type frequency meter indicates cycles/sec from 48-52 Hz in 1 Hz steps. 3-1/2" diameter face.
$85 each
Meter / Transducer
400 Hz
(MTR) 400HZ
Mil-spec 380-420 Hz system includes separate transducer (631-16394) and Phaostron 3-1/2" meter (20690D1). Meter is 200 ľADC full scale.
$500 each