Marconi 2440 20GHz Frequency Counter

Description

This equipment has been tested. Please refer to the tests/remarks section below for details.

SERIAL NO: 187237/070

MANUFACTURER DESCRIPTION:

The Marconi 2440 Microwave Counter provides three channel automatic frequency measurement from 10 Hz to 20 GHz in a small portable case.

Measurements and operational details are displayed as a 9-digit liquid crystal readout. Resolution to the full 9 digits is automatic or can be manually set for 0.1 Hz over the full range to 20 GHz. The display rate can be adjusted from 11 ms to 20 s independently of resolution, which is keyboard selected from 0.1 Hz to 10 kHz. The microwave acquisition time is typically 200 ms. giving fast response and measurement updates.

The ability of the 2440 to make measurements in the presence of wide FM and large depth AM modulations is an important feature for applications in the communications industry. Frequency measurements can be made with up to 30 MHz peak-to-peak worst case FM and 40% AM depth.

The 2440 also features automatic amplitude discrimination. This allows the counter to measure the large signal that is applied to one of the three input channels, at the same time ignoring other signals. In addition Channel A incorporates a switchable low-pass filter to increase the attenuation above 5 kHz, so improving noise immunity when measuring low frequency signals.

TESTS/REMARKS:

• Frequency Test
  • Channel A: 10KHz / 1MHz / 10MHz / 100MHz – OK
  • Channel B: 50MHz / 100MHz / 500MHz – OK
  • Channel C: 600MHz / 1Gig / 2.5Gig / 5Gig / 10Gig / 20Gig – OK
• Mains filter changed
• Channel A/B/C push switch buttons require many pushes to latch – all buttons work but stiff.
• Case/body in fair condition.
• BNC+N connects OK but slight wear.