The item on this page is a Bird TPM with a 3-1/8” line section. 7/8” and 1-5/8” are also available and can navigated from the product series listed above. Information on product configuration can be found further below on this page.

• TPM7 - with 7/8” line section
• TPM1 - with 1-5/8” line section
• TPM3 - with 3-1/8” line section

The TPM is used to measure power signals in broadcast systems and is used directly in line with the system being tested. Its output provides a linear DC voltage output from 0 to 4 volts allowing for a wide variety of interface options.

Its in‐line calibration capability allows for greater accuracy in a single application (with an accurate power reference) and its integrated non‐directional coupler allows for signal analysis in minimal space requirements. The TPM is available in 7/8”, 1 5/8”, and 3 1/8” 50-ohm lines for FM, VHF, and UHF broadcast frequencies.

When combined with a Bird model 3140A4 or 3140A8 Transmit Power Meter (TPM) display, a complete adjustment system is achieved. The display supplies a visual indication of Forward and Reflected power being sampled by the inline TPM. Multiple TPMs can be selected (only one per channel setting) to give the operator an overall condition of the transmitter system.

• World Class first in-situ power measurement standard
• Calibrate during operation, while ON-AIR
• Never any need to remove from service which equates to no downtime
• Traceable to the National Institute of Standards and Technology (NIST)

Please note, the image below is for illustrative purposes and shows a TPM1 with a 1-5/8” line section. The TPM is also available in 7/8” and 3-1/8” with a variety of line section configurations to choose from.

• SOURCE - Connect to the source of the RF signal (transmitter side)
• LOAD - Connect to the load of the RF signal (antenna/dummy load)
• FORWARD - The forward directional coupler port. Terminate this port in 50 ohms at all times.
• REFLECTED - The reflected directional coupler port. Terminate this port in 50 ohms at all times
• TEST - A non-directional sample port. No termination is required.

Bird TPM power monitors are separated into three groups which can be navigated from this page. They are as follows:

• TPM7 - with 7/8” line section
• TPM1 - with 1-5/8” line section
• TPM3 - with 3-1/8” line section

At the top of each page, there is a drop-down menu where your individual TPM can be selected. These are sorted in alpha-numeric order, first by frequency range, then by subsequent configuration options.

Power ranges on the TPM are rated at low, medium, high, and very high. The chart below provides a breakdown of each.

Please note, for the best accuracy, pick the lowest power range that includes your maximum average operating power.

The 3140A is the standard display and power supply for the TPM. It comes in both 4 Channel TPM and 8 Channel TPM models. It fits in a standard 2U rack and requires a single 15V power supply (supplied with a panel).

• 3140-A4 (4 Channel)
• 3140-A8 (8 Channel)