Diamond SX40C SWR-Power Meter for VHF & UHF Transceivers

The SX40C is a compact SWR-power meter. Featuring cross needle design for measuring SWR and output power simultaneously. Compact size makes it very useful for testing mobiles as well as base station installation. Works great for marine radio installations.

SX40C General Specifications
The SX40C Cross-Needle power meter combines two meters which indicate forward and reflected power respectively. It provides the direct read out of the SWR value from the crossing of two pointers.

Specifications:
Frequency Range 144 - 470 MHz
Input Impedance 50 ohms
Power Range 30W or 300W switchable
Note: 70% of the full scale for 200 MHz band.
Power Readings Direct read out
Note: For 220 MHz band, it should be calibrated by 70% of the direct read out.
Power Accuracy 10% at full scale
Min. Power Requirement FOR MEASURING SWR 4W
Input/Output Connector UHF
Dimensions 85W x 87H x 95D m/m

Setting Up:
Connect the TX output of the transceiver to the “TX” connector and the antenna to the “ANT” connector, both located on the rear panel of the unit. Use 50 ohms coaxial cable for the connections.

Precautions
1) No mechanical shock to be given to the unit as it employs precision meters.
2) Do not transmit with an antenna out of tune, or open condition, as it may burn out the meter by high voltage.

Operation
Be sure the power output range of the transceiver and set the LO / HIGH range accordingly.
LO / HI switch is depressed for high (30W to 300W) range, and out for lowest (3W to 30W) range.
Keying the transceiver, measure the required parameters as follows.
• Forward power ~ follow the forward scale and read.
• Reflected power ~ follow the reflected scale and read.
• Standing wave radio (SWR) ~ follow the SWR scale from the point of pointers crossing and read it out.
Note: In case of 220 MHz band measurement, both forward and reflected power to be converted with the following formula: direct read out in the scale x 0.7 = actual power.
Example: when direct read out shows 10W, it should be 10W x 0.7 = 7W.