JJJelectronics- Signal strength meter ( S-meter)

*S-meter is a signal strength meter for use with any receiver. It is an audio driven meter. *Sensitivity: adjustable to allow readings to be set to user liking* can be used after the diode detector on 455KHz stage of Superhet radio receiver or after product detector* can be used after the mixer on direct conversion receiver* Voltage 10v-13.0v*Panel meter *You can add back light to the meter from the top or the sides of panel meter Panel meter and wires are included with the kit

Tool required.Soldering iron (25w-40w), small cutter, trimming tool for L8

Now let’s build the s meter

I would recommend fitting the parts in the order they appear in the part list.Resistor first, then semiconductors, coils and Capacitors.Make sure you put the electrolytic capacitors and diodes in the right way round .keep all components leads as short as possible.

When you have finished assembly of the board, check all the parts are in the right places.The soldering looks bright and good. Re-solder any suspect joints with a little fresh solder, check that there are no short or splashes of solder between tracks. Resistors

R1, R4, R5, R7 33k 4

R2, R3 10k 2

R6, R8 2k2 2

R9 22k 1

R11 Short, use wire link 1

R12, VR, trimmer resistor 1

R13 See note 1 1

R11 is short, use wire link instead of resistorTransistor, Diode and IC

IC1 8 pins chip 1

D1, D2 ,D3 1N4148 3

Capacitors

C2, C4, C8, C9 100nf 4

C3 Brawn capacitor 1

C5 See note1 1

C6 See note 1 1

C6, and C5 are electrolytic capacitors and must be installed the correct way round. The Longest lead is normally positive; this lead should go to the hole marked“+“ on the circuit board.

NOTE 1 :You will find capacitors values on a paper with your orderMiscellaniesPanel meter *wiresTesting *Connect a power supply to +10-14v and GND * Connect the s- meter to your radio receiver (you should take signal from the radio (from product detector or from the diode detector or from the mixer directly of the direct conversion receiver) (connect the radio signal to the input of the S-meter, pin 2 is signal and pin 1 is GND)*Adjust the trimmer resistor on the s- meter to give reasonable meter readings (or just put the trimmer resistor in the middle)