here is a quick tutorial on using that particular SWR meter (Astatic PDC2):
1. connect coax from back of radio to "TX" side of meter.
2. connect coax from antenna to "ANT" side of meter.
3. set radio to channel 1 (26.965 mhz)
4. set top switch to "100W" position.
5. set bottom switch to "FWD" position.
6. turn mic gain on radio all the way down/ off.
7. key the microphone and adjust knob on meter until the needle lands directly on the right edge of the scale where it says "SET".
(on the left meter, this coincides with the number "10" on the watt scale)
8. unkey the microphone.
9. without touching or moving the knob on the meter, switch the bottom switch to "REF".
10. key the microphone and note the reading on the "SWR" portion of the scale.
11. unkey the microphone.
12. go to channel 40 (27.405 mhz) and repeat the whole process.
both readings should be less than 1.5. if they are, great, your antenna is tuned.
if the reading on channel 40 is higher than the reading on channel 1, then your antenna is a little bit too long.
try shortening it in 1/4" increments.
if the reading on channel 1 is higher than the reading on channel 40, then your antenna is too short.
try lengthening it by 1/4" increments.
if you cant get the readings below 2, then the antenna is still useable, but should probably be replaced with a better antenna.
if the readings are higher than 2.5 and you cant get them lower, then you might have an antenna problem that should be looked into.
as for the wattmeter portion of the meter, i cant tell if there is a switch that goes from "SWR" to "watts" mode, but there should be.
once you know you are in "watts" mode, you can use either of the 10 watt or 100 watt scales. (bottom switch in "FWD" position)
in the 10 watt scale, the number 1 is 1 watt and the number 10 is 10 watts.
in the 100 watt scale, the number 1 is 10 watts and the number 10 is 100 watts.
PS- i forgot to mention that the little antenna stays disconnected for all these tests. it is only used when you are doing field strength readings.
(nothing is connected to the meter and when you key the radio you will see an indication on the meter that will decrease as you get further from your antenna)
hope this helps!
LC
