EMRFD Message Archive 6520
Message Date From Subject 6520 2011-07-31 08:45:21 Ron McCurdy FW: [emrfd] low output IRF510 John,
Here are the instructions for a popular kit that uses two of the IRF510:
PA Idling Current Adjustment:
1. Connect an ammeter in series with the power lead that supplies 12 volts
2. Disconnect the microphone, or short it's audio output so that no audio is
the microphone amplifier.
3. Key the transmitter (use a dummy load please) and note the idling
4. Key the transmitter and slowly adjust R-91 until this current increases
by 50 ma.
Unkey your transmitter. Note the new idling current.
5. Key the transmitter and slowly adjust R-2 until the idling current
another 50 ma. Unkey the transmitter.
You might try that.