I found a 330pF and dropped a slug into L38, bingo! I get a pep of 18-20W from a 4W dk. Thanks for the guidance Brandon.
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Cobra 2000 L38
- Thread starter Cable Guy
- Start date
Maybe recheck the harmonic trap just to be sure. The last guy was after wattage. Not sure if you have an SA, but you can try adjusting that trap to the dip (not peak) in output wattage. Don't worry, it won't cut down on the 27MHz signal strength. The watt meter sees both the fundamental and harmonics. The trap only affects the 2nd harmonic (with the original parts anyhow), so tuning for a dip in power there is how I would do it without a SA.
Edit: or a TV or other 54MHz receiver, its hard to see the effects on a watt meter when the harmonic is more than 20dB below the fundamental. Ideally it should be around -50 to -60 dBc. But if all you got is a screwdriver and a watt meter, gotta make due somehow.
Edit: or a TV or other 54MHz receiver, its hard to see the effects on a watt meter when the harmonic is more than 20dB below the fundamental. Ideally it should be around -50 to -60 dBc. But if all you got is a screwdriver and a watt meter, gotta make due somehow.
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Yeah, at first I tuned to the dip, then tuned for least harmonic using an sdr. Idk if a sdr is an acceptable substitute for the sa in this instance but I can see the unwanted emissions and reduce them. Im not chasing watts or swing, I don't even know what I will do with this radio, besides recapping and any updates per cobra, so stock is always a good starting point.
An SDR should work fine. I smoked mine having it connected to an antenna too close to my sirio827 a few years ago. Some day I will get another one.