My Celwave PD 497-1-1 VHF duplexer just can't seem to provide adequate tx/rx isolation (Micor 100 watt repeater with 0.6 MHz tx/rx separation). Everything else seems to check out okay; jumper cables, connectors, receiver, and hard line.
I inherited care of the duplexer within the past 2 years; I estimate it's probably about 25 years old. The operating environment now is a climate controlled cell site, although at one time I believe it was installed in a utility shed at a water tank.
I've heard the PD 497-1-1 isn't the latest in duplexer design and was wondering what other VHF repeater owners might recommend with regard to high performing, closed spaced duplexers for moderate power applications.
Thanks.
Tony
2 Meter Duplexer Recommendations?
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Re: 2 Meter Duplexer Recommendations?
The PD497, while not being the absolute best spec-wise, should provide plenty of isolation even on a 600KHz split. I would suggest finding someone who knows duplexers inside and out and can disassemble the unit, clean it out, replace the harness with a new one, and retune the thing completely.
If you want to look at a new duplexer, I'd strongly suggest EMR. Their people are great, you get to talk to a real engineer when you call in, and they'll turn stuff around quickly. They built and tuned a 6-cavity pass/notch with dual isolator for a fire repeater I maintain and had it to me inside a week (ordered Monday, delivered Friday) with no rush fees. They are also about half the price of Celwave... however, a 6-can with isolator rated for 150 watts continuous will still run you about $2500.
If you want to look at a new duplexer, I'd strongly suggest EMR. Their people are great, you get to talk to a real engineer when you call in, and they'll turn stuff around quickly. They built and tuned a 6-cavity pass/notch with dual isolator for a fire repeater I maintain and had it to me inside a week (ordered Monday, delivered Friday) with no rush fees. They are also about half the price of Celwave... however, a 6-can with isolator rated for 150 watts continuous will still run you about $2500.