Quote:
Originally Posted by GroundUrMast
Is CBLN still on the air on channel 40? If so, any consumer grade amplifier would overload.
If you consider only the top seven pending digital database entries, add antenna gain (about 9 dB), it looks like you will be delivering a total of +40 dBmV to the amplifier input. That does not account for any signal from FM or fire/police radio. The CM-7778 is rated for 23 dB gain on the UHF band, and a maximum UHF output of +50 dBmV... that's infers that the maximum input would be 27 dBmV (50 - 23). So, I think the 7778 will overload due to being over-driven by 10 to 15 dB.
Honestly, I think the CPA-19 will be on the edge of overload as well.
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CBLN has moved from 40 to 23 and also reduced power to 24 kW (85% reduction). After the change the signal is now so weak that we have trouble picking up CBLN.
That was my feeling, that 23 db was too much, but the seller claimed that overload shouldn't be a problem since we will have 150' of cable and a three way splitter so cabling loss will be around 14 db more than if we had the antenna hooked up directly to the antenna. BTW the CPA-19 was added to offset these losses, realizing the if not for these losses a booster wouldn't be needed.
Sine the pre-amp is really needed for the VHF range more than the UHF range. To eliminate risk of overload (and since the only week stations are VHF) can the joiner be added after the booster rather than before it?