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Date Posted by Category User IP

2017-04-16 (UTC)



DB Products extreme perfomance 220 MHz Duplexers -

Pictures and sweeps:

These are a 220 MHz duplexer made with 11" cavities from DB Products. These were pass cavities converted to Pass/Reject and then aligned as a duplexer. These are all copper cavities designed for high power combining and perform exceptionally well as a duplexer.

Real insertion loss is displayed above in the calibrated VNA sweeps of a test unit tuned to 224.3/222.7 MHz. Insertion loss will be better than 0.7 dB, and notch depth is >90 dB. In the example unit it's .55 dB insertion loss and -95 dB notch depth. The band pass characteristics are much higher and have a tighter response than typical duplexers.

This directly translates into greater power handling as less power is dissipated in the duplexers and they have a larger area to dissipate power over. At .6 DB insertion loss 150 watts input will be 132 watts output or only 18 Watts lost in the duplexer. In comparison a typical 4" unit will see 1.3 dB of loss; over 45 Watts lost as heat.

The price includes tuning on your frequency pair.

I can ship these, either assembled on a pallet or packed into individual boxes requiring some assembly. The individual box packing is shippable by FedEx/UPS.
Please understand this is heavy and will be packed using foam in place. It's not cheap to ship coast to coast or internationally. Shipping weight is about 145 LBS.

I have band pass cavities for 220 MHz and isolators available. If you need a combiner or custom filter soultion for your repeater, I can provide this. If you need to collocate on a TV channel 13 tower, a soultion with a pass cavity on TX and RX, including a dual isolator and rack on castors can be engineered custom for your needs at an additional cost.

You can contact me here or, 727 409 1194 in the USA.

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