HF High Power Band Pass Filter– SERIES S

High Power Band pass filters are produced in SKY SAT Communications, Montenegro, owned by Ranko, 4O3A.

They are build in two different power levels – HP 2500W and VHP – 4500 W. The decision for having band pass filters after the linear amplifier is simple – on that point filters will reduce wide range noise, as good as all harmonics. Also, with filter in antenna line you simplify filter switching system. Actually, you do not have additional filters switching. They are implementing in antenna lines. Some problems occur and have to be solved:
- Insertion loss will “eat” some part output power and will transfer it in heating of filter. But, with those well designed and built filters insertion loss is less than 0.4dB, heating will be negligible. - Dissipation in each section has to be equal. Otherwise, temperature can be very high in some of them. Filters are very narrow and will prevent interferences, even antennas are very close each other on the same tower.

Once, you have band pass filter after linear amplifier, well designed and reliable, you will forget about all the problems with interferences between the bands and strong harmonics. Six filters and you will not have to care about switching low power filters between the AMP and radio (two sets, at least) and coaxial stubs. Anyhow, in any contest station layout (SO2R, MS, M2) you have to distribute proper antenna on each radio. If filters are in antenna lines, for High Power, then using proper antenna means that proper filter is coming, too.

PRICE 374 Euros/ single filter

		HF BPF High Power Band pass filters are produced in SKY SAT Communications, Montenegro, owned by Ranko, 4O3A.
4O3A BPF 4O3A filtering system
OH8X OH8X antenna switching with HP BPF		PY5EG PY5EG SO2R filter switching
15M Filter This is the curve of a 15M filter, Model HP BPF TPX, used for triplexer application. Span is from 3MHz to 30MHz and attenuation on 28MHz and 14MHz are 75dB, with insertion loss of 0,35dB.		S51A S51A Switching