Hey,

Today, with the help of DHC's Yammon, we went and installed a CM 4228 Antenna at my residence, for my Samsung SIR T-151 reciever. One issue which has arrose, which I would like to get resolved but it is not immediate, is that I am having some frequency issues. Presently, attached to the house is a DirecTV Phase III Satellite dish, which is not presently being used except for the Free Music Stations provided from DirecTV. The 4 lines that run from the Phase3 are inserted into a TERK BMS 5-8 multiswitch, with 7 lines running throughout the house. The concept that I came up with, and we installed too, was that to just add the CM 4228 feed into the Antenna Input of the BMS 5-8, so it would distribute throughout the house (with the power being inserted by the CM 7775 Titan2 UHF Preamplifier inserted prior to the signal coming into the multiswitch (as for whatever reason, the Power was not passing through the antenna input). With a line connected directly to any satellite reciever, all Transponders are fine. When the antenna is plugged directly into the BMS 5-8 all stations come in as well (depending on how far away from the BMS 5-8, some stations have some signal loss), This is, when unfortuantly, Yammon had to leave (as I had an appoitnment I was late for). This is when the issue arrose, as when I use a diplexer, so that both the satellite and SIR-T151 reciever everything begins to act funny, as I lose some stations (SunTV, WIVB/CBS and WNED/PBS). Additionally, only some of the even transponders appear to have signal, as the odd transponders kick out.

I was using the Eagle Aspen D-2000LX Diplexer, as I know it had worked in the past (was previously using it to combine satellite and cable signal and then split it again on the other side of the room so there was only one cable being ran), and I figured the reason it was not working was because the Eagle Aspen dipelxers use a frequency range of 950/2050 MHZ and 5-860 MHZ where as the Terk BMS 5-8 is using a frequency range of 950- 2150 MHz, 54- 806 MHz . So I ran over to The Source, by Circuit City and grabbed a Nextech 2x1 5-2450 MHZ Splitter. I figured this would do the trick, as it is lower than the 54 MHZ and higher than the 2150MHZ. However, same issue, channels dropped out and I lost some transponders.

So now I am confused and not so sure what I should do. How can I get a signal for both the satellite and the antenna to work? Is it possible (and it is a hypothesis I have), that ATSC signals are at a higher frequncy than the designed 5-900 MHZ frequency used for NTSC, and therefore the two signals are interfering with each other? Perhaps I am required to get a Terk BMS 21, but I would rather not have to special order a dipexer to fit that range...

Anyone with any knowledge or ideas would be of great use...

Thank you,

alebowgm

The TV antenna signals, channels 2 - 69, are in the 54 - 860 MHz range, and the dish signals are usually in the range of 950 -1650 (I think) MHZ. The ability of one device to respond to frequencies outside of these ranges should not affect your system at all, so it looks like your setup should be okay with the original parts.

It is to be expected that the antenna input of the multiswitch does not pass DC. DC at specific voltages is required from the satellite receivers up to the dish, so if the antenna signal is mixed with those signals, it can't mix any DC. That's why the preamp's power supply has to go upstream from the multiswitch.

Check the signal coming out of the multiswitch to see if both halves of it are okay by NOT using a diplexer and:
a) connecting it to the satellite input, checking for all transponders, then
b) connecting to the UHF/VHF input and checking for digital TV stations.

If all is well with that cable when connected independently to each half, then the problem is in the diplexer.

The BMS 5-8 has its own power supply, right?

By the way, I have seen lots of such problems and this is a new one on me, so I am trying to gather more information.