Need fiber distribution

[AntAltMike]

I installed the HDTV headend in a twin tower highrise in metropolitan Washington DC (Arlington, VA, actually) that has 550 units. The antenna array is on the East tower, the MATV trunkline runs from there down through eighteen floors, into the underground parking garage, 500 feet across to the bottom of the almost-twin, seventeen story West tower, and terminates in the seventeenth floor cable closet.

I recently noticed that I can get a clear shot at the Baltimore TV stations from the West tower, but if I moved the whole headend to the West tower, I'd also have to reverse the taps in 70 cable closets and relocate eight distribution amplifiers, so I most likely will send the signal from a new, West tower antenna to the east roof headend, which means the signal will travel down 200 feet, across 500 feet and up 200 feet. Since there is already an unused 500' RG-6 jumper between the two towers, I'll probably use that, but for the top to bottom lengths I'll use RG-11.

There will be a UHF channel 51 in the system even after the transition, so it will be incurring 700Mhz losses through 400' of RG-11 and 500' of RG-6. I will therefore probably have to boost the west tower UHF signal twice to sustain it before it hits my headend, and then it gets amplified two or even three more times in the distribution system.

I am a little concerned about the intermodulation distortion that might come from amplifying broadcast 8VSB signals five times, especially since, even with the signal level balancing that I do, there will be maybe fifteen dB difference between the strength of the strongest and weakest signals.

What would it take to relay the West tower signal to the East tower through 900 feet of fiber? What are the least expensive converters, and what would a 1000 foot roll of pre-connector-ized fiber cost me?

 

[cybertrip]

You would need a single mode fiber node. This is not going to be cheap. You may want to call Scientific Atlantic and see what kind of options they can provide. You will need a RF fiber modulator from your headend then to be converted at a fiber node before your trunk amp. Just more money. Btw, there is no existing fiber between the West and East tower? Using what is already existing would be your cheapest route.

 

[AntAltMike]

...You may want to call Scientific Atlantic and see what kind of options they can provide...

I was hoping for a brand name like Tru Spec, Qintar or Regal. That's my price range.

 

[AntAltMike]

I just got price quotes of $2,200 for a transmitter, $325 for a receiver and $150 for the 900 foot connectorized fiber. from the distributor who usually has the lowest prices.

Realistically, I can't consider it at that price because when I add in the labor of running the fiber plus the responsibility I'd be incurring having to stand behind critical components that I am not outfitted or experienced to service, I'd have to charge the customer maybe $6,000 to $7,000 to do it this way. If I perceive that the problem is the fiber, for example, I'd just have to rerun a new one (half a day's labor) because I have no optical TDR to locate a defect, and no expertise at splicing fiber.

The transmitter specs are:
54Mhz-860 CATV only,
40 ch
1310NM
3dB

The quote did not name the manufacturer

I don't know the nature of the inputs. I don't see what would limit it to 40 channels. Might it actually have 40 "F" connector inputs for 40, 6Mhz ATSC channels?

If that is the case, the "cable only" term concerns me, because it might have a dedicated channel plan that will not match up with my UHF signals. There were a lot of CATV demodulators that could not select the UHF, 750Mhz channel plan frequencies.