Can I have the best of both worlds, F-Type connection and wireless?

[obsolete man]

Hey Guys, so in my home... against a display shelf/wall. I have many vintage tvs. I've managed to wire many of them to a bunch of bonder tongue mini agile modulators.

So here's my set-up..

1. Six agile modulators all go into a combiner.
2. The combiner then outputs to a 10-way splitter.
3. From here, we f-type coaxial directly to various tvs. These tvs receive perfect reception. This allows me to change to six channels all with different shows.
4. One of the output on this splitter is connected to an antenna for tvs that cannot get a direct connection.

I realize with this set-up the antenna as a transmitter is TERRIBLE. I found out that for the antenna to work its best as a transmitter, it needs to be connected to the agile modulator directly. But then there would only be one source airing wirelessly. I also connected the antenna to the output of the combiner to see if that would improve, and if it did, then I would remove the splitter and just have all tvs go wireless. However, even when putting antenna at the combiner, it was no good. Nothing I did compared to connecting the antenna directly to a modulator.

Is this limitation a fact of life for this hobby, or is it because I'm a newbie and don't know of better methods? If there is a way for me to get the best of both worlds. Please school me. Thank you for your time.

[old_tv_nut]

Some one who has done this will chime in with a better answer, I'm sure, but I have a few questions that may help think aobut this:

1) Is the combiner lossless as used?
3) what channels are you using?
3) for wireless, what kind of receiving antennas are you using?

[obsolete man]

Originally Posted by old_tv_nut

Some one who has done this will chime in with a better answer, I'm sure, but I have a few questions that may help think aobut this:

1) Is the combiner lossless as used?
3) what channels are you using?
3) for wireless, what kind of receiving antennas are you using?

1. Drake PC1601 Passive Combiner. I'm not sure if that means lossless?
2. The usual VHF 2,3,4,5,7,9,11,13
3. For transmitting, it's a cheap RCA has two dipoles and the middle is a round UHF. For receiving, it's whatever built in antenna the tv has.

[old_tv_nut]

My first guess is you would get better results with UHF and dedicated UHF antennas for transmitting and receiving, but I suppose you have some VHF only receivers. In that case, I would expect the upper VHF channels to work better. Are you seeing differences due to channel number? Have you tried adjusting the length of the dipoles?

There have been discussions here on what kind of antenna to use to transmit - give it a search.

Combiner manual says 17 dB insertion loss, so you need a 17 dB amplifier following it to get back to the modulator output level. It also needs to be able to handle the desired signal level without crossmodulation, so you need a 20 dB gain distribution amp designed for the high signal level input; a 20 dB antenna distribution preamp may have problems.

Manual:
https://cdn-docs.av-iq.com/other/PC1601_Datasheet.pdf

[obsolete man]

Originally Posted by old_tv_nut

My first guess is you would get better results with UHF and dedicated UHF antennas for transmitting and receiving, but I suppose you have some VHF only receivers. In that case, I would expect the upper VHF channels to work better. Are you seeing differences due to channel number? Have you tried adjusting the length of the dipoles?

There have been discussions here on what kind of antenna to use to transmit - give it a search.

Combiner manual says 17 dB insertion loss, so you need a 17 dB amplifier following it to get back to the modulator output level. It also needs to be able to handle the desired signal level without crossmodulation, so you need a 20 dB gain distribution amp designed for the high signal level input; a 20 dB antenna distribution preamp may have problems.

Manual:
https://cdn-docs.av-iq.com/other/PC1601_Datasheet.pdf

I found a boost from a leaf antenna that I'm not using. From the combiner, I output to this boost, then this boost goes into the splitter. The antenna that's attached to this splitter works better now. However, I get these ghost bars going from left to right. If it only happens on the wireless sets, that would be okay, but now all the tvs with the direct connection are getting this left to right scrolling bars too.

But I went back to my original set-up without the boost, and I started modulating to some UHF channels, and the wireless reception did work better for some of these UHF channels. But still, not the same quality as direct connect. BTW, when I'm doing these testings, the antenna and the wireless sets are in the same room, maybe just a foot away, and I still can't achieve a clear picture like I would with a direct connect.

[old_tv_nut]

Originally Posted by obsolete man

I found a boost from a leaf antenna that I'm not using. From the combiner, I output to this boost, then this boost goes into the splitter. The antenna that's attached to this splitter works better now. However, I get these ghost bars going from left to right. ...

This is cross-modulation, what you would expect from using an ampifier meant for weak antenna signal levels to amplify a group of higher level signals. You need a cable-system amplifier designed to work at high levels.

[luRaichu]

Originally Posted by old_tv_nut

You need a cable-system amplifier designed to work at high levels.

Aren't we dealing with broadcast frequencies here

[old_tv_nut]

Originally Posted by luRaichu

Aren't we dealing with broadcast frequencies here

Cable frequencies include broadcast frequencies.

[obsolete man]

Originally Posted by old_tv_nut

This is cross-modulation, what you would expect from using an ampifier meant for weak antenna signal levels to amplify a group of higher level signals. You need a cable-system amplifier designed to work at high levels.

What would be more ideal, putting an amp before the combiner or after? If before, then I would need to find an amp combiner? Is there such a thing? LOL!

What are cable system amps? Like any old school blonder tongue amplifier? I searched ebay for Blonder Tongue Amps and most are just one in, one out. Can you tell me which of these search results fits my need?

https://www.ebay.com/sch/i.html?_fro...ifier&_sacat=0

[obsolete man]

Originally Posted by old_tv_nut

This is cross-modulation, what you would expect from using an ampifier meant for weak antenna signal levels to amplify a group of higher level signals. You need a cable-system amplifier designed to work at high levels.

Good news! I just realized something... since my wired pictures are fine, I did not need to put the boost between splitter and combiner, which was causing this cross-modulation even with the wired picture.

I just tried placing the boost between the antenna and one of the outputs on the splitter. But doing this, the boost needed to be used backwards by using a f-type coupler. Wireless reception is much better now with some ghost bars, depending on channel, it can go up and down or left and right, but the picture is clear. And this time, the wired tvs are not effected, they are still crystal clear.

I'm still going to buy some of those blonder tongue amps, just to see how all this looks with better equipment.

[old_tv_nut]

Let me repeat, I'm starting at ground zero of knowing the best way to do this, hope someone else chimes in.

[luRaichu]

By "boost" I think you mean one of those cheap antenna amps designed for RX setups? Wouldn't trust those but I don't know anything that would work better with that kind of bandwidth in mind & for a reasonable price.
I've never heard of anyone airing 6 channels at once for a home setup. Maybe, you will need 6 RF amps before the combiner stage?

[old_tv_nut]

The BLONDER TONGUE BIDA BROADBAND DISTRIBUTION AMPLIFIER 750-30
manual says it's designed for cable-drop input, sounds like the right input level to me, although it doesn't say what signal level exactly.

https://www.manua.ls/blonder-tongue/bida-750-30/manual

The BIDA 550-50 would privide a stronger output, IF it doesn't overload. I would be tempted to try this one first and hope that if it overloads it can be adjusted out with the attenuator, or even by adding an external attenuator if necessary.

[obsolete man]

Originally Posted by old_tv_nut

The BLONDER TONGUE BIDA BROADBAND DISTRIBUTION AMPLIFIER 750-30
manual says it's designed for cable-drop input, sounds like the right input level to me, although it doesn't say what signal level exactly.

https://www.manua.ls/blonder-tongue/bida-750-30/manual

The BIDA 550-50 would privide a stronger output, IF it doesn't overload. I would be tempted to try this one first and hope that if it overloads it can be adjusted out with the attenuator, or even by adding an external attenuator if necessary.

https://www.amazon.com/Reliable-Cabl...ct_top?ie=UTF8

What do you think of something like this? Would it serve the same purpose? It seems to streamline the splitter function with the amp function all in one.

[old_tv_nut]

Originally Posted by obsolete man

https://www.amazon.com/Reliable-Cabl...ct_top?ie=UTF8

What do you think of something like this? Would it serve the same purpose? It seems to streamline the splitter function with the amp function all in one.

No, that's an antenna amplifier intended to handle low level signals, not the high level you are trying to achieve. Also, it's working in the wrong direction, splitting signals instead of combining them.