Which is it, RG59 or RG6?

Well, the leak or ingress goes both ways. While ingress from ham, commercial, and broadcast radio xmitters are irritating, the regulatory requirement is to prevent cable leakage from interfering with public safety, aircraft, and of course, OTA broadcast. Lots of nice toys to measure this leakage:

Ummm... the OP is trying to troubleshoot his home installation, not the trunk line (or cable drop). I think it's a safe bet that he can unplug his spaghetti without difficulties.

The idiot manager of one system ordered the wrong midband modulator that was right in the aircraft band. Rather than admit it, over 10,000 converters had to be modified to tune the new channel. It was used to add 'The nashville Network' which had just been launched. The system was in the Cincinnati area where people claimed that they didn't listen to 's*it kicking music'. I tested the mew modulator & c-band equipment for less than 30 seconds, and after 2 am. We had over 100 phone calls waiting the next morning, wanting to know when it would be back.

Then it is very unlikely he will have access to a TDR, sniffer or any other equipment. Even a field strength meter isn't likely.

the tap plates were cast aluminum if they were Jerrold, or plated brass threads bolted to an aluminum plate in Lindsay taps. Both cause problems in areas where road salt was used. Just as bad were the unplated brass cable connectors someone tried to sell us.

Run the tests again after a 48 hour salt spray test.

Again, this is for outdoor use. The OP is doing indoor.

Actually, I have. I used to design marine radios and the salt fog test was one of the hazards of the business. None of the equipment survived 100%. We were just checking for problems that might occur in a marine atmosphere. As I recall, the silver plated brass connectors did quite well, while the cadmium plated pot metal died a horrible death. Dissimilar metals and connector materials were also bad. Unless you watch TV in the shower, I don't think any of these will be a problem with an indoor installation.

So is there any value in getting gold-plated F connectors (if they have them) or gold-plated A/B switches (which I know they sell)?

It's the A/B switch I'm particularly curious about because at one store, that was all they had, and some antenna signals are so weak, I figured any little thing might help.

Or other gold plated connectors?

No. The plating is so thin, that at UHF frequencies, the skin depth is less than the plating depth. If you want good RF conductivity, get silver plated connectors. The real problem with gold is dissimilar metals. Although gold will not corrode, oxidize, or rot, it will create an electrolytic junction when wet. The result is some noise, and possibly some corrosion of the other junction metal. What that means is that gold is a fair idea if you use all gold connectors, everywhere. It's not so great an idea if you mix materials.

However, that's really only for exterior installations, where water can get into the connectors and devices. For indoor use, it's not so much an issue unless you live in the tropics, on a boat, or in a swamp.

Ok, so we're off cable TV and onto OTA (over the air) issues.

The biggest improvements you do for signal strength are (in order of importance):

1. Location, location, location, location, line of sight, etc.
2. Selection, design and construction of the antenna(s).
3. A tower mounted amplifier.
4. Everything else. If you've done the first 3 items, to the best your abilities and finances, then tinkering with plating materials and A-B switches is a waste of time and money.

I've been told it's a swamp, but I disagreed.

Good to know. Thanks.

Ouch. However, the aircraft band is from 108 to 136Mhz. That covers channels 98, 99, 14, 15, and 16 that have to be protected. Comcast is using 14 and 15 locally, but I've noticed that the signal levels are much lower than the adjacent channels.

Chuckle. There's no accounting for taste. For the last year or so, I've been erratically trying to convince DirecTV to carry UCTV:

It's currently carried by Dish and Comcast locally, but not DirecTV. So far, my efforts have been futile. So, I watch UCTV on the computah.

If he can borrow an oscilloscope, a TDR is very easy to build. I've built several similar to:

If he knew the test frequency, a simple scanner with aircraft band should work. Every cable operator seems to use a different frequency. I usually find it by connecting my scanner to the cable, and scanning the aircraft band for the obnoxious tones.

The system added TNN at my insistence. We picked up about 500 new customers by adding it. The number one country music station in the US was in Cincinnati for several years.

I preferred my homebrew return loss bridge. I used a surplus video modulator module for the Atari 2600, and built the bridge in a Pomona diecast box. It was a lot more useful than a TDR in troubleshooting the MATV systems in dozens of schools.

United Video always used the video carrier frequency of the first channel past what the system used.

In message , Michael A. Terrell writes

No it doesn't. It means that the isolation - the loss between two outputs (with the input terminated) - is 20dB.

True - but, more generally, it is to minimise the effects of something connected to one output affecting another output. As well as protecting against local oscillators, it also protects against incorrect loading (ie if an output port is not correctly terminated in a 75 ohm load). It should not matter (too much) if an output is left open circuit, short circuited, has a length of cable connected to it but going nowhere, etc etc.

Was your statement above (about RLR) one of these? [Sorry. The Devil made me say that! ;o))]

While most 3-ways are typically 3.5/7/7, there are one or two around with equal outputs, of appx 5.5dB (although, personally, I can't really see much need for them).

Sigh. How do you think you measure that isolation?

What are you connecting that doesn't have a TV tuner? FM radios are supposed to use a single port -20 dB tap.

Unterminated ports are not allowed in properly designed systems. PERIOD.

You would, if the use of the 3.5/7/7 would require a second drop from the line tap on the street.

In message , Michael A. Terrell writes

Sigh as much as you like - isolation and RLR are definitely NOT the same thing, and you don't measure them in the same way.

That could make the FM level uncomfortably low. It's better to separate the FM from the TV signals via a bandpass diplexer filter. This is/was common practice in Europe. Of course, in the USA, you have always had your Channel 5 (running right up to the LF end of the FM band). Also, these days, you could have digital TV signals starting immediately above the FM (and still meeting the 'no interference' regulations for Air Traffic Control radio. Do any cable systems still actually carry FM radio?

They may be installed correctly terminated, but you can bet your bottom dollar a lot won't stay that way!

When I said "much use", I meant "MUCH use". While a computerized CATV system planner may flag up an out-of-spec condition, in practice, there may be less than 1dB difference between a nominal 5.5 and 7dB.

You use the same equipment, but connect the ports in a different order.

A 0 dB or higer signal will overload the front end of a FM radio. O dBM is 1000 microvolts @ 75 Ohms. FM radios are supposed to work at full quieting 10 microvolts. Some of the -20 dB taps were labeled as FM Taps and were supposed to have a bandpass filter on the output port but none of the ones I tested in the lab did.

No, it is Channel 6, with the aural carrier at 87.7 MHz. That is .3 Mhz below the bottom edge of the 88 to 108 MHz FM Broadcast band.

Are you kidding? They were dropped as soon as the franchises stopped asking for FM and wanted more video channels. They gained three midband channels without rebuilding the system.

Not if it's maintained by morons. But then, those systems were never in spec.

So? If the franchise calls for all drops to be above 0 dB, one dB is out of spec.

On Dec 9, 3:46=A0pm, "Michael A. Terrell" wrote: ...snip...

...snip...

being a bit pedantic,

I meant 0 dBmv, which is used in TV Land.

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Understood. Thanks.

I forgot to add the 'v' after 20+ years out of TV broadcasting, then spending years building Telemetry gear. :(

But given that the center pin on an F connector is the bare copper center conductor of the cable, I don't think I'd bother. If we were talking BNCs or something plating might make sense.