DQOTD: Coax Cable Connectors!!!

[Midpack]

I need connectors for a VHF antenna, so I can separate an RG-8X cable as needed. Every merchant I talk to tells me I need to buy PL-259 connectors with RG-8X adapters, and solder the tips (at a minimum).

Like everyone, I've had CATV/Satellite/data cables in use for decades, at my home they're mostly RG-6U, with simple screw/press/crimp on F connectors and a bare center wire. Techs install them in seconds. They seem to work just fine.

I realize there are differences in the ohms, losses, center conductor, dielectric, shielding etc. between RG-6U vs RG-8X but they are not wildly different OD's. In fact the RG-8X is slightly smaller OD than RG-6U

So why do I need to use big, honkin PL-259's for RG-8X, they are HUGE by comparison to F connectors. I couldn't find a side by side (scale) picture, but I did find a PL-259>F adapter, which shows the relative diameter/size (your CATV and internet cable connectors would fit on the small end of these adapters, to give you an idea of the relative size of a PL-259).

Is there a smaller connector I can use for an RG-8X connection, or is there some good reason I need to use big, honkin' PL-259's? I sure hate to drill that great big hole to pass a PL-259 through if there's a smaller connector that will work just as well.

Obviously sparky stuff is not my forte, I know there are some strong electrical types here. TIA.

 

[M Paquette]

Most RG8X cable uses a stranded center wire, which generally needs to be soldered or crimped to a rigid center pin. The RG6 stuff (Cable TV, etc) has a single thicker center wire, often copper clad steel, which is rigid enough to be used as the center pin in the Type F connectors.

I have some antennas I've set up with RG6 cable all the way into the house, and I use an adapter similar to the one pictured, only female RG6 to the male PL259 end, to connect the cables to radio equipment. Like the thin foam dielectric RG8X cable, RG6 has a lower breakdown voltage than the big RG8/LM400 sorts of cable, so one has to use care if using it for transmitting.

 

[easysurfer]

Sorry I can't help about the connections. But the post gave me a chuckle as immediately I imagined Fallon and Higgins with their Monster Cable bit

 

[NW-Bound]

RG-8X has a characteristic impedance of 50 Ohms, and the RG-6/U is 75 Ohms. The latter matches the impedance of TV equipment better, although a bit of mismatch (causing additional loss) may not be observable.

Regarding the connector size, I think RG-8X and its connectors are meant for semi-portable or removable uses, hence the finger-friendly size, while RG-6/U is meant for fixed installations. It's also why RG-8X is stranded center wire for flexibility, while RG-6/U is solid center conductor.

RG-6/U has lower attenuation, and most likely cheaper. So, why do you use the other?

 

[Midpack]

Sorry I can't help about the connections. But the post gave me a chuckle as immediately I imagined Fallon and Higgins with their Monster Cable bit

DEE VEE DEE !!!

 

[Midpack]

Most RG8X cable uses a stranded center wire, which generally needs to be soldered or crimped to a rigid center pin. The RG6 stuff (Cable TV, etc) has a single thicker center wire, often copper clad steel, which is rigid enough to be used as the center pin in the Type F connectors.

I have some antennas I've set up with RG6 cable all the way into the house, and I use an adapter similar to the one pictured, only female RG6 to the male PL259 end, to connect the cables to radio equipment. Like the thin foam dielectric RG8X cable, RG6 has a lower breakdown voltage than the big RG8/LM400 sorts of cable, so one has to use care if using it for transmitting.

RG-8X has a characteristic impedance of 50 Ohms, and the RG-6/U is 75 Ohms. The latter matches the impedance of TV equipment better, although a bit of mismatch (causing additional loss) may not be observable.

Regarding the connector size, I think RG-8X and its connectors are meant for semi-portable or removable uses, hence the finger-friendly size, while RG-6/U is meant for fixed installations. It's also why RG-8X is stranded center wire for flexibility, while RG-6/U is solid center conductor.

RG-6/U has lower attenuation, and most likely cheaper. So, why do you use the other?

The RG-8X was already strung by the previous owner, it would be a lot of work to replace. And the VHF antenna works with RG-8X, I just need to add suitable connectors, and was wondering if I could avoid (the size of) PL-259's.

 

[easysurfer]

DEE VEE DEE !!!

 

[ls99]

Just tin (solder) the center Conductor, make sure no excess solder, then fit the F connector. Fold back the shield over the insulation it will be a nice tight fit.

For uses where it is rarely disconnected it will be fine. I've done it and it works, a lot cheaper too.

 

[bingybear]

I just took a look online... not used RG-8X for anything...

with a quick look online... (no I did not look for best price) but 50 ohm F connector for RG-8X.

Note you can't use the cheap assembly tools the cable guys do... -- not that the soldering technique is expensive.

BTW.. if the cables are just strung through the walls with no mountings (things like stapled to joists)... you may be able to pull other through while pulling that out.

 

[braumeister]

If you don't want big connectors, why not use BNC?

 

[NW-Bound]

Just tin (solder) the center Conductor, make sure no excess solder, then fit the F connector. Fold back the shield over the insulation it will be a nice tight fit.

For uses where it is rarely disconnected it will be fine. I've done it and it works, a lot cheaper too.

+1

For this application, a jury rigged connection is not going to hurt anything. The frequency is relatively low, so bitty extra loss is not at all noticeable, and it is not a power-handling application such as for a transmitting antenna.

 

[bingybear]

+1

For this application, a jury rigged connection is not going to hurt anything. The frequency is relatively low, so bitty extra loss is not at all noticeable, and it is not a power-handling application such as for a transmitting antenna.

If you use an F connector designed for RG-8X (link in my earlier post)... this would not be jerry rigged. I believe these were soldered on pin with crimped shield. One could try to rig on the wrong connector... but why in this case?

 

[Midpack]

Just tin (solder) the center Conductor, make sure no excess solder, then fit the F connector. Fold back the shield over the insulation it will be a nice tight fit.

For uses where it is rarely disconnected it will be fine. I've done it and it works, a lot cheaper too.

+1

For this application, a jury rigged connection is not going to hurt anything. The frequency is relatively low, so bitty extra loss is not at all noticeable, and it is not a power-handling application such as for a transmitting antenna.

I think I will try this. Fortunately there's enough cable slack that if it doesn't work, I can cut them off and put the "Monster" PL-259's on. Thanks!

 

[bingybear]

I think I will try this. Fortunately there's enough cable slack that if it doesn't work, I can cut themT off and put the "Monster" PL-259's on. Thanks!

just buy the F connector made for the RG-8X cable. There's likely no reason to use the large connector PL259.

Likely the best question... what are you connecting this cable to?... what connector type?

 

[NW-Bound]

If you use an F connector designed for RG-8X (link in my earlier post)... this would not be jerry rigged. I believe these were soldered on pin with crimped shield. One could try to rig on the wrong connector... but why in this case?

Well, your proper connector costs $17, and has to be ordered.

On the other hand, if I can shoehorn a cheapo common F connector that I have on hand, well, the quick-n-dirty method wins.

 

[Midpack]

just buy the F connector made for the RG-8X cable. There's likely no reason to use the large connector PL259.

Likely the best question... what are you connecting this cable to?... what connector type?

i have a cut RG-8X cable, no connectors.

Well, your proper connector costs $17, and has to be ordered.

On the other hand, if I can shoehorn a cheapo common F connector that I have on hand, well, the quick-n-dirty method wins.

I have a buddy with a coax crimper, so I plan to buy cheapo F connectors and tin the center strands.

Still don't understand why the electric supply shops all steered me to PL-259's, whatever.

 

[bingybear]

i have a cut RG-8X cable, no connectors.

I have a buddy with a coax crimper, so I plan to buy cheapo F connectors and tin the center strands.

I'm lost. you have cut cable with no connectors on it. got that.

So I assume you are going to put connectors on the cable, correct?

So when you have put connectors on the cable, what are you going to attach the cable with the newly installed connectors? This was my question.

 

[bingybear]

i have a cut RG-8X cable, no connectors.

I have a buddy with a coax crimper, so I plan to buy cheapo F connectors and tin the center strands.

Still don't understand why the electric supply shops all steered me to PL-259's, whatever.

If by "electric supply places" you mean ham radio shops, this is a very standard connector used in their equipment.

 

[Midpack]

I'm lost. you have cut cable with no connectors on it. got that.

So I assume you are going to put connectors on the cable, correct?

So when you have put connectors on the cable, what are you going to attach the cable with the newly installed connectors? This was my question.

As stated in the OP, the cable runs to a VHF antenna with a cheapo manufacturers proprietary connector. And of course a VHF radio on the other end with a PL-259.

 

[bingybear]

As stated in the OP, the cable runs to a VHF antenna with a proprietary connector. And of course a VHF radio on the other end with a PL-259.

then I would use the PL259 on at least the radio end. The other end would depend of what the other connector will mate to. that is assuming this cable goes between the radio and the antenna.

I thought you wanted to stay away from the adapters. I would think a PL-259 (radio) connecting to a PL-259 (cable) would be desired. Or are these other additional cables you are using in addition?

Do you know what the connector is at the antenna? I have seen few proprietary connectors in these locations as you need a mating one on the cable. It may just be a less publicly recognized one.

 

[Midpack]

then I would use the PL259 on at least the radio end. The other end would depend of what the other connector will mate to. that is assuming this cable goes between the radio and the antenna.

I thought you wanted to stay away from the adapters. I would think a PL-259 (radio) connecting to a PL-259 (cable) would be desired. Or are these other additional cables you are using in addition?

Do you know what the connector is at the antenna? I have seen few proprietary connectors in these locations as you need a mating one on the cable. It may just be a less publicly recognized one.

Long way around, but I need a pair of connectors in between, two cables if you will. The approx 50' cable has a PL-259 on the radio end and a proprietary connector on the antenna end AND the cable is (necessarily) cut in two between. I am looking for a pair of the smallest, easiest to install connectors to bridge the break in the middle of the cable...I am going to try crimp on F connectors.

 

[bingybear]

Long way around, but I need a pair of connectors in between, two cables if you will. The approx 50' cable has a PL-259 on the radio end and a proprietary connector on the antenna end AND the cable is (necessarily) cut in two between. I am looking for a pair of the smallest, easiest to install connectors to bridge the break in the middle of the cable...I am going to try crimp on F connectors.

if that does not work... try either an SMA or mini UHF. you can get these for RG-8X for reasonable prices... mini-UHF is likely cheaper than the SMA.

Another you may want to look at would be FME connectors for the same coax.

what is the output power (if any ) for your radio? If high power, may want to consider that. But likely not an issue.

 

[Midpack]

if that does not work... try either an SMA or mini UHF. you can get these for RG-8X for reasonable prices... mini-UHF is likely cheaper than the SMA.

Another you may want to look at would be FME connectors for the same coax.

what is the output power (if any ) for your radio? If high power, may want to consider that. But likely not an issue.

25W high, 1W low transmission power.

 

[NW-Bound]

I misread the OP, and thought it was about using an existing RG-8X cable (50 Ohm) for a TV application which is 75-ohm.

I now see that it is for a VHF radio, which of course works with a 50-ohm coax, and not the 75-ohm cable.

An intermittent connection may not be good for a transmitter, as the latter needs to see a constant load. So, whatever you do, make sure you have a good connection. And jury rigging may not be advisable anymore.