Freq range of radio greater than freq range of antenna - any possible problems ?

[mmckenna]

Okay, thanks again, I'll ponder over both since you said either would be okay for 25 feet of run.

I try to allow time to think about different products/brands before eventually ordering as I like to be fairly confident before ordering anything instead of later wishing I ordered something else

Excellent plan. No need to rush. You may be able to find better deals than the one I shared.

 

[GKLdiy88]

Excellent plan. No need to rush. You may be able to find better deals than the one I shared.

Yep, it can be amazing when you start researching products online and you find there are many more brands and selections of products to choose from than you thought sometimes, and it can be a challenge sorting thru them looking for a combination of both a good product and good deal

 

[AK9R]

Regarding DX Engineering, if your order totals $100 or more, they usually waive the shipping fee.

I sometimes find myself on DX Engineering's website ordering something I "need" that's less than $100 only to "pad" my order with other stuff to get my order over $100.

I've ordered pre-made cables from DX Engineering and I have no complaints about the quality of the cable or connectors.

 

[GKLdiy88]

Regarding DX Engineering, if your order totals $100 or more, they usually waive the shipping fee.

I sometimes find myself on DX Engineering's website ordering something I "need" that's less than $100 only to "pad" my order with other stuff to get my order over $100.

I've ordered pre-made cables from DX Engineering and I have no complaints about the quality of the cable or connectors.

Thanks, and I surely agree with your logic, and if the cost of what I wanted to buy was reasonably close to $100 I'd likely pad the order to save on the shipping cost, but the cost of the item I might order is only $40.49 so the "padding" would be more than the cost of what I really need to get (and I've already been pushing the current limits of my modest hobby budget with stuff I've bought in recent weeks )

 

[GKLdiy88]

Thanks, and I surely agree with your logic, and if the cost of what I wanted to buy was reasonably close to $100 I'd likely pad the order to save on the shipping cost, but the cost of the item I might order is only $40.49 so the "padding" would be more than the cost of what I really need to get (and I've already been pushing the current limits of my modest hobby budget with stuff I've bought in recent weeks )

Okay, here's the latest update.

I was originally considering getting the Tram Model #1480-B from Lowe's as I can get the 10% off discount as a veteran.

Tram 6 dBd Gain VHF/8 dBd Gain UHF Black Amateur Dual Band Base Antenna

After considering some of the comments on the forum about Tram antennas (some good but some that make you a little leery) and then checking the DX Engineering web site and seeing a quality antenna for roughly the same price and realizing I could get free shipping with the total order I went ahead and ordered the following:

Comet GP-1 Dual-Band VHF/UHF Base Vertical Antennas GP-1

DX Engineering 400MAX PL-259 Low-Loss 50-ohm Coax Assemblies DXE-400MAXDX025

Permatex Dielectric Grease 22058

and I had already gotten this from Amazon:

3M Scotch Vinyl Electrical Tape Super 88, Premium Grade All-Weather, 3/4 in x 44 ft, 8.5-mil thick

As far as the DX Engineering coax cable I got, being on a tighter than usual hobby budget (after all the Ham stuff I already bought in recent weeks) I had to decide between getting 50 feet of cheaper cable or 25 feet of the recommended high quality cable, so after having read how important good coax is to overall radio performance I opted for the higher quality 25 feet.
(also I wanted the coax to be shorter rather than longer from being in a semi-rural area far from repeaters with a 25watt radio)

.......now as much as I'd like to have the outdoor antenna up sooner than later I do not want to rush but want to be sure exactly how I want to proceed (can't rush anyhow as we have many rain days coming up over the next 10 days).

One thing I have to decide is where to mount the antenna, originally I was thinking of attaching it to a vent pipe near the edge of the roof which is close to where the radio would be indoors but I might need to rethink that for a few different reasons.

After searching online to read other's experiences with mounting antennas I read that some do not recommend attaching an antenna to a PVC vent pipe.

We live in a doublewide manufactured home and the vent pipes do seem to be PVC (I'll have to double check to be sure).

Also the vent pipe is not very tall, here is a photo:


The other issue is being very leery about drilling a hole in the wall for the coax. (my wife never asked about how I would run the cable but I kinda think she might prefer I used some solution other than drilling a hole in the wall ) (not saying it is completely out of the question, could also consider drilling a hole near the corner of the floor, but was hoping I could avoid either)

I read about the idea of using a 2x4 in a window, but the only window is far enough away that if I used that idea it might mean the base of the antenna will be below the edge of the roof line.

There is a sliding glass door about 3 to 4 feet from where the radio is at but can't use the 2x4 idea in a sliding glass door.

I have really really stretched my hobby budget in recent weeks so I need to try to use what I already have, or if something under $20 is still needed for now that might be okay. (hey, I really stretched my hobby budget recently )

I still need to use Chirp to program the radio, but should I program it now using the indoor magnetic mount antenna or wait till later whenever I get the outdoor Comet antenna hooked up or does it matter ?

(Note: don't take any of my comments as complaining, I do enjoy and have fun with what I can afford, even if it is a challenge at times to make do with what I can get )

 

[mmckenna]

Skip the dielectric grease. It won't replace proper sealing of the connector.

Doesn't look like there is enough vent pipe sticking up to mount much of an antenna. I'd get a piece of fence top rail pipe and mount that next to your home. That'll get you about 20 feet up and you won't have to mess with coax running across the roof and attaching an antenna to a plastic pipe.

As for running the cable, bring it in underneath. You can lift up the corner of the carpet, drill down under the floor, and feed your cable in that way. Plug the gap with some sealing putty or silicone.

 

[GKLdiy88]

Skip the dielectric grease. It won't replace proper sealing of the connector.

Doesn't look like there is enough vent pipe sticking up to mount much of an antenna. I'd get a piece of fence top rail pipe and mount that next to your home. That'll get you about 20 feet up and you won't have to mess with coax running across the roof and attaching an antenna to a plastic pipe.

As for running the cable, bring it in underneath. You can lift up the corner of the carpet, drill down under the floor, and feed your cable in that way. Plug the gap with some sealing putty or silicone.

Thanks, I was thinking of using both the grease on the threads and also using the 3M tape in addition to the grease or should I just skip the grease altogether and only use the 3M tape ?

The room has vinyl flooring (no rug) but the corner where I would drill the hole has a large upright freezer in front of it (I would temporarily move the freeze to drill the hole if I choose to do it that way)

The fence rail is a good idea, might not be able to get it immediately as it would be about $50 for the pipe and hardware needed.

I have read opposing opinions on the necessity of grounding the Comet antenna, would grounding be necessary for this type of antenna ?

 

[prcguy]

The Tram dual band you considered is 90" tall and the Comet GP-1 is about 50" tall, despite what the advertising says the Tram will put out a noticeably better signal. I've have a Tram 6dB near Boston for about 5yrs and its doing fine. I have the larger 17ft version near Dallas, TX and its also doing fine, no leaks, works great despite the brutal Texas sun. As mmckenna mentioned, the dielectric grease won't do anything useful. I tested some in the satellite industry filling several dozen connections then checking and testing over about a 5yr period and the treated connectors were no better off than non treated.

With the GP-1 antenna being only 50" tall and very light weight, I would not have a problem attaching it to an ABS vent pipe. ABS pipe that size is very strong and two stainless steel hose clamps around the vent pipe and antenna pipe should be fine. I think the fiberglass antenna housing will snap before the ABS pipe even breaks a sweat.

With the antenna connection being up inside the mounting pipe you don't need to weather proof it like a fully exposed connection. Scotch 33+ is thinner than Super 88 and I think it conforms and sticks better than 88. A couple of layers of 33+ that extend past the connectors should last a lifetime inside the pipe.

When you run the coax through a wall or window mount, etc, bring the coax below the entry point off to the side then back up to the hole, that will make a drip loop and keep water from running down the coax right into the hole area.

Okay, here's the latest update.

I was originally considering getting the Tram Model #1480-B from Lowe's as I can get the 10% off discount as a veteran.

Tram 6 dBd Gain VHF/8 dBd Gain UHF Black Amateur Dual Band Base Antenna

After considering some of the comments on the forum about Tram antennas (some good but some that make you a little leery) and then checking the DX Engineering web site and seeing a quality antenna for roughly the same price and realizing I could get free shipping with the total order I went ahead and ordered the following:

Comet GP-1 Dual-Band VHF/UHF Base Vertical Antennas GP-1

DX Engineering 400MAX PL-259 Low-Loss 50-ohm Coax Assemblies DXE-400MAXDX025

Permatex Dielectric Grease 22058

and I had already gotten this from Amazon:

3M Scotch Vinyl Electrical Tape Super 88, Premium Grade All-Weather, 3/4 in x 44 ft, 8.5-mil thick

As far as the DX Engineering coax cable I got, being on a tighter than usual hobby budget (after all the Ham stuff I already bought in recent weeks) I had to decide between getting 50 feet of cheaper cable or 25 feet of the recommended high quality cable, so after having read how important good coax is to overall radio performance I opted for the higher quality 25 feet.
(also I wanted the coax to be shorter rather than longer from being in a semi-rural area far from repeaters with a 25watt radio)

.......now as much as I'd like to have the outdoor antenna up sooner than later I do not want to rush but want to be sure exactly how I want to proceed (can't rush anyhow as we have many rain days coming up over the next 10 days).

One thing I have to decide is where to mount the antenna, originally I was thinking of attaching it to a vent pipe near the edge of the roof which is close to where the radio would be indoors but I might need to rethink that for a few different reasons.

After searching online to read other's experiences with mounting antennas I read that some do not recommend attaching an antenna to a PVC vent pipe.

We live in a doublewide manufactured home and the vent pipes do seem to be PVC (I'll have to double check to be sure).

Also the vent pipe is not very tall, here is a photo:
View attachment 136112

The other issue is being very leery about drilling a hole in the wall for the coax. (my wife never asked about how I would run the cable but I kinda think she might prefer I used some solution other than drilling a hole in the wall ) (not saying it is completely out of the question, could also consider drilling a hole near the corner of the floor, but was hoping I could avoid either)

I read about the idea of using a 2x4 in a window, but the only window is far enough away that if I used that idea it might mean the base of the antenna will be below the edge of the roof line.

There is a sliding glass door about 3 to 4 feet from where the radio is at but can't use the 2x4 idea in a sliding glass door.

I have really really stretched my hobby budget in recent weeks so I need to try to use what I already have, or if something under $20 is still needed for now that might be okay. (hey, I really stretched my hobby budget recently )

I still need to use Chirp to program the radio, but should I program it now using the indoor magnetic mount antenna or wait till later whenever I get the outdoor Comet antenna hooked up or does it matter ?

(Note: don't take any of my comments as complaining, I do enjoy and have fun with what I can afford, even if it is a challenge at times to make do with what I can get )

 

[GKLdiy88]

The Tram dual band you considered is 90" tall and the Comet GP-1 is about 50" tall, despite what the advertising says the Tram will put out a noticeably better signal. I've have a Tram 6dB near Boston for about 5yrs and its doing fine. I have the larger 17ft version near Dallas, TX and its also doing fine, no leaks, works great despite the brutal Texas sun. As mmckenna mentioned, the dielectric grease won't do anything useful. I tested some in the satellite industry filling several dozen connections then checking and testing over about a 5yr period and the treated connectors were no better off than non treated.

With the GP-1 antenna being only 50" tall and very light weight, I would not have a problem attaching it to an ABS vent pipe. ABS pipe that size is very strong and two stainless steel hose clamps around the vent pipe and antenna pipe should be fine. I think the fiberglass antenna housing will snap before the ABS pipe even breaks a sweat.

With the antenna connection being up inside the mounting pipe you don't need to weather proof it like a fully exposed connection. Scotch 33+ is thinner than Super 88 and I think it conforms and sticks better than 88. A couple of layers of 33+ that extend past the connectors should last a lifetime inside the pipe.

When you run the coax through a wall or window mount, etc, bring the coax below the entry point off to the side then back up to the hole, that will make a drip loop and keep water from running down the coax right into the hole area.

Thanks, you also make some good points, I'll think about the mounting for a while and decide later on (no rush with the rain due starting tomorrow) (I do like that the vent pipe is not too far from the edge of the roof so no long run of cable on the roof itself)

In the meantime would it matter if I programmed my radio via Chirp using the indoor magnetic mount antenna or does the programming take into account what antenna is connected at the time ?

 

[prcguy]

Program away and have fun with the mag mount antenna, Chirp doesn't know anything about antennas.

Thanks, you also make some good points, I'll think about the mounting for a while and decide later on (no rush with the rain due starting tomorrow) (I do like that the vent pipe is not too far from the edge of the roof so no long run of cable on the roof itself)

In the meantime would it matter if I programmed my radio via Chirp using the indoor magnetic mount antenna or does the programming take into account what antenna is connected at the time?

 

[GKLdiy88]

Update: it's been a while since I was up on the roof so I found photos I took of the roof last time I was up there, after getting a better idea where that vent pipe is (can't see it from the ground) I realized it was likely too far away for me to use my 25 feet of coax, so I will opt for using a piece of metal fence rail.

I can fasten the fence rail to the 4x4 porch post that is next to the wall, with it starting at that height I will just need one piece of fence rail to reach about 2 1/2 feet above the edge of the roof, so that will make the base of the antenna about 2 1/2 feet above the edge of the roof with the top of the antenna obviously higher than that by about 4 feet or so.

Even though I would have to wait past some rainy days to start on the antenna project I went by the local hardware store to get the fence pole (theirs is 10 1/2 feet long) and get about 3 hose clamps to fasten it to the 4x4 post and also some zip ties for the cable (to use along with tape).

.....but I'll have to wait till later next week as the clerk said someone came by about 45 minutes earlier and bought the last 2 fence poles they had in stock, also they did not carry hose clamps large enough for what I needed, I was able to get the zip ties though !

Hey, no big deal, I knew I wasn't going to be able to work on it right away anyhow !

Here is a photo showing the porch post I plan on fastening the fence pole to:

 

[GKLdiy88]

Update: the local hardware had gotten more 10 1/2 ft metal fence rails in so I went and got one today to use as the mast to attach the Comet GP-1 antenna to.

The soonest I might have time to put it up is Monday, but I wanted to see how tall it would be so I temporarily set it where it would go and took a picture.

It looks like it should make the antenna high enough.
(should I attach a ground wire to the bottom of that mast pole or does it matter for that height ?)

 

[mmckenna]

You absolutely want to ground the mast. Attaching a ground conductor at the base to a ground rod, and bonding that ground rod to the homes ground rod is a good plan. NEC has something to say about it also:

https://www.mikeholt.com/instructor2/img/product/pdf/17LED-1498-sample.pdf

 

[GKLdiy88]

You absolutely want to ground the mast. Attaching a ground conductor at the base to a ground rod, and bonding that ground rod to the homes ground rod is a good plan. NEC has something to say about it also:

https://www.mikeholt.com/instructor2/img/product/pdf/17LED-1498-sample.pdf

Thanks for that info, I can put a ground rod in below where the bottom of the mast will be.

But it would be difficult to bond that to the home's ground rod as the home's ground rod is on the opposite side of the house where the electric meter is and that ground wire disappears into the ground so that ground rod must be underground.

Hopefully not having the mast ground rod connected to the ground on the other side of the house will not be a real concern. (we live in a double-wide manufactured home)

 

[mmckenna]

Hopefully not having the mast ground rod connected to the ground on the other side of the house will not be a real concern. (we live in a double-wide manufactured home)

Actually, it is a concern.

What you might end up with is a difference in ground potential. That can be dangerous, not only for lightning, but also electrical faults in your home. Having the radio connected to an antenna with its own non-bonded ground rod, and the power supply ( and any other electrical appliances) connected to a different (and questionable) ground rod, is dangerous.

Carefully excavating around the original ground rod would be a good idea to see if it is still good. If it's been buried and not checked since installation, that can be a bad thing.

When it doubt, call and licensed electrician. It's a safety thing, and we don't want to hear about a fried up GKLdiy88 on the news.

 

[GKLdiy88]

Actually, it is a concern.

What you might end up with is a difference in ground potential. That can be dangerous, not only for lightning, but also electrical faults in your home. Having the radio connected to an antenna with its own non-bonded ground rod, and the power supply ( and any other electrical appliances) connected to a different (and questionable) ground rod, is dangerous.

Carefully excavating around the original ground rod would be a good idea to see if it is still good. If it's been buried and not checked since installation, that can be a bad thing.

When it doubt, call and licensed electrician. It's a safety thing, and we don't want to hear about a fried up GKLdiy88 on the news.

Okay, I definitely appreciate the alert and concern, I might need to put off the antenna install until I am ready to do it right, I'll need to locate the home ground rod underground and also need to get as much as 50 to 60 feet of copper wire to reach that far from the antenna mast out back.

 

[PrivatelyJeff]

Actually, it is a concern.

What you might end up with is a difference in ground potential. That can be dangerous, not only for lightning, but also electrical faults in your home. Having the radio connected to an antenna with its own non-bonded ground rod, and the power supply ( and any other electrical appliances) connected to a different (and questionable) ground rod, is dangerous.

Carefully excavating around the original ground rod would be a good idea to see if it is still good. If it's been buried and not checked since installation, that can be a bad thing.

When it doubt, call and licensed electrician. It's a safety thing, and we don't want to hear about a fried up GKLdiy88 on the news.

Not to hijack but what would you do in a case where the electrical ground is the foundation of the house? My place is a tract home that’s about 30 years old and there’s no exposed ground by the panel. The cable company (Comcast) just grounded to the panel with a clamp type device.

 

[mmckenna]

Not to hijack but what would you do in a case where the electrical ground is the foundation of the house? My place is a tract home that’s about 30 years old and there’s no exposed ground by the panel. The cable company (Comcast) just grounded to the panel with a clamp type device.

If it's like my house (built on a slab) it uses rebar as the ground. I've got a stub of rebar sticking up out of the foundation in the garage under the main entrance panel. That's the house ground.
I'd look around your main panel, might be behind sheetrock.

 

[GKLdiy88]

Not to hijack but what would you do in a case where the electrical ground is the foundation of the house? My place is a tract home that’s about 30 years old and there’s no exposed ground by the panel. The cable company (Comcast) just grounded to the panel with a clamp type device.

No problem, I'm glad to hear related problems and the ideas offered, always helps to learn from others !

 

[PrivatelyJeff]

If it's like my house (built on a slab) it uses rebar as the ground. I've got a stub of rebar sticking up out of the foundation in the garage under the main entrance panel. That's the house ground.
I'd look around your main panel, might be behind sheetrock.

That sounds familiar. I’ll have to look.