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Homebase Setup


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Considering options for a homebase antenna setup. My mag mount lets me hear loud and clear those on the nearest repeater, however, my transmission is staticky and low. Here are a couple items on my wishlist...any comments, advise, recommendations are appreciated...


1) RG58 Coaxial Cable 49.2FT UHF PL-259 Male to Male Low Loss Cable for Ham Radio CB Antenna Cable Radio WiFi Extension Coax for VHF HF 50 Ohm rg 58 Coax 


2) TWAYRDIO Foldable Ham Radio Yagi Antenna UHF 400-470Mhz Long Range 7dBi Signal Booster GMRS Directional Yagi for Repeater System,HT,Fm Scanner,433mhz Device

 

...I live in Canyon Country and literally in a canyon, so my range is limited at best.

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11 minutes ago, axorlov said:

If you have to have thin cable, at least opt for LMR-240 or RG8X.

Great, that's the kind of info I need, thanks, I'm a newbie and don't know much (my head almost exploded with I clicked on that chart 😂). The reason for the long cable is to run it from my roof down into my office space.

So would this be a better option?

1) RG8x Coaxial Cable, CB Coax Cable, 50ft RFAdapter UHF PL259 Male to Male Low Loss CB Antenna Cables, 50 Ohm for HAM Radio, Antenna Analyzer, Dummy Load, SWR Mete

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RG8x is better than RG58 but is still terrible for UHF - spring for the LMR400; it'll give you a noticeable boost in performance. It's worth the cost: https://abrind.com/product-category/abr400-solid-ultraflex-assemblies/

I can't comment first hand on the antenna; but the Browing BR-6353 works well at GMRS for what it is, it's only slightly more than the TWAYRADIO brand: https://www.theantennafarm.com/catalog/index.php?main_page=product_info&products_id=3580&gclid=Cj0KCQjwkbuKBhDRARIsAALysV7PYMkBxYiCxyoQ5dSVENW9I2CnZc0eMgrFmNlvt_oP7ufbQQW9qdYaAiPhEALw_wcB. It's fully welded and pre-tuned, it's surprisingly tough for how cheap it is. I recommend getting away from Amazon when shopping for radio stuff.

Bonus points for the type N connectors too - while PL259's are also called "UHF" connectors it's because when they were designed UHF was anything above 30mhz; Type N is mechanically a better and lower loss connector, and are better for weatherproofing too.

edit:

Back on the coax; you're putting up a 7.1dBi yagi antenna, with 50' RG-8x you will lose 4.246db of that gain for a net system gain of 2.9db.

In contrast; with the LMR400 - you're 'only losing' 1.371dB for a net system gain of 5.7dB

For the hell of it - using RG-58 results in a net system gain of 0.2dB; it'd almost completely negate the benefit of your antenna to an isotropic radiator (which is below the performance of a basic dipole as it is already).

For reference; a basic dipole 'unity gain' antenna is 2.15dBi (aka 0.0dBd)

see: https://www.qsl.net/co8tw/Coax_Calculator.htm

Edited by JeepCrawler98
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11 minutes ago, JeepCrawler98 said:

Bonus points for the type N connectors too -

Yay, I am taking this seriously! Writing notes and doing research and I appreciate all the assistance and resources. Trying to avoid as many disappointments and do-overs as possible (a lesson I've learned my life- ask for help). 

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6 hours ago, JeepCrawler98 said:

RG8x is better than RG58 but is still terrible for UHF - spring for the LMR400; it'll give you a noticeable boost in performance. It's worth the cost: https://abrind.com/product-category/abr400-solid-ultraflex-assemblies

 

To give a little different numbers perspective, (on 70cm, not far off of gmrs), I had a vertex vx4207 feeding a comet gp1, via 17 ft of unlabeled cable that came with a Midland mount kit; swr was 1.1 to 1.  Measuring at the radio showed 43 watts;measuring again at the antenna end showed 23 watts. Swapped the Midland cable for  35 ft of abr400 (wanted some extra to get the antenna outside), and measured again...1.09 swr, and 35 watts at the antenna.

The changing cables cut the loss by more than half,  even with twice as much cable.

Edit: if we're aiming for 100% accuracy, using a dummy load in place of the antenna would be preferable...as I don't have a dummy load rated for the power, I was content  with a reasonable estimate on the loss

Edited by wayoverthere
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51 minutes ago, wayoverthere said:

The changing cables cut the loss by more than half,  even with twice as much cable.

Thank you for sharing your input and experience. The different perspective helped. I'm glad I posted here, gathering all these knowledge nuggets, so I can be confident that when I'm ready to order, it will be everything I need and nothing I don't.

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I have to correct myself, when I said 10 times reduction for RG58U I was thinking of 100 ft length of the cable. Still, 50 ft is nothing to sneeze about. Use LMR-400 if possible. It's a 3/8-inch cable, fairly rigid, and depending on how you're going to pull it, it could be a good thing. So, what everybody said, and the calculator provided by JeepCrawler98 is very useful tool. I totally agree. You're putting up Yagi, means you want to put all power you have in a small sector, so makes sense to not waste this power to heat the cable and surroundings.

I, myself, never use RG58U. For car installs, where the cable run is shorter than 10' and I need a thin cable, I tend to use LMR-240. Or RG8X if space is very tight, because it's more robust than LMR type. For home base I'd pull thicker LMR-400. It is a popular cable, available everywhere (I usually buy from DX Engineering, they have 400MAX which is an LMR-400 knock-off with a similar characteristics), connectors for it are no problem, and you can buy correct length with connectors already attached.

And if you're a newbie, you should seriously consider getting cable with connectors. Go to reputable vendor (Antenna Farm, DX Engineering, people will share their favorite places), order pre-made assembly with N connectors if the antenna has N connector on it. You can use N-to-PL259 adapter inside home and keep much better weather-proof N connector outside on the antenna.

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Progress update: Cable and Antenna on stand-by, the Comet-NCG (CA-F72GF @ HRO) and 18' of LMR 400 (25400F-NM-PL-18 @HRO). Now for dessert...which base(mobile) to get? I like the DB20-G in my rig, but I'm thinking something with more watts, as I am in the canyon. I know I'm new and sometimes feel like I might be getting in pretty deep, but I'm motivated and a quick learner. My goal is to have this unit in my home so I can talk to folks and I like to be able to use the unit as a scanner, too (for those dead-air moments 😉 ). Again, any suggests on the best unit to suit my needs, advise, recommendation, and yes, even criticism, are welcomed.

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The antenna gain will limit the frequency response across the full range of channels available as it will maintain a low SWR for 5 MHz on either side of the tuned frequency. As far as a unit to use for the base, I'd go with one that is rated at 50W on the UHF frequencies. Brand isn't as important as are the specs for receiver sensitivity, the higher the value of the number the better.  -115 is better than -110 or lower absolute value. The bandwidth affects transmit primarily as SWR has little to no effect on receiving.

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4 hours ago, BoxCar said:

The antenna gain will limit the frequency response across the full range of channels available as it will maintain a low SWR for 5 MHz on either side of the tuned frequency

I'm getting the idea that that antenna is the crucial piece here, height is might, is what I keep hearing. So thank you BoxCar for bringing up the SWR factor because that I haven't heard or considered, yet. I adjusted the SWR on my cb antenna and imagine it's a pretty similar process, correct me if I'm wrong. At the same time, I'm sure I can't use the same meter on a gmrs antenna, or can I, and would I need to?

As far as my base unit, I pulled back on the reins a bit, considering the antenna is key, I might as well see how my GM30 and DB20-G perform on the new antenna, which I could swap in/out of my rig depending on the circumstances, first. That said, using either the mobile (20watt) or HT(5watt) with the home antenna, would it be necessary to adjust the antenna (assuming I need to when I first install it) each time? I'm guessing once the antennas dialed in(like my cb firestik) there no reason to adjust it when switching devices, but I could be wrong (surprise, not the first time 😄).

 

As to the comment below, where can I find this info for my radios?

4 hours ago, BoxCar said:

Brand isn't as important as are the specs for receiver sensitivity, the higher the value of the number the better.  -115 is better than -110 or lower absolute value

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On 9/25/2021 at 9:53 PM, axorlov said:

You can use N-to-PL259 adapter inside home and keep much better weather-proof N connector outside on the antenna.

It'll be half in/half out. I've seen coax wrap-roll advertised, would it be a good idea to wrap the section outside that connects to the antenna? I would think it wouldn't hurt.

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8 hours ago, Papatree said:

Brand isn't as important as are the specs for receiver sensitivity, the higher the value of the number the better.  -115 is better than -110 or lower absolute value

This is what I found for the GM30

png-3e22b525-113f-4717-8354-b3162efd8cbc

and the DB20-G

png-e64d5c54-ea2b-4cba-ba1a-94bf27404cea

No clue if this is relative or what it means towards my project...

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12 hours ago, BoxCar said:

Brand isn't as important as are the specs for receiver sensitivity, the higher the value of the number the better.  -115 is better than -110 or lower absolute value. The bandwidth affects transmit primarily as SWR has little to no effect on receiving.

This is what I found:

DB20-G:

png-e64d5c54-ea2b-4cba-ba1a-94bf27404cea

GM30:

 

png-3e22b525-113f-4717-8354-b3162efd8cbc

No clue if this is relative or what it means towards my project...

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11 hours ago, Papatree said:

I'm getting the idea that that antenna is the crucial piece here, height is might, is what I keep hearing. So thank you BoxCar for bringing up the SWR factor because that I haven't heard or considered, yet. I adjusted the SWR on my cb antenna and imagine it's a pretty similar process, correct me if I'm wrong. At the same time, I'm sure I can't use the same meter on a gmrs antenna, or can I, and would I need to?

As far as my base unit, I pulled back on the reins a bit, considering the antenna is key, I might as well see how my GM30 and DB20-G perform on the new antenna, which I could swap in/out of my rig depending on the circumstances, first. That said, using either the mobile (20watt) or HT(5watt) with the home antenna, would it be necessary to adjust the antenna (assuming I need to when I first install it) each time? I'm guessing once the antennas dialed in(like my cb firestik) there no reason to adjust it when switching devices, but I could be wrong (surprise, not the first time 😄).

 

As to the comment below, where can I find this info for my radios?

You will need an SWR meter for the VHF/UHF bands (135 MHz - 470/512 MHZ) to set the antenna for optimal performance. The Surecom 102 is digital and used by many. It's less expensive than many ham meters and the analog pointer is usually more difficult to read when you are close to resonance. 

The table you posted shows typical values for a receiver. The 25 uV fgure is typically used and the 12 dB SINAD is a decent ratio of signal to noise. You want the adjacent channel and rejection numbers to be higher as in larger absolute values but those come with higher cost radios. And yes, the antenna along with height are the key pieces. 

As you start putting the pieces/parts of your system together you'll need to calculate your actual power being radiated. You will need to figure the amount of loss in the coax and subtract that from the gain of your antenna. You also need to convert the dB gain numbers from dBi to dBd by subtracting 2.15 from the antenna figures. Now you can subtract the cable loss from the antenna gain to get the correct number (or just read the power from the meter to see what is getting to the antenna).

As to the need to adjust the SWR when changing devices, you probably will need to. You should at least check and be certain things have not changed significantly as the feed from the handheld and the mobile may have slightly different impedance values (50 ohms is something strived for but not always met). I would set the SWR using the Base/Mobile and let the HH run with it as it isn't as important.

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You can hear the 650 repeater clearly, but your transmissions are just received as static.

In addition to all of these concerns, you should consider a BTECH 40 watt amplifier to give you the boost to be able to make it into that repeater (and maybe more?).

Or put the DB-20G in your truck and buy a 50 watt rig for your house?!

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If you want to be heard clearly - get an actual 50 watt radio that can do wideband with 5 kHz deviation. You'll transmit 50 watts on frequency, instead of amplifying spurious noise all over the band while still deviating less than you need.

You will probably find that with a good radio on a Yagi you can actually turn the power down to 20 or 25 watts once you've got things set up.

 

 

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So much great feedback from everyone, yet I'm still not quite sure which antenna would best suit me. Here is a list of the options I am currently considering: 

1) the height seems perfect for staying under the radar of the hoa (would be better with a N connector though, right?); $69.99 (BuyTwoRadios)

The Tram 1477 is a Dual Band 2m/70cm Amateur High Gain Base Antenna with a 150 watt power rating. This single section antenna is 43" tall with three 7" stainless steel radials and is pretuned for outdoor or attic use.

Dual band fiberglass base antenna
43" (1.09m) tall
Single section
1/2 wave VHF / 5/8 wave over 5/8 wave UHF
3 stainless steel 7" (17.78cm) radials
144-148 MHz VHF / 430-460 MHz UHF
Pre-tuned - no tuning needed
For outdoor or attic use
3.5 dBd (5.64 dBi gain VHF / 6dBd (8.14 dBi) gain UHF
Omni-directional
Fiberglass construction
Mast diameter accepted is 1 3/16" to 2 7/16" (30-62mm)
UHF female (SO-239) connector
Max power 150 watts
50 ohms
Available in white or black
Includes mounting bracket and hardware

2) may draw some attention, not that I'm worried since a lot of people have their Dish satellites here, and the height may give me the range I need; $169.99 (DX engineering)

Base Vertical, Type-N Female, Commercial/GMRS/FRS, 153-157 MHz and 460-470 MHz ONLY, NO HAM BANDS, Fiberglass, 10.10 ft. Height
Comet GP-6NC GMRS/FRS-Commercial Dual-Band VHF/UHF Base Vertical Antennas provide high-gain performance on the 153-157 MHz and 460-470 MHz bands. These superior-quality base station antennas feature a two-piece, heavy duty, UV-stabilized fiberglass radome for many years of reliable service.

With a high power rating in their class, these base station antennas are ready to handle constant use your high-power VHF/UHF radios. Although light in weight, they incorporate strong, easy-to-use, extruded aluminum and stainless steel clamp-on mounting hardware for masts from 1.25 to 2.50 inches. A weather-protected Type-N Female 50 ohm connector is ready for the user supplied low-loss coaxial cable.

3) compact but not dual band (has move to the bottom of my list); $109.95 (HRO)

COMET-NCG CA-F72GF
440 - 512 MHz Field Tunable Commercial Fiberglass Antenna 5.5 dBi 3.5 Feet N Conn.

440-512 MHz (tunable) fixed station antenna, 1.5:1 or less SWR:  10 MHz after tuning
Gain:  5.5 dBi
Max power:  150 Watts
Length:  42 inches
Weight: 2 lb 14oz
Connector:  N-female
Construction:  One-piece white fiberglass
Max wind speed:  135 MPH

4) Received many comments and recommendations, here and other forums, about the Yagi; $115.99 (DX engineering)

Moonraker Ltd YG27-35 Dual Band Hi Spec 2/70CM Yagi Antenna
Moonraker Ltd YG27-35 Dual Band Hi Spec 2/70CM Yagi Antenna is a professionally built Dual Band Yagi that requires only one feedline with a Type N connector.

Key features/specifications:

* Type: Dual band 3/5 element Yagi
* Frequency: 144-146 and 430-440MHz (does not perform on 146 to 148 MHz)
* Boom length: 45.28 in. (115 cm)
* Longest element: 39.37 in. (100 cm)
* Gain: 9.5/11.15 dBi
* VSWR: 1.5:1or better
* Power: 50 watts
* Connection: N-Type female
* Mast Size: 1.181 to 2.165 in. O.D. (30 to 55mm O.D.)

Looking forward to hearing y'alls options (pros & cons) on the above list. 

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I do not have personal experience with any of those antennas, but I can offer a few general comments.

1)  Tram is regarded by many as being bottom of the barrel for antennas.  Comet and Diamond, while being "amateur-grade" are definitely a step up.

2)  Note that #3 is not only single band but also narrow bandwidth and will need to be adjusted (trimmed) for GMRS.

3)  I'm not sure if a yagi is the right solution for you.  Yagis are directional antennas.  If there is *one* repeater you want to hit, then that would work.  Otherwise you'll need a rotator so you can point it in the direction of whatever you are trying to talk to.  Additionally, the one you have listed is narrow bandwidth, tuned for only part of the 2m and 70cm ham bands.  If it won't work well on 440-450 it's going to be even worse on GMRS.

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16 minutes ago, wrci350 said:

I can offer a few general comments

Thank you for your time and input. As for the Yagi, there's seem to be only one repeater, to the south of me, that I can hit, surrounded by hills and mountains on the other three side, so that's why I thought it might be a decent option. I could easily add a rotating component to it if I found I could hit other repeaters, later. 

Regarding number three, I'm a little sad to hear it seems to be the worse of all of them on my list. Not because it's only single band, (thanks for pointing out the narrow band too), and it may work the worse for GMRS, but that the guys at the shop told me that this was the "one" for me (after I shared everything I've shared here about this project).

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If your primary transmit function is GMRS - then skip the dual band stuff and go for straight up UHF GMRS that's focused on 450-470 MHz.  Dual band stuff is tuned for 2M VHF (@ 145 MHz) and UHF amateur (@ 440 MHz).  Your 467.xxx GMRS transmit isn't going to like a dual band antenna when you go to measure VSWR. 

You will still receive local VHF/UHF signals if you want to scan other stuff for receive on your GMRS antenna. If I was trying to transmit out of a canyon, I'd use a Yagi every day of the week for hitting a distant repeater from a tough spot. Even if your favorite Ham tells you to get a dual bander. Especially if you want it to work.

 

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1 hour ago, Papatree said:

Thank you for your time and input. As for the Yagi, there's seem to be only one repeater, to the south of me, that I can hit, surrounded by hills and mountains on the other three side, so that's why I thought it might be a decent option. I could easily add a rotating component to it if I found I could hit other repeaters, later. 

 

That seems like one of the perfect applications for a yagi... just given the tuning, that specific one may not be the best choice. 460-470 would be the range to look for; something a little wider frequency range, especially with a little wider bandwidth will work too...as long as it's a wide enough bandwidth to cover 462 and 467, you're in good stead...wider trades gain for flexibility, narrower may require tuning.

Maybe something like this? https://www.theantennafarm.com/catalog/index.php?main_page=product_info&cPath=191_193_258_977_978&products_id=3583

I currently have a Browning "no tuning needed" (410-490mHz) 5/8 over 5/8 mobile antenna, and it's like 1.15 or lower swr across 70cm and gmrs.

The issue with dual band is they're usually overlapping 2m ham and 70cm ham (430-450); something aimed at the commercial end of both (450-470 and ~150) might not be a bad option too.

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