BoxCar

I don't like disagreeing with you, but your statement is both true and false. Radio engineers, at least the ones I have met, do test stock antennas with their designs and write specifications for the "rubber ducky" that provides the best match. Many times this results in one that has to be manufactured to specifications that existing units don't meet. Why else would LMR radios specify different antennas for specific radios operating in the same band? One size doesn't fit all.

Welcome to the forums.

Higher power means better coverage in the same area as the increased power penetrates obstacles better, but the area served remains the same.

And it does have a dark underside.

Does that answer come under RTFM?

If I understand you correctly, the two radios will NOT talk to each other on that frequency pair. You need a third radio in the mix, the repeater. A repeater consists of two radios set to receive on one frequency and then transmit what is received on the other frequency. What you are trying to do is use a split channel where the radios receive on one frequency and then transmit on the other frequency but not simultaneously. In order to do this, the frequency assignments in one of the radios must be reversed so its receiver is on the other's transmit frequency.

In a nutshell, Standing Wave Meter, CQV SWR120 Digital Power Meter, 240x240 Full Color LCD Display, 1.8Mhz to 54Mhz, 0.5W to 120W. I just received this meter and plugged it into my radio. I was impressed with the easy to read screen even with its small size. QST has a review on the meter in the Nov. 2023 issue and they show it is quite accurate out of the box. Amazon lists it for $79.02 but a quick search got the price doen to $45.02. I paid slightly less from a Chinese store, just over $41.00. It sure beates my Surecom SW-102.

Does your ham club have a repeater? Ask if a GMRS one be added to the site.

My suggestion is to check the ARRL website for ham clubs near you so you can see what V/UHF bands are used in your area. Yes, the Wouxun does cover the amateur bands available to users holding a Technician license or higher, but you aren't going to reach many without using a repeater. Most amateur repeaters are VHF or 70cm (440 MHz), with a few at 220. Some excellent ham radios in the handheld form are the Yaesu FT-4X and FT-65. These can have the GMRS and MURS channels enabled by entering a code through the keypad, but that modification makes the radio non-compliant in all services. That doesn't mean it isn't done; it just means the radio is non-compliant for use outside the ham bands.

A 45W mobile can be had for about the same price with fewer points of failure. What's not shown in their ad is you'll need a hand mike for the radio as trying to hold and key a HH while driving is very cumbersome.

I don't believe i will work as drawn. You need to charge the batteries with a 48V+ source. Now, could the chargers be in series, I don't know but our resident P.E. Mr Shannon may be able to answer.

Yes, there are effects from what I learned was a parasitic radiator. The amount of effect is determined by the percentage of a quarter wavelength distance between them. At a quarter wavelength the parasitic radiator will boost the signal from the transmitting antenna and at a half wavelength will have no effect. At 1/8 wavelength there will be maximum affect as the reflected wave will be in full opposition to the radiator. A simple visualization can be done by drawing a full wave on a piece of paper and then moving a mirror representing the second antenna along the X axis, You will have a visual representation of the affect of the two antennas.

A better power supply (IMO) is a Mean Well LRS series unit. A Mean Well LRS-12-360 supply can be bought from Amazon for less than $40 and can supply the 13.8V needed by the radio with medical grade power. It doesn't have the fancy meters and you'll need a cheap volt meter to adjust the output voltage but once set you can forget it for the next 20 years or more. I know of several public safety sites that use these supplies in their repeater sites.

There are several brands that have a good reputation for quality units. Spending a little time perusing the various threads will give you the information you want.

I'll weigh in on this on WRYU400's side. The critical antenna is always the higher frequency one. A quarter wavelength distance results in the longer antenna acting as a reflector increasing the signal lobe opposite the reflector. As the higher frequency antenna is not at a distance that would resonate with the lower frequency antenna it has minimal effect on the higher frequency antenna. The articles Mr. Shannon is referencing are focused on antennas in the same band.

JamesBrox - If you are considering putting up a repeater the first thing to consider is what do you want to do with the repeater. Is it primarily for local ( 5-10 mile) service or do you want a longer range? Range will be the primary cost consideration. More range, more expensive - period. Local service can be handled with one of the little 5 watt units on a 35 foot high antenna. Longer ranges mean high cost towers going up 50 or more feet and higher output transmitters. A 50W GMRS transmitter unit will cost new around $1500 - $2000. The tower another $5 to 25,000 depending on height and construction. As you are in Florida, think highest cost due to hurricanes. Then there is the antenna and feed line costs. You'll want an antenna with gain, 3 to 9 dBd or better. The transmission line should be hard line, not normal coaxial cable like RG8 or LMR. Hardline cable starts around $4 a foot so 50 feet is over $200 plus connectors. The antenna ranges from around $100 to over $2500. A 35 foot mast can be aluminum or fiberglass, you can even make one from PVC pipe. It will need guy wires to keep it straight and vertical in normal winds but will have to be taken down during a hurricane. You are still looking at spending a couple hundred dollars for even PVC. The Ed Fong J-Pole antennas work, but have no gain which means any power losses from your feed line and antenna mismatch won't be compensated for.

The specifications for the unit show it measures up to 454 MHz in the UHF spectrum which is below the frequencies used in GMRS. It will however, give you an idea if there are interferers present.

The radio's power leads are fused so use those leads. Just put connectors on the end of the leads.

It won't work though. The transmitter will interfere with the receiver as they are both on the same frequency. The site would need to be a store-and-forward configuration to use a single frequency. Simplex, by definition means a single frequency is used for both transmit and receive between two stations alternating transmissions.

The 10 AH LiFePo4 battery will run the radio for several hours with 80% of the time listening. It could stretch up to 24 hours depending on how much time is spent transmitting. A better choice for a battery is this one from Amazon - https://www.amazon.com/XZNY-LiFePO4-Rechargeable-Suitable-Emergency/dp/B09QPX38GG/ref=sr_1_12?crid=PZ83AN1KXVYM&keywords=16ah%2Bbattery&qid=1697761072&s=electronics&sprefix=16ah%2Celectronics%2C145&sr=1-12&ufe=app_do%3Aamzn1.fos.18ed3cb5-28d5-4975-8bc7-93deae8f9840&th=1. It has twice the capacity at about 2/3rds the cost of the Dakota battery you chose. The Woxun radio you like is out of stock and a better choice (IMO) is the Radioddity DB-25G with slightly more power but many more empty channels to store repeater configurations in. The complete radio package from Amazon is $210 including antenna and mag mount. Add a lithium charger https://www.expertpower.us/products/epc125-5a and you are set. The only thing missing are the connectors for the battery to the radio. You'll need 2 1/4 inch quick disconnect spade connectors crimped to the radio's power cable.

A lot of fun and wierdness.

A better radio choice is the DB-25G (Radioddity DB25-G GMRS Mobile Radio | 25W | Quad Watch | UHF VHF Scann) and for portable power, a battery box with a LifeO4 battery is much better. The radio draws about 8 amps while transmitting so a 1- 16 AH battery for less than $60 is a better choice. You can put in a box, like the Apache 3800 (3800 Weatherproof Protective Case, Large, Black (harborfreight.com)) and a cigarette socket (Amazon.com: CERRXIAN 12V/24V Fixed Thread Cigarette Lighter Socket Extension Cable,20A 13AWG Waterproof Cigarette Lighter Female Socket Replacement Cable-0.3m/1ft : Automotive) sets you back about $120.00. You'll need to put connectors on the cable to connect to the battery, but the socket can be used to both power the radio as well as charge the battery. All total, including radio is around $250 without the antenna.

Try calling any of the commercial radio shops. There are several in the DFW Metroplex.

Too mean for them?

you can do that search on the fcc website ULS.