mbrun

I bought some inexpensive equipment to do this and have done it in the past but I do not do it regularly. Years ago I purchased a large lot of high-capacity D-Size rechargeable batteries that I ended up seriously questioning their capacity. That was a motivator to buy some hobby-grade items for this purpose. I confirmed the batteries were only a little over 50% their rated capacity, even after break-in. They all got returned and replaced with a different brand and model. The alternative lot all tested to 90% and greater of rated capacity. Below is the unit I used. It is capable of measuring Volts, Amps, Amp Hours and Watt Hours, in and out of the battery. While it is not a laboratory grade instrument by a long stretch, it is good enough to get you in the ballpark. Michael WRHS965 KE8PLM

Congrats! You must be testing rubicon’s repeater. Welcome to myGMRS. Michael WRHS965 KE8PLM

Extending the length of a coax should not typically raise the average SWR from a properly tuned antenna. If the primary and extension cable and connectors are good the only thing you should anticipate is average SWR going down bit (how much varies with length). However, any mismatch caused by impedance differences in the cable, connectors, adapters and antenna can and will manifest themselves in the form of elevated SWR readings. For example, If I were to add a UHF barrel adapter in-between two otherwise good working short cables, I may see the SWR go up a GMRS frequencies as compared to use of only one cable. If I switch to a single cable of the same aggregate length the SWR will be lower. The frequency of test can result in different values based on cable length. Consider averaging your readings across the GMRS frequencies and see what you get. If you owned a NanoVNA and new how to use it you could spot issues with the cables and adapters more readily. One last thing, RG-8X cable has lower loss than RG-58. So if you separately compared the SWR of a given antenna with perfect 25’ samples of each of those cables I would expect the SWR on the RG-58 to be slightly lower because it has higher signal loss. Michael WRHS965 KE8PLM

There is nothing improper, in-appropriate about the presence of an external grounding terminal on a piece of equipment. The scope of the rules of the NEC do not regulate how a piece of electronic equipment is manufactured. The NEC covers things of an electrical nature and how they installed when they are installed as a permanent fixed part of the building. If the US most products feature a UL listing which indicates they have been demonstrated to comply with safety standards associated with their listing. On such standard would be one that indicates products that are not double insulated (according to UL definition) must have a power plug feature a grounding conductor. And for your safety, you should use it. Both NEC and UL standard separate things, but all about safety of life and property. Neither effectively cares about nor deals the performance of your system, outside the scope of safety. Complex electronics (including all variants communication systems including radio) can and do have special grounding and bonding needs in order to achieve highest performance out of your system. While challenging at times to get right, none of them necessitate violating the NEC regarding grounding. The external ground lug on a piece of equipment is not intended to replace the use of the third-wire connection on the power cable, but to supplement it for additional reasons. The TIA for example has supplemental standards (not NEC) for the addition of completely separate grounding systems in a commercial building for the exclusive use by the communications equipment that is distributed though-out the building. This system is sized correctly and connected to the building’s grounding system at one point only and in a fully code compliant way. It is used to reduce voltage potentials between distributed equipment to levels that ensure that equipment performs optimally and is not adversely affected by other equipment within the building. In a radio shack you have need to minimize voltage differences and ground loops between equipment at RF frequencies. When you have that problem, you will never get rid of them by just plugging in the safety ground on your equipment. You need a more specialized low-impedance bonding system to these. A properly implemented grounding system will never violate codes nor best practices for safety of life or property. A well implemented purpose-built supplemental system will yield the best possible performance from your equipment. Michael WRHS965 KE8PLM

Yes I am familiar with your scenario. Wouxun took an effective cost savings short cut to adapting their amateur radio for GMRS use. Rather than changing the firmware that regulates the user interface, they implemented logic in the firmware to prevent the radio from doing what it is not allowed to do per FCC. This is true for all but one of their radios I have tested. Michael WRHS965 KE8PLM

Did you use a dummy load instead of your antenna when checking your power? If not, odds are good the power number you are getting from your SWR meter is inaccurate. I personally have experienced power readings that have been off by as much as 43% when using an antenna versus a proper dummy load. I own a 1000G also and have previously tested it with power meter and dummy load. I found the radio to be within 5% of its rated output. In fact, each of the Wouxun radios I own have tested to within 5% of their rated output when properly tested. Michael WRHS965 KE8PLM

Yes, I use surge suppression between the wall outlet and radio equipment, but I do not bypass the electrical ground. Surge suppressors may have two forms of surge suppression, common mode and differential mode. If both are present in your suppressor and it is not grounded, only the differential portion of the suppressor does any work. Therefore you would have some protection, but not the full protection afforded by the device. One option that may deal with your scenario is to install TVSS in your panel so you can shunt the surges that originate from places other than the branch circuit in question. At the panel you have the ground readily available. Michael WRHS965 KE8PLM

I stand corrected. I pulled the manual for the radio and see that now. Thank you. Michael WRHS965 KE8PLM

No. The Rhinos as I understand them have fixed antennas which means no options for a better onboard or even an alternate external antenna. Michael WRHS965 KE8PLM

Welcome to myGMRS Chris! The Rhino radios are simplex radios, which means they are designed to communicate directly with each other using a single shared frequency. They are not designed to work with the aid of a full-duplex repeater which uses two frequencies and is so common in GMRS. So, you will need repeater capable radios, something like the Wouxun KG-805G or KG-905G, if you wish to use a repeater. The Retevis repeater sold here on the myGMRS site is a cost-effective portable solution that may be beneficial to you for your needs. It can be powered from an deep cycle marine, AGM or gel cell type battery among other 12v power sources. Batteries can be charged and maintained with a solar panel and charge controller. Some solar panels are available now that can be rolled up for transportation much like a roll of wrapping paper. Others are rigid or foldable panels. Lots of options on the market. You will always need a battery when using solar so radio works when it is cloudy and at night. The battery needs to be of sufficient capacity to operate your radio for what every duration you need it to in the absence of good sun. Your panel needs to be sufficiently sized to recharge the battery with available sunlight. GMRS radios are considered line-of-sight radios. Basically, if the two antennas can see each other, it is almost guaranteed the connected radios can communicate. Put obstacles between them and the range will reduce, in most cases quite dramatically. Antenna height is king in the GMRS world. The higher you get your antenna the better your chances of communication since higher generally means fewer obstacles. When using hand-held portable radios in conjunction with a repeater and antenna mounted high you can be assured of greater distances. I live in an area that is 60% trees and only slightly rolling. With an antenna at 56’ at home, I can communicate reliably to and from an HT out about 2-3 miles, and to a mobile radio out 4-8 miles. From the base radio I can communicate through repeaters that have much antennas at much higher elevations than I out to about 18-50 miles. The higher the repeater antenna, the better I can hit it. Hope this helps. Again, Welcome. Michael WRHS965 KE8PLM

To maintain a typical lead-acid battery at full charge, without overcharging it one needs a DC power source that provide a pretty consistent 13.5-13.8vdc (at 68F) https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery. The typical electrical system in a car and the typical power supply used for power supply mobile radios in the shack are both designed to produce this voltage. If LA batteries are fully charged they can readily be connected in parallel with a radio and power supply (exactly how a car is configured) so it is online and ready for uninterrupted immediate use with any loss or AC power. One consequential issue with this arrangement is that rare time that you end up deep cycling the battery. You could blow a fuse on your power supply when AC power is finally restored if the battery draws more current than your power supply can deliver. For prevention, switch off the power switch on your power supply when AC is lost and then plan to switch the battery over to a smart-charger battery to bring it back up to full charge after power is restored. An A-B switch could be an asset to you for this. I would not use a UPS as the means to provide long-term backup power to a radio that natively and efficiently already operates on 12vdc power already. I would perhaps if I only needed 10-60 minutes of backup. UPS cannot compete with the efficiency of a battery connected to DC operated device. I would save the UPS for powering those critical things that can only be powered readily by AC. Michael WRHS965 KE8PLM

You might very well be surprised and learn just how little difference there can be in usable range between using your 5W HT with a mobile antenna, in contrast to the same setup with the added amplifier in between. I still operate the HT with a mobile antenna and have good success working repeaters that have their antenna at good elevation. You may find you’re in good shape already. Michael WRHS965 KE8PLM

All electronics will handle extreme heat for some period of time, but heat is the enemy of electronics. How long is a complete unknown for every product. A radio sitting idle or in receive only mode will not generate as much heat as radio will when transmitting. When the radio is put into a closed compartment it will raise the ambient temperature around it constantly causing the radio to get even hotter when operating. Again how long it will last is a completely unknown and a complete guess. You may find that radio will last as long as you care to own it under your conditions. Ask yourself if there is a way to force some air through the console with something like a muffin fan when you get to the point you are transmitting on the radio a lot. Michael WRHS965 KE8PLM

That is called “desense”. The radio that is transmitting, although transmitting on a different frequency, is actually desensitizing the receiving radio thus rendering it incapable of extracting the desired signal. It is the same effect you and your eyes suffer when you look in the direction of a bright light. Suddenly your eyes cannot make out the detail of the less bright items around you until the bright light is gone. The better the receiver design is within the radio the less it is affected by this. As Skyline said, put some space between the radios so the off-frequency transmitting radio is “less bright” to your receiving radio. Michael WRHS965 KE8PLM

Not sure I understand the question. Otherside? Perhaps you can clarify. In the scenario I presented, I was imaging one vertical antenna on top of the mast, at say 40’. Then, lower on mast, perhaps at 20’ feet, another vertical antenna. The lower antenna could not be mounted collinear with the top antenna as it would need to be offset from the mast and coax that serves the upper antenna to work correctly. But being below the upper antenna as it would be, there would be some isolation that would occur. Not perfect, but closer to the null of the donut formed by the upper antenna and vice versa. This arrangement would be far better than two antennas mounted adjacent and parallel. Comments? Michael WRHS965 KE8PLM

Wouxun KG-UV9P and KG-UV8H both have built-in cross-band repeater function. I own both of them. Michael WRHS965 KE8PLM

I can confirm that if you select text is certain cells that you can right-click and copy the highlighted cell contents. Does not work on all cells. Michael WRHS965 KE8PLM

I cannot speak to whether some form of alkaline case may be in its future, but a first glance it does not look like the existing battery case width is conducive to a AA battery pack version. You may wish to have battery eliminators so you can operate the radio off an automobile or deep cycle battery or solar cells. You may have to resort to having extra rechargeable battery packs on hand, your drop-in chargers and some 12v power adapters so you can recharge the batteries using solar cells, automotive or deep cycle batteries. Michael WRHS965 KE8PLM

Sadly, any overlaps or gaps that would result from overlaid circles would be fictitious at best. Coverages on maps today are shown as circles out of simplicity and convenience. It may or may not represent maximum tested range in one or two arbitrary directions. Coverages are actually jagged, random, irregular shaped blobs in the real world, they are only circular in outer space. I experimented with one just this past week in the mobile. Someone had informed me coverage was about 13 miles. Unreliable coverage began at about 3 miles and I lost complete comms at about 5 mile in my direction of travel. You can see that the circles would quickly become misleading if 13 miles were the official distance listed on the map. But I do get it, seeing the circles is nice visual aid. Michael WRHS965 KE8PLM

Started GMRS with Southwestern Bell GMRS HT back in early 2000s. This it looked like this: Then onto Midland GXT1000: Then first repeater capable GMRS HT radio, a Wouxun KG-805G: Then added a Wouxun KG-905G to the toolbox. Michael WRHS965 KE8PLM

A topic that I have heard brought up on amateur radio is the phenomenon that while sitting at or passing through and intersection you loose the ability to receive usable signals from some repeaters. This is theorized to be the desensing of our radios from the various traffic control, cameras, sensors and other electronics now permanently residing at many intersection and that are producing RFI. While I do not know that I have experienced this, I was curious if any of you have. If so, let’s hear about it. Michael WRHS965 KE8PLM

I was really looking to go to it this year.[emoji53] I spent the first 30 years of my life in Dayton. It was a big attraction and news worthy event. However I was not a ham at the time and little expendable income so I never attended. I did my testing and obtained my license at DARA headquarters. Wow, what a nice facility and good group of people. I am a member of the Milford Amateur Radio Club and have volunteered to assist with the Cincinnati Ham fest August 28th (CincinnatiHamFest.org). Yeh it will small in comparison but I am still looking forward to it nonetheless. Michael WRHS965 KE8PLM

You likely have two things that can explain that. First is the radiation/pickup pattern you just surmised. Second, the Ed-Fong GMRS antenna is technically a dual band antenna, and by design will work well in the MURS portion of the VHF band as well. Perhaps because air band frequencies reside in the 50MHz below that the antenna is more sensitive to them. BTW, I just checked my Ed-Fong GMRS roll-up with my VNA and it shows an SWR of 1.2 in the MURS range. Michael WRHS965 KE8PLM

Every bit helps, but not significantly. Let me help by giving you a very, very crude illustration. A 5 watt radio provides 37dBm output. A typically radio has a receive sensitivity of -120dBm (the lowest level the radio needs to produce usable audio). That is 157dBm of difference. Now, imagine all 157dBm is lost in only 1 mile due to all the obstructions in the path, for an average of 1 dB loss per 33 ft. So now lets say you increase your radio power from 5 to 50 watts. That is an increase of 10dBm (37 to 47dBm). Ok, so now that you have increased your power 10 fold. How much further will you get if you assume the same linear average path poss of 1 dBm per 33 ft. You got it, 330’. So in this example, you increased your power by 10 fold yet your effective distance increased only from 5280 to 5610’. Now, if you were not battling the losses from all the obstructions in the path and went into outer space that same 5 watts would get you 225 miles, and 50 watts would get you 700 miles. There, signal level will drop based purely on inverse square law. The point I am trying to illustrate here is that presence of attenuation of signal caused by obstacles in the signal path plays a significant role in how far your signal will and will not travel. It takes a lot of extra power to “burn” through the obstacles. Much better to raise the antenna to remove the obstacles from the path in the first place. I hope this helps a bit. Michael WRHS965 KE8PLM

Thanks for sharing that tip for all the soon to be new owners of the 905. Michael WRHS965 KE8PLM