marcspaz

@kidphc that's good to know that you had luck with moving your mount. I haven't moved mine yet, but when I get back to Virginia, if the dealer is done with some unrelated work, I'll pick it up and try sliding it forward. Worse case, I can swap the front and rear functions, using the back for UHF and the front antenna for VHF. And yes, both Jeep and Dodger/Ram vehicles cause a massive amount of RFI with most of the computers and controllers being in plastic cases instead of metal. I also can't run an HF Amp in my Jeep because anything over 100w below 50 MHz causes absolute chaos. LoL

It is definitely not just FRS radios. Every GMRS radio I have owned or used from Midland, has the call feature and a bunch of call tones. That includes the new MXT500 and MXT575. Come to think of it, every Motorola GMRS handle I have ever own had a call feature too.

I have to admit, when there are 5 kids in the neighborhood wracking that button nonstop for 3 hours, it gets old fast. Especially when you find out the kids are all in the same room.

The location that causes me trouble when everything is off is a lip mount 1/4 wave on the driver's side rear of the hood. It is only on channel 19 and only when I am stripped down and moving (unless someone with bad filtering on the wipers or alternator stops next to me). When I move the radio to one of the antenna mounts in the bed of the truck, I have no issues. But if I want to run amateur VHF/UHF and HF along with my GMRS radio, its not an option, so I stay off of channel 19 when possible. Otherwise, if I am on the repeater on 19, I just user my TSQL instead of running splits and leaving the receive side open. I am not sure where on the cowl your antennas are mounted, but almost anywhere on the cowl is a bad idea for multiple reasons. First it's way to close to the occupants of the vehicle. There should be at least 2.6 feet between people and the antenna so no one gets sick from RF radiation exposure. It cooks you just like a microwave oven cooks food. Second, my cowl and corner caps are plastic. So if you want to use a 1/4 wave antenna or another antenna style that requires a reflective ground, the SWR will be high and the performance will be very poor. A friend of mine with a Gladiator had installed his antenna in the same place (on the corner cap) and couldn't understand why hes receive was so poor with regard to audio quality and his range was terrible. While we were on a wheeling trip, I moved his antenna to the lip of the hood instead and his performance greatly improved. He went from only having about 1/2 mile of usable range to being able to talk to me simplex while 2 towns over. If you want to mount the antenna on the top of the rack, I strongly recommend making sure the rack is grounded to the bed and the frame with 3/8" or 1/2" braided grounding strap. Make sure the antenna mount is touching metal (preferably unpainted by using puncture screws). Also, because the roof is either plastic or fabric and the significant loss of reflective surface area, I would use a 1/2 wave antenna so it doesn't require a ground plane to work. A good NGP antenna will be about 13" tall plus about 1"-2" for the mount... so maybe 15" tall about the rack. This would be the shortest, BTW. Many are as tall as 32".

It's funny... I like Randy and I think he has a good sense of humor, but I was about 50/50 on if he was being sincere or not. This one was a hard read. LOL I figured for people who truly are new to radio and have zero clue about Ham radio (most of the world) it would help them as they read through.

Ham jargon for conversation or "contact". Stems from Morse Code / CW abbreviations that were carried over to voice communications.

I think I would just put a repeater in at my house and walk around with my HT before I spent money on a combiner. Then it won't matter what room I am in, if I'm in any room at all.

So, I never provided an update on my situation. I did some serious testing and I discovered that the noise issues I am having are directly related to my Jeep. I have been driving with my roof and doors off all season. The noise issues I have been experiencing are 100% due to some obscure airflow while the Gladiator is stripped down, causing static electromagnetic interference, and just with one antenna location. If I switch to my secondary antenna mount in the rear of the pickup bed or if the roof and doors are on, I have zero issues. That said and after experiencing a tad bit of frustration due to no fault of the gear, I will still contend that the top two over the counter mobile GMRS radios are the KG-1000G and the Midland MXT500. The MXT575 seems decent, too, but I have only experienced it from using one installed in another persons Jeep. Though, the MXT575 doesn't have a Compander feature (I don't see it in the manual or menus), which isn't a must, but it is a nice feature for Midland to Midland communications when both have the feature.

My primary GMRS antenna is a Tram 1126B mounted with a Comet mount on the side of the hood. Works fantastic. In hilly/mountain terrain, I get between 2.5 to 8 miles (VA) mobile to mobile and in flatter, more open areas I can talk 25-30 miles radio to radio. I have no trouble reaching well built, well placed repeaters 35-40 miles away with 5 watts. I also have the Comet 2x4SR antenna. I am not impressed with the SWR on the 467 MHz frequencies. It's acceptable (note great) on the 462 MHz frequencies and all of the covered amateur bands, but he antenna was designed for a cross platform user with FRS/GMRS channels 01 through 7 and 15 through 22. The antenna isn't meant/designed for good SWR on channels 8 through 14 or the repeater inputs. I have always had Jeeps with either plastic or fabric roofs, so mounting it high has never been an option for me.

As far as I know, you can't listen on two radios at the same time AND be able to transmit on either of them, one at a time or otherwise. Even a switch won't make that possible unless you are using two switches to completely cut out the other listening radio before transmitting. Duplexers are frequency split and directional. So, that is off the table. Diplexers are also frequency split, but support two-way communications on the same frequency. However, each side of the split typically has a vast enough frequency split that two radios can't transmit and receive on the same frequency on both sides of the split. Most of the time, they are band splitters. One side being VHF and the other UHF or one side is VHF/UHF and the other is HF/MF. Some T splitters (which are very affordable), but not all, would allow you to receive on both radios at the same time. However, you can't transmit without destroying the other listening radio. So, that really only leaves a T connector and two auto-sensing or manual switches. Keep in mind that there will be a small amount insertion losses, but you are facing potentially high expense. Frankly, even using 2 high-end auto-sensing switches is risky... I wouldn't do it. Keep in mind, I don't know everything and I am not aware of every device or method out there. This is just from my experience and training. Someone else may have a better answer.

Most men I know have a general philosophy of "when all else fails, read the directions."

I didn't know there different subscriptions. Learn something new.

It doesn't help that the FCC flagged the GMRS manual as being for the amateur radio. I think people may be using that as a reference.

That's not for a KT8900D. The KT8900D is an amateur radio. Not a GMRS radio. From the manufacturer.... Dual Band: VHF and UHF / 144 / 430Mhz TX amateur band version: 144-146 MHz et 430-440 MHz RX: 87.5-108MHz, 136-174MHz, 400-480MHz, 220-260MHz and 350-390MHz The QYT KT-8900D covers RX and TX 144-146MHz and 430-440Mhz in analog FM mode with 25 watts (VHF) and 20 watts (UHF) and VFO button for channel or frequency change.

That radio isn't compatible with GMRS. As pointed out above, its a Ham radio, not a GMRS radio. It can be modified to work on GMRS, but there is no soft-mod. It requires a technician or someone technically skilled with the proper tools to both add and remove some components from the main board. Once that is done, it needs to be reprogrammed. Given it costs about $45-$50 to do the mod (assuming you already have all the tools) and its only an $80 radio... almost no one does it. I would recommend you just buy a GMRS radio.

Technically, its a rule violation, not a law violation... but to answer your question, no, you are not authorized to have a simplex conversation on those input frequencies.

I agree... 50 watts is not needed. If you had not made a purchase yet and it fell into the "nice to have" category, that would be fine, but there is very little range difference between 15-20 watts and 50 watts. You probably wouldn't notice in the hills and mountainous areas. People who benefit from the additional power will be those who are out in open areas (water, desert, flat country/farm lands). Especially if they are using a large tower or have an elevation advantage and are trying to communicate with a party with a similar setup. As mentioned by @gortex2 if you are wheeling with people who are using handhelds, it won't matter anyway.

Correct. Being galvanically coupled to the HT is extremely unlikely. Galvanism must occur via direct contact with a conductive case or conductor on the case. Most HT's are made out of non-conductive plastics and other non-conductive materials. Due to the air-gap between the antenna ground inside the radio and the operator, combined with the resistance of the material of the body of the radio, the only way a human body can become part of the antenna system (which is dependent on the radio design and operating frequency) is via capacitive coupling. In a vast majority of VHF and UHF radios, the human body is in obstructive obstacle in the radiation path, rather than a useful part of the antenna system. Yeah, I got nothing on that one. LOL

I get it.

Agreed. For the best, most accurate results, an impedance bridge is the correct method. That is usually only worth it for someone designing a radio or antenna. For the average user, the labor and risk are to high. I also agree with this. The human body and the radio are part of a capacitive coupled counterpoise. Ehh... that can be handy, but it doesn't tell us if the antenna is balanced with the transmitter. I actually have an antenna analyzer that emulates having the antenna on an HT. You can rely on using a capacitive coupled counterpoise (by holding the meter) or you can add a wire to use as a counterpoise. The meter tells me the resonant frequency and the SWR of the antenna at that frequency. Most antennas I have tested have a 78 ohm impedance for their advertised center frequency. Some as low as 73 Ohms.... so a 1.5:1 SWR. The worst I have seen was 250 ohms about 5:1.

So, I usually understand what you are saying and typically agree with you on technical issues, but I am seriously missing something here. Are you implying that there is no way to measure the SWR of an antenna that screws to the top of the handheld radio? Or are you implying there is no way to to measure the SWR while the antenna is on the handheld? Or are you implying some other type of measurement can't be done?

@kidphc I have one of the inexpensive surecom units and it is extremely close in accuracy to my very expensive commercial meters. I would use it with confidence.

Why would you say this?

I fell for the advertising for the Abbree antenna too. I kept it because I am a Ham and can use it on amateur radio frequencies. On the GMRS 462 MHz frequencies, the SWR is 2.6:1 and on the 467 MHz frequencies, the SWR is 3.1:1. I definitely would not use it for GMRS. It will perform terribly and with prolonged use on the repeaters, you may damage your radio.

Is this while mobile or are you walking around/standing outside? Just my opinion, but I doubt any other antenna is going to help, even if it is advertised as having more gain. Every 3 dB is one signal unit. If you are on the very edge of the repeater where you are just barely out of range, you need to increase your effective radiated power to impact the receiver on the repeater 3 signal units to "possibly" be heard and understood. That is gain of anywhere from 9 to 12 dB gain... equal to about 50 watts of radiated power from your handheld... and that is assuming you are just barely out of range. It's not gonna happen. If those "dead spots" are due to terrain blocking your signal, being too far below the line of sight horizon, radio frequency interference, heavy woods or several buildings (or any number of other issues)... you won't be able to boost the signal enough.