OldRadioGuy

Thanks for clarifying that I meant x-band repeater operation only within the ham bands. I was not suggesting to mix ham and GMRS signals.... which is not even possible with the radios I mentioned. Well, it's possible, but not without some serious hacking. Vince

I got a kick out of the post that said try Ham radio for "social radio". One of our local repeaters has a group of regulars that are on there every night. Sometimes it's about like a lunch table at a high school. They BS about gun stunts, recreational explosives, debates about army tanks and munitions, and crazy stuff. Sometimes entertaining and sometimes disturbing. :-) Other times it's mostly technical radio talk. Lately it's been a lot of talk about amateur satellite comms. I think GMRS tends to be more of an outdoors crowd - which I like. I rarely transmit on the local Ham repeater. Vince

The other way is to get a Ham license and do a cross band repeater on 2M/70cm. Several mobile units and the Wouxun UV9? will do cross band repeat. Cross band repeaters do not require duplexers so much much easier and cheaper to do. I know - the problem is that your camping buddies and family don't want to get a ham license. That's why I have GMRS :-) A different way to address the problem is better antennas. I have a couple Nagoya 771 and Smiley Super Stick antennas for my Wouxun 805G's and they do help. Terrain is a huge factor so always good to be aware of it. Maybe have a look on Gmaps before going camping just to have a general idea. Vince

I totally missed that the "remote head" causing interference is completely wireless. If the wireless unit is entirely causing the interference you're probably stuck with it. The guilty unit is transmitting GMRS noise and I can't think of any way to change that without going inside. Obviously that's not an option. If there are no wires connected to the remote head I don't see any way to mitigate the radiation while allowing it to still work wirelessly. You could try locating it in a nook where it's partly shielded from your GMRS antenna but that's pretty tricky. I guess maybe you could put the head unit in a metal box when not actively using it. I wouldn't assume that the "head unit" is out of spec because it's very close to a very sensitive receiver. I used to do EMI compliance testing and all digital devices make tons of RF noise. Sporadic noise gets much more lenient treatment than steady signals. So these can exceed the limit for steady signals (it's called quasi-peaking) This sporadic noise does bother our radios so not a good deal for us. It's a very noisy RF world we live in today. It's amazing the the problem is not even worse. Vince

A simple way to use the 805G for repeaters is to just change your display (menu 19) to frequency. Then you can see the freq for repeater channels and just set the TX tone as needed. You generally don't need the RX tone unless you are getting interference. The channel number is still displayed - just smaller. It is actually the memory location but it's the same as the channel number for 1-22. This scheme works pretty well and it's easy to toggle back to channel name using menu item 19. I suppose if you use a lot of repeaters around home getting the software and programming channel names for each makes sense. For occasional repeater use and travel my simple scheme is pretty good. Vince

The lower level ham tests require more memorization of frequencies and things. So there much more to memorize and not so much to understand at a deep level. The higher level tests have much more general electronics theory. If you have a decent background in electronics they are pretty easy. I'm sure there are tons of good tutorial videos on youtube. I've had my extra class since 1985 so I used these things called books. Vince

I have both ham and GMRS. I use my 2M/70cm ham antennas with no problem on my Wouxun 805G radio. The SWR is well below 2:1 which is good enough for me. (That's less than 10% reflected power.) Of course, I do not connect the ham and GMRS at the same time. My ham radio is a Yeasu mobile 2M/70cm and I don't usually use it while under way. I use it more at camp but often do not get any replies on the repeaters. Truthfully it's been rather useless. The GMRS is very useful for vehicle to vehicle comms while traveling together. Most of our fishing and camping buddies (and my wife) do not have a ham license. So GMRS or FRS is the way to go. Vince

I have an icom 718 that is made to work with the AH4 random wire auto tuner and it works great. Because the feed point is actually at the tuner it works very well. You can use a variety of wire lengths or even a vertical element. Might be something to consider. It's not super cheap but it works very well and is very convenient. Just push the button and you're tuned. Vince

Hi, I'm from the HOA and we're coming for you! Just kidding. I use the icom AH4 random wire auto tuner with my icom 718 HF rig. It really works great with 42' of wire on 80-10 meters. You have to use a wire length that is not resonant on any frequency that you will be using. You can use shorter or longer lengths depending on the bands you want etc. The reason this tuner works so well is that it goes outside and there is NO transmission line between the tuner and the random wire. The random wire feed point is right at the matching unit - and the voltage can be rather high so mount it out of reach. This is why it needs to be an auto tuner - because it has to be mounted out at the antenna feed point. It's not a cheap solution but it works very well and is very convenient. I have no complaints about it. Vince

Maybe we should set up a survey for this.... I'm just curious how many people primarily use GMRS on repeaters and how many use them mostly simplex. Also, if you do mostly use a repeater, is it mostly for "social radio"? or more for necessary communications? We use them mostly simplex mode for direct communication in outdoors situations or traveling together in separate vehicles. I occasionally use repeaters but not very often. Maybe if one had better local coverage here I would use it more. I've been a ham for 35 years but my wife and fishing buddies are not hams - so FRS/GMRS is more useful. What is your primary use or purpose for getting into GMRS? Vince

SWR versus return loss or reflected power. People get obsessed with 1.2:1 or very low SWR but it's not that big of a deal. A 1.9:1 SWR is a 10dB return loss meaning that 10% of your power is reflected back to the radio. This is not that bad.... and not that rare. In my book anything 2:1 or better is pretty decent. Even a 3:1 SWR is a 6dB return loss meaning that 25% of your power is reflected back to the radio. It does not mean that this power is completely dissipated in the finals of the radio either. Radio outputs are not often that close to a 50 ohm Z. So some of that gets re-reflected. Transmitters are designed to work into a 50 Ohm load. That does not mean they look like 50 Ohms. Of course for a 10KW radio station it's a different matter. These numbers get kind of big. Vince

I think the antenna itself is your limiting factor. It's basically a "rubber duck" for a car. I've read posts about these antennas being close to worthless. If this antenna works OK for your day-to-day use then just keep it as is. You could have a good mag mount for the times when you need more range. Just stash it in the back and put it on when you need it. Vince

See what happens if you reconnect the GMRS antenna but disconnect the car stereo antenna. It's very possible the stereo is radiating junk from its antenna. If it's common mode radiation (which is likely) a ferrite on the stereo antenna coax will help. This stuff can be very difficult to track down. The car stereo is probably not even violating any RFI standards. It's just so close that it doesn't take much. Vince

If your speakers were too high of an impedance you just wouldn't get much volume. No harm would be done to the radio. If the speakers Z was too low AND you really cranked it up loud maybe you could damage the radio from excessive current but pretty unlikely. Most audio output chips are temperature protected anyhow. You could just add 4 ohms in series which should satisfy the min Z requirement. Vince

That's true. You can program the names for local repeaters. Then when you travel switch the display from "name" to "frequency" so you can easily select area repeaters by frequency. If you don't have the cable and software putting the names takes some patience but it's not complicated. Vince

Make sure you have a ferrite or two on ALL wires connected to the car stereo. Especially the radio antenna cable. I'm sure it's not easy to access these things but you have to do all the wires or it won't help. Vince

Why don't you just get a couple 805G's and test them. They are about as good as you are going to get in a modest priced GMRS radio. The next step up is a huge leap in price. The antenna is a significant factor. If you can sub a Nagoya 771 or a Smiley Super Stick things improve quite a bit. My experience is that my 80G's perform similarly to my Yeasu ham HT. This is based on working repeaters 15-20 miles out. I always find that terrain is the limiting factor with ground to ground comm on GMRS. It's usually "all or nothing" so small changes in sensitivity wouldn't change much. Vince

If the antenna was anything close to a match to start with the 50 ohm coax length should have little to no impact on SWR. I would assume it's the connector and try doing it again. For those of you familiar with the Smith Chart.... If you have a load that is at or near the center of the chart, 50 Ohm coax just rotates it around the center point. So the SWR should not change appreciably. I can't imagine that the coax would have been part of the matching scheme because it would have to be other than 50 Ohms to make a 1/4 wave transformer. I think that would be highly unlikely. Vince

You could start by trying a dummy load at the antenna connection. That would rule out the coax and connectors if the SWR looks good. Vince

That's a cool looking unit. Some of the Hams use batts etc. from bioennopower.com to make their own power sources. I hear this is good quality stuff. One of the Hams has a family business that builds these into systems and sells them. They are called https://shack-in-a-box.com When I say "family business" I mean the kids actually are involved. All of the kids are extra class hams. Powerwerx also has some components but some of the hams say their chargers are noisy. They generate more RF interference than the bioenno chargers. Vince

Cable Radiation I just want to point something out. Eliminating the cable reduced the radiation. But does this mean it was bad cable? No. The shielding of this cable is probably just fine. You could replace this cable with the finest quality and it would still radiate just the same. This is because it's common mode radiation. The whole cable is a sort of antenna. Only a ferrite or better grounding system would reduce the common mode radiation of the cable. Don't go out and buy a more expensive cable to solve this problem. Vince

I think the removable antenna is just as big of a deal as the small increase in power going from a 2W FRS to 5W GMRS hand held. You can plug a GMRS radio onto a mag mount antenna in the car. Or you can choose a bigger, better hand held antenna like a Smiley super stick 465 or a Nagoya 771. A better antenna does not take more current out of your battery like a higher power radio either. And it also helps the guy on the other end if your antenna has some gain. Vince

There is no such thing as too much ferrite so get the biggest ones you can tolerate. You can use on or more on each cable. Usually placement along the cable is closer to the source but it's not critical. Ferrites are charactertized but frequency range. So you want want intended for 460MHz. If you go on digikey there should be a filter to select ferrites by frequency range. It's not an exact thing. Just get close. You've seen ferrites on some USB cables and they are like the size of a Pecan or a bit smaller. So this is a good size to look for. You probably want "split" ferrites which can be opened up and placed on the cable without removing connectors. They have a hinged plastic shell that snaps together. They can easily be moved or swapped around to try different locations. On the power line you can pass the leads through twice if there's room. Just loop right around and come through again the same direction. Any ferrite that is intended for UHF will probably work. Here is an example of one to check out. https://www.digikey.com/en/products/detail/fair-rite-products-corp/0446164281/8599533 The data sheet will give the exact attenuation curve. There is an oval button near the top to download the data sheet. Here is the data sheet. file:///C:/Users/19712/AppData/Local/Temp/446164281.pdf Vince

Look pretty legitimate. Decent margins on spurious emissions. You can see little amplitude modulation sidebands about 35KHz out. Not a problem at all. Just a curiosity. Vince

I agree with people who suggested it is probably common mode radiation from the coax or the whole radio. Put some big UHF ferrites on the coax & power cable and you'll probably see it go way down. Vince