SvenMarbles
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Posts posted by SvenMarbles
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1 hour ago, WRXP381 said:
Wow. I have no answers and I’m really not trying to be a jerk but I’m so glad I simply put up my antenna and it works. This type of stuff would drive me nuts and right out of radios. I hate chasing junk like this. Good luck. I hope it works out.
Everything does still work fine. I'm just being a bit hyper-vigilant over my SWR numbers. I thought I had a pretty good grasp on "antenna-ry" tuning, and such, but this is just puzzling me.. I just kind of want to understand what is causing this.
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For about the last week I've been dealing with a sort of frustrating issue with my SWR numbers.
I've got a yagi antenna installed outside about 16 feet high that went up about a month ago. When it was newly acquired I spent the time with it on the ground connected to my nanoVNA nudging the tuning block back and forth to get a nicely centered low SWR in the GMRS ranges I desired. I tightened the set screws nice and firm to lock everything in, then spent the better part of an afternoon getting it erected on my mast. Ran everything with a nice LMR-400 type coax.
Everything stayed just about as desired until randomly one day I fired the radio up and noticed that my SWR reading (From my Surecom SW-102 that just sort of lives in-line) was reading about a 2.3 SWR.
Now a little bit more context might be necessary about how I operate this setup, and I apologize for this post getting a bit long winded. I have a sort of makeshift "tower" setup consisting of a 4x4 fence post concreted about a foot and a half into the ground, and then a few sections of masting pole (from the TV antenna aisle of the home improvement store) mounted onto it. At the top of that is actually a VHF antenna for MURS. My GMRS yagi is mounted further down on a PVC arrangement that the runs down parallel to the steel mast. This arrangement is set up so that I can grab the PVC that runs down and manually twist it to point the yagi in different directions. I'll include some pictures below.
So as stated before, I noticed that my SWR suddenly spiked one day, and my assumption was that my tuning block must have moved around. Now, I've got LMR-400 run up to this antenna, which is a bit of a thick and stiffer type coax. It's got a bit of a slacked loop at the top by the so-239 connection point on the yagi to accommodate the twisting movement of the yagi, but there's definitely a bit of torque being applied on that connection point due to the stiffness of the LMR-400. It's zip tied off a bit below to support the coax at that spot. So with that being said, my concern was that just the slightest bit of movement at the tuning location must've caused the antenna to go out of tune..
I then spent the better part of an afternoon bringing the pole down, fussing with the tuning block again with the whole pole arrangement laid down and propped up slightly. No matter what I did, my SWR's wouldnt budge from about 2. Suddenly a breeze came through and blew the yagi from it's propped up position, spinning it down and making contact with the ground. No big deal,.. I rotated it back up and again to be upright and not touching anything, and bingo, my SWRs were suddenly back down to where I was wanting them. At that point it occured to me that the way I have this yagi set up is completely electrically isolated up in the air (with it being on PVC). Wind had been blowing and putting a charge on the antenna, and when I brought it down and had the little mishap where the antenna touched the ground, it allowed the accumulated electrons to run off.. So that was the lightbulb moment. Everything is fine, I've just got to get some sort of grounded path in my line to this antenna..
My simplest way of doing that was more on the radio side. I took a length of wire to the middle screw on the power outlet at the desk and connected that to the grounding lug that's on the Surecom SW-102, which sort of remains permanently in-line of the radio setup, whether it's powered on or not, it maintains continuity as just a "connection point" like any adapter would.. I fire it up periodically just to see what things are doing. But this accomplished my goal of getting the circuit contacting my service ground.
So here's my only remaining issue. On the VNA, it shows an SWR of 1.68 across 467. but on the Surecom it reads 1.38 when keyed up. And it does so whether my grounded wire is connected to the Surecom meter or not... It also seems to move around a slight bit day by day. I've seen it get as low as 1.01, and then randomly another day it's 1.4..
Why am I getting these shifts in SWR, and why are the readings between my meters inconsistent? Anyone have any suggestions on what to look into?
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27 minutes ago, WRXP381 said:
In my opinion is the coax and antenna are waay more important than wattage. Line of sight and height is always a big factor. My 20w base unit does 234 miles into the Las Vegas repeater from my location in the Southern California desert and it comes in with great reports from net control in Las Vegas. Would 50watts matter? Might come in even better but no one has ever told me I need more. And no one is annoyed either.
That’s a good example. You’re probably at an optimal terrain position to be able to do that. You’re doing it with 20 watts.
lets suppose you were in a sub-optimal terrain position. The 50 watts wouldn’t fix it..
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37 minutes ago, OffRoaderX said:
50W is good, especially when you have a long-run of that leaky coax, to get more juice squirting from the antenna.
50W is also good to step on the other guy that is irritating everyone but only has 20W.. all else being equal.
Yes. That’s something I hadn’t considered. I could step on top of the strange random men who are also on channel if I wanted lol.
In my use case though, it’s just the wife son and whoever else I decide is a relative that day for GMRSing.
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9 minutes ago, back4more70 said:
The first thing that comes to my mind is that you can always dial the power down on a 50-watt radio, but once you hit the max on the 20-watt there is nowhere left to go.
That’s definitely true..
But here’s another enecdote. I once received an SSTV image from a cube-sat that transmitted at 1 watt.
The point being that if you’re in the clear,.. You’re in the clear.. 1 watt or a factor of 10 doesn’t matter..
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I’ve spent a fair bit of time modeling my own location with software, and also doing a lot of empirical testing out and about. Home to car, car to car,.. Changing variables, Height, antenna gain, and power.
GMRS is UHF,.. The properties of UHF are the following,.. Lossy as heck on coax, is line of sight, can punch through manmade structures better than VHF can, but ultimately crashes into terrain and dies.. Doesn’t matter if it’s 5 watts or 500. Nothing defeats the mound of dirt. You really have only one remedy. Height….. On both the transmitting and receiving side.
Power just really hasn’t ever been a substantial factor as far as variables go in anything I test or model from 15 watts to 50. Even 5 watts gets into the same places, just at a lower volume. But on UHF, the things that kill it seem to come into play well before the wattage difference between 15 watts and 50 does.
Is running your GMRS at 50 watts just a waste of electricity?
Tell me about why you might want to run a 50 watt radio over a 20 watt radio and not have to have such an amp draw…
- Knilc and kapoijerj334
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2 hours ago, WSAA635 said:
Here's the meter set up I'm using.
https://www.amazon.com/gp/aw/d/B08ZC7HS75?psc=1&ref=ppx_pop_mob_b_asin_title
I have the HAM version that's Bern unlocked. From what I understood all the radios are the same only the firmware changes depending on the setting(HAM, GMRS, Unlocked) so with it being unlocked it should give max power.
As far as doing the power tune, nope, not touching anything. I already bricked an H3 trying to do a firmware update, not going to risk the H8. I'll live with it just the way it is.
One thing that I did notice is that when doing those power tests with meters like that (and mine), what you have on the antenna side of the meter matters. Whether it be a dummy load, or a tuned antenna. I did a lot of work recently on my coax run and antenna setup. After doing that, my output readings increased.. It’s almost as though the radio feels like what you have going on down line of your coax is junky and it only puts out a lower percentage of power..
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If you bought the “GMRS version” of the radio. It’ll stay 5 watts even after unlocking.. You might have to use the “power tune tool” from the Tidradio website and increase the values…
It goes to 10 watts UHF and 12 on VHF. Trust me..
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12 minutes ago, WSAW350 said:
^^^^^^^^^
So it appears that Messi & Paoloni's Ultraflex 10 can out perform LMR400 coax in the loss department. And it looks to be $95 at Buy Two Way Radios for a 50' length. Thanks for posting the PDF.
I see it as nearly the same, maybe SLIGHTLY worse actually. But it has the added benefit of the more manageable cable...
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For GMRS, a 50ft run is what I'm comfortable with. It's at that point that I'd want to bring my radio nearer rather than run more coax.
Buy "KMR-400" from Amazon. MookieRF. Get the 50ft piece.
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On 2/4/2024 at 7:35 PM, Santiam said:
I really like my RT97..Works great for what I need, which is occasional use in the mountains for communications. I can get about a 30 mile circle which is more than enough for my needs.
Some people on here don't recognize that their particular situation doesn't extrapolate evenly over the country.. Yes, you would like to have your own repeater, and it looks like you do for your needs. nice work..
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I should mention too, it's happened very seldomly. Maybe 4 total times in the countless hours that this radio has been operating. It's really not a bother, but more of a curiosity.. I just haven't been able to make any sense of it..
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14 minutes ago, WRZE995 said:
My guess - you have an ANI-ID (PTT-ID on some other brands) set on the handheld,(menu item 39 of the H8, and then are receiving a transmission that is sending that ID as DTMF tones somehow (likely a setting configured to send the PTT-ID on start/end/both sides of the transmission)
P call is short for Priority Call and is triggered based on receipt of that ID. NOT the same, but sort of like MDC code function on a Motorola system.
That all makes perfect sense, but I never hear any DTMF going out when this happens. Thanks for clarifying what that ANI-ID stuff is though because I never knew really.
This will happen just sort of randomly when Ive got the radio on a repeater and chit chat is going on. It just happens sort of randomly..
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You can give your call in CW, and it's not your problem if anyone understands it...
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Is anyone else here running an H8 and randomly have the radio make a beeping tone and then display "P call" on the display? I see nothing in the manual that calls it out.
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I can’t remember if I read about it somewhere here in these forums or on a FB group post, but someone was mentioning about, for example, a 6db gain mobile antenna. The way that it accomplishes that gain is by shallowing down that take off angle into something more narrow of disc shaped and really concentrating that radiation to something like a degree or two. And that’s great for ERP increases, but a mound of solid dirt in front of you at the foot of an incline on the roadway is just going to absorb it if you’re running 5 watts or 50. And in this scenario, you’re just beaming that signal nearly horizontally right into it. So if there was a receiving vehicle a mile ahead and already on top of that increased elevation, he may not hear anything at all.
But now suppose you have a 3bd gain antenna which is a bit more Omni direction in the vertical axis, perhaps shooting as high as 10-15 degrees. It’s lower ERP, but would be casting signal into more useful directions in realistic terrain environments.
When you first get into mobile line of sight radio-ing, one of the first things that you become more keen on is how the terrain lays out ahead of you as you’re driving. You see those high points, and low dips and you just know when you’re optimal for shooting out a nice signal and when you’re likely to get into a dead spot down in a hole. So with that being said, is a high gain vertical actually counter productive in mobile applications?
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5 hours ago, bshort said:
There's d-bags on both sides of the spectrum. The gmrs putz that calls out like an old cb'r and the over-compensating ham. I've seen both about equally.
For sure, but,.. It's been my experience that it's gotten that way because of all of the hams putting the "ham flavor" all over the GMRS band.
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4 hours ago, marcspaz said:
I could be misreading the post, but I think OP called out to see if anyone needed help, not that OP needed help... I think. /shrug
So it was like,.. “Hey, anyone out there need any help?”,.. And 34 people responded on ham radio saying “Yes, I need some help over here!”..
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You yelled for help on the radio to see what you'd get back? lol Alright then..
I guess every area of the country might not resemble the rest, but I can tell you for sure that GMRS far more active where I am. There's still plenty of 440 and 2meter stuff, but all of those guys are just also on GMRS. Not sure why so many hams do that, but it seems to be a thing.. The GMRS repeaters out here get way more traffic than the club ham repeaters..
But as for what's a better SHTF radio. Technically anything that works to reach your intended party is a good one. I will say this though. GMRS is SUPPOSED to be more for the family units to be able to carry on with more "familiar talk" with husband/wife/kids etc. Somehow though I think if it got used that way hams on the channel might actually accuse you of being in the wrong place, and that you're interrupting the "rag chew".. The irony.. Ham radio on the other hand is explicitly hobby radio. You're not supposed to use it for practical or "familiar comms". You're just supposed to go on there and talk to other radio guys about radio stuff.
But I digress.. If i'm choosing the most appropriate line-of-sight band for what my idea of SHTF backup comms is, I'm choosing the one I get to have all of my people setup with, and not the one that is only supposed to be for hobby purposes.. Colostomy bag Larry ain't showing up with food and blankets for you..
- WashingtonMatt and RayP
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Do you think you can try to get more recordings of it, maybe for longer?
This sounds a lot like a data mode that isn't even in FM that's trying to be demodulated in FM.. If you do a lot of HF tuning, you'll know what I mean..
I wish i could be around for it and try to tune it on an RSP SDR.
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56 minutes ago, WSAG543 said:
Thanks for posting. I was just thinking about programming some MURS channels on my H8 GMRS running in unlocked mode. I mostly want to listen but it would be nice to know I could transmit if needed.
It gets 12 watts on MURS. I actually have a little circle of MURS guys out in my area so it's actually something that I'm on a fair bit. Even went as far as to get an actual 6db MURS purpose made antenna mounted outdoors. So I can definitely vouch for the H8 being suitable for MURS.
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Also, the good news is that it’s GMRS that we’re discussing here. No need to “dual band” anything.. We should enjoy the luxury of only needing to target one resonant frequency “chunk” and making the best of it…
For 462-467 the quarter wave, purpose cut for that specific frequency (shorter) would provide a better balanced dipole to the radio body…
Needing more FARS from a handheld
in Technical Discussion
Posted
It’s possible, if you’re willing to operate your HT as not an HT. Get an N9TAX slimjim antenna (GMRS version). Screw it on and sling it up someplace. It’ll hit your repeaters as long a those repeaters are worth a damn..