marcspaz

I hate to say it, but sometimes a desired location just doesn't work, regardless of what you do. As an example, there is a repeater I like to talk on that is 35 miles from my VA home, in a North/North-West direction. Due to terrain and atmospheric behavior, if I have my antenna smack in the middle of my driveway, I can work the repeater all day with 1 watt, receive full-quiet, and generally have a great path. Well, if I move the exact same antenna, mast, tripod, etc., 2 feet in any direction, I can no longer hear the repeated and can't bring the repeater up, even with a full 50w. With the antenna mounted on my home's roof, I can hear that repeater and talk on it, but I get poor audio reports and the receive signal is so low that my s-meter doesn't move. It's starting to sound like you may be experiencing a similar issue. Especially because you said if you hold it at an angle in your hand and point it in the repeater's direction. It almost sounds like you are using a crude version troposcatter (oddly just discussing in another thread) to overcome whatever is blocking your signal path. It sounds like its just time to pick a new location.

There is a propagation method called troposcatter that you can use to intentionally talk 300+ mile on UHF, repeatedly and somewhat predictably. If you use high gain parabolic antennas on both ends and aim the beam at the horizon or just above, in the direction of the other target station, the signal scatters off of objects in the atmosphere. A small portion of that scattered signal gets refracted back to earth and heard by the receiving station. Because only a small amount gets refracted, the more power you use and the higherthe gain on the antennas, the higher the likelihood of success. While it does occur in the 450MHz to 500MHz space, the 2 GHz space yields the best success.

If you have a tap and die set, I would add more than the 3 radials to the VHF ground plain to improve performance and help ensure the filters are not overwhelmed. The more radials the better.

Wrong time of the year for traditional ducting... but we have a geomagnetic storm that is starting. It's going to peak in about 2 days and expected to last for a few days. Last time I was in Florida and this happened, I was able to talk from St. Pete to Panama City Beach for several hours a day several days in a row. During geomagnetic storms, more often than not, UHF radio waves get absorbed, causing reduced range. Other times UHF can get reflected like HF NVIS propagation. The easiest way to tell if that is happening now is if you have a GPS system that relies solely on SatComms (not cellular) and you are having accuracy issues or an outage. There are some websites that map this stuff out, too. Been a long time since I looked for them, though. EDIT: This tropo map is indicating that you may be right... how about that! https://www.dxinfocentre.com/tropo.html

Welcome! There is lots of good info here. If you have any questions and can't find the answers in existing threads, start a new one and we will do what we can to help. Have Fun!

This^^^^

It gets hard sometimes. Part of the reason I took a break was because I was sick of the arguments. Anyway, I sent the radio back to Midland last week for an alignment and to have the power turned up. Let's see how this goes. When I get it back, I'll retest the power output and blow the dust of the signal generator to test receive sensitivity.

100% agree. Great post.

I only have one problem with this video. He said it doesn't receive as well because it's a ROC. Not only that, he went on the say that every other type approved radio is better than the Midland, but did nothing to demonstrate that. I'm a little confused by this guy (and others I have seen) complaining about the Midland and others being a ROC instead of a superheterodyne. There are ROC systems that outperform some superheterodyne systems all day long and cost as much as $10,000 for amateur transceivers. Flex SDR is a great example. There are POS superheterodynes and POS ROCs. The style of tech shouldn't be automatically discounted as junk or awesome based on design style alone.

I know the SWR and watt meter may not agree with this statement, but I would try this anyway. Hook-up the Comet, put the tip (center lead) of the connector in the radio, but don't let any of the ground connection or collar touch the back of the radio. If it hears fine, you need to test your transmission line. I have experienced your symptoms many times over the years and found that there is a problem with the cable. Typically a full or partial short circuit in the connector during assembly, but also occasionally in the coax itself. If you have an ohm meter, look for a short between the coax center and ground both while connected to the antenna and on its own. Also see if you can find someone with an antenna and coax analyzer. That said, don't discount anything mbrun stated. That is all good info. I personally would start with testing the cable so you know you're not chasing a ghost while using his troubleshooting recommendations.

@axorlov I fully agree. My 40m mobile antenna is dead smack 1:1 in the center of my privileges, but its a giant coil system with an 86" whip. There is zero chance of the antenna being efficient even at 1:1. Given that it slides to 2:1 on the top and bottom of the spectrum doesn't bug me at all. Honestly, while not ideal, even under 3:1 is still workable.

Licensed by rule is the same as CB, correct? No physical license issued, cost or application? Just assumed by use?

G... most modern radios are pretty good at protection circuits. However, nothing is bullet proof and everything can potentially catch on fire. I have been involved in radios professionally and as a hobby for over 40 years. I lost count of the total number of radios and amps have literally caught on fire due to protective circuits failing when other stuff goes wrong. And it didn't matter if the equipment cost $50 or $100,000. Believe me, it can all burn.

QFT!

No, I actually needed it for a trip over the past weekend. I just shipped it out today. However, based on feedback from Midland as well as others, I expect it returned by 02/18. I will share the results as soon as I get the radio back.

If the antenna is higher than the roof line and at least a few feet away laterally, the roof should not have any impact. I will say that you may be getting a bit of a shadowing in the garage, reducing the amount of RF noise you are exposing the antenna too and mimicking filtering. I do this all the time in amateur radio on purpose. I will use a 7MHz antenna to listen to 3.8MHz signals, because there is much less noise due to not being at the resonant frequency I want to hear. Also, a higher gain antenna at a hire elevation is going to here more of everything, including noise. It is going to be almost impossible to diagnose over the internet, but I would confirm your VSWR is good and then start looking at filtering the signal with a band-pass filter.

I care about the losses with a meter on a 200w system. Especially with this 300' feed line running up my tower. Losing ~52w per dB of loss is a really big deal. I mean, who cares about only losing ~13w per dB on a 50w system. Especially when their mobile antenna cable is only 6 feet long. 52w per dB is way worse. See how silly that sounds? Just my own opinion... either you are going to be picky about losses and say " I want every last drop of power" or you're not. And dB loss from meter insertion is dB loss, not some arbitrary fixed wattage. I took a few minutes to measure the insertion loss from my meters. Its about 0.04dB per meter. On the 50w side, it totals 0.4w and on the 200w side it totals 1.6w. I kinda feel like 0.4w isn't a "make it or break it" amount of power loss on a 50w system.

So, one of the reasons I leave a meter inline actually came true yesterday, on my Ham gear. I was using my VHF radio with a 200w amp. I have a Watt/VSWR meter between the radio and the amp and another between the amp and the antenna. With no warning and with zero indication other than the meter, my output power on my amplifier shot up to well over 300w, running about 70% more power than designed. What likely happened is, there may be a cold/broken solder joint on a ground circuit for the final stage power regulator. Instead of nuking my amp and possibly having a fire at my desk by continuing to use the amp (because without the meters I wouldn't have known), the meters helped me catch the problem immediately. So now, instead of an $800 loss for the amp and potential untold damage to my home... I most likely will fix my amp for free. Sometime we are prioritizing the wrong potential losses.

Hey Phil! I didn't do any significant technical testing on the MXT500 beyond the peak power. I can grab a signal generator and test it when it gets back from Midland.

Same here. And the reality is if I really want to talk to someone and don't hear anyone, with only 8 high power channels, I can call for a contact on every channel in 2 minutes, and that's allowing 10 seconds or more per channel for someone to reply to me before I spin the dial. Like I said, I'm not against the users agreeing to standardize among themselves... but I'm not holding my breath. Especially since ORI died off, and the was the closest to "coordination" I have seen on this service.

It was... it was intended to establish the repeater travel channel and tone. But don't confuse people still somewhat honoring the ORI principles with "simplex" over the road use. Two distinctly different conversations.

Subbed

@WROZ250 I had to spend some time thinking about a response. Please don't take offense by my last post or this one. While I quoted you, it was really intended for both you and gortex, replying to the combined ideas. It was a little friendly ribbing with some significant truths.

I have to 100% disagree with almost all of this. LoL There is no rule, exception or most. There is only science and fact. The fact of the science is, this is a UHF line of sight service of which range is strictly limited to line of sight and RF interference or lack Thereof. When someone speaks in absolutes with words like "always" or "never", and someone provides and examples of how their statement is incorrect, it's somewhat disingenuous to move the goalpost by throwing the "exception" flag. What is the exception for someone who lives in the city is the norm for someone who lives in the mountains.

Same here. I was on Skyline Drive using a 5w HT and talked 82+ miles to a repeater in Woodbridge VA.