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G, what dictates polarization is size in wavelength and physical orientation. A full wave is omnidirectional.

Hey, G... Do you have a meter that can read 0.XX μV scale? I thought you told me you have an analyzer and the voltage was low. Is that correct? If so, what is the voltage reading going into the radio from the antenna transmission line, without the preamp? The filters help eliminate noise if you have poor selectivity, but the preamp is to help poor receive sensitivity or high line loss. Most good receivers will have a receive sensitivity of 12 dB SINAD on a signal that is 0.25 μV. Some are 12 dB at 0.20 μV or better. If the voltage on the antenna line (at the radio input) already meets or exceeds the radio requirements, the preamp won't do anything good. They are typically for signal loss due to high loss lines or signals filtered/trapped excessively. You may be better off with a 5/8 wave. Do some research on the antenna takeoff angles of specific antennas you are interested in. In the same way that high gain antennas are more narrow with regard to their usable frequency, some antennas tend to radiate up and out instead of down and out. Also, have you considered a vertical dipole? Or a loop? They are very easy and cheap to make... so you can experiment. Full wave loop antennas are true omnidirectional and fantastic with regard to receive sensitivity. I am about to build one for 80 meters after seeing a friend of mine a few miles away from me have full-quiet conversations with people I almost could hear at all.

Marc, I don't necessarily agree with everything you said here. But you have obviously put a lot of thought and study into it, and I respect that. And especially, thank you for the work you are doing in support of the Second Amendment!

Good Morning; Have you considered Alinco? They offer a Part 90 200 channel UHF mobile with 45 watt - 25 watt - 10 watt transmit, the DR-438 is UHF, the DR-138 is VHF http://www.alinco.com/Products/ham/mbl/DR-138HT/ http://www.alinco.com/Products/ham/mbl/DR-138HT/DR-138_438brochure.pdf Remtronix is the USA distributor for Alinco, I did need set-up support for my first h-t and they were great, both over the phone and via e-mail https://remtronix.com/land-mobile-radio/analog-radios/dr-438t/ The list price is $249.99, but shop around on the pricing Remtronix is selling it through Newegg: https://www.newegg.com/alinco-dr-438t-two-way-radio/p/16Y-0031-00004?Description=dr-438&cm_re=dr-438-_-9SIA5RC1W26967-_-Product Programming software and cable package: https://www.rtsystemsinc.com/DR-138-programming-software-and-USB-cable-s/2266.htm I almost purchased a new-in-package Midland mobile for $50.00 at a pawn shop last year (I don't remember which model) I passed on it and after reading all the posts here, I'm glad that I did I have not read any negatives about Alinco radios I have two different Alinco Part 90 h-t's, I intend to get a 3rd model h-t, and then I will probably buy the DR-438 and a ¼ wave NMO GMRS activity here around Clearwater, FL is starting to get off the ground, so I haven't gotten much use out of my radios yet, but I did use one of the h-t's on vacation in East TN in June, and I was told that it sounded really good, I'm going to stay with Alinco Just my two cents Merry Christmas and Happy New Year

Rugged Radios also misleads people to believe that as their customer, they can legally transmit on business band itinerant frequencies under RR's license. It's not a 100 percent lie*, but it is a gross misrepresentation. * A customer can do that at certain events where Rugged Radios is physically present and gives the customer express permission to transmit on the specific frequencies in use, but only at the event location and while the event is going on.

Nope, I don't think you do. I was talking about Midland.

You need to take on ECRs next: Expensive Chinese Radios. Still made in China, but repackaged with an American name and a price tag to rival that of a new Icom. I think everybody here knows what radio I'm talking about.

But it's important to realize when it's not practical to pay for more selectivity. Good commercial handhelds have enough selectivity to allow full-duplex operation by one operator, with a few feet of antenna separation. Good mobiles do better than that. If that's not enough desense protection, there's other issues at play. There's no improvement to be made if there isn't an issue, so it's just wasted money and/or lost functionality. CCRs work just fine as transceivers for 99% of the population. Yes, they don't work in the busy RF environments found at an enthusiast's base station, a command post, or when working near other operators on different in-band channels. They're cheap, show people what the hobby can offer, and include a lot of features (like FPP and ridiculous channel capacity) that new operators need to find their niche within the hobby and understand what parameters need to be configured to operate cleanly on someone else's system. And when they break (probably due to a novice operator blowing out the finals or dropping it), it's not a big investment being lost. They exist in the market for a reason: because they do work, unlike what the topic's title implies. They wouldn't sell if they didn't. It's important to understand their limitations, but they're not as severe as you're making it out to be.

Yes, I'd like to see how the tests were done. At best, it's demonstrating adjacent channel selectivity and receiver sensitivity. It's also generalizing all CCRs into the GD-77, which is quite reckless. So, we're trying to point out that these radios are junk, yet trusting the totally-not-copied-and-pasted selectivity measurements the manufacturer provided? Is repeater selectivity measured with cavity filters installed? If your noise floor is -50dBm you should be getting cooked alive. One odd point to mention is that a dBu to dBm conversion isn't as straightforward as it sounds since a lot of handheld radios (especially CCRs) don't present exactly 50 ohms at the antenna. I played around with a service monitor and found that my Connect Systems CS-580 had a receiver that was hotter than any of my commercial radios, and it also has a proper 12.5 kHz channel bandwidth for the narrowband setting (which doesn't really matter since I bet you're using it in wideband anyways). For a well designed receiver, selectivity is a compromise with sensitivity. You can add preselectors and tracking filters, but all of those add insertion loss, which contributes to noise figure. Most CCRs run nearly naked, so the frontend-on-a-chip is exposed behind only a LNA and probably some highpass filters. They can get very sensitive, but this leaves them prone to desense from signals not necessarily near the receiver's frequency. Either way, desense is more complicated than this graph can show.