Microwave Guy

Planning to install an NMO mount on my truck roof for a Larsen 2/70B antenna. I've read conflicting information about the proper hole size - some say 3/4", others say 19/32". What's the correct drill bit size for a standard NMO mount? Also looking for advice on proper sealing techniques to prevent water intrusion. The truck will see daily use including car washes, so waterproofing is critical. Should I use butyl tape, marine sealant, or both?

pretty much just feel honestly, but theres some general logic to it. on a clear local repeater where the signal is full quieting, most people just rattle off their callsign without phonetics and thats totally fine, everybody hears it fine. but the moment theres any noise, flutter, QRM, or youre working someone far away, phonetics save you from having to repeat yourself three times. on HF SSB i basically always go phonetic for my callsign on the first transmission, especially if its a first contact or the band is noisy. its just habit at that point. the mid-QSO thing you mentioned, yeah dont overthink that. if someone asks for a repeat just drop into phonetics naturally, nobody cares. the whole point of the system is clarity, not some ceremony you have to perform perfectly.

ive had pretty similar experiences on 17 this week actually. caught a pile of JAs Sunday morning which i wasnt expecting and then the band just died hard around noon. i think 17m is one of those bands that rewards just leaving the radio on and checking back in rather than trying to predict exactly when itll open up, at least thats been my experience. i dont totally understand all the solar flux stuff either and ive been licensed for like 3 years now so dont feel bad. i mostly just watch the DX cluster and when i see spots coming in from somewhere interesting i run over to the radio and see if i can hear anything.

Vanity calls let you personalize your ham radio experience - I got one with my initials and it's been great for CW work. Much easier to send K1ABC than something like KF5XYZ! Takes about 18 days to process once you submit.

The Holy Cluster launched in late 2024 and plots live spots on an interactive map, making DX hunting more visual than traditional text clusters. Perfect for mobile use and has dark mode too. No software download needed, runs entirely in your browser.

dont overlook just cleaning the existing fan and making sure the vents arent clogged, mine was running way hotter than it should have been and turned out there was like 3 years of dust basically insulating the heatsink. embarassing fix but it worked lol

the neighbor thing is real and ive dealt with it too. one thing worth considering before you go down the big array path is that a single well-built long boom yagi like a 17 or 19 element on a decent az-el rotator is going to teach you a lot more about the mode than trying to phase four antennas together before you really understand whats going on. phasing harnesses and getting the polarization right and all that is its own whole project and if something is off you wont know if its the array or your setup or what. also dont overlook the importance of a good az-el system. tracking the moon accurately matters, people cheap out on that and then wonder why their signal is inconsistant. I use an old Yaesu G-5500 which isnt perfect but it does the job for a single antenna setup. you'll want to run something like Moon Sked or similar to track the lunar window and plan ahead since you only get maybe 10 hours of moon time per day depending on your latitude.

yeah what he said about the 4 contacts. also just wanted to say i was in the exact same spot like a year ago, was so paranoid about messing up the log or being outside the activation zone. turned out fine and honestly the chasers are super helpful, a lot of them will walk you through stuff on the air if youre new. some of them have been doing this for years and they can tell when its someones first time and they're patient about it. have fun up there

QRN drove me crazy for the longest time because i kept mixing it up with QRM. the way i finally remembered it was QRN = Nature (static from storms etc) and QRM = Man-made. probably not how youre supposed to remember it but it worked for me lol. also QRX means stand by or wait a minute, and QRT means im shutting down or going off the air. those two come up more than youd think

yeah what he said basically. i got tripped up on the same thing when i upgraded. the ARRL band plan is just kind of a gentlemans agreement about like where CW ops hang out vs where phone is, its not actually law. the FCC part is the legal stuff you have to follow. took me a while to get that straight in my head too honestly just go listen on 40m for a while before you transmit and youll get a feel for where things are happening. most of the SSB action is up around 7.150-7.250 during the day at least here in the midwest

this is making me realize our group probably needs to actually do one of these. we talk about being ready but ive never actually sat through a real structured exercise, just kind of assumed we'd figure it out if something happened. reading this not so sure anymore lol

There are two approaches for handling connectivity: Radio Only mode (checking "Radio only, local message hub" and "Forward messages via HF to another RMS") or Hybrid mode with simulated internet outage. I'm configuring our club's RMS Relay for emergency exercises and need to understand the practical differences in message handling delays. Configuration question: For a true internet-down scenario lasting 48+ hours, which approach provides more reliable message forwarding? Documentation emphasizes setting local message retention longer than exercise duration and enabling automatic operation. Currently running Windows 10 with RMS Relay 1.0.8.0, Pactor 3 on 40/80M.

Set your practice tool to 25-30 WPM to train your ear to recognize sound patterns, not individual dits and dahs. LCWO.net is completely free and offers multiple training tools with primitive but functional interfaces.

so ive been going back and forth on this for like three weeks now and i need to just pick something and build it. the situation is i have a decent sized backyard, maybe 80 feet wide, and im trying to decide between a simple 40m dipole fed with coax versus putting up a quarter wave vertical with a radial field. primary interest is ragchews and some casual dx when conditions cooperate, not contesting or anything serious. the dipole feels like the obvious choice because its just easier to build and i have the wire already. but ive read a bunch of stuff saying verticals are better for dx because of the low angle radiation and now im second guessing myself. neighbor on one side has a metal roof which im slightly worried about with the vertical but maybe thats a non issue i dont know. anyway not looking for a definitive answer just curious what people who have actually used both think in a typical suburban backyard situation. my coax run would be about 60 feet to the shack either way.

PSK31 and JS8Call both allow proper conversations if that's your style. PSK31 excels at weak signal work and ragchewing with its text-based keyboard communication. Try both and see what fits your operating style.

nice work getting it up and making contacts, that's really the proof right there. i did almost the exact same thing for my first real antenna build except i used 12 gauge and it was way heavier than i expected, the center insulator i made from a piece of cutting board was sagging like crazy haha. ended up having to add a rope support in the middle. anyway on the balun thing -- i just use a W2DU style choke made from a bunch of type 73 beads slid over the coax right at the feedpoint and it works great for 40 and 80. cheap and easy to make if you can find the beads. there's a guy on one of the homebrewing sites who has a calculator for how many beads you need for different bands

so ive been meaning to do this for like two years and after the storms we had last month kind of lit a fire under me. i picked up a used ft-891 a while back and thats going to be the main radio, and i have a decent little 40ah lifepo4 battery from bioenno that i use for portable ops already. got a pelican-style case from harbor freight (the apache ones, they work fine dont let anyone tell you otherwise) and i've been slowly throwing stuff in there. so far i have the radio, battery, a end-fed antenna kit i built, some coax, my license and a laminated card with local repeater freqs and the simplex calling channels for our region, some basic tools like small screwdrivers and crimpers, and a notebook and pens. oh and a headlamp because obviously. the problem is i keep second-guessing myself. like am i overthinking the antenna situation or is having just the one wire antenna kind of limiting. and i dont know if i should have a separate VHF/UHF HT in there just for local stuff or if i should count on my everyday HT that i carry. feels weird to have redundancy for redundancys sake but also thats kind of the whole point right what do you guys actually bring that ended up being useful when it mattered

yeah the inverted V is super forgiving honestly, the angle of the legs changes the feedpoint impedance a little so you usually end up somewhere between 50 and 75 ohms depending on how shallow the V is, which works out pretty well for coax without a balun. though i will say, if you didnt put a 1:1 choke or any kind of balun at the feedpoint you might be getting some RF coming back down the coax shield. doesnt always show up in the SWR but it can cause noise issues or weird patterns. worth throwing a few ferrite cores on the coax near the feedpoint if you have any around, takes about five minutes and can make a real difference. glad it worked out though, wire antennas are genuinely underrated.

so ive been licensed about 8 months now and just started getting into DX chasing which is way more addictive than i expected. my elmer mentioned DXwatch and i poked around on QRZ for a bit but honestly theres like 5 different ways to look at cluster spots and i cant figure out which one people actually use day to day right now i have the HRD logbook which has some kind of built in spot thing but it feels clunky and half the spots are already like 20 minutes old by the time i see them. someone at the club meeting mentioned DX4WIN but that felt like overkill for what im doing. i mostly just want to know when something interesting pops up on 17 or 12 meters without having to babysit a website all day is there an app that actually notifies you when a rare one shows up or do most people just have a cluster window open on a second monitor or something. also does QRZ cluster and DXwatch pull from the same network or are they different feeds entirely because some spots show up on one but not the other

seen this exact thing on a buddys 7300 last year. turned out to be one of the final transistors (RD100HHF1) had partially failed — not fully dead but limping along. what gave it away was the drain current was uneven between the two devices when measured individually. if you have a way to do RF power measurements on each side of the push-pull output you might find one is pulling more than the other. that said before you go digging into the finals its worth checking the PA bias voltage. there's an adjustment trimmer for it and sometimes they drift, especially if the radio has seen any heat stress. get into the service manual and find the bias adjustment procedure — its not hard and if the bias is low that would absolutely explain reduced output without any fault codes. try that first before assuming its a blown transistor because replacing those finals is doable but kind of a pain with all the thermal compound and torque specs.

That Icom teaser has me really curious. I've been running an IC-7300 for years and love it, but dual receivers in an SDR package sounds fantastic. Hope they announce more details at Friedrichshafen.

yeah the K index is gonna be your culprit more often than not when things go sideways like that. high solar flux is great and all but if you've got geomagnetic activity messing things up — K index 4 or above especially — the higher HF bands can just collapse, particularly on the paths that go over or near the poles. europe from north america unfortunately runs pretty close to the auroral zone so it takes the hit hard. what you want to ideally see is high solar flux AND a quiet K index, like K2 or below. when you get both of those lining up thats when 10m gets genuinely exciting. i worked something like 40 countries on 10m last november in a single weekend when conditions lined up just right. dipole at 30 feet is honestly fine for that kind of work when the band is really open, propagation does most of the heavy lifting. worth checking spaceweather.com or the DX maps site, they give you a good quick picture of whats actually happening. also look at the A index too, thats kind of a 24hr average of geomagnetic activity and gives you a better sense of whether things are settling down or getting worse

yeah the Q codes go way back to like the telegraph days so theres a ton of them but honestly in practice you only ever hear maybe a dozen or so on a regular basis. QSL just means confirmed or acknowledged, like yes i got your message. QRZ is asking whos calling, youll hear that a lot when someone is running a pileup and calling out for whoever just called them. QRM is interference from other stations, human made stuff, and QRN is the natural stuff like static from thunderstorms. QSB is fading, like the signal going up and down. QTH is your location. QRP means low power, under 5 watts usually. and yeah 73 is just like best regards or goodbye basically, its kind of the universal ham sign off. 88 means love and kisses, usually sent between operators who know each other well or sometimes from a male op to a female op but thats kinda old fashioned now i guess. honestly just keep listening and theyll start clicking into place pretty fast, took me maybe a couple weeks before i stopped having to think about them

yeah that gap between training and actual activation is real and i dont think theres a way to fully close it until you just do it. our group does tabletop exercises with the actual county EM staff now partly for that reason, so they get a feel for what we can and cant do before anything real happens. the phone patch thing comes up constantly, people assume ham radio is basically a telephone for emergencies and it takes a while to reset those expectations. the 214 thing is spot on too. i basically had to rebuild my logging habits after my first activation because i was used to casual net logging, not the kind of accountability a served agency actually needs. some guys in our group keep a pre-filled ICS form template on a clipboard so they're not scrambling. might be worth asking your EC if the group has anything like that for the next one. sounds like it went well overall though, first activation with real stakes is a good confidence builder once you get through it

check the ground on the radio itself too, not just the antenna side. ive seen installs where the chassis ground was fine at first but a loose connection would make contact intermittently while driving and it sounded exactly like what you're describing. scratchy and popping when theres vibration. just worth ruling out before you tear up all your coax routing