Living in an old victorian mansion in the city:VHFUHF or HF HAM? (General class) - Page 1
Forum section: electronics / rf-microwave

author: Beamin
author_rank: Super Contributor
timestamp: November 11, 2020, 10:25:55 am
content: This is a bit of a repost from another thread where im looking to buy so gear but my question best fits here:I live on the 2nd floor of a old Victorian brick building. The elevation is in one of the higher parts of the city and to my south is the Chesapeake in baltimore; I have a general class lic that I got a while back and looking to get back into the hobby (Thank you bit coins for going from almost nothing to 15 grand the last few months! gave me a few hundred dollars spending money that should go to bills but Im going to treat myself instead ).So my two options:I really like Short wave SSB but I dont know how well that would work in a city trying to get weak signals. I have access to a fire escape so I could run a wire antenna from the second floor to the fourth story roof. Unfortunately it will be in close proximity to a metal fire ladder and brick and wont be anything complex. I found this type of brick really blocks RF signals; using a beofung 2m with a rubber ducky is pretty much useless inside. Even FM broadcast is tricky. Thats my 1st consideration to get a used mobile or base unit. I dont know how good a magnetic coil antenna would work out on the balcony.The 2nd option is to get a VHF UHF 2M 1.25M or 70 CM mobile or base station. Ill build the power supply or use one a generous member on this site (whos name escapes me, sorry) sent me a server power supply to power it. The antenna would probably be an omni directional with coax running to the 4th floor balcony mounted on the fire escape railing. Im not sure if I should use a spark plug lightning arrester, lots of metal around. I was thinking dipole but have no idea which way to aim it since im pretty much in the center of the city with maby a 45' path of open ocean that would be useless to point at.Does anyone else here have a HAM rig and live in the city? I tried to play with the local repeaters with the beaifung but those menu systems are useless; about as easy to use as learning mandarin, who puts squelch in a hard to get granular menu instead of a hard to use knob? Plus you cant program two of them without crashing your OS. Thats what you get for 40$. They are basically toys time for a real rig.ThanksBeamin

author: HB9EVI
author_rank: Frequent Contributor
timestamp: November 11, 2020, 10:41:14 am
content: hard to recommend somethingon VHF/UHF with FM only will be a fruitless occupation; SSB is certainly more interesting but its activities focus on contests mostly while the bands idle otherwise most of the time.also SSB on VHF/UHF is running in horizontal polarization; you're going to lose 20dB when operating with a common vertical omnidirectional. It's not impossible working like that, but it's far away from being effective.on the other hand on HF almost always something 'works' and even with limited antennas it's possible to get RF in the air (it's almost impossible to not radiate anything).certainly in city environment you have to count with a higher level of man made noise, something what can screw you up all efforts. It could make sense to work with a dedicated active rx-only antenna, which can placed out of the domestic noise and run the tx-antenna where ever it's possible to place it

author: Beamin
author_rank: Super Contributor
timestamp: November 11, 2020, 01:04:41 pm
content: Quote from: HB9EVI on November 11, 2020, 10:41:14 amI was thinking vert polarization for the vhfuhf; folded j or whip antenna with radiators since there is nothing to aim a dipole at; if I aim north I lose 3/4 of the area same with e and w. Pointing a dipole straight up doesnt work at all I tried. I was thinking take off the passive radiators and just mount the oval shaped direct fed element and putting it up high for a oval omni-directional, but I really dont like walking on the rusty old ladder several stories off the ground. I was going to do an antenna set up like you see on a police station or utility company where they have vert pol and 360' coverage that way I can cover the city, county, and across the bay. The SSB idea was only for the HF om SW not VHFUHF, I never heard ssb on the single meter bands. Seems like im not in a good area for SW although I could string a 4 story tall wire but that might just pick up a lot of noise.If I get the vhfuhf route what kind of SWR meter would I need and how many watts is enough? I noticed with HF if you dont have a few hundred watts youre not going to be heard, but on the other hand the 8 or so watts the VHF beofung puts out even in the country really doesnt go that far. The smallest hill and your signal is blocked even on 2 meters. I would like to cover at least 30 miles or have a hand full of repeaters to pick up. So far I would need:12v Power supply with some descent amps50' of 50 ohm cableF connectorsSWR meterAntennaGrounding wire (What do you ground to without dirt for a ground rod? Metal pipes off the building fire escape?)Radio w/ micWhat do you mean by separate rx and tx antenna? Would you need to build a PIN diode switching circuit? Or is this just for the HF option?The more I read up on this the more Im thinking uhfvhf plus its cheaper too.Do you live in a city?

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: November 13, 2020, 11:32:23 pm
content: Quote from: Beamin on November 11, 2020, 01:04:41 pmI wouldn't agree with this. HF SSB contacts are quite easy with 5w out to about 1000km and even up to about 3000km when conditions are good. CW and digital modes can also do well.It's not a QSO mode but milliwatts of WSPR can get out a long way. JS8 is quieter but is an efficient conversational mode with QRP.Some examples of what QRP can do are here:https://vk3ye.com/qrp/possible.htmHints here could be handy:https://vk3ye.com/gateway/foundation.htmIn the next few years we'll be out of the current solar slump, with conditions already improving. And no matter the state of the solar cycle 28 & 50 MHz SSB can be lots of fun with 5w.This presentation discusses what you can do with 5w.Here's some on-air examples.If you can get out and about (difficult in some areas at the moment) you can have results like this:

author: Beamin
author_rank: Super Contributor
timestamp: November 14, 2020, 12:31:49 am
content: Quote from: vk3yedotcom on November 13, 2020, 11:32:23 pmYou are actually one of my favorite posters here and love your channel. You inspired me to buy a bitX 40 meter ran a longwire ant with it got great reception but never made any contacts with it. I got frustrated with it and stopped using it. My antenna was pretty good going between the roof of the house and a tree had a balaun proper ground and everything and was well off the ground and out in the country with low noise, but no QRP or even local.So Im going to try UHF/VHF now. I really respect your opinion and love your channell so what would you recommend? I am willing to spend the extra money to buy a Japanese one.Another factor is I cant use a huge antenna; 2m is the biggest I can get away with. The japanese radios are right in my price range at around = or < 500$USD. What would you go with in my situation in your infinite wisdom?

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: November 14, 2020, 01:01:50 am
content: Quote from: Beamin on November 14, 2020, 12:31:49 amI'd troubleshoot the BitX. Maybe there's something wrong with its transmit audio or the output power isn't as much as it should be? And you'd need a good coupler if you're using an end-fed longwire antenna. It is possible for a mismatched antenna to receive well but be poor on transmit.Then there's operating and calling technique and timing. Really important. You won't get contacts with everyone you call but should be able to get a lot. Videos on getting contacts here:https://vk3ye.com/gateway/foundation.htmAs for antennas, assuming your longest length you can accommodate is 2m, that length could fit a 1.8m helical mobile whip for 28 MHz or a 1/4 wavelength vertical for 50 MHz. The latter can also work on 2m FM as a 5/8 wavelength vertical for FM contacts. For SSB a small 4 element beam can work quite well and looks like a TV antenna. A good combination for small spaces could thus be a small horizontally polarised beam for 2m SSB, a 5/8 wave vertical for 2m FM and 6m and maybe a thin wire dipole or mobile vertical for 10m. An indoor magnetic loop is a possibility for frequencies as low as 7 MHz.Re transceiver an FT818 would be good, giving all bands with the flexibility of HF for any portable stuff you might want to do. Other rigs are higher power but may be FM only.

author: A.Z.
author_rank: Super Contributor
timestamp: November 14, 2020, 08:49:24 am
content: given that you have access all the way up to the roof, did you consider running some coax from your apartment up there and setting up (e.g.) an HF multiband vertical antenna ?Also, given that you are in an RF "noisy" environment, you may consider putting up separate TX/RX antennas, in such a case, you may evaluate the idea of running up the roof a run of coax together with a run of CAT5 cable, the latter would allow you to control a remote relay box to switch antennas, those may then be a vertical for TRX and an RX only loop; the CAT5 could then also allow controlling a small rotator to aim the loopeditjust to give you an ideahttps://www.diamondantenna.net/cp5h.htmlhttps://www.wellbrook.uk.com/loopantennas/ALA1530LNby the way there are a lot others, the above are just to give you an idea of the kind of setup I described