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DrakeriderCa
Feb 3, 2005

But I'm a real cowboy!

Enilev posted:

The Baofeng will work on FRS frequencies, but it's illegal to use it on them. Among other things, FRS radios are limited to 0.5 W, GMRS radios (most are dual FRS/GMRS) are limited to 5 W, and neither can have detachable antennas. Will you get caught? Probably not, but who knows if the FCC will start cracking down in the future. Right now, the FCC doesn't even care that there's something like 10 times as many dual FRS/GMRS radios sold as GMRS licenses, but things can change.

How far away are your friends and family? If they're nearby, like within 5 miles, then handheld units like the Baofeng will work okay in simplex mode. If they're farther, like within 20 miles, you'd have to talk to them one of your local repeaters. It's not so much the power of the units as the curvature of the earth, so repeaters are built higher up to cover more area. Again, the Baofeng will hit those fine (though in an actual emergency, you'll probably be discouraged from using the repeaters for non-emergency traffic). If they're in another state, then you'd need an HF setup, which the BaoFeng can't do at all.

They'd be within 20-25mi or so. Terrain here is extremely flat. From the tops of our houses, we'd be almost line of sight. Is there a reasonably priced antenna that would make that possible with the Baofeng? Or would we be stuck relying on repeaters?

We'd probably also use them on camping/biking/hiking trips as a high-powered alternative to FRS. I didn't realize that using them on FRS frequencies was illegal, so I'll skip that.

Edit: Page 100 :smug:

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Enilev
Jun 11, 2001

Domesticated

DrakeriderCa posted:

They'd be within 20-25mi or so. Terrain here is extremely flat. From the tops of our houses, we'd be almost line of sight. Is there a reasonably priced antenna that would make that possible with the Baofeng? Or would we be stuck relying on repeaters?

A quick calculation says that you'd need both antennae to be about 60 ft off of the ground to overcome the earth's curvature. The cost of getting the antenna that high will probably outweigh the cost a high high-gain directional antenna.

DrakeriderCa
Feb 3, 2005

But I'm a real cowboy!

Enilev posted:

A quick calculation says that you'd need both antennae to be about 60 ft off of the ground to overcome the earth's curvature. The cost of getting the antenna that high will probably outweigh the cost a high high-gain directional antenna.

Ouch. Yeah, that isn't happening. So without building or buying elaborate base stations, we're stuck with repeaters?

Edit: What about a mobile unit that's pushing out 75w or so? Would that make any difference or am I still limited by the stupid earth's curvature?

DrakeriderCa fucked around with this message at 06:27 on Oct 7, 2013

Pham Nuwen
Oct 30, 2010



DrakeriderCa posted:

Ouch. Yeah, that isn't happening. So without building or buying elaborate base stations, we're stuck with repeaters?

Edit: What about a mobile unit that's pushing out 75w or so? Would that make any difference or am I still limited by the stupid earth's curvature?

I've done something like 60 miles over a range of hills to a 2m repeater in northern Sacramento. Similarly past several ranges of hills and a big mountain to another repeater near Vacaville. These were both at (IIRC) 10 watts on a mobile unit, set up in my 2nd story apartment with a 1/4 wavelength antenna on the balcony.

Is there a repeater near you? If there's one close-ish to everyone, it's probably a pretty good idea. The repeater should have a good antenna high in the air, and it'll repeat your signal at a higher strength and, again, at a higher power.

DrakeriderCa
Feb 3, 2005

But I'm a real cowboy!

Pham Nuwen posted:

I've done something like 60 miles over a range of hills to a 2m repeater in northern Sacramento. Similarly past several ranges of hills and a big mountain to another repeater near Vacaville. These were both at (IIRC) 10 watts on a mobile unit, set up in my 2nd story apartment with a 1/4 wavelength antenna on the balcony.

Is there a repeater near you? If there's one close-ish to everyone, it's probably a pretty good idea. The repeater should have a good antenna high in the air, and it'll repeat your signal at a higher strength and, again, at a higher power.

There are a few, from what I can see. I just don't want to tie one up in the event of an emergency, so I was hoping I'd be able to do it simplex. I'm sure these are questions that I would have figured out as I do the study and take the tests, but I appreciate the quick answers. We're kind of looking into this to see if it'll meet our needs in case we ever needed something like this.

Pham Nuwen
Oct 30, 2010



DrakeriderCa posted:

There are a few, from what I can see. I just don't want to tie one up in the event of an emergency, so I was hoping I'd be able to do it simplex. I'm sure these are questions that I would have figured out as I do the study and take the tests, but I appreciate the quick answers. We're kind of looking into this to see if it'll meet our needs in case we ever needed something like this.

Well, if you can handle random old guys listening to your family communications, repeaters are probably a good bet for range and usefulness.

You'll need to make sure your use doesn't conflict with the regulations for ham radio i.e. if you plan to coordinate farm work that might be a problem.

In other news, heard a guy on the local repeater mention his Hoveround, which made me grin and think of this thread.

Edit: 99% of the time the repeater is sitting idle so I wouldn't worry too much about tying it up. If there's some sort of general emergency, having everyone tuned to a repeater means you'll be in contact with other hams in the area too which is a bonus in general. If it's a family emergency, release your inner CBer and say "break" if someone else is using the repeater... They should clear the frequency for your emergency traffic.

Pham Nuwen fucked around with this message at 07:54 on Oct 7, 2013

eddiewalker
Apr 28, 2004

Arrrr ye landlubber
Is a little scanner chat all right? Everything in my county has gone p25, so my ham dual-banders are useless for public service listening.

Any p25 scanners worth buying? They're all stupid expensive.

Some reviews make or sound like extra software and data subscriptions are essential. How true is that? On a long drive, would I need to program in the whole route to hear anything besides plain small town analog?

How do proximity scanning features like CloseCall work? How close do you need to be?

Dijkstra
May 21, 2002

eddiewalker posted:

Is a little scanner chat all right? Everything in my county has gone p25, so my ham dual-banders are useless for public service listening.

Any p25 scanners worth buying? They're all stupid expensive.

Some reviews make or sound like extra software and data subscriptions are essential. How true is that? On a long drive, would I need to program in the whole route to hear anything besides plain small town analog?

How do proximity scanning features like CloseCall work? How close do you need to be?

Well, the best value in P25 scanners now is probably one of the Radio Shack models, (PRO-197 or the portable PRO-106) which are just GRE-made clones of the popular GRE models (600 and 500 I think). You can get them at your local RadioShack store or at scannermaster.com.

GRE has gone out of business, and are not currently manufacturing scanners, so all that's left of those is the current inventory.

Uniden is another story, they are still making P25 scanners but they cost a little more. I'm not really familiar with Unidens.

Programming any type of P25 or Motorola Trunked system more or less requires software. It can be technically done from the keypad but it's a huge pain in the rear end and will take you hours.

On a long drive you'll have to either program your route in advance or maybe use something like the Uniden Home Patrol which works off your zip code I think.

It's also worth noting that there are two phases of P25 systems. Phase one is probably what you're thinking of, and requires any digital-capable scanner. Phase two is TDMA and is being installed in a handful of places. This requires a GRE PSR-800 to decode (which of course is no longer manufactured.)

Your best bet is to figure out what systems are being used around where you live and buy accordingly. Chances are everything is Phase 1 and the Radio Shacks or Unidens will decode everything. However if you live somewhere there is a Phase 2 system you will have to hunt down a PSR-800 on ebay or something to listen to it. Radioreference.com is where you want to go to figure all this out.

I live in the sticks so I never use Close call, but it will only tell you what frequencies are being used locally, it won't automatically program a p25 system or anything.

eddiewalker
Apr 28, 2004

Arrrr ye landlubber
I was mostly wondering if CloseCall worked in a physical range of like, a frequency counter, or a quarter mile or what.

I work at entertainment events, so being able to "close call" wireless mics would be cool, though no general receiver I've ever owned has had wide enough RX filters for mics and such.

Sounds like its still a good idea to wait for a do-it-all public service scanner if I ever want firmware updates. Would you agree?

Dijkstra
May 21, 2002

eddiewalker posted:

I was mostly wondering if CloseCall worked in a physical range of like, a frequency counter, or a quarter mile or what.

I work at entertainment events, so being able to "close call" wireless mics would be cool, though no general receiver I've ever owned has had wide enough RX filters for mics and such.

Sounds like its still a good idea to wait for a do-it-all public service scanner if I ever want firmware updates. Would you agree?
Yeah, close call will work at events if they are using normal analog FM or whatever.

While GRE is out of business, GRE America is still in business, and continuing to provide firmware support for it's scanners. So if you do run across a GRE model it's fairly safe to buy one. Yeah I know it doesn't make sense but GRE and GRE America are two companies. One manufactured scanners and the other wrote software and functioned as a distributor.

Also, the Whistler group (of radar detector fame) has come to an agreement with Radio Shack to manufacture and support their current GRE manufactured and future scanners. They also bought all of GRE's assets. This is speculation but it's probably a matter of time before they start cranking out Phase II scanners. GRE was developing a rumored PSR-900 when they went under so it's possible that Whistler will release it before too long.

Uniden doesn't make a Phase II scanner but they will probably have to follow suit soon unless they want Whistler to have all the future market share.

So you could probably wait a little bit to buy and be okay if you want a phase II scanner. But if you are sure you only want a phase I then it's probably fine to go ahead and buy one as well.

wolrah
May 8, 2006
what?

AstroZamboni posted:

I just got a good USB mic and set up echolink on my PC, so if there are any goons who want to shoot the poo poo on the air, I'm KF7JKA and I'm on node 616843. Might be hopping on some repeaters here in a bit.

I just fired EchoLink up for the first time in a while. KD8JQS #411670. I think some of my local repeaters are on EL, but I need to look that up again.

SoundMonkey
Apr 22, 2006

I just push buttons.


eddiewalker posted:

I was mostly wondering if CloseCall worked in a physical range of like, a frequency counter, or a quarter mile or what.

I work at entertainment events, so being able to "close call" wireless mics would be cool, though no general receiver I've ever owned has had wide enough RX filters for mics and such.

Wireless mics also do a bunch of in-band signalling that's filtered out by the receiver (the transmitter reporting its battery level, pilot tone, mute switch status, etc), so what you heard wouldn't be all that great anyways. Listening with my SDR (so arbitrarily wide filter), it still sounds like rear end (this is with the mic maybe two feet away from the antenna.)

AstroZamboni
Mar 8, 2007

Smoothing the Ice on Europa since 1997!

wolrah posted:

I just fired EchoLink up for the first time in a while. KD8JQS #411670. I think some of my local repeaters are on EL, but I need to look that up again.

I opened hailing frequencies but you didn't answer. So it goes.

wolrah
May 8, 2006
what?

AstroZamboni posted:

I opened hailing frequencies but you didn't answer. So it goes.

I was on a call with my boss, heard you connect but didn't get back to the PC in time.

AstroZamboni
Mar 8, 2007

Smoothing the Ice on Europa since 1997!
Well gently caress. Now I'm cooking dinner.

wolrah
May 8, 2006
what?

AstroZamboni posted:

Well gently caress. Now I'm cooking dinner.

As I will be soon as well, I'm sure, but I lurk #hamradio and have my Quassel setup on a variety of screens around my apartment so you can get my attention there if I'm not around.

edit: Found my hometown repeater is on EL now and has a scheduled net coming up in a few minutes, time to see if it actually works.

edit2: And they're reminding me why my gear found its way in to storage. Someone as I type this is literally giving a weather report (hint: nothing interesting) to start off his "what are you up to" slot on the net. I'm still listening out of hope that some more normal seeming people check in, but it's greybeards_with_ailments.wav right now.

wolrah fucked around with this message at 00:55 on Oct 8, 2013

eddiewalker
Apr 28, 2004

Arrrr ye landlubber

SoundMonkey posted:

Wireless mics also do a bunch of in-band signalling that's filtered out by the receiver (the transmitter reporting its battery level, pilot tone, mute switch status, etc), so what you heard wouldn't be all that great anyways. Listening with my SDR (so arbitrarily wide filter), it still sounds like rear end (this is with the mic maybe two feet away from the antenna.)

Most of what I want to hear are Lectro IFBs, so there's no data to worry about.

SoundMonkey
Apr 22, 2006

I just push buttons.


So, question for people nerdier than me:

I volunteer at a local community radio station, and poo poo was a mess when I started, but I convinced them to buy both a new antenna (the old one was, no poo poo, a badly-mismatched mag-mount CB antenna ziptied to the mast with taped-together feedline of varying impedances). After some loving around getting the right adapters, we finally managed to get the new antenna up last week (with greatly improved range, of course). Something's a bit weird though.

For all these cases, the transmitter was set to 12 watts.

For shits, I hooked up the SWR meter with the old antenna, and it was showing a power output of about 3 watts, with a reflected power of... I don't know, because it pinned the needle on reflected power, which went up to 5W on that scale, so I'm going with "most of it".

Obviously I wanted to give it a shot with the new antenna to see how much better it was (lots). Transmitter set to 12W, SWR meter reports 6W output, with 0.3-0.4 reflected. Not horrible considering the condition of the cable. However, with the SWR meter in the line, the transmitter itself was reporting 6 watts of output with no reflection. Remove the SWR meter, and the transmitter is once again reporting 12W with about 0.1W reflected.

My buddy's theory is that the transmitter has been eating so goddamn much reflected power for literally years that it's completely unable to determine its own output power, which sounds reasonable (especially since the power knob was at about 75% for 12W, and it's a 30W transmitter). Is this the likely case, or is something weird going on, or am I just missing some basic principle of radio theory?

iostream.h
Mar 14, 2006
I want your happy place to slap you as it flies by.

Never trust power meters built into radios.
Get a separate unit to check the output with, doesn't hurt to compare it to the built-in one, but I'd only use that for informative purposes, not anything I'd rely on.

SoundMonkey
Apr 22, 2006

I just push buttons.


iostream.h posted:

Never trust power meters built into radios.
Get a separate unit to check the output with, doesn't hurt to compare it to the built-in one, but I'd only use that for informative purposes, not anything I'd rely on.

Yeah I wasn't trusting it too hard to begin with, since with 12W we should have been getting like four times the range we were, even with a bullshit antenna.

So basically, the 6 watts I saw on the SWR meter is what I should be believing? With a hundred-foot feedline of (gently caress I don't know the exact cable type, 50 ohm bit-more-than-1/2" thick coax of some kind, N connectors), accounting for losses there, is it possible to even ballpark the actual radiated power at the antenna?

EDIT: Also bear in mind said cable was adapted to BNC about four feet from the antenna, taped up to poo poo and back with electrical tape, then run via 75-ohm cable to the magmount antenna, so at the very least we now have an actual broadcast FM antenna (albeit a $30 sleeved dipole), and the feedline actually runs directly to the antenna (via one adapter).

SoundMonkey fucked around with this message at 01:58 on Oct 8, 2013

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

EDIT: Also bear in mind said cable was adapted to BNC about four feet from the antenna, taped up to poo poo and back with electrical tape, then run via 75-ohm cable to the magmount antenna, so at the very least we now have an actual broadcast FM antenna (albeit a $30 sleeved dipole), and the feedline actually runs directly to the antenna (via one adapter).

Well, poo poo.....where in this mess were you measuring SWR? That would seem to make a huge difference.

SoundMonkey
Apr 22, 2006

I just push buttons.


Motronic posted:

Well, poo poo.....where in this mess were you measuring SWR? That would seem to make a huge difference.

Between the transmitter and the feedline, because I'll be hosed if I'm climbing the mast.

EDIT: As in transmitter -> 4 feet of brand new coax -> SWR meter -> antenna feedline.

EDIT AGAIN: The bit about mismatched cables and poo poo was the PREVIOUS setup, now it's just transmitter -> hundred feet of coax -> antenna. Note the continuing lack of "lightning protection of any kind" in that setup.

SoundMonkey fucked around with this message at 02:07 on Oct 8, 2013

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

Between the transmitter and the feedline, because I'll be hosed if I'm climbing the mast.

EDIT: As in transmitter -> 4 feet of brand new coax -> SWR meter -> antenna feedline.

So you measured SWR across a bunch of hack jobs and now there is....

SoundMonkey posted:

just transmitter -> hundred feet of coax -> antenna. Note the continuing lack of "lightning protection of any kind" in that setup.

Your previous measurement is pretty much meaningless. Sure, you very well may still have an issue, but no one has any idea if you do or how bad it is at this point.

Lightning protection (properly installed) has nothing to do with this. Obviously it SHOULD be there, but if it makes any significant difference in SWR it's been done wrong.

SoundMonkey
Apr 22, 2006

I just push buttons.


Motronic posted:

So you measured SWR across a bunch of hack jobs and now there is....

Your previous measurement is pretty much meaningless. Sure, you very well may still have an issue, but no one has any idea if you do or how bad it is at this point.

Sorry, I was hugely unclear about this, the reading I took with the hackjob setup was for comedy purposes only, to settle a bet as to whether it would ACTUALLY go off the scale.

My basic question is "should I just go with whatever power output the SWR meter tells me and ignore the retarded transmitter."

EDIT: And yeah obviously lightning protection has nothing to do with it, it's just something else I have to deal with eventually. I'd certainly be open to anyone's suggestions as to how I'd implement that, though.

SoundMonkey fucked around with this message at 03:28 on Oct 8, 2013

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

My basic question is "should I just go with whatever power output the SWR meter tells me and ignore the retarded transmitter."

Well, that comes down to what you trust more. If this is a high dollar transmitter that should have a proper SWR meter built in and you are using some POS in line 30 year old MFJ.....yeah, probably believe the transmitter.

But really....you can get a new antenna analyzer for less than $300. And likely find someone who owns one to run it for you for free. There is no reason to guess.

SoundMonkey
Apr 22, 2006

I just push buttons.


Motronic posted:

Well, that comes down to what you trust more. If this is a high dollar transmitter that should have a proper SWR meter built in and you are using some POS in line 30 year old MFJ.....yeah, probably believe the transmitter.

But really....you can get a new antenna analyzer for less than $300. And likely find someone who owns one to run it for you for free. There is no reason to guess.

The SWR meter is brand new, the transmitter is of questionable origin and has been cooking its output stage for 3 or 4 years as a result of that hackjob. At least the SWR meter reads consistently and its readings make sense, so I guess I'll just go with that.

I'll try the local greybeards again but there's only like 3 or 4, goddamn small towns.

FuzzyBuddha
Dec 7, 2003

Quick question - I need to renew my license, but I'm in the US and the FCC is essentially shut down. What happens if it doesn't reopen before the expiration? My license expires next week. :(

Edit - S'pose I should have checked the ARRL website before posting. :)

quote:

Radio amateurs whose licenses expire between October 1 and the day after normal FCC operations resume may continue to operate until then, even if they have not yet filed a renewal application. Pending an official FCC announcement that states otherwise, applicants should apply for renewal no later than one day after the FCC reopens, if they want to continue to operate.

http://www.arrl.org/news/the-fcc-shutdown-at-a-glance

FuzzyBuddha fucked around with this message at 00:33 on Oct 10, 2013

Vir
Dec 14, 2007

Does it tickle when your Body Thetans flap their wings, eh Beatrice?

SoundMonkey posted:

I'd certainly be open to anyone's suggestions as to how I'd implement that, though.
Chapter 4 and 5 of Motorola's R56 Standards and Guidelines for Communications sites is one good resource for this, from an applied engineering standpoint. The standard covers everything from safety grounding to lightning protection and ESD protection, and contains some examples of both ideal solutions and solutions that can be retrofitted to existing installations.

I'd say at minimum your antenna coax should be connected to the building's earth rods/ring ground/structural steel at the point of entering the building. Ideally, you should also have a lightning protection device (like from Polyphaser) mounted at the entry point. There's not much point of having such a device if the first step of grounding the coax shield hasn't been done.

If it's a steel mast on a steel framed building, then your tower might already be grounded through the structural steel of the building, so you might not need to get any copper wire, just a couple of ground kits and maybe a Polyphaser. If it's a wood mast on top of a wood building, then it'll be a more complicated job. Could you make a little drawing of the building and antenna system?

Obviously your local electrical codes have to be obeyed as well. This typically demands that antenna coax is connected to the common house ground. If doing this connection affects reception/transmission, it is a symptom of the antenna system, radials and counterpoise needing improvement. This, as well as their ailments, is often the excuse greybeards have for not having any grounding and lightning protection in their stations. "It don't work good if I ground it."

If you use the antenna for reception too, or want to give extra protection for the radio, you might also want to connect a high-value resistor or coil between the coax and center to bleed off static.

SoundMonkey
Apr 22, 2006

I just push buttons.


Vir posted:

Chapter 4 and 5 of Motorola's R56 Standards and Guidelines for Communications sites is one good resource for this, from an applied engineering standpoint. The standard covers everything from safety grounding to lightning protection and ESD protection, and contains some examples of both ideal solutions and solutions that can be retrofitted to existing installations.

I'd say at minimum your antenna coax should be connected to the building's earth rods/ring ground/structural steel at the point of entering the building. Ideally, you should also have a lightning protection device (like from Polyphaser) mounted at the entry point. There's not much point of having such a device if the first step of grounding the coax shield hasn't been done.

If it's a steel mast on a steel framed building, then your tower might already be grounded through the structural steel of the building, so you might not need to get any copper wire, just a couple of ground kits and maybe a Polyphaser. If it's a wood mast on top of a wood building, then it'll be a more complicated job. Could you make a little drawing of the building and antenna system?

Obviously your local electrical codes have to be obeyed as well. This typically demands that antenna coax is connected to the common house ground. If doing this connection affects reception/transmission, it is a symptom of the antenna system, radials and counterpoise needing improvement. This, as well as their ailments, is often the excuse greybeards have for not having any grounding and lightning protection in their stations. "It don't work good if I ground it."

If you use the antenna for reception too, or want to give extra protection for the radio, you might also want to connect a high-value resistor or coil between the coax and center to bleed off static.

The antenna isn't used for reception, ever.

I'll take a look at that reading you mentioned. The thing is that our feedline doesn't really HAVE an 'entry point' - it's just run straight from the transmitter, taped to the wall, out an open window and up through the middle of the mast directly to the antenna. There's no proper grounding to speak of (we don't even have access to the electrical panel to make sure the transmitter is on the same ground as the mixer, much less actually have some fancy poo poo like a grounding rod). I'll try to get some pics next time I'm there for a better idea of what's going on. Pretty sure the building is wood-framed, steel mast though, which is bolted to can't-tell-what through roofing material, with the guy wires attached to "whatever was convenient".

So basically the only 'ground' the coax shield has is where it attaches to the transmitter which presumably has a grounded chassis.

SoundMonkey fucked around with this message at 22:53 on Oct 10, 2013

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

The thing is that our feedline doesn't really HAVE an 'entry point' - it's just run straight from the transmitter, taped to the wall, out an open window and up through the middle of the mast directly to the antenna.


So how is your lovely installation somehow relevant to the examples of a proper installation he showed you. It should have been a big hint that you need to do a better job to make this work, not deride his advice because you are dealing with a sub par hack job.

SoundMonkey posted:

There's no proper grounding to speak of (we don't even have access to the electrical panel to make sure the transmitter is on the same ground as the mixer, much less actually have some fancy poo poo like a grounding rod).

1.) You don't ground the coax to the building electrical ground (you obviously didn't read the materials provided)
2.) A grounding rod is not "fancy". They cost about $12. (you obviously didn't read the materials provided)

If you are asking for advice the absolute least you can do (if you aren't willing to take the advice given) is to not poo poo on the person giving you very good, correct and thorough advice.

poo poo man, you have a mod star. You should know this.

(USER WAS PUT ON PROBATION FOR THIS POST)

Pham Nuwen
Oct 30, 2010



Motronic posted:

2.) A grounding rod is not "fancy". They cost about $12. (you obviously didn't read the materials provided)

I was wondering about this the other day, can you get away with just a chunk of rebar pounded into the dirt? It springs instantly to mind because I spent a good chunk of my childhood putting rebar in the ground for electric fences...

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

Pham Nuwen posted:

I was wondering about this the other day, can you get away with just a chunk of rebar pounded into the dirt? It springs instantly to mind because I spent a good chunk of my childhood putting rebar in the ground for electric fences...

Don't do that. Seriously...there is no reason to do that. A proper ground rod is nothing more than a piece of smooth rebar that's been plated in copper and it's cheap. Get one of those and borrow/rent a hammer drill. 8 or 10 feet (whatever you buy) will disappear into the ground in 10 seconds and within a couple of days will make for a proper grounding system.

When it's that cheap there is literally no excuse to do it wrong.

A proper clamp to attach your grounding wire to it should be less than $2.

And yes, I talking about for electric fences too. Sometimes old farmer cheapness/wisdom isn't so good because they don't keep up with modern materials (ground rods used to be all copper and expensive.....not so much these days and for the last several decades).

Motronic fucked around with this message at 02:29 on Oct 11, 2013

Pham Nuwen
Oct 30, 2010



Motronic posted:

Don't do that. Seriously...there is no reason to do that. A proper ground rod is nothing more than a piece of smooth rebar that's been plated in copper and it's cheap. Get one of those and borrow/rent a hammer drill. 8 or 10 feet (whatever you buy) will disappear into the ground in 10 seconds and within a couple of days will make for a proper grounding system.

When it's that cheap there is literally no excuse to do it wrong.

A proper clamp to attach your grounding wire to it should be less than $2.

And yes, I talking about for electric fences too. Sometimes old farmer cheapness/wisdom isn't so good because they don't keep up with modern materials (ground rods used to be all copper and expensive.....not so much these days and for the last several decades).

Ok, I'll grab a proper grounding rod when I get an HF antenna.

As for electric fences... they always worked fine. We used rebar as fence posts because it was cheap and fast to drive in, and the insulators mounted on it just fine. The sheep didn't stay in one place for long so being able to move the fence easily, without losing a bunch of money every time you bent a post, was important.

Edit: IIRC we had a solid copper rod for grounding the electric system, though.

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

Pham Nuwen posted:

As for electric fences... they always worked fine. We used rebar as fence posts because it was cheap and fast to drive in, and the insulators mounted on it just fine. The sheep didn't stay in one place for long so being able to move the fence easily, without losing a bunch of money every time you bent a post, was important.

Edit: IIRC we had a solid copper rod for grounding the electric system, though.

The edit is the important part.......because what you're saying is that you used rebar as a non-electrical support component because it was cheaper than (or they didn't know about) fiberglass fence rods which have been used for the same purpose for decades and require no insulators.

Pham Nuwen
Oct 30, 2010



Motronic posted:

The edit is the important part.......because what you're saying is that you used rebar as a non-electrical support component because it was cheaper than (or they didn't know about) fiberglass fence rods which have been used for the same purpose for decades and require no insulators.

I'm sorry this is a thing for you, I shouldn't have mentioned it.

Steel posts, $0.99 purchased individually: http://www.orschelnfarmhome.com/fence-post-electric-516/ctl16754/cp58080/si5185377/cl1/

Fiberglass posts, $1.40 each when bought in groups of 20: http://www.orschelnfarmhome.com/38-inch-x-4-foot-fiberglass-post-bundle-of-20/ctl16754/cp58080/si5545920/cl1/

And steel doesn't give you splinters.

SoundMonkey
Apr 22, 2006

I just push buttons.


Motronic posted:

So how is your lovely installation somehow relevant to the examples of a proper installation he showed you. It should have been a big hint that you need to do a better job to make this work, not deride his advice because you are dealing with a sub par hack job.

Except I wasn't deriding his advice, just questioning my ability to follow it?

Calm down, man.

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

Except I wasn't deriding his advice, just questioning my ability to follow it?

Calm down, man.

OK, well....that's not the way I read it. So if that's not how it was intended that's my bad.

So to continue on from here: what exactly can't you follow? This can be as simple as getting a coax lightning arrestor that you attach to the outside of the building, connect the existing line to the feed point of that, connect the arrester ground to a grounding rod, and use a jumper to go from the arrester to the device, preferably by drilling through the wall and properly sealing the hole.

You would also geed a ground line through this hole and ground the chassis of the equipment to the grounding rod.

SoundMonkey
Apr 22, 2006

I just push buttons.


Motronic posted:

OK, well....that's not the way I read it. So if that's not how it was intended that's my bad.

So to continue on from here: what exactly can't you follow? This can be as simple as getting a coax lightning arrestor that you attach to the outside of the building, connect the existing line to the feed point of that, connect the arrester ground to a grounding rod, and use a jumper to go from the arrester to the device, preferably by drilling through the wall and properly sealing the hole.

You would also geed a ground line through this hole and ground the chassis of the equipment to the grounding rod.

I realize the reply may be slightly delayed, but...

Yeah, that was my question - is there something I can do with the existing setup, or will I have to re-work how the feedline is run (which it looks like is the case). If I just pulled the feedline out of the broadcast booth and to the point where it enters the building, then installed a lightning arrestor as you described and ran a jumper to the transmitter, I'd have about fifteen feet of excess coax just sorta lying on the roof. Is this a big enough deal that I should cut and re-crimp the end so it's the right length to go from the antenna to the lightning arrestor, or is it pretty much fine to have a bit of excess cable?

I'll try to find a decent spot on the property for a grounding rod - it's a lot of parking lot and concrete, but I'm sure I can find dirt somewhere.

SoundMonkey fucked around with this message at 22:40 on Oct 11, 2013

Motronic
Nov 6, 2009
Probation
Can't post for 16 hours!

SoundMonkey posted:

I realize the reply may be slightly delayed, but...

Yeah, that was my question - is there something I can do with the existing setup, or will I have to re-work how the feedline is run (which it looks like is the case). If I just pulled the feedline out of the broadcast booth and to the point where it enters the building, then installed a lightning arrestor as you described and ran a jumper to the transmitter, I'd have about fifteen feet of excess coax just sorta lying on the roof. Is this a big enough deal that I should cut and re-crimp the end so it's the right length to go from the antenna to the lightning arrestor, or is it pretty much fine to have a bit of excess cable?

I'll try to find a decent spot on the property for a grounding rod - it's a lot of parking lot and concrete, but I'm sure I can find dirt somewhere.

It's not really going to be a big deal to have another 15 feet of cable. At least it shouldn't be. But if you're handy with terminations, you may as well just lop it off in a convenient location and run it though a hole you've drilled in the wall or through the window frame (be careful to say clear of any mechanicals/weighs/etc in the window if you choose to go through the frame). This way you can make a SMALL hole that will pass only the cable and terminate it after you've run it through.

But yeah, bottom line you really need to rework the entrance. Sure, you could just keep it going through the window after the lightning arrestor, but now seems like a good chance to clean that up.

What frequencies are you running? I can probably suggest a decent arrestor that won't cost $200, but that depends on what frequencies you are trying to pass. And how much power (if it's sub-300 you don't have to get into big bucks).

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MisterOblivious
Mar 17, 2010

by sebmojo

Motronic posted:

What frequencies are you running? I can probably suggest a decent arrestor that won't cost $200, but that depends on what frequencies you are trying to pass. And how much power (if it's sub-300 you don't have to get into big bucks).



SoundMonkey posted:

I volunteer at a local community radio station,

For all these cases, the transmitter was set to 12 watts.

and it's a 30W transmitter).

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